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1.
Viruses ; 15(11)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38005922

RESUMO

Zika virus (ZIKV) and yellow fever virus (YFV) originated in Africa and expanded to the Americas, where both are co-circulated. It is hypothesized that in areas of high circulation and vaccination coverage against YFV, children of pregnant women have a lower risk of microcephaly. We evaluated the presence and titers of antibodies and outcomes in women who had ZIKV infection during pregnancy. Pregnancy outcomes were classified as severe, moderate, and without any important outcome. An outcome was defined as severe if miscarriage, stillbirth, or microcephaly occurred, and moderate if low birth weight and/or preterm delivery occurred. If none of these events were identified, the pregnancy was defined as having no adverse effects. A sample of 172 pregnant women with an acute ZIKV infection confirmed during pregnancy were collected throughout 2016. About 89% (150 of 169) of them presented immunity against YFV, including 100% (09 of 09) of those who had severe outcomes, 84% (16 of 19) of those who had moderate outcomes, and 89% (125 of 141) of those who had non-outcomes. There was no difference between groups regarding the presence of anti-YFV antibodies (p = 0.65) and YFV titers (p = 0.6). We were unable to demonstrate a protective association between the presence or titers of YFV antibodies and protection against serious adverse outcomes from exposure to ZIKV in utero.


Assuntos
Microcefalia , Infecção por Zika virus , Zika virus , Criança , Recém-Nascido , Feminino , Humanos , Gravidez , Vírus da Febre Amarela , Resultado da Gravidez , Anticorpos Antivirais
2.
Viruses ; 15(6)2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37376655

RESUMO

Zika virus (ZIKV) is an RNA flavivirus (Flaviviridae family) endemic in tropical and subtropical regions that is transmitted to humans by Aedes (Stegomyia) species mosquitoes. The two main urban vectors of ZIKV are Aedes aegypti and Aedes albopictus, which can be found throughout Brazil. This study investigated ZIKV infection in mosquito species sampled from urban forest fragments in Manaus (Brazilian Amazon). A total of 905 non-engorged female Ae. aegypti (22 specimens) and Ae. albopictus (883 specimens) were collected using BG-Sentinel traps, entomological hand nets, and Prokopack aspirators during the rainy and dry seasons between 2018 and 2021. All pools were macerated and used to inoculate C6/36 culture cells. Overall, 3/20 (15%) Ae. aegypti and 5/241 (2%) Ae. albopictus pools screened using RT-qPCR were positive for ZIKV. No supernatants from Ae. aegypti were positive for ZIKV (0%), and 15 out of 241 (6.2%) Ae. albopictus pools were positive. In this study, we provide the first-ever evidence of Ae. albopictus naturally infected with ZIKV in the Amazon region.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Humanos , Animais , Feminino , Zika virus/genética , Brasil/epidemiologia , Mosquitos Vetores
3.
Viruses ; 15(3)2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36992479

RESUMO

Zika virus (ZIKV) is transmitted to humans by the infectious bite of mosquitoes such as Aedes aegypti. In a city, the population control of mosquitoes is carried out according to alerts generated by different districts via the analysis of the mosquito index. However, we do not know whether, besides mosquito abundance, the susceptibility of mosquitoes could also diverge among districts and thus impact the dissemination and transmission of arboviruses. After a viremic blood meal, the virus must infect the midgut, disseminate to tissues, and reach the salivary gland to be transmitted to a vertebrate host. This study evaluated the patterns of ZIKV infection in the Ae. aegypti field populations of a city. The disseminated infection rate, viral transmission rate, and transmission efficiency were measured using quantitative PCR at 14 days post-infection. The results showed that all Ae. aegypti populations had individuals susceptible to ZIKV infection and able to transmit the virus. The infection parameters showed that the geographical area of origin of the Ae. aegypti influences its vector competence for ZIKV transmission.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Animais , Humanos , Zika virus/genética , Brasil/epidemiologia , Saliva , Mosquitos Vetores
4.
Malar J ; 21(1): 343, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36397077

