Revista do Instituto de Medicina Tropical de São Paulo
To publish articles dealing with research on tropical diseases and related sciences.
Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo
Genotypic virulence profiles and mobile genetic elements related to invasiveness in Neisseria gonorrhoeae strains
Neisseria gonorrhoeae (NG) has become an increasing global health threat due to drug resistance and potentially invasive disease. In this study, we assessed the genotypic profile in both invasive and non-invasive NG strains from patients at University of Sao Paulo Faculty of Medicine Clinics Hospital, Brazil. We analyzed the NG genotypic profiles and clinical data from 25 patients hospitalized at Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo (HC-FMUSP) from January 2017 to March 2020. A total of 25 isolates underwent whole genome sequencing, of which 10 (40%) were collected from sterile sites like blood and classified as invasive. Invasive and noninvasive specimens were clustered in 5 STs and 11 STs, respectively, sharing 3 STs in common. We identified resistance markers for macrolides (mtrR) in 40% of isolates and 92% exhibited at least one resistance marker for beta-lactams (penA, blaTEM-1B, or blaTEM-135), predominantly PBP1 and PBP2 alterations. Resistance genes blaTEM-1B (7%vs.50%, p=0.023) and tetM (13%vs.80%, p=0.002) were more frequently found in invasive disease isolates, always accompanied by the mobile genetic elements pJD4 and pEP5289, respectively. Associated with these elements were two toxin encoding genes (vapD and zeta1/2) previously described as possible virulence factors and resistance genes for beta-lactams and tetracyclines. Results revealed that invasive strains of NG are genotypically clustered and frequently harbor two plasmids which may be associated with invasive disease. Resistance markers for beta-lactam as PBP1 and PBP2 alterations warn against a future potential resistance to this class.
Copyright (c) 2026 José Victor Bortolotto Bampi, Saidy Vásconez Noguera, Sania Alves dos Santos, Ana Paula Marchi, Marina Farrel Côrtes, Joyce Vanessa da Silva Fonseca, Ivan Lira dos Santos, Flávia Rossi, Maria Luiza Bazzo, Gwenda Hughes, Igor Borges, Silvia Figueiredo Costa https://creativecommons.org/licenses/by-nc/4.0
The COVID-19 pandemic in the hotel industry: the application of hygiene and safety protocols by hotel employees
This study sought to understand how the application of hygiene and safety protocols by hotel companies in Sao Paulo city, Brazil, occurred during the COVID-19 pandemic. The first objective of the study was to find, based on the information provided by employees who worked in certain hotels via questionnaires from March 2020 to December 2022, which protocols were applied in the studied period and which measures were definitively incorporated into the hygiene schemes of these hotels. Secondly, this study aimed to assess how the interaction and adaptations to the implemented hygiene protocols took place to find the measures that have become hygiene habits in everyday life. The literature on the applied health protocols during the pandemic was reviewed. A cross-sectional descriptive study was conducted with 421 respondents. This study found a significant association between sex and the adoption of protective measures during the pandemic. Women adhered more to protective measures than men, and this association remained after the pandemic. Employees who worked in the food and beverage area contracted COVID-19 more often than employees in other hotel areas. Those with higher education levels received more doses of COVID-19 vaccines than those with lower levels of education. Finally, this study found a direct relationship between the quality standard of the hotels and the frequency of training received by employees and a high adherence to vaccination against COVID-19 that was lower at higher educational levels.
Cláudia Regina Rodrigues Sarralheiro Butuhy
Copyright (c) 2026 Cláudia Regina Rodrigues Sarralheiro Butuhy, Expedito José de Albuquerque Luna https://creativecommons.org/licenses/by-nc/4.0
Plasmidial virulence of Rhodococcus equi and its implications of livestock infections for human health: a possible foodborne pathogen?
Rhodococcus equi, a versatile and adapted opportunistic in nature bacterium, infects animals and humans. This soil-borne microorganism widely occurs in farms. Its dissemination occurs by feces from domestic animals (particularly horses, cattle, and pigs). In the last decades, bacterial virulence has been strongly attributed to plasmid-encoded virulence-associated proteins (VAPs). To date, three virulence plasmid types have been recognized: pVAPA, pVAPB, and pVAPN, which are considered host- or livestock-adapted. The pVAPA type is related to equine isolates (horse-type), the pVAPB type is associated with pig isolates (porcine-type), whereas the pVAPN type occurs in domestic ruminants (bovine and caprine) (ruminant-type). Nonetheless, pathogenic R. equi possessing the three virulent plasmid types can infect humans. Inhaling aerosol particles from the environment of equids represents the first route traditionally considered for the transmission of R. equi to humans, although an epidemiological lack of transmission remains in human infections because some patients with rhodococcosis have no history of contact with livestock or their environment on farms. However, all pVAPs types have been found in humans infected by R. equi (predominantly living with HIV), which could be presumably transmitted to patients by the ingestion of contaminated undercooked or raw meat from slaughtered pigs, cattle and, occasionally, horses, representing a probably route of the transmission of the pathogen from livestock-to-humans that could partially explain infections in humans without a history of contact with cattle, pigs, horses, or their farm environments.
Copyright (c) 2026 Márcio Garcia Ribeiro, Alexandre Naime Barbosa, Juliano Gonçalves Pereira, Fábio Sossai Possebon, José Paes de Almeida Nogueira Pinto, Fábio Vinícius Ramos Portilho, Thaís Spessotto Bello, Patrik Júnior de Lima Paz, Marcelo Fagali Arabe Filho, Letícia Colin Panegossi, Alec Utida Reznik, Larissa Onuki Zeferino, Maria Clara Trindade, Nícolas Garcia Ribeiro, Shinji Takai https://creativecommons.org/licenses/by-nc/4.0
A fatal case report of sepsis caused by Robinsoniella sp.
Robinsoniella species are anaerobic, spore-forming, Gram-positive bacilli that are rarely associated with human infections because of their slow growth and the limitations of conventional identification methods. We describe a fatal case of sepsis in an 84-year-old woman with hypertension, diabetes, and chronic renal insufficiency. During hospitalization, she developed impaired consciousness, polymicrobial infections, and multiple organ failure. Despite aggressive antimicrobial and supportive treatment, her condition deteriorated, leading to death. This study identified a Robinsoniella isolate (designated Rp5645) by 16S rRNA gene sequencing, showing 98.35% similarity to R. peoriensis PPC31. As this value falls below the accepted species-level threshold, Rp5645 may represent a novel Robinsoniella species. Unfortunately, the isolate lost viability before further genomic or phenotypic studies could be performed. This outcome illustrates the technical challenges in recovering and preserving fastidious anaerobes and underscores the crucial role of rapid molecular identification in confirming rare pathogens. This case broadens the clinical spectrum of Robinsoniella infections and highlights its potential pathogenic capacity, particularly in older or immunocompromised patients. It also emphasizes the need for timely molecular characterization to prevent the loss of valuable data from uncommon clinical isolates.
