Mem Inst Oswaldo Cruz
· 2025 · PMID 40136144
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BACKGROUND: Rickettsia is a genus of Gram-negative bacteria that causes various diseases, including epidemic typhus, Rocky Mountain spotted fever, and Mediterranean spotted fever. Ticks transmit these diseases and common...BACKGROUND: Rickettsia is a genus of Gram-negative bacteria that causes various diseases, including epidemic typhus, Rocky Mountain spotted fever, and Mediterranean spotted fever. Ticks transmit these diseases and commonly found in developing regions with poor sanitation. As a result, it is difficult to estimate the number of these diseases cases, making it challenging to create prevention and diagnostic mechanisms. OBJECTIVES: Thus, this study aimed to develop an in silico multi-epitope vaccine against Rickettsia. METHODS: Eight proteins were previously identified as potential vaccine candidates through reverse vaccinology and were screened for epitopes that bind to MHC class I and II molecules. The epitopes were then analysed for antigenicity, allergenicity, and toxicity. The selected epitopes were linked with AAY and GPGPG sequences peptide and a known adjuvant, the B-chain of Escherichia coli heat-labile enterotoxin, to form a chimeric multi-epitope protein. The protein's three-dimensional structure was predicted, and molecular docking analysis was performed against the toll-like receptor 4 (TLR4). Finally, the immune response to the protein was simulated using C-ImmSim tool. FINDINGS: A total of 26 immunogenic epitopes, formed the multi-epitope vaccine RGME-VAC/ATS-1. The vaccine showed excellent immunogenic parameters and was predicted to do not be toxic or allergenic to the host. It also showed good potential stimulation of immune cells, with a propensity to generate memory cells and elicit IFN-γ secretion. MAIN CONCLUSIONS: The in silico validations suggest that our study successfully designed an innovative multi-epitope vaccine against Rickettsia, addressing the challenges posed by the elusive nature of diseases caused by this genus. We provide a promising potential for further experimental exploration and the development of targeted prevention and diagnostic strategies for these diseases.
Fonseca GRE, Grossi de Oliveira AL, Brito RMM
… +10 more, Corral MA, Ward RJ, de Lima PA, Rihs JBDR, Cardozo ME, Sato PK, Fujiwara RT, Santos SVD, Gryschek RCB, Lescano SAZ
Mem Inst Oswaldo Cruz
· 2025 · PMID 40105617
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BACKGROUND: Toxocariasis is a neglected global zoonosis. The immunological diagnosis has setbacks that hinder further knowledge about its pathology, epidemiology, and public control measures, and lack of financial suppor...BACKGROUND: Toxocariasis is a neglected global zoonosis. The immunological diagnosis has setbacks that hinder further knowledge about its pathology, epidemiology, and public control measures, and lack of financial support and attention prevents innovative research. Although studies on synthetic peptides are common for several infectious pathologies, none evaluated chemically synthetic peptides for toxocariasis diagnosis. OBJECTIVE: This study aimed to identify potential synthetic peptides from C-type lectin 1 (Tc-CTL-1) from Toxocara canis. METHODS: In silico analyses were made by five B-cell peptide prediction programs, 3-D modelling, BLASTp homology analysis, and signal-peptide identification. SPOT-synthesis was used for epitope mapping and assessed by dot-blot. Sera from non-infected and T. canis, Strongyloides venezuelensis, Ascaris suum, or Schistosoma mansoni-infected animals were used to assess the peptide's immunogenicity and cross-reactivity. The selection of potential immunogenic epitopes included the most immunogenic peptides with the least cross-reactivity. FINDINGS: Fifty-five peptides were selected by in silico analysis. Dot-blot showed intense recognition by anti-Toxocara IgG and cross-reactivity with A. suum-infected mice. Selection criteria identified four epitopes with diagnostic potential. MAIN CONCLUSIONS: The findings demonstrate that synthetic peptides should be explored for innovation of toxocariasis diagnosis, and suggest the adaptation of dot-blot using the SPOT-synthesis technique as a potential immunodiagnostic platform.