RESUMO

BACKGROUND: The groundwork for malaria elimination does not currently consider the potential of Plasmodium zoonotic cycles that involve non-human primates (NHPs) in sylvatic environments. Since vivax malaria is less responsive to control measures, finding Plasmodium vivax infected NHPs adds even more concern. METHODS: Both Free-living monkeys in forest fragments inside the urban area and captive monkeys from a local zoo had blood samples tested for Plasmodium species. RESULTS: In this study, among the Neotropical monkeys tested, three (4.4%), one captive and two free-living, were found to be naturally infected by P. vivax. CONCLUSION: This important finding indicates that it is necessary to estimate the extent to which P. vivax NHP infection contributes to the maintenance of malaria transmission to humans. Therefore, the discussion on wildlife conservation and management must be incorporated into the malaria elimination agenda.


Assuntos
Malária Vivax , Malária , Plasmodium , Animais , Malária Vivax/prevenção & controle , Erradicação de Doenças , Plasmodium vivax , Malária/prevenção & controle
5.
Rev Soc Bras Med Trop ; 55: e0427, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36000618

RESUMO

BACKGROUND: Arthropod-borne viruses have recently emerged and are pathogens of various human diseases, including dengue, zika, and chikungunya viruses. METHODS: We collectedAedes aegyptilarvae (N = 20) from Brumado, Bahia, Brazil, and treated and individually preserved the specimens. We analyzed the samples for dengue, zika, and chikungunya viruses using molecular biology methods. RESULTS: We found that 25% (N = 5) and 15% (N = 3) were positive exclusively for dengue and chikungunya viruses, respectively; 15% (N = 3) were coinfected with both. CONCLUSIONS: This is the first report of dengue and chikungunya virus coinfection in A. aegypti larvae.


Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Vírus da Dengue , Dengue , Infecção por Zika virus , Zika virus , Animais , Brasil , Vírus Chikungunya/genética , Vírus da Dengue/genética , Humanos , Mosquitos Vetores
6.
Parasit Vectors ; 15(1): 57, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177110

RESUMO

BACKGROUND: Emerging and re-emerging vector-borne diseases (VBDs) pose a recurring threat to tropical countries, mainly due to the abundance and distribution of the Aedes aegypti mosquito, which is a vector of the Zika, dengue, chikungunya, and yellow fever arboviruses. METHODS: Female 3-5 day-old Ae. aegypti were distributed into two experimental groups: group I-survey of cultivable bacteria; sucrose group: fed only on sucrose, i.e., non-blood-fed (UF); blood-fed group: (i) fed with non-infected blood (BF); (ii) fed with blood infected with the Zika virus (BZIKV); (iii) pretreated with penicillin/streptomycin (pen/strep), and fed with non-infected blood (TBF); (iv) pretreated with pen/strep and fed blood infected with ZIKV, i.e., gravid with developed ovaries, (TGZIKV); group II-experimental co-infections: bacteria genera isolated from the group fed on sucrose, i.e., non-blood-fed (UF). RESULTS: Using the cultivable method and the same mosquito colony and ZIKV strain described by in a previous work, our results reveled 11 isolates (Acinetobacter, Aeromonas, Cedecea, Cellulosimicrobium, Elizabethkingia, Enterobacter, Lysinibacillus, Pantoea, Pseudomonas, Serratia, and Staphylococcus). Enterobacter was present in all evaluated groups (i.e., UF, BF, BZIKV, TBF, and TGZIKV), whereas Elizabethkingia was present in the UF, BZIKV, and TBF groups. Pseudomonas was present in the BZIKV and TBF groups, whereas Staphylococcus was present in the TBF and TGZIKV groups. The only genera of bacteria that were found to be present in only one group were Aeromonas, Lysinibacillus, and Serratia (UF); Cedacea, Pantoea and Acinetobacter (BF); and Cellulosimicrobium (BZIKV). The mosquitoes co-infected with ZIKV plus the isolates group fed on sucrose (UF) showed interference in the outcome of infection. CONCLUSIONS: We demonstrate that the distinct feeding aspects assessed herein influence the composition of bacterial diversity. In the co-infection, among ZIKV, Ae. aegypti and the bacterial isolates, the ZIKV/Lysinibacillus-Ae. aegypti had the lowest number of viral copies in the head-SG, which means that it negatively affects vector competence. However, when the saliva was analyzed after forced feeding, no virus was detected in the mosquito groups ZIKV/Lysinibacillus-Lu. longipalpis and Ae. aegypti; the combination of ZIKV/Serratia may interfere in salivation. This indicates that the combinations do not produce viable viruses and may have great potential as a method of biological control.