Copyright (c) 2026 Meijia Huang, Hongjuan Zhang, Xinyue Li, Xiangchentao Zhang, Yunmin Xu https://creativecommons.org/licenses/by-nc/4.0
Dengue haemorrhagic fever: an evaluation of host innates immune factors in hepatic lesions and their correlation with immunopathogenesis
Dengue fever challenges public health worldwide. The numerous factors associated with dengue fever severity and mortality risk include host characteristics such as patient age, comorbid conditions, previous dengue virus (DENV) infections, and biochemical biomarkers. Type I IFNs are essential cytokines in orchestrating innate and adaptive immune responses against viral invasion, and their regulation is mediated by IRF-2, which prevents excessive IFN expression. In vitro studies have shown DENV evasion strategies that affect IFN-I production but few have considered the in-situ interrelationship between IFN-I and the virus. This study aims to find elements of innate immunity that induce the anti-viral response and their correlation with the detected alterations in liver lesions. Liver specimens from individuals who died due to dengue were selected according to clinical and laboratory data and serological diagnosis. The specimens were subjected to histological and immunohistochemical evaluation of cells expressing IFN-I, RIG-1, IRF-2, and STING. Viral antigens were detected by an anti-DENV. A high number of cells expressed RIG-1 and IRF-2 when compared to IFN-I and STING. In severe cases of dengue, DENV may play a role in its pathogenesis with properties that induce non-effective immune responses. The virus can evade effective immune responses by impairing the early activation of innate immunity. This immune dysregulation may contribute to the progression of more severe manifestations and seems to play a role in the pathogenesis of hepatic involvement.
Copyright (c) 2026 Carla Pagliari, Geovanna Menezes Marcoli, Luciane Kanashiro-Galo, Evandro Sobroza de Mello, Leda Viegas de Carvalho, Ricardo Penny, Juarez Simões Quaresma, Pedro Fernando da Costa Vasconcelos, Mirian Nacagami Sotto https://creativecommons.org/licenses/by-nc/4.0
Rezafungin in fluconazole-resistant and refractory candidiasis: the first Brazilian experience
Invasive candidiasis is associated with high morbidity and mortality, and the rising of antifungal resistance underscores the need for new therapies. Rezafungin, a second-generation echinocandin, enables once-weekly dosing, achieves high plasma concentrations, and shows potent in vitro activity. We report two Brazilian cases showing its clinical utility: (i) fluconazole-resistant Candida tropicalis bloodstream infection in a patient with colorectal cancer and chronic kidney disease and (ii) azole-refractory C. albicans esophagitis in a patient with autoimmune polyglandular syndrome type 1. Both achieved rapid clinical response and microbiological clearance. These are the first documented cases of rezafungin use for invasive candidiasis in Brazil.
Copyright (c) 2026 Wdson Luis Lima Kruschewsky, Jeanne Aiko de Souza Nakagawa, Lumena Pereira Machado Siqueira, Mariane Taborda, Vítor Falcão de Oliveira, Edson Abdala, Adriana Satie Gonçalves Kono Magri, Marcello Mihailenko Chaves Magri https://creativecommons.org/licenses/by-nc/4.0
Streptococcus suis infection as an emerging zoonotic threat in Brazil: a One Health-based review
Streptococcus suis infection is an emerging zoonotic pathogen of growing concern in Brazil, particularly in the Northeast—a region lacking swine-focused surveillance. Although human contamination remains rare, they have been increasingly reported among individuals exposed to pigs or pork products, and most commonly present as central nervous system infections. Diagnostic challenges persist, especially related to culture-based methods, highlighting the need for advanced molecular tools like polymerase chain reaction and metagenomic Next-Generation Sequencing. Veterinary data reveal a high diversity of serotypes and concerning rates of antimicrobial resistance. These studies remain scarce in regions with reports of human infection. This review highlights the clinical, epidemiological, and microbiological aspects of S. suis in Brazil and underscores the importance of One Health approaches to enhance detection and prevention.
Copyright (c) 2026 Luís Arthur Brasil Gadelha Farias, Osvaldo Mariano Viana Neto, Ednaldo Pereira Lima Sobrinho, Antonio Gutierry Neves Dantas de Melo, Isabela Melo Pontes, Bruna Batista Schmid Gonçalves, Helena Pinheiro Benevides, Susana Pereira de Oliveira Maia, Jorge Luiz Nobre Rodrigues, Lauro Vieira Perdigão Neto https://creativecommons.org/licenses/by-nc/4.0
Molecular identification of Bartonella henselae in dogs with clinical suspicion of visceral leishmaniasis
The genus Bartonella includes species responsible for severe infections. Bartonella henselae, commonly linked to human disease, also infects dogs with or without symptoms. In Brazil, visceral leishmaniasis (VL) caused by Leishmania infantum is prevalent in Mato Grosso State, Brazil, particularly in Rondonopolis city, affecting both humans and dogs. Although reports of co-infection with Bartonella spp. and L. infantum exist in other countries, Brazilian studies are scarce. This study investigates the presence of B. henselae using culture and molecular methods in dogs suspected of having VL in Rondonopolis, while also assessing potential co-infections and evaluating diagnostic limitations of VL. Results showed B. henselae DNA in 53.75% (43/80) of these dogs, with Leishmania spp. DNA found in 65.11% (28/43) of them. Of the 80 dogs, 43.75% (35) lacked VL serological confirmation, yet 48.57% (17/35) were positive for B. henselae. This is the first report of B. henselae bacteremia in dogs from Rondonopolis. The high occurrence of dogs with clinical VL suggests a need for further research to understand the bacterium's role in VL-suspected cases, regardless of diagnostic confirmation. The study highlights a significant finding: approximately half of the dogs suspected of zoonotic parasitosis, with or without serological confirmation, were infected with B. henselae. Additionally, the detection of Leishmania sp. DNA in dogs not confirmed by Brazil's Health Department serological criteria suggests that these diagnostic standards may need reevaluation by health authorities, though caution is warranted due to the limitations of blood-based PCR for Leishmania sp. detection.