Hurton D, Hleba L, Petrová J
… +3 more, Laho M, Koren J, Liptáková A
Mem Inst Oswaldo Cruz
· 2025 · PMID 40105525
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BACKGROUND: Efflux pumps represents one of the most important mechanisms of antibiotic resistance. They allow bacteria to expel antibiotics from their cells before they reach the target site. OBJECTIVES: The main objecti...BACKGROUND: Efflux pumps represents one of the most important mechanisms of antibiotic resistance. They allow bacteria to expel antibiotics from their cells before they reach the target site. OBJECTIVES: The main objective of this work was to examine how cultivation temperature and its variations affect the activity of efflux pumps in Acinetobacter junii, Bacillus cereus, and Enterobacter cloacae isolated from a skin swab. METHODS: The isolation and purification of bacterial colonies were done through the streak plate method. For the identification of bacterial species, MALDI-TOF was utilised. To detect the activity of efflux pumps, agar-ethidium bromide cartwheel method was implemented. FINDINGS: The accumulation of ethidium bromide (EtBr) in bacterial cells was higher at 43ºC than at 30ºC, so the activity of efflux pumps was reduced at 43ºC in all isolates. A temperature of 7ºC also caused increased cumulation of EtBr in the cells, hence decreasing the activity of efflux pumps in isolated bacteria. Moreover, B. cereus was more sensitive to meropenem at 43ºC than at 36ºC. MAIN CONCLUSIONS: The activity of efflux pumps and antibiotic resistance can be strongly affected by changes in incubation temperature in vitro in tested human opportunistic bacterial pathogens.
Moreira CL, Dos Reis IC, Câmara DCP
… +6 more, Ayllón T, Machado MD, Nascimento-Pereira AC, Dos Santos JPC, Burkett-Cadena N, Honório NA
Mem Inst Oswaldo Cruz
· 2025 · PMID 40105524
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BACKGROUND: The Atlantic Forest harbours a rich mosquito assemblage, including vectors for diverse arbovirus. Mosquito species adapt to urban-forest landscape changes, acting as bridge vectors for pathogens. OBJECTIVES:...BACKGROUND: The Atlantic Forest harbours a rich mosquito assemblage, including vectors for diverse arbovirus. Mosquito species adapt to urban-forest landscape changes, acting as bridge vectors for pathogens. OBJECTIVES: This study evaluated different collection methods for immature and adult mosquitoes combined with improving field personnel qualifications in a transition area between urbanised and sylvatic environments. METHODS: Immature and adult mosquitoes were collected from 33 collection points established in urban and peri-urban, sylvatic and transitional areas using different capture methods. During the course, 107 professionals were qualified. FINDINGS: Vectors (Anophelinae and Culicinae) were dominant in the urban/peri-urban environment (51.49%), followed by the transitional (26.69%) and sylvatic (21.82%) environments. Aedes (Stegomyia) albopictus (Skuse), Ae. (Ochlerotatus) scapularis (Rondani), Ae. (Stg.) aegypti (Linnaeus), Haemagogus (Conopostegus) leucocelaenus (Dyar & Shannon), undetermined Culex, Cx. (Melanoconion) pilosus (Dyar and Knab), Cx. (Carrollia) urichii (Coquillett), and Sabethes (Sabethes) albiprivus Theobald were most abundant, with Ae. albopictus collected from all ecotopes. Ovitrap provided a robust sample of the immature stages (92.8%), whereas other methods contributed 3.59% of total immatures, but greatest species richness (14 species). For adult mosquitoes, Shannon light trap resulted in greatest abundance (86.16%). MAIN CONCLUSIONS: The use of varied sampling techniques led to collection of a high mosquito species richness, which, combined with programs for training local professionals, should be an integral part of health surveillance for monitoring the risk of vector-borne diseases.