Assuntos
Aedes , Microbiota , Infecção por Zika virus , Zika virus , Animais , Feminino , Mosquitos Vetores
7.
Rev. Soc. Bras. Med. Trop ; 55: e0427, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1394692

RESUMO

ABSTRACT Background: Arthropod-borne viruses have recently emerged and are pathogens of various human diseases, including dengue, zika, and chikungunya viruses. Methods: We collectedAedes aegyptilarvae (N = 20) from Brumado, Bahia, Brazil, and treated and individually preserved the specimens. We analyzed the samples for dengue, zika, and chikungunya viruses using molecular biology methods. Results: We found that 25% (N = 5) and 15% (N = 3) were positive exclusively for dengue and chikungunya viruses, respectively; 15% (N = 3) were coinfected with both. Conclusions: This is the first report of dengue and chikungunya virus coinfection in A. aegypti larvae.

8.
PLoS Negl Trop Dis ; 15(11): e0009839, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34727099

RESUMO

Dengue virus (DENV) and Zika virus (ZIKV) belong to the same viral family, the Flaviviridae. They cause recurring threats to the public health systems of tropical countries such as Brazil. The primary Brazilian vector of both viruses is the mosquito Aedes aegypti. After the mosquito ingests a blood meal from an infected person, the viruses infect and replicate in the midgut, disseminate to secondary tissues and reach the salivary gland (SG), where they are ready to be transmitted to a vertebrate host. It is thought that the intrinsic discrepancies among mosquitoes could affect their ability to deal with viral infections. This study confirms that the DENV and ZIKV infection patterns of nine Ae. aegypti field populations found in geographically separate health districts of an endemic Brazilian city vary. We analyzed the infection rate, disseminated infection, vector competence, and viral load through quantitative PCR. Mosquitoes were challenged using the membrane-feeding assay technique and were tested seven and fourteen days post-infection (early and late infection phases, respectively). The infection responses varied among the Ae. aegypti populations for both flaviviruses in the two infection phases. There was no similarity between DENV and ZIKV vector competencies or viral loads. According to the results of our study, the risk of viral transmission overtime after infection either increases or remains unaltered in ZIKV infected vectors. However, the risk may increase, decrease, or remain unaltered in DENV-infected vectors depending on the mosquito population. For both flaviviruses, the viral load persisted in the body even until the late infection phase. In contrast to DENV, the ZIKV accumulated in the SG over time in all the mosquito populations. These findings are novel and may help direct the development of control strategies to fight dengue and Zika outbreaks in endemic regions, and provide a warning about the importance of understanding mosquito responses to arboviral infections.


Assuntos
Aedes/virologia , Mosquitos Vetores/virologia , Zika virus/isolamento & purificação , Aedes/fisiologia , Animais , Brasil/epidemiologia , Doenças Endêmicas , Feminino , Humanos , Masculino , Mosquitos Vetores/fisiologia , Glândulas Salivares/virologia , Carga Viral , Zika virus/genética , Zika virus/fisiologia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
9.
Sci Rep ; 11(1): 21129, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702887