Copyright (c) 2026 Verônica Domingos Miranda, Luciene Silva dos Santos, Mariana Medeiros Torres, Osvaldo Campos dos Santos Nonato, Adriano Cappellazzo Coelho, Paulo Eduardo Neves Ferreira Velho, Marina Rovani Drummond https://creativecommons.org/licenses/by-nc/4.0
Eosinophilic meningitis caused by Angiostrongylus cantonensis: case report in a patient with false-positive immunological test result for Neisseria meningitides
Eosinophilic meningitis caused by Angiostrongylus cantonensis is an uncommon disease in Brazil that occurs by ingesting slugs, water or food contaminated with the parasite. Here we report a case of a 64-year-old patient with neck stiffness, headache, fever, and peripheral and cerebrospinal fluid (CSF) eosinophilia, compatible with eosinophilic meningitis. He had a false-positive result for Neisseria meningitides and received unsuccessful treatment with antibiotics. After extensive investigation, DNA and anti-A.cantonensis antibodies were detected and the patient was successfully treated with prednisone and albendazole. Diagnosis of neuroangiostrongyliasis relies on epidemiological data, as well as clinical and laboratory examinations such as detection of antibodies and DNA of the parasite in CSF. Its timely treatment with corticosteroid therapy reduces damage to neural tissues and manages headache.
Copyright (c) 2026 Marcela Nataly Parra Alvarez, Juan Sebastián Sánchez León, Tassiane Moreira da Silva, Renato Dumba Monteiro de Castro, Arlete Hilbig, Leyva Cecilia Vieira de Melo, Carlos Graeff-Teixeira, Alessandro Comarú Pasqualotto https://creativecommons.org/licenses/by-nc/4.0
Non-feline transmission of sporotrichosis: a systematic review of published cases
Sporotrichosis is a subcutaneous mycosis caused by species belonging to the genus Sporothrix. While zoonotic transmission has been primarily associated with cats, reports have pointed to sporotrichosis transmission by various non-feline animals, albeit infrequently compared with the aforementioned. These reports suggest the potential for zoonotic or environmentally mediated transmission routes with clinical and epidemiological relevance that have yet to be extensively explored. This systematic review organizes the current knowledge on sporotrichosis acquired by non-feline zoonotic transmission. A comprehensive literature review was conducted from January 1980 to March 2025, leveraging prominent databases like PubMed, SciELO, Web of Science, and EBSCO to identify cases of sporotrichosis transmitted by non-feline animals. A total of 78 cases of sporotrichosis transmitted by non-feline animals were identified in 26 articles. Most cases (76%) were transmitted by vertebrate animals, primarily dogs, whereas 24% were transmitted by invertebrates, such as mosquitoes. Lymphocutaneous presentation predominated among clinical manifestation in 80.7% of cases. Most frequently isolated species was Sporothrix schenckii, whereas Sporothrix brasiliensis was isolated only in infections caused by vertebrate animals. Most patients were young adult males, mainly related with hunting activities. Itraconazole was the most frequently used treatment. Sporotrichosis transmission route via non-feline animals is significant and frequently underestimated. Further research is needed to improve our understanding of the transmission mechanisms, focusing on distinguishing between direct zoonotic transmission and environmental exposure mediated by animal contact. Such enhanced understanding is crucial for improving diagnostic procedures in hyperendemic regions and strengthening epidemiological surveillance.
Copyright (c) 2026 Pamela Rodríguez-Salgado, Andrés Tirado-Sánchez, Valeria Lyzzete Diaz-Molina, Max Carlos Ramírez-Soto, Flavio Queiroz-Telles, Alexandro Bonifaz https://creativecommons.org/licenses/by-nc/4.0
Fulminant hepatitis secondary to dengue in pediatric patients: a series of four cases
This study reports a case series of four pediatric patients with dengue who developed fulminant hepatitis and acute liver failure requiring transplantation. This study aims to enhance early recognition of dengue-related complications, particularly fulminant hepatitis. The series includes two previously healthy girls, aged one and six years; and two boys, aged 12 and 15 years, with pre-existing hemoglobinopathies. A review was conducted to contextualize these cases with prior reports of dengue-associated fulminant hepatitis in children, focusing on diagnosis and management. All four patients underwent liver transplantation, yet their clinical courses and outcomes were varied. Patient 1, a six-year-old girl, had early warning signs and underwent cadaveric liver transplantation nine days after onset. Patient 2, a one--year-old girl, developed severe disease and received living-donor transplantation 20 days after onset. Both had favorable postoperative outcomes. Patient 3, a 12-year-old boy with SC hemoglobinopathy, underwent transplantation on day seven of illness but died on the fifth postoperative day. Patient 4, a 15-year-old boy with sickle cell anemia, underwent transplantation on day four of symptoms but suffered multiple cardiorespiratory arrests during recovery and died on postoperative day 24. Although rare, dengue can lead to fulminant hepatitis in previously healthy children, with worse outcomes in those with comorbidities. Early recognition of severe manifestations is critical for appropriate management. Larger studies are warranted to identify prognostic factors and optimize decision-making for pediatric patients requiring liver transplantation.
Copyright (c) 2026 Isabelly Victoria Simões Melchiori, Mariana Favero Elias, Jhonny Richard de Sousa, Leonardo Labbate Kalil, João Pedro de Mattos Anacleto, Victor Fernandes Rosa, Ana Cristina Aoun Tannuri https://creativecommons.org/licenses/by-nc/4.0
Comparative performance of Filamentous Fungi 4.0 and Mass Spectrometry Identification 2.0 databases for Aspergillus spp.: identification using a simplified protein extraction method
Aspergillus spp. are major agents of pulmonary aspergillosis, posing diagnostic challenges in clinical laboratories due to morphological similarity among species. This study compared the performance of two spectral databases, Filamentous Fungi v4.0 (Bruker Daltonics) and Mass Spectrometry Identification v2.0 (MSI 2.0), for Aspergillus species identification by MALDI-TOF MS, and evaluated the applicability of the simplified protein extraction method from solid culture medium for routine use in hospital laboratories. Overall, 46 clinical isolates from patients with pulmonary aspergillosis were cultured on Sabouraud Dextrose Agar (SDA) at 37 °C for 48 h. Proteins were extracted directly from colonies and analysed using the Bruker MALDI Biotyper system. Spectra were compared against FF_4.0 and MSI_2.0 databases, and results were correlated with molecular identification by benA, cmd5, and ITS gene sequencing. The extraction method yielded high-quality spectra with peaks between 2–15 kDa. The FF_4.0 database identified 52.17% of isolates at the section level and none at the species level, reflecting limited spectral compatibility and taxonomic coverage. Conversely, MSI_2.0 correctly identified 82.6% of isolates at the species level, 15.23% at the section level, and only 2.17% were not identified. Concordance between MSI_2.0 and sequencing reached 44.7%, without statistical significance (p = 0.627). The simplified solid-medium extraction method combined with MSI 2.0 proved efficient, reproducible, and suitable for clinical routine, offering faster identification of Aspergillus species compared to conventional methods. In contrast, FF_4.0 showed limited applicability for hospital workflows.