Yamamoto LS, Trentini MM, Rodriguez D
… +5 more, Silveira PHS, Januzzi AD, Carvalho ACO, Leite LCC, Kanno AI
Mem Inst Oswaldo Cruz
· 2025 · PMID 40053008
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BACKGROUND: Bacillus Calmette-Guérin (BCG) is one of the most successful vaccines in the world and evidence suggests it can be used as a bacterial vector to deliver heterologous antigens. OBJECTIVES: We evaluated whether...BACKGROUND: Bacillus Calmette-Guérin (BCG) is one of the most successful vaccines in the world and evidence suggests it can be used as a bacterial vector to deliver heterologous antigens. OBJECTIVES: We evaluated whether BCG could be biotinylated and used as a carrier of Schistosoma mansoni antigen tetraspanin-2 (TSP-2) fused with rhizavidin, an avidin analog. METHODS: BCG was grown and biotinylated. The recombinant protein Rzv:TSP-2 was produced and purified from Escherichia coli. The biotinylation and antigen coupling was analysed by flow cytometry, enzyme-linked immunosorbent assay (ELISA) and Western blot. Vaccine immunogenicity was tested in immunised mice by the assessment of lung and splenic T cells. FINDINGS: BCG can be biotinylated, which in turn, can be coupled with Rzv:TSP-2. After a series of optimisations which involved molarity of the biotin, ratio of BCG:reagent and the concentration of Rzv:TSP-2 used, almost 50% of the bacteria were biotinylated and 35% coupled with antigen. Although a clear adjuvant effect of BCG was observed, evaluation of immune response in immunised mice demonstrated an overall low immunogenicity of the BCG-Rzv:TSP-2. MAIN CONCLUSION: These results demonstrated the use of BCG as a carrier of avidin-tagged antigens. Further optimisations are needed in order to strengthen the stability of tagged proteins in order to produce antigen-specific immune responses.
Hernández Y, Marson ME, Fernández ML
… +7 more, Sued O, Frola C, Lloret SP, Cahn P, Prado NG, Mastrantonio Garrido GE, Sosa-Estani S
Mem Inst Oswaldo Cruz
· 2025 · PMID 40052995
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BACKGROUND: Benznidazole (BNZ) is the primary treatment for Chagas disease. While pharmacokinetic studies of BNZ began in the 1970s, its metabolism and excretion are not fully understood. Alternatives like Benznidazol La...BACKGROUND: Benznidazole (BNZ) is the primary treatment for Chagas disease. While pharmacokinetic studies of BNZ began in the 1970s, its metabolism and excretion are not fully understood. Alternatives like Benznidazol Lafepe® and Abarax® have replaced the original Radanil®. OBJECTIVES: To compare the pharmacokinetic profiles of both currently available formulations of BNZ in adults with chronic Trypanosoma cruzi infection. METHODS: The study involved 13 subjects each one receiving 100 mg of both presentations one week apart. Blood samples were collected over 48 hours post-administration to analyse BNZ concentration and calculate pharmacokinetic parameters. FINDINGS: The analysis showed that both presentations had similar maximum plasma concentration and time to reach maximum plasma concentration values. Area under curve (AUC) values were slightly lower in Abarax® than Benznidazol Lafepe®. High intra-individual variability was observed, attributed to erratic absorption patterns with multiple peaks in concentration-time curves. The half-life values for both formulations were 9.1 and 8.0 h, respectively, with a significant intra-individual variability over 30%. MAIN CONCLUSIONS: The mean difference in the AUC was lower than 10%, but exceeded the 90% confidence interval for the higher bioequivalence limit. Despite the high variability that confirms erratic absorption, the pharmacokinetic parameters of both formulations were within expected ranges.