RESUMO

In the Americas, some mosquito-borne viruses such as Zika, chikungunya, and dengue circulate among humans in urban transmission cycles, while others, including yellow fever and Mayaro, circulate among monkeys in sylvatic cycles. The intersection of humans and wildlife at forest edges creates risk for zoonotic virus exchange. We built a scaffold tower at the edge of a treefall gap in rainforest bordering Manaus, Brazil, to identify vectors that may bridge transmission between humans and monkeys. We vertically sampled diurnally active, anthropophilic mosquitoes using handheld nets at 0, 5, and 9 m and container-breeding mosquitoes in ovitraps at 0, 5, 10, and 15 m. Haemagogus janthinomys and Psorophora amazonica were present in high relative abundance in nets at each height sampled, while anthropophilic species were uncommon in ovitraps. Hg. janthinomys was more abundant at elevated heights than at ground level, while Ps. amazonica abundance was not significantly stratified across heights. The presence of each species increased with increasing 7-day rainfall lagged at 1 week, and at 1 and 4 weeks prior to collection, respectively. In addition, Hg. janthinomys was most frequently collected at 29.9 °C, irrespective of height. These data provide insight into the potential role of each species as bridge vectors.


Assuntos
Arbovírus , Culicidae/virologia , Florestas , Microclima , Modelos Biológicos , Mosquitos Vetores/virologia , Animais , Arbovírus/classificação , Arbovírus/isolamento & purificação , Arbovírus/metabolismo , Brasil , Culicidae/fisiologia , Haplorrinos , Mosquitos Vetores/fisiologia
10.
Viruses ; 13(10)2021 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-34696363

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the agent of coronavirus disease 2019 (COVID-19), is responsible for the worst pandemic of the 21st century. Like all human coronaviruses, SARS-CoV-2 originated in a wildlife reservoir, most likely from bats. As SARS-CoV-2 has spread across the globe in humans, it has spilled over to infect a variety of non-human animal species in domestic, farm, and zoo settings. Additionally, a broad range of species, including one neotropical monkey, have proven to be susceptible to experimental infection with SARS-CoV-2. Together, these findings raise the specter of establishment of novel enzootic cycles of SARS-CoV-2. To assess the potential exposure of free-living non-human primates to SARS-CoV-2, we sampled 60 neotropical monkeys living in proximity to Manaus and São José do Rio Preto, two hotspots for COVID-19 in Brazil. Our molecular and serological tests detected no evidence of SAR-CoV-2 infection among these populations. While this result is reassuring, sustained surveillance efforts of wildlife living in close association with human populations is warranted, given the stochastic nature of spillover events and the enormous implications of SARS-CoV-2 spillover for human health.


Assuntos
COVID-19/epidemiologia , Monitoramento Epidemiológico/veterinária , Primatas/virologia , Alouatta/virologia , Animais , Animais Selvagens/virologia , Brasil/epidemiologia , COVID-19/veterinária , Callicebus/virologia , Callithrix/virologia , Pandemias , SARS-CoV-2/patogenicidade , Zoonoses Virais/transmissão
11.
J Infect Dis ; 224(1): 101-108, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-33544850

RESUMO

BACKGROUND: Aedes aegypti is a highly competent vector in the transmission of arboviruses, such as chikungunya, dengue, Zika, and yellow fever viruses, and causes single and coinfections in the populations of tropical countries. METHODS: The infection rate, viral abundance (VA), vector competence (VC), disseminated infection, and survival rate were recorded after single and multiple infections of the vector with 15 combinations of chikungunya, dengue, Zika, and yellow fever arboviruses. RESULTS: Infection rates were 100% in all single and multiple infection experiments, except in 1 triple coinfection that presented a rate of 50%. The VC and disseminated infection rate varied from 100% (in single and quadruple infections) to 40% (in dual and triple infections). The dual and triple coinfections altered the VC and/or VA of ≥1 arbovirus. The highest viral VAs were detected for a single infection with chikungunya. The VAs in quadruple infections were similar when compared with each respective single infection. A decrease in survival rates was observed in a few combinations. CONCLUSIONS: A. aegypti was able to host all single and multiple arboviral coinfections. The interference of the chikungunya virus suggests that distinct arbovirus families may have a significant role in complex coinfections.