Copyright (c) 2026 Gustavo Giacon Damiani, Vivian Caso Coelho, Juliana Possato Fernandes Takahashi, Ingrid Gonçalves Costa Leite, Marcia Regina von Zeska Kress, Marcello Mihailenko Chaves Magri, Valdes Roberto Bollela, Roberto Martínez, Gil Benard, Tiago Alexandre Cocio https://creativecommons.org/licenses/by-nc/4.0
Yellow fever virus resurgence in Sao Paulo State, Brazil, 2024–2025
We report the detection of yellow fever virus in Campinas and Ribeirao Preto city areas (two geographic areas within Sao Paulo State, Brazil) from September 2024 to February 2025. Phylogenetic analysis of six new genomes showed a re-introduction in 2022 from Midwest Brazil followed by persistence in Sao Paulo State. Continued surveillance in neotropical primates is required to prevent cases in humans.
Natália Coelho Couto de Azevedo Fernandes
Copyright (c) 2026 Mariana Sequetin Cunha, Juliana Mariotti Guerra, Márcio Junio Lima Siconelli, Benedito Antonio Lopes da Fonseca, Jessica Caroline de Almeida Dias, Gisele Dias de Freitas, Ester Cerdeira Sabino, Erika Regina Manuli, Geovana Maria Pereira, Ian Nunes Valença, Patrícia Sayuri Silvestre Matsumoto, Nuno Rodrigues Faria, Natália Coelho Couto de Azevedo Fernandes https://creativecommons.org/licenses/by-nc/4.0
Occlusion body-incorporated SARS-CoV-2 S-RBD via cypovirus polyhedrin-derived peptide: a novel insect cell-expressed antigen for high-accuracy COVID-19 diagnosis, and humoral immune response and hybrid immunity evaluation
Accurate serological assays are critical for monitoring antibody responses to SARS-CoV-2 and for assessing vaccine efficacy. In this study, we engineered a recombinant baculovirus to express the SARS-CoV-2 spike receptor-binding domain (RBD) fused to an N-terminal peptide of cypovirus polyhedrin (S-RBD-POLH), thereby enabling its potential encapsulation within occlusion bodies. The construct was expressed in insect cells and employed to establish an in-house enzyme-linked immunosorbent assay (ELISA-S) for COVID-19 diagnosis and evaluation of the humoral immune response to SARS-CoV-2. We compared the performance of ELISA-S with a commercial lateral flow immunoassay (LFIA), a chemiluminescence immunoassay (CLIA), and an in-house ELISA targeting Escherichia coli-produced nucleocapsid (N) protein (ELISA-N). Both in-house ELISAs had excellent diagnostic performance (overall accuracy = 0.90), with ELISA-S achieving 98.9% sensitivity and 100% specificity. Inter-assay concordance was high (kappa coefficient > 0.92), with near-perfect agreement between ELISA-S and LFIA (kappa = 0.99). Longitudinal analysis revealed increasing anti-RBD IgG titers over time, in contrast to declining anti-N IgG levels, consistent with expected post-infection kinetics. Moreover, ELISA-S reliably detected antibodies in individuals with hybrid immunity across different periods of the pandemic. These findings establish a scalable platform for antigen encapsulation and production in insect cells to enhance antibody detection. The ELISA-S system represents a robust and adaptable approach for evaluating humoral immunity following infection, vaccination, or hybrid immunity, and can be used for all variants.
Copyright (c) 2026 Murilo Barros-Silveira, Fabricio da Silva Morgado, Laurine Lacerda Pigosso, Fernanda Cortez Roriz Pontes, Ethiane Rozo dos Santos, Rosana Pereira Morais, Yves Mauro Fernandes Ternes, Célia Maria de Almeida Soares, Bergmann Morais Ribeiro, Fátima Ribeiro-Dias https://creativecommons.org/licenses/by-nc/4.0
Reflections on the study "Central sterile supply department management on hospital-associated infections: a systematic review and meta-analysis" by Shuai et al
Copyright (c) 2026 Eliane Molina Psaltikidis https://creativecommons.org/licenses/by-nc/4.0
Fatal cerebral myiasis secondary to squamous cell carcinoma: case report and scoping review
Cerebral myiasis is an exceptionally rare condition caused by infestation with dipteran larvae, with only 20 cases reported in the literature to date. A 78-year-old man presented with anorexia, vomiting, and fever. Physical examination revealed a 7 × 8 cm ulcerated scalp lesion with a necrotic base, purulent discharge, a foul odor, and numerous larvae. Computed tomography demonstrated an osteolytic frontal bone defect accompanied by pneumocephalus and subcutaneous emphysema. The larvae were manually removed, an iodoform dressing was applied, and intravenous ceftriaxone therapy was initiated. Progressive neurological decline prompted repeat imaging, which revealed frontal and parietal cerebritis with abscess formation. Surgical debridement was performed to remove necrotic tissue. Histopathological analysis showed moderately differentiated squamous cell carcinoma with acute osteomyelitis, and cultures yielded multidrug-resistant Pseudomonas aeruginosa. Despite targeted antibiotic therapy and intensive supportive care, the patient died. This case highlights the significant morbidity and mortality associated with cerebral myiasis, particularly when complicated by underlying malignancy and multidrug-resistant infection. Early recognition, prompt surgical intervention, and pathogen-directed antimicrobial therapy are crucial, while comprehensive multidisciplinary management remains essential to optimize outcomes in this life-threatening condition.