Gardinali NR, Marchevsky RS, Vieira YC
… +6 more, Pelajo-Machado M, Kugelmeier T, Melgaço JG, Castro MP, de Oliveira JM, Pinto MA
Mem Inst Oswaldo Cruz
· 2025 · PMID 40052994
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The 2015-16 Zika virus (ZIKV) epidemic has posed unprecedented concern for maternal-infant health, mainly due to the substantial risk of microcephaly and other neurological birth abnormalities associated with congenital...The 2015-16 Zika virus (ZIKV) epidemic has posed unprecedented concern for maternal-infant health, mainly due to the substantial risk of microcephaly and other neurological birth abnormalities associated with congenital ZIKV syndrome (CZS). As licenced vaccines and effective antivirals are still unavailable, attention has been focused on post-delivery in vitro or translational in vivo studies to understand the impact of maternal ZIKV infection on placentation and neurodevelopmental consequences for the foetus. Here, we review clinical and translational studies highlighting ZIKV-induced maternal-foetal interface dysfunction, adding to our previous observations of experimental ZIKV vertical transmission to pregnant rhesus monkeys and newly published post-epidemic findings about the theme. This comparative review focuses on the mechanisms by which the virus has a cytopathic effect on trophoblasts and macrophages during placentation in humans, nonhuman primates, and rodent transgenic models, crosses the placental barrier, replicates, and establishes a persistent uteroplacental infection. When considering the mechanism of ZIKV-induced birth defects in humans and other susceptible hosts, it becomes apparent how the various stages of the ZIKV cycle in the host (both the parent and offspring) unfold. This understanding presents specific opportunities for pharmacological intervention and the development of preventative vaccines.
Sallum MAM, de Azevedo TS, Conn JE
… +1 more, Lourenço-de-Oliveira R
Mem Inst Oswaldo Cruz
· 2025 · PMID 40008702
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In 1909, Arthur Neiva published an article titled "Contribuição para os estudos dos dipteros. Observação sobre a biolojia e sistematica das anofelinas brasileiras e suas relações com o impaludismo", highlighting the biol...In 1909, Arthur Neiva published an article titled "Contribuição para os estudos dos dipteros. Observação sobre a biolojia e sistematica das anofelinas brasileiras e suas relações com o impaludismo", highlighting the biology, ecology, and distribution of Anophelinae mosquitoes and the need for more taxonomic studies in Brazil. This came 11 years after Ronald Ross and Grassi demonstrated mosquito roles in transmitting Plasmodium to birds and humans. Despite considerable advances in the understanding of Anophelinae species, knowledge remains insufficient given the complexity of Brazil's ecosystems, the intensified anthropogenic environmental changes since the mid-20th century, and the persistent public health challenges posed by malaria. This perspective article presents the distribution of Plasmodium vectors and potential vector species in Brazil using climate variables and a maximum entropy model. Geographical distribution maps of Anophelinae species, including putative species, are provided. The article also discusses the current knowledge of vector species distribution in relation to Brazil's malaria elimination plan, along with the ecological and anthropogenic factors influencing vector distribution.
Mem Inst Oswaldo Cruz
· 2025 · PMID 40008701
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Free-living amoebas (FLA) are ubiquitous protists found in the environment. They have shown exceptional resistance to environmental challenges and play significant roles in controlling microbial populations through their...Free-living amoebas (FLA) are ubiquitous protists found in the environment. They have shown exceptional resistance to environmental challenges and play significant roles in controlling microbial populations through their predatory behaviour and microbicidal activity in both soil and aquatic ecosystems environments. However, although rare, a limited group of FLA can cause serious infections in the central nervous system and other diseases, particularly in immunocompromised individuals with high mortality rates. They can also cause keratitis in otherwise healthy individuals. This review offers a comprehensive overview of freshwater naked amoebae but does not cover all aspects in detail. Its goal is to provide a historical context for our current understanding while addressing the most critical elements of FLA biology, their pathogenic potential, and their interactions with important human pathogens.