Assuntos
Aedes/virologia , Infecções por Arbovirus/transmissão , Coinfecção/transmissão , Mosquitos Vetores/virologia , Animais , Arbovírus/isolamento & purificação , Feminino
12.
Acta Trop ; 215: 105819, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33406443

RESUMO

The outbreaks caused by the Aedes aegypti-transmitted dengue virus (DENV), zakat virus (ZIKV), and chikungunya virus (CHIKV) result in a significant impact to the health systems of tropical countries. Furthermore, the occurrence of patients coinfected by at least two of these arboviruses is an aggravating factor in that scenario. On this basis, surveillance tools such as the Rapid Index Survey for Aedes aegypti (LIRAa) are used to estimate vector infestation in order to improve the prediction of human outbreaks. Ae. aegypti eggs were collected in the city of Vitória da Conquista, in Bahia State, Brazil, and subsequently hatched into larvae, which were analyzed in pools or individually for the presence of DENV, ZIKV, and CHIKV by molecular biology methods. The detection data for arboviruses were crossed with the LIRAa obtained in each region of the study city. Thirty larvae pools were analyzed, and fourteen (46.6%) of them were detected positive for DENV, ZIKV, and/or CHIKV. Among the individually analyzed larvae (n = 30), nine (30%) were positive for any of these arboviruses, and four (13.3%) were simultaneously coinfected by DENV and ZIKV. Furthermore, there was a positive correlation between the detection of circulating arboviruses and LIRAa. The simultaneous Ae. aegypti larvae infection by two different arboviruses is an unprecedented finding. This result suggests the occurrence of a vertical arboviruses co-transmission from the female mosquito to its offspring in nature. The occurrence of concomitant circulation of DENV, ZIKV, and CHIKV in Ae. aegypti from a single study region is another finding of this article. Finally, LIRAa seems to not only estimate vector infestation but also to predict circulation of arboviruses.


Assuntos
Aedes/virologia , Vírus Chikungunya/isolamento & purificação , Coinfecção/transmissão , Vírus da Dengue/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas , Mosquitos Vetores/virologia , Zika virus/isolamento & purificação , Animais , Feminino , Humanos , Larva/virologia
13.
Viruses ; 14(1)2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-35062224

RESUMO

The successful spread and maintenance of the dengue virus (DENV) in mosquito vectors depends on their viral infection susceptibility, and parameters related to vector competence are the most valuable for measuring the risk of viral transmission by mosquitoes. These parameters may vary according to the viral serotype in circulation and in accordance with the geographic origin of the mosquito population that is being assessed. In this study, we investigated the effect of DENV serotypes (1-4) with regards to the infection susceptibility of five Brazilian Ae. aegypti populations from Manaus, the capital of the state of Amazonas, Brazil. Mosquitoes were challenged by oral infection with the DENV serotypes and then tested for the presence of the arbovirus using quantitative PCR at 14 days post-infection, which is the time point that corresponds to the extrinsic incubation period of Ae. aegypti when reared at 28 °C. Thus, we were able to determine the infection patterns for DENV-1, -2, -3 and -4 in the mosquito populations. The mosquitoes had both interpopulation and inter-serotype variation in their viral susceptibilities. All DENV serotypes showed a similar tendency to accumulate in the body in a greater amount than in the head/salivary gland (head/SG), which does not occur with other flaviviruses. For DENV-1, DENV-3, and DENV-4, the body viral load varied among populations, but the head/SG viral loads were similar. Differently for DENV-2, both body and head/SG viral loads varied among populations. As the lack of phenotypic homogeneity represents one of the most important reasons for the long-term fight against dengue incidence, we expect that this study will help us to understand the dynamics of the infection patterns that are triggered by the distinct serotypes of DENV in mosquitoes.