Copyright (c) 2026 Paulo Henrique Alves Togni Filho, Ernani Alves de Oliveira, Roscicler Pereira de Sousa, André Luís Santos Vaz Leite, Lucas Eiji Adachi Oliveira, Guilherme Augusto Paro, Julia de Campos Preto https://creativecommons.org/licenses/by-nc/4.0
Leptospirosis-associated pulmonary hemorrhagic syndrome: immune mechanisms, clinical manifestations, and experimental models
<span style="color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;">Leptospirosis is a neglected zoonotic disease caused by bacteria of the genus <em style="box-sizing: border-box; color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">Leptospira<span style="color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;">, mainly acquired via direct contact with water and soil contaminated by the urine of infected animals. This is most observed in tropical and subtropical regions, and it is strongly associated with urban population growth in areas lacking adequate sanitation conditions. <em style="box-sizing: border-box; color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">Leptospira<span style="color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;"> infection can lead to several clinical manifestations in humans, ranging from a nonspecific febrile illness to severe complications such as jaundice, renal failure, and life-threatening pulmonary disease. One of the most severe forms is leptospirosis-associated pulmonary hemorrhagic syndrome (LPHS), characterized by coughing, chest pain, dyspnea, and massive pulmonary hemorrhage. The mortality rate of LPHS is approximately 50%, with death generally occurring within 72 hours after symptom onset. The etiopathogenesis of LPHS remains poorly understood. Some studies suggest that <em style="box-sizing: border-box; color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">Leptospira<span style="color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;"> spp. may directly damage blood capillaries and alter vascular permeability. Additionally, the host immune response, via the cytokine release, high expression of adhesion molecules, and activation of the Complement System, may further disrupt endothelial integrity, promoting vascular leakage and the systemic dissemination of leptospires. Animal models are essential for a better understanding of <em style="box-sizing: border-box; color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">Leptospira<span style="color: #393939; font-family: 'Noto Sans', sans-serif; font-size: 18px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;"> transmission, colonization, and pathogenesis. This review aims to consolidate current understanding of LPHS, with emphasis on its pathogenesis, immune mechanisms, clinical manifestations, virulence factors, and experimental models.
Copyright (c) 2026 Lara Rodrigues da Silva, Milena Carvalho Carneiro, Ana Carolina Mikejevs Lorga, Luana Barbosa Rodrigues dos Santos, Leonardo Moura Midon, Amaro Nunes Duarte Neto, Thais Akemi Amamura, Lourdes Isaac https://creativecommons.org/licenses/by-nc/4.0
SARS-CoV-2 lineage-specific disease symptoms and disease severity in a city in southeastern Brazil
In 2020, Sao Caetano do Sul city, located in the metropolitan region of Sao Paulo State, Brazil, established a web-based platform to provide primary care to suspected COVID-19 patients, integrating clinical and demographic data and sample metadata. Here we describe lineage-specific spatiotemporal dynamics of infections, clinical symptoms, and disease severity during the first year of the epidemic, which included circulation of the poorly characterised Gamma variant of concern. From April 6, 2020, to April 30, 2021, we gathered clinical, demographic, spatial and epidemiological data from the city's platform. We selected and sequenced 879 PCR+ swab samples (8% of all reported cases), obtaining a spatially and temporally representative set of sequences. Daily lineage-specific prevalence was estimated with a moving-window approach, allowing inference of cumulative cases and symptom probability stratified by lineage using integrated data from the platform. Most infections were caused by B.1.1.28 (41.3%), followed by Gamma (31.7%), Zeta (9.6%), and B1.1.33 (9.0%). Gamma and Zeta correlated with larger prevalence of dyspnoea (respectively, 81.3% and 78.5%) and persistent fever (84.7% and 61.1%) compared with B.1.1.28 and B.1.1.33. Ageusia, anosmia, and coryza were respectively 18.9%, 20.3%, and 17.8% less commonly caused by Gamma, whereas altered mental status was 108.9% more common in Zeta. Case incidence was spatially heterogeneous and larger in poorer and younger districts. Our study reveals that Gamma was associated with more severe presentation of the disease, emphasising its role in the heightened mortality levels in Brazil.
Copyright (c) 2026 Flavia Cristina da Silva Sales, Carlos Augusto Prete Junior, Leandro Abade, Lewis Fletcher Buss, Darlan da Silva Candido, Ingra Morales Claro, Filipe Romero Rebello Moreira, Erika Regina Manuli, Ligia Capuani, Camila Alves da Silva Maia, Thais Coletti, Heuder Gustavo Oliveira Paião, Silvia Figueiredo Costa, Maria Cassia Mendes Correa, Fabio Eudes Leal, Kris Varun Parag, Vítor Heloiz Nascimento, Nuno Rodrigues Faria, Ester Cerdeira Sabino https://creativecommons.org/licenses/by-nc/4.0
HIV-associated neurological infections in a Brazilian tertiary care center: clinical-epidemiological features and predictors of in-hospital mortality
Neurological manifestations remain a significant cause of hospitalization and in-hospital mortality among people living with HIV (PLWH), even in the era of antiretroviral therapy (ART). This study aims to describe the clinical and epidemiological profile of PLWH with neurological opportunistic infections (nOIs) and to identify factors associated with in-hospital mortality. We conducted a retrospective cohort study with PLWH aged >18 years hospitalized due to nOIs between November 2017 and December 2021 at a tertiary hospital in Brazil. Demographic, clinical, and laboratory data were extracted from electronic medical records. Logistic regression was used to evaluate associations between patient characteristics and in-hospital mortality. Among 237 hospitalized PLWH, 89 (37.6%) had nOIs. The median CD4 count at admission was 55 cells/mm³ (IQR 22.5–149), and 91.7% had previously used ART (only 22.7% used it regularly). The most frequent infections were cerebral toxoplasmosis (50.6%), cryptococcal meningitis (10.1%), and progressive multifocal leukoencephalopathy (9%). A total of 19 in-hospital deaths occurred. In the multivariate analysis, undefined neurological infections (aOR: 8.67; 95%CI: 1.23–61.17) and ICU admission (aOR: 58.61; 95% CI: 10.24–335.49) were independently associated with mortality. In conclusion, severe immunosuppression and low ART adherence were common in this cohort. Cerebral toxoplasmosis was the most prevalent neurological infection. ICU admission and undefined neurological syndromes were strong predictors of in-hospital mortality. Early diagnosis, prompt treatment, and strategies to improve ART adherence are essential to reduce fatal outcomes in this population.