Mem Inst Oswaldo Cruz
· 2025 · PMID 40008700
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BACKGROUND: The works of Lutz & Neiva, published 115 years ago in the Memórias do Instituto Oswaldo Cruz, are pioneering for the study of Neotropical Tabanidae. These studies emphasised the importance of biological colle...BACKGROUND: The works of Lutz & Neiva, published 115 years ago in the Memórias do Instituto Oswaldo Cruz, are pioneering for the study of Neotropical Tabanidae. These studies emphasised the importance of biological collections and the description of species from the exploration of South American areas. Dasybasis Macquart, 1847 has traditionally been considered a large genus of tabanids restricted to the Australasian, Neotropical, and Andean regions. Dasybasis species exhibit a high degree of morphological similarity, making specific differentiation challenging. Moreover, some of these features are also present in other taxa, suggesting that they may not be homologous characters and should not be used to define the genus. OBJECTIVES: This study aimed to assess the monophyly of Dasybasis and establish its major monophyletic groups. METHODS: We conducted an implied weighting analysis using morphological characters, and wing landmarks from 91 terminal species. FINDINGS: For the total evidence analyses, aligning with either Tabanus Linnaeus or Dasybasis appendiculata Macquart yielded slightly different trees. Classical morphology and total evidence topology aligned with D. appendiculata are the same, while differing from the total evidence topology aligned with Tabanus in two nodes. MAIN CONCLUSIONS: Our results indicate that Dasybasis was not a monophyletic group, and that this name should be restricted to species with a distribution in Australasia; while Neotropical Dasybasis species are recovered in different clades. The genera Archiplatius, Pseudoselasoma, and Stypommia are revalidated. This study provides a revised phylogenetic framework for "Dasybasis" and related taxa, highlighting the need for a more nuanced understanding of morphological character evolution within the tribe Diachlorini.
Rocha IV, Bezerra MF, Sobreira M
… +1 more, de Almeida AMP
Mem Inst Oswaldo Cruz
· 2025 · PMID 40008699
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The history of the plague, caused by Yersinia pestis, is marked by some of the most devastating pandemics. Its arrival in Brazil on the turn of the 19-20th century led to significant public health challenges and response...The history of the plague, caused by Yersinia pestis, is marked by some of the most devastating pandemics. Its arrival in Brazil on the turn of the 19-20th century led to significant public health challenges and responses. Here, we discuss a comprehensive perspective on the history of the plague in Brazil, emphasising epidemiological trends, public health responses and scientific advances. Understanding the history of the plague in Brazil provides valuable insights into infectious disease control. The study highlights the importance of early detection, robust public health infrastructure, and ongoing research, emphasising the lasting influence of epidemic diseases on society.
Mem Inst Oswaldo Cruz
· 2025 · PMID 40008698
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Haemosporida research started in the 19th century with the description of Plasmodium and other related parasites infecting mammals and birds. Here, we highlight the pioneering contributions of Henrique Aragão and Arthur...Haemosporida research started in the 19th century with the description of Plasmodium and other related parasites infecting mammals and birds. Here, we highlight the pioneering contributions of Henrique Aragão and Arthur Neiva in describing the first two Plasmodium species in lizards from the New World, Plasmodium diploglossi and Plasmodium tropiduri, published in the first printed issue of Memórias do Instituto Oswaldo Cruz in April 1909. We use these discoveries as a background to explore some historical and taxonomic aspects of Plasmodium species infecting reptiles, with a particular emphasis on the advancements made over the past 115 years in the Neotropics. Our review underscores the complexities and persistent challenges in the taxonomic classification of reptile haemosporidians and discusses some scientific advances in the field that improved our understanding of the biology and evolution of these parasites.