Assuntos
Aedes/virologia , Vírus da Dengue/fisiologia , Mosquitos Vetores/virologia , Animais , Brasil , Vírus da Dengue/genética , Feminino , Sorogrupo , Carga Viral
14.
Viruses, v. 13, n. 10, 1933, set. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4035

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the agent of coronavirus disease 2019 (COVID-19), is responsible for the worst pandemic of the 21st century. Like all human coronaviruses, SARS-CoV-2 originated in a wildlife reservoir, most likely from bats. As SARS-CoV-2 has spread across the globe in humans, it has spilled over to infect a variety of non-human animal species in domestic, farm, and zoo settings. Additionally, a broad range of species, including one neotropical monkey, have proven to be susceptible to experimental infection with SARS-CoV-2. Together, these findings raise the specter of establishment of novel enzootic cycles of SARS-CoV-2. To assess the potential exposure of free-living non-human primates to SARS-CoV-2, we sampled 60 neotropical monkeys living in proximity to Manaus and São José do Rio Preto, two hotspots for COVID-19 in Brazil. Our molecular and serological tests detected no evidence of SAR-CoV-2 infection among these populations. While this result is reassuring, sustained surveillance efforts of wildlife living in close association with human populations is warranted, given the stochastic nature of spillover events and the enormous implications of SARS-CoV-2 spillover for human health.

15.
Acta Trop ; 206: 105441, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32173316

RESUMO

Mosquito-borne Zika virus (ZIKV) was recently introduced into the Americas and now has the potential to spill back into a sylvatic cycle in the region, likely involving non-human primates and Aedes, Haemagogus, and Sabethes species mosquitoes. We investigated potential routes of mosquito-borne virus exchange between urban and sylvatic transmission cycles by characterizing mosquito communities in three urban forest parks that receive heavy traffic from both humans and monkeys in Manaus, Brazil. Parks were stratified by both distance from the urban-forest edge (0, 50, 100, and 500 m) and relative Normalized Difference Vegetation Index (NDVI) (low, medium, or high), and mosquitoes were sampled at randomly selected sites within each stratum using BG-Sentinel traps. Additionally, temperature, relative humidity, and other environmental data were collected at each site. A total of 1,172 mosquitoes were collected from 184 sites sampled in 2018, of which 98 sites were resampled in 2019. Using park as the unit of replication (i.e. 3 replicates per sampling stratum), a two-way ANOVA showed no effect of distance or NDVI on the mean number of identified species (P > 0.05 for both comparisons) or on species diversity as measured by the Shannon-Wiener diversity index (P > 0.10 for both comparisons). However, the Morisita overlap index revealed that mosquito communities changed substantially with increasing distance from edge, with communities at 0 m and 500 m being quite distinct. Aedes albopictus and Ae. aegypti penetrated at least 100 m into the forest, while forest specialists including Haemagogus janthinomys, Sabethes glaucodaemon, and Sa. tridentatus were detected in low numbers within 100 m from the forest edge. Trichoprosopon digitatum and Psorophora amazonica were among the most abundant species collected, and both showed distributions extending from the forest edge to its interior. Our results show overlapping distributions of urban and forest mosquitoes at park edges, which highlights the risk of arbovirus exchange via multiple bridge vectors in Brazilian urban forest parks. These parks may also provide refugia for both Ae. albopictus and Ae. aegypti from mosquito control programs.


Assuntos
Culicidae , Florestas , Mosquitos Vetores , Infecção por Zika virus/transmissão , Animais , Brasil , Culicidae/virologia , Demografia , Humanos , Controle de Mosquitos , Mosquitos Vetores/virologia , Parques Recreativos , Zika virus/isolamento & purificação
16.
J Med Entomol ; 56(6): 1739-1744, 2019 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-31278737