Copyright (c) 2026 Laísa Rivas Dapousa Ramos, Daniel Ayabe Ninomiya, Murilo Freua Sequeira, Olavo Henrique Munhoz Leite, Marcello Mihailenko Chaves Magri https://creativecommons.org/licenses/by-nc/4.0
Circulating cell-free mitochondrial DNA as a candidate marker of hyperinflammation and immune activation in pre-adolescents, adolescents and young adults with COVID-19 and comorbidities
Youth encompasses pre-adolescence (10-14 years), adolescence (15-17 years), and young adulthood (18-24 years). Adolescents in general, particularly those with comorbidities, appear more susceptible to severe COVID-19, a vulnerability also observed in newborns and young infants. The mechanisms underlying this increased risk remain unclear, highlighting the need for early disease biomarkers. Circulating cell-free mitochondrial DNA (ccf-mtDNA), a damage-associated molecular pattern (DAMP), has been linked to systemic inflammation and immune activation during viral infections. This study evaluated plasma ccf-mtDNA levels in pre-adolescents, adolescents, and young adults with and without COVID-19, all presenting respiratory symptoms and predominantly harboring comorbidities, some with coinfections by other respiratory viruses. In this prospective study of 88 participants aged 12-21 years, half tested positive and half negative for SARS-CoV-2 by Reverse-Transcribed Polymerase Chain Reaction (RT-PCR). Comorbidities were present in 75% of COVID-19-positive and 54.5% of COVID-19-negative participants. Coinfections were detected in 52.3% and 25% of tested participants, respectively. Plasma ccf-mtDNA was quantified by a quantitative Real Time PCR (qPCR) targeting the mitochondrial NADH dehydrogenase 2 (ND2) gene or MT-ND2. COVID-19-positive participants exhibited significantly higher ccf-mtDNA levels than both symptomatic COVID-19-negative individuals and healthy controls (p<0.001). Although median levels were numerically higher in severe/critical compared with mild/moderate cases (7,769 vs. 4,649 ccf-mtDNA/mL), the difference was not statistically significant, likely due to limited sample size. In conclusion, elevated ccf-mtDNA distinguishes young individuals with COVID-19 and comorbidities from non-COVID-19 symptomatic participants and healthy controls. Although not linked to disease severity in this preliminary study, ccf-mtDNA may serve as an early biomarker of SARS-CoV-2-induced hyperinflammation and immune activation, supporting further targeted clinical investigations.
Copyright (c) 2026 Gabriella Bayler Novo, Emilly Henrique dos Santos, Karen Alessandra Rodrigues, Gabriel Acca Barreira, Mariana Okay Saippa, Maria Carolina Pires Cruz, Maria Fernanda Baduê Pereira, Heloisa Helena de Sousa Marques, Thelma Suely Okay https://creativecommons.org/licenses/by-nc/4.0
Contribution of artificial intelligence to the imaging diagnosis of pediatric pulmonary tuberculosis
Pediatric tuberculosis (TB) remains a diagnostic challenge in Brazil and worldwide. The Brazilian Ministry of Health recommends a clinical scoring system (S-MoH) for children and adolescents with suspected TB. Interpretation of radiographs within this scoring system may require specialist input. AI-based systems, such as CAD4TB (Delft Imaging Systems B.V.), approved by the WHO for adults, are not yet recommended for standalone use in children under 15 years of age. A retrospective study was conducted at a pediatric institute from January 31, 2017, to January 29, 2025, including 179 patients aged 0–14 years with pulmonary TB or other diseases. CAD4TBv7.1 analyzed chest radiographs using two cutoff points established by Youden's index: 53.48 for analyses against the S-MoH score and 53.89 for analyses against microbiological confirmation. Results were compared with both microbiological confirmation and S-MoH score. Among the 179 participants, 61 (34.1%) had TB, 25 of which were microbiologically confirmed. CAD4TBv7.1 showed an area under the ROC curve (AUROC) of 0.71, with a sensitivity of 52% and a specificity of 86.3% compared with microbiological diagnosis. Against S-MoH, AUROC was 0.59, with a sensitivity of 34.43% and a specificity of 86.44%. CAD4TBv7.1 demonstrated low sensitivity and high specificity, particularly regarding its overall discriminative capacity. Thus, CAD4TBv7.1 emerges as a promising complementary screening tool for pediatric TB. Although its standalone use is not yet recommended, it may complement S-MoH in settings lacking radiologists. Investments in AI must be accompanied by consistent pediatric validation and strategies that combine technological innovation with traditional and cost-effective clinical approach.
Copyright (c) 2026 Roberta Feijó Carvalho, Sandra Valéria Coelho da Silva, Michely Alexandrino de Souza Pinheiro, Rafaela Baroni Aurilio, Edwin Tao Ming Klinkenberg, Sara Vegas Viedma, Maria de Fátima Bazhuni Pombo Sant’Anna, Ana Alice Amaral Ibiapina Parente, Claudete Aparecida Araújo Cardoso, Clemax Couto Sant’Anna https://creativecommons.org/licenses/by-nc/4.0
Acute/subacute paracoccidioidomycosis associated with drug-resistant tuberculosis in a person living with HIV/AIDS
Paracoccidioidomycosis (PCM) is a neglected tropical disease classified as acute/subacute and chronic. In people living with HIV/AIDS (PLWHA), coinfection can lead to severe clinical manifestations. We report the case of a 30-year-old immunosuppressed male presenting fever, weight loss, polymorphic skin lesions, diffuse lymphadenopathy, hepatosplenomegaly, and joint effusion. Histopathological analysis revealed fungal structures compatible with Paracoccidioides spp., and serology was positive at a titer of 1:16. Despite initial Amphotericin B and antiretroviral therapy, the patient developed a productive cough and persistent systemic symptoms. Initial sputum tests were negative for Mycobacterium tuberculosis, but subsequent bronchoalveolar lavage detected rifampin-resistant tuberculosis (TB). The remarkable overlap of clinical and radiological features of TB and PCM can significantly delay diagnosis, highlighting the need for high clinical suspicion and prompt investigation with bronchoalveolar lavage (BAL) testing. After one-month outpatient follow-up, the patient showed significant cutaneous improvement, undetectable HIV viral load, and a marked increase in CD4+ T-cell count. This report highlights the importance of recognizing the acute/subacute form of PCM as an AIDS-defining illness in endemic areas, enabling early treatment and improved outcomes.
Copyright (c) 2026 Lívia Novaes Teixeira, Nicolas de Albuquerque Weidebach, Ana Angélica Bulcão Portela Lindoso, Cesar Cilento Ponce, José Angelo Lauletta Lindoso https://creativecommons.org/licenses/by-nc/4.0
Variability of clinical presentation and diagnostic challenges in osteoarticular sporotrichosis: a case series
Osteoarticular sporotrichosis is the most common extracutaneous type of the disease and may occur either concomitantly with cutaneous lesions or as isolated musculoskeletal disease, the latter frequently resulting in delayed diagnosis. We describe five confirmed cases of osteoarticular sporotrichosis diagnosed between 2002 and 2023 at a university hospital in Brazil. Diagnosis was confirmed by fungal culture, with serology and histopathology used as complementary methods. Clinical and epidemiological data, radiologic findings, treatment, and outcomes were analyzed. Patients were 39 to 67 years of age and all had chronic conditions or alcoholism. Joint involvement most frequently affected the knee (four cases), followed by the wrist (three cases), and small joint of the hands (two cases), often with bone and periarticular tissue involvement. Three patients had concomitant cutaneous involvement. Diagnostic delays were frequent, reflecting the nonspecific clinical presentation and the tendency to misattribute symptoms to other musculoskeletal conditions. All patients received antifungal therapy with itraconazole and/or amphotericin B. Relapses were recorded in two patients, and there were irreversible sequelae such as chronic arthritis, joint stiffness, or deformity in all cases. Osteoarticular sporotrichosis should be considered in the differential diagnosis of chronic musculoskeletal conditions, including arthritis, osteomyelitis, synovitis, bursitis, and tenosynovitis, particularly in endemic regions. Early recognition and prolonged antifungal therapy are essential to achieve cure and prevent complications.