Veira C, Benítez D, Pérez-Díaz L
… +3 more, Álvarez G, Cerecetto H, Aguilera E
Mem Inst Oswaldo Cruz
· 2025 · PMID 39936704
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BACKGROUND: The neglected illness Chagas disease is treated with limited efficacy and adverse effects by old drugs. Due to the low interest of pharmaceutical industry in targeting economically depressed-patients, repurpo...BACKGROUND: The neglected illness Chagas disease is treated with limited efficacy and adverse effects by old drugs. Due to the low interest of pharmaceutical industry in targeting economically depressed-patients, repurposing is a tool that should be applied because it can introduce new anti-Chagas entities into the clinic at reduced costs. OBJECTIVES: To investigate the repurposing/combination of medicines strategies as anti-Chagas treatment. METHODS: Epimastigotes, trypomastigotes and amastigotes of Trypanosoma cruzi were in vitro exposed to 28 Uruguayan-approved medicines not previously tested, 28 FDA-approved medicines previously evaluated, and three reference agents. Parasite inhibition was assessed and for the best drugs, in pairs-isobolographic studies, looking for synergism/additivity/antagonism, were done. Macrophages were used to study selectivity. For some relevant agents, we analysed whether medicines mammals´ action mechanisms are operative in epimastigotes-T. cruzi. FINDINGS: From the anti-epimastigotes monotherapy-screening, we found that 18% of them showed better/comparable activities than references. Additionally, for the binary-combinations 8% were additive, 4% were synergic and the rest showed antagonism. Favourably, in macrophages-cytotoxicity four of the binary-combinations were antagonists. Naftazone and pinaverium bromide, not previously tested against T. cruzi, maintained their activity against trypomastigotes and amastigotes. The identified action mechanisms open the door to new strategies designing anti-T. cruzi drugs. MAIN CONCLUSIONS: Using approved-medicines is a good strategy for new anti-Chagas treatments.
Sheu-Idrees R, Marques GVL, Santana PAL
… +8 more, Diniz LA, Resende DM, Odoma S, Olorunshola O, Ferreira RS, Murta SMF, Maltarollo VG, de Oliveira RB
Mem Inst Oswaldo Cruz
· 2025 · PMID 39936703
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BACKGROUND: Chagas disease (CD) is a neglected tropical disease caused by Trypanosoma cruzi. The current drugs used to treat these diseases have limited efficacy and produce severe side effects. 4-aminoquinoline derivati...BACKGROUND: Chagas disease (CD) is a neglected tropical disease caused by Trypanosoma cruzi. The current drugs used to treat these diseases have limited efficacy and produce severe side effects. 4-aminoquinoline derivatives were shown to be a promising class of inhibitors of cysteine proteases cruzain and TbrCATL. OBJECTIVES: To evaluate the trypanocidal activity of a new series of aminoquinolines as potential inhibitors of cruzain and TbrCATL. METHODS: Three aminoquinolines were synthesised and their in vitro activity was evaluated against cruzain and TbrCATL as well as against amastigotes and trypomastigotes forms of T. cruzi. In silico studies were also carried out to try to understand the experimental results. FINDINGS: Compound 5 showed promising activity against cruzain and TbrCATL, with better performance than E60, the reference drug. Compound 5 inhibited cruzain and TbrCATL at IC50 of 23 µM ±3 and 29 µM ±1, respectively, but this inhibition showed characteristics of promiscuous inhibition by colloidal aggregation. On the other hand, the compound 4 showed to be more promising activity against T. cruzi with IC50 2.57 µM ± 0.03 lower than the reference drug benznidazole 3.8 µM. MAIN CONCLUSIONS: The results of this study can guide new drug development for the treatment of trypanosomiasis.