RESUMO

Zika virus (ZIKV) has emerged as a globally important arbovirus and has been reported from all states of Brazil. The virus is primarily transmitted to humans through the bite of an infective Aedes aegypti (Linnaeus, 1762) or Aedes albopictus (Skuse, 1895). However, it is important to know if ZIKV transmission also occurs from Ae. aegypti through infected eggs to her offspring. Therefore, a ZIKV and dengue virus (DENV) free colony was established from eggs collected in Manaus and maintained until the third-fourth generation in order to conduct ZIKV vertical transmission (VT) experiments which used an infectious bloodmeal as the route of virus exposure. The eggs from ZIKV-infected females were allowed to hatch. The resulting F1 progeny (larvae, pupae, and adults) were quantitative polymerase chain reaction (qPCR) assayed for ZIKV. The viability of ZIKV vertically transmitted to F1 progeny was evaluated by cultivation in C6/36 cells. The effects of ZIKV on immature development of Ae. aegypti was assessed and compared with noninfected mosquitoes. AmazonianAe. aegypti were highly susceptible to ZIKV infection (96.7%), and viable virus passed to their progeny via VT. Moreover, eggs from the ZIKV-infected mosquitoes had a significantly lower hatch rate and the slowest hatching. In addition, the larval development period was slower when compared to noninfected, control mosquitoes. This is the first study to illustrate VT initiated by oral infection of the parental population by using mosquitoes, which originated from the field and a ZIKV strain that is naturally circulating in-country. Additionally, this study suggests that ZIKV present in the Ae. aegypti can modify the mosquito life cycle. The data reported here suggest that VT of ZIKV to progeny from naturally infected females may have a critical epidemiological role in the dissemination and maintenance of the virus circulating in the vector.


Assuntos
Aedes/crescimento & desenvolvimento , Aedes/virologia , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/virologia , Zika virus/fisiologia , Animais , Brasil , Feminino , Larva/crescimento & desenvolvimento , Larva/virologia , Óvulo/crescimento & desenvolvimento , Óvulo/virologia
17.
PLoS Negl Trop Dis ; 12(5): e0006525, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29813061

RESUMO

The dynamics of dengue virus (DENV) circulation depends on serotype, genotype and lineage replacement and turnover. In São José do Rio Preto, Brazil, we observed that the L6 lineage of DENV-1 (genotype V) remained the dominant circulating lineage even after the introduction of the L1 lineage. We investigated viral fitness and immunogenicity of the L1 and L6 lineages and which factors interfered with the dynamics of DENV epidemics. The results showed a more efficient replicative fitness of L1 over L6 in mosquitoes and in human and non-human primate cell lines. Infections by the L6 lineage were associated with reduced antigenicity, weak B and T cell stimulation and weak host immune system interactions, which were associated with higher viremia. Our data, therefore, demonstrate that reduced viral immunogenicity and consequent greater viremia determined the increased epidemiological fitness of DENV-1 L6 lineage in São José do Rio Preto.


Assuntos
Vírus da Dengue/imunologia , Dengue/imunologia , Aedes/fisiologia , Aedes/virologia , Animais , Linfócitos B/imunologia , Brasil , Estudos de Coortes , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/classificação , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Genótipo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Filogenia , Linfócitos T/imunologia
18.
J Infect Dis ; 218(4): 563-571, 2018 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-29659904

RESUMO

Background: Several tropical cities are permissive to Aedes aegypti and dengue virus (DENV) endemicity and have allowed for invasion and circulation of Zika virus (ZIKV) in the same areas. People living in arbovirus-endemic regions have been simultaneously infected with ≥2 arboviruses. Methods: A. aegypti mosquitoes from Manaus, the capital city of Amazonas State in Brazil, were coinfected with circulating strains of DENV and ZIKV. The coinfected vectors were allowed to bite BALB/c mice. Results: A. aegypti from Manaus is highly permissive to monoinfection and coinfection with DENV and ZIKV and is capable of cotransmitting both pathogens by bite. Coinfection strongly influences vector competence, favoring transmission of ZIKV to the vertebrate host. Conclusions: This finding suggests that A. aegypti is an efficient vector of ZIKV and that ZIKV would be preferentially transmitted by coinfected A. aegypti. Coinfection in the vector population should be considered a new critical epidemiological factor and may represent a major public health challenge