Copyright (c) 2026 Renê Donizeti Ribeiro de Oliveira, Roberto Martinez, Gilberto Gambero Gaspar, Paulo Louzada Junior, Rodrigo de Carvalho Santana https://creativecommons.org/licenses/by-nc/4.0
Temporal tendencies and spatial patterns of human sporotrichosis in Rio de Janeiro State, Brazil, 2007 to 2023
Cat-transmitted sporotrichosis is one of the fastest spreading zoonosis in Rio de Janeiro State, Brazil. A retrospective study was conducted with analysis of incidence of human sporotrichosis complemented with spatial methodologies. Data from case reported to the Notifiable Diseases Information System (SINAN) from 2007 to 2023 were studied. Incidence, demographic variables, temporal, and spatial dynamics of this endemic disease were investigated. During 2007–2023, 15,401 cases of sporotrichosis were reported. Most cases (64.4%) occurred with women. The annual incidence from 2007 to 2023 was 5.6 cases per 100,000 inhabitants. The incidence in 2016–2023 was 2.3 times higher than in 2007–2015. No significant differences were found regarding age between the two periods, but there were differences regarding gender: with a higher proportion of women in 2007–2015. The endemic is heterogenous with variations in time and space. Spatial analysis showed statistically significant clusters spread throughout Rio de Janeiro, in the periods of low incidence (2007–2015) and high incidence (2016–2023). In the period of high incidence, clusters were more numerous and had a greater range. In conclusion, the incidence levels and the proportion of affected territories increased over time. This study may contribute to understanding the dynamics of the endemic disease in the Rio de Janeiro State and guide control actions in places where they are most needed.
Mônica de Avelar Figueiredo Mafra Magalhães
Copyright (c) 2026 Rafael Ramalho Cunha-e-Silva, Sandro Javier Bedoya-Pacheco, Alex de Oliveira Vasconcelos, Mônica de Avelar Figueiredo Mafra Magalhães, Cristina Maria Giordano Dias, Dayvison Francis Saraiva Freitas, Sandro Antonio Pereira, Anna Barreto Fernandes Figueiredo, Juliana Gonçalves dos Reis, Paula Maria Pereira de Almeida, Cláudia Lima Campos Alzuguir, Liliane de Fátima Antonio Oliveira, Maria Inês Fernandes Pimentel https://creativecommons.org/licenses/by-nc/4.0
Seroepidemiological survey to investigate Rickettsia rickettsii and Rickettsia parkeri in municipalities of the southeast Brazil
Spotted fever is a tick-borne rickettsiosis caused by several Rickettsia species—including R. rickettsii, R. parkeri, and others—with varying degrees of pathogenicity. Its nonspecific symptoms often lead to misdiagnosis such as dengue. This study investigated anti-R. rickettsii and R. parkeri antibodies in 152 patients with acute febrile illness who tested negative for dengue. Serological analysis using immunofluorescence assay found 29 reactive samples (19%) at a 1:64 dilution. Among them, 20.6% were male and 58.6% female, with an average age of 42.6 years. The average sample collection time totaled 14.6 days. Reactive samples included 13.1% for R. rickettsii and 5.9% for R. parkeri. These results suggest possible rickettsial infections in patients initially suspected of dengue.
Copyright (c) 2026 Mariani Borges Franco, Gustavo Cardoso Fonseca, Ana Carolina Prado Sousa, Cristina Rostkwoska, Ana Cláudia Arantes Marquez Pajuaba, José Roberto Mineo, Matias Pablo Juan Szabó, Stefan Vilges de Oliveira https://creativecommons.org/licenses/by-nc/4.0
Safety of two-dose schedule of COVID-19 adsorbed inactivated vaccine (CoronaVac; Sinovac/Butantan) and heterologous additional doses of mRNA BNT162b2 (Pfizer/BioNTech) in immunocompromised and immunocompetent individuals”,
Immunocompromised individuals were considered high-risk for severe disease due to SARS COV-2 infection. This study aimed to describe the safety of two doses of COVID-19 adsorbed inactivated vaccine (CoronaVac; Sinovac/Butantan), followed by additional doses of mRNA BNT162b2 (Pfizer/BioNTech) in immunocompromised (IC) adults, compared to immunocompetent/healthy (H) individuals. This phase 4, multicenter, open label study included solid organ transplant and hematopoietic stem cell transplant recipients, cancer patients and people with inborn errors of immunity with defects in antibody production, rheumatic, end-stage chronic kidney or liver disease, who were enrolled in the IC group. Participants received two doses of CoronaVac and additional doses of mRNA BNT162b2. Adverse reactions (AR) data were collected within seven days after each vaccination. Serious adverse events and of special interest (AESI) were monitored throughout the study. We included 241 immunocompromised and 100 immunocompetent subjects. Arthralgia, fatigue, myalgia, and nausea were more frequent in the IC group after CoronaVac. Following the first additional dose of mRNA BNT162, pain, induration, and tenderness at injection site, fatigue and myalgia were more frequent in the H group. A heart transplant recipient had a graft rejection temporally associated with the second CoronaVac dose, but there was no literature evidence of causal association. Four cases of AESI were considered related to the vaccine: three erythema multiforme after CoronaVac, all in IC participants, and one paresthesia after mRNA, in a H participant. Our findings were comparable to other studies that evaluated the safety of COVID-19 vaccines in different immunocompromised populations. Both vaccines were safe for immunocompromised participants.