Siqueira-E-Silva BN, de Sousa LP, Rosa-Gonçalves P
… +4 more, da Silva RM, Martins YC, Brasil P, Daniel-Ribeiro CT
Mem Inst Oswaldo Cruz
· 2025 · PMID 39907418
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Malaria, caused by Plasmodium spp., remains a major public health problem. Cerebral malaria is its deadliest form, with a 15-25% mortality rate, despite artemisinin-based treatments. In addition, the World Health Organiz...Malaria, caused by Plasmodium spp., remains a major public health problem. Cerebral malaria is its deadliest form, with a 15-25% mortality rate, despite artemisinin-based treatments. In addition, the World Health Organization (WHO) strictly defines cerebral malaria as the presence of coma, 1 h after a seizure or the correction of hypoglycemia, in patients with P. falciparum parasitemia. Consequently, 25% of survivors experience neurocognitive and behavioral sequelae, particularly in children. However, more recently, neurocognitive and behavioral impairments were also reported in severe non-cerebral malaria, non-severe malaria, and even during asymptomatic Plasmodium infection. Such impairments have been observed in school-aged children, the elderly, and in animal models without classic cerebral malaria pathology. Additionally, mild vasogenic edema has been detected in neuroimaging of patients with severe non-cerebral and non-severe P. falciparum malaria. Therefore, given that approximately 98% of malaria cases in the world are non-severe, neurocognitive and behavioral sequelae may account for a significant proportion of global malaria morbidity. Taken together, these observations suggest that systemic inflammation from malaria, even without traditional cerebral malaria signs, can disrupt brain function and lead to long-term sequelae. We propose that the current definition of cerebral malaria may not fully capture the observed evidence and a new conceptualization is necessary to encompass these findings.
Mem Inst Oswaldo Cruz
· 2025 · PMID 39907417
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BACKGROUND: Non-O1 and non-O139 Vibrio cholerae (NOVC) that cause bacteraemia have attracted the attention of the public health community around the world, mainly due to the prospect of outbreaks and the way to treat suc...BACKGROUND: Non-O1 and non-O139 Vibrio cholerae (NOVC) that cause bacteraemia have attracted the attention of the public health community around the world, mainly due to the prospect of outbreaks and the way to treat such infections. OBJECTIVES: To identify V. cholerae lineages and their antibiotic resistance and virulence factors associated with bacteraemia. METHODS: Vibrio cholerae genomes associated with strains isolated from blood were retrieved and subjected to core genome-based phylogenomic analysis with Roary. The virulome and resistome were searched with abricate using the VFDB and CARD databases. FINDINGS: Analysis showed that, in addition to V. cholerae, Vibrio paracholerae also causes bacteraemia. The NOVC group was highly diverse, although genomes from different countries were related. Most bacteraemic Vibrios came from countries not affected by epidemic/endemic cholera. The NOVCs virulome presented factors, such as type III and VI secretion systems, HapA, HlyA, RTX, and TLH. Importantly, no resistance to third-generation cephalosporin has been identified in the resistome of NOVCs. MAIN CONCLUSIONS: The presence of multiple NOVC lineages that cause bacteraemia in different parts of the world shows that there is no geographic and socioeconomic restriction for these cases. Therefore, healthcare systems need to be aware of this uncommon but deadly Vibrio infection.
Mem Inst Oswaldo Cruz
· 2025 · PMID 39907416
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BACKGROUND: The nematode Angiostrongylus cantonensis, which is endemic to Southeast Asia and adjacent Pacific Islands, has already been recorded in more than 30 countries, including Brazil and other South American nation...BACKGROUND: The nematode Angiostrongylus cantonensis, which is endemic to Southeast Asia and adjacent Pacific Islands, has already been recorded in more than 30 countries, including Brazil and other South American nations. It is one of the principal etiological agents of the zoonosis Eosinophilic Meningitis (EoM), which has a number of different species of terrestrial gastropods that act as its intermediate hosts. OBJECTIVE: The present study investigated the occurrence of the larvae of this nematode in specimens of terrestrial molluscs collected in half of the municipalities of the Brazilian State of Rio de Janeiro. METHODS: The study is based on the surveillance of this nematode in the Brazilian State of Rio de Janeiro, where terrestrial snails and slugs were collected in more than half of the state's municipalities (46 in all), and examined for parasitological infections. The nematode larvae retrieved from these specimens were identified based on their morphology and cytochrome oxidase I (COI) mitochondrial DNA sequences. FINDINGS: Angiostrongylid larvae were found in 230 (8.8%) of the 2,600 terrestrial molluscs examined, collected from 26 municipalities. Overall, 14 terrestrial gastropod species were identified, including both native and exotic taxa, and six were found to be infected naturally by A. cantonensis. The natural infection rates by Angiostrongylus in the different terrestrial molluscs species were 12.5% in Angustipes erinaceus, 9.7% in Achatina fulica, 6.8% in Bradybaena similaris, 6.3% in Sarasinula linguaeformis, 3.9% in Leptinaria unilamellata, and 4.6% in Subulina octona. A. fulica was the most frequent and extensively distributed species, with infected snails being found in 22 municipalities. MAIN CONCLUSIONS: The data from this first comprehensive survey of A. cantonensis in Rio de Janeiro highlights the potential epidemiological risk of human infection in this state. Mapping the spread of infected molluscs will also provide essential information for the evaluation of the risk of human infection, and should help local health authorities to provide a faster and more accurate diagnosis whenever neuroangiostrongyliasis is suspected.
Mem Inst Oswaldo Cruz
· 2025 · PMID 39841756
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Diphtheria, a severe respiratory infection, was a major killer of children until the early years of the 20th century. Although diphtheria is now largely controlled globally thanks to vaccination, it is still endemic in s...Diphtheria, a severe respiratory infection, was a major killer of children until the early years of the 20th century. Although diphtheria is now largely controlled globally thanks to vaccination, it is still endemic in some world regions and large epidemics can occur where vaccination coverage is insufficient. The pathological effects caused by its main virulence factor, diphtheria toxin, can be diminished by passive transfer of antibodies. Equine diphtheria antitoxin (eDAT), the cornerstone of treatment against toxinic complications of diphtheria, was invented more than 130 years ago, in 1890, and is still in use today. A method to concentrate anti-diphtheria antibodies from hyperimmune equine serum was described in the first issue of Memórias do Instituto Oswaldo Cruz in 1909. On this historic occasion, we present recent knowledge on taxonomic, epidemiological and clinical aspects of diphtheria agents that produce diphtheria toxin, and provide a historical perspective on eDAT treatment, adverse effects, threats on its scarce international supply, and current avenues for alternative therapeutic strategies.
Souza PJ, Fernandes J, Coelho TA
… +9 more, Cosentino M, D'arc M, Alves PDG, Guterres A, Vilar EM, Lemos ERS, Cordeiro-Estrela P, Santos AFA, Oliveira RC
Mem Inst Oswaldo Cruz
· 2024 · PMID 39699489
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BACKGROUND: Bat-borne hantaviruses have been identified worldwide but little is known about neotropical bats in the megadiverse biomes of the American continent. Although serological evidence has hinted at hantavirus cir...BACKGROUND: Bat-borne hantaviruses have been identified worldwide but little is known about neotropical bats in the megadiverse biomes of the American continent. Although serological evidence has hinted at hantavirus circulation in Brazil, the scarce number of genomic detection represents a gap to understand viral diversity, prevalence, and ecology of bat-borne hantaviruses. OBJECTIVE: We aim to investigate and evaluate the presence and prevalence of bat-borne hantavirus in the Brazilian Atlantic Forest. METHODS: Here in, 97 lung and kidney tissue samples from bats captured in the Brazilian Atlantic Rainforest were submitted to hantavirus-specific nested reverse transcription-polymerase chain reaction (RT-PCR) targeted the hantaviral L segment and metagenomic analysis. FINDINGS: Hantavirus RNA was detected in five tissue fragments of 20 Seba's short-tailed bats (Carollia perspicillata). Phylogenetic analysis, based on partial L-segment sequence using maximum likelihood method, demonstrated that the identified virus formed a monophyletic clade and a highly divergent bat-borne lineage comprising other recent strains found in the genus Carollia from South America. MAIN CONCLUSIONS: Our findings suggest the presence of a novel bat-borne hantavirus in Brazil, tentatively named Mamanguape virus (MGPV). Additional genomic data will help to extend our knowledge about the classification of MGPV within the Hantaviridae family and the evolution origins of new world bat-borne hantaviruses.