Copyright (c) 2025 Karina Takesaki Miyaji https://creativecommons.org/licenses/by-nc/4.0
Spatiotemporal patterns of acute paracoccidioidomycosis hospitalizations in Brazil, 2014-2023
Paracoccidioidomycosis (PCM) is a neglected fungal disease with a rising incidence in Brazil, including increasing hospitalizations in previously non-endemic regions outside the Amazon. This study analyzed the spatiotemporal patterns of acute PCM hospitalizations and their relationship with deforestation. We carried out a retrospective ecological analysis of all PCM-related hospitalizations that were registered in the Brazilian Hospital Information System from 2014 to 2023. Acute and subacute cases were defined using ICD-10 codes (B40.0, B40.7, B40.8, B40.9, B41.0, B41.7, B41.8, and B41.9), whereas chronic forms were excluded. Rates were calculated with census population data and stabilized by Spatial Empirical Bayes smoothing. Space-time cube analysis was applied to detect clusters, which were then compared with deforestation alerts from the DETER-B satellite monitoring system. This study found 4,232 acute PCM hospitalizations, predominantly in men (80%), with a median age of 49 years. Cases were reported in 1,292 municipalities (23%), of which 78% were outside the Amazon. This study also found four significant hotspot clusters, including a newly emergent area in the Cerrado region along the Tocantins–Goias border near Brasilia. Hotspot municipalities showed the largest deforested areas (1,178 km2) when compared to coldspots (24 km2), suggesting a strong spatial association. The spatiotemporal dynamics of acute PCM indicate expansion into deforested areas of the Cerrado, highlighting the role of environmental disruption in shaping disease risk. Mitigating PCM spread in Brazil urgently requires strengthened surveillance and integrated health–environmental policies.
Copyright (c) 2025 Marina Cristina Gadêlha, Gustavo Cezar Wagner Leandro, Deisiany Gomes Ferreira, Amanda de Carvalho Dutra, Rosane Christine Hahn, Luciano de Andrade, Melyssa Negri https://creativecommons.org/licenses/by-nc/4.0
Impact of HIV co-infection on liver fibrosis regression after HCV treatment
Chronic hepatitis C virus (HCV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma, which may lead to liver transplantation. Co-infection with HIV may accelerate liver disease and impact treatment response. Monitoring liver fibrosis involves non-invasive methods such as transient hepatic elastography (THE), AST to Platelet Ratio Index (APRI), and Fibrosis-4 (FIB-4). This study compared changes in THE, APRI, and FIB-4 among patients with HCV alone and those with HIV-HCV co-infection before and after direct-acting antiviral (DAA) therapy. We conducted a retrospective cohort study using medical records from patients treated at a reference clinic in Sao Paulo, Brazil, between January 2015 and February 2019. Fibrosis assessments (THE, APRI, FIB-4) were performed pre-treatment and six months post-treatment. APRI and FIB-4 were also evaluated at 12 months. Among 148 participants, 105 (70%) had HCV mono-infection and 43 (30%) had HIV-HCV co-infection. Genotype 1 was most prevalent (86%). At six months post-treatment, greater reductions in THE, APRI, and FIB-4 were observed in the HCV mono-infection group. Pre-treatment THE values positively correlated with subsequent reductions. However, multivariable analysis showed no significant differences between groups in THE reductions, and no significant group differences in APRI or FIB-4 at six and 12 months. DAA treatment led to fibrosis regression in most participants. HIV co-infection did not significantly alter fibrosis outcomes following successful HCV treatment.
Copyright (c) 2025 Ferdinando Lima de Menezes, Vivian Iida Avelino-Silva, Paulo Roberto Abrão Ferreira https://creativecommons.org/licenses/by-nc/4.0
Retrospective evaluation of the epidemiological importance of Triatoma infestans and Panstrongylus megistus in the transmission of Trypansoma cruzi in a region of southeastern Brazil
Panstrongylus megistus is the most important autochthonous vector of Trypanosom cruzi, the etiological agent of Chagas disease, in the midwest region of the Minas Gerais State, Brazil. This study investigates the vectorial roles of Triatoma infestans and P. megistus in Chagas disease in this geographical area during the late 1970s. A retrospective analysis of entomological and serological surveys from 1975–1983 was conducted, comparing the presence of T. infestans and P. megistus with the seroprevalence of T. cruzi infection in the human population within the Divinopolis Regional Health Superintendency. Panstrongylus megistus was recorded in all surveyed municipalities (52/52), whereas T. infestans co-occurrence with P. megistus was recorded in only 19.2% (10/52) of them. In the 41 municipalities where only P. megistus was found and relevant data were available, the mean seroprevalence of human T. cruzi infection was 17.8% ranging from 1.0% to 41.9%. In the municipalities where T. infestans occurred, the mean seroprevalence was higher, at 25.8%, ranging from 9.8% to 40.8%. Among the municipalities where only P. megistus was present, 19.5% had a low, 29.3% an intermediate, and 51.2% a high seroprevalence of human T. cruzi infection. In the ten municipalities where both T. infestans and P. megitus were found, 80% showed high seroprevalence, whereas only one municipality each showed low or intermediate levels. The findings highlight the significant role of P. megistus in T. cruzi transmission, even in the absence of T. infestans. The wide distribution of P. megistus increased the risk of transmission. P. megistus was the main household vector in the region in the 1970s. Nowadays, continuous surveillance remains essential for monitoring triatomine infestations and evaluating the current risk of T. cruzi transmission.
Copyright (c) 2025 Nilvanei Aparecido da Silva Neves, Rita de Cássia Moreira de Souza, David Eladio Gorla, Lileia Gonçalves Diotaiuti https://creativecommons.org/licenses/by-nc/4.0
Unusual cutaneous manifestations of disseminated Cryptococcus gattii infection in an immunocompetent host
We report a rare case of disseminated Cryptococcus gattii species complex (CGSC) infection in a 51-year-old immunocompetent man who initially had extensive ulcerated skin nodules, an uncommon cutaneous manifestation of cryptococcosis. Positron emission tomography/computed tomography (PET/CT) revealed hypermetabolic lesions in the skin and lungs, while brain magnetic resonance imaging (MRI) demonstrated multiple cryptococcomas with mass effect. The diagnosis was confirmed by skin and lung biopsies and a positive serum cryptococcal antigen test. Induction therapy with lipid complex amphotericin B, flucytosine, and corticosteroids was initiated. This case highlights the importance of recognizing atypical cutaneous lesions as potential indicators of disseminated CGSC infection in immunocompetent individuals, and underscores the need for early antifungal management.
Stephanie Victoria Camargo Leão Edelmuth
Copyright (c) 2025 Carolina Andrade Lopes, Stephanie Victoria Camargo Leão Edelmuth, Alessandra Luna-Muschi, Mariane Taborda, Vítor Falcão de Oliveira, Adriana Satie Gonçalves Kono Magri, Afonso Rafael da Silva Junior, Ana Catharina de Seixas Santos Nastri, Marcello Mihailenko Chaves Magri https://creativecommons.org/licenses/by-nc/4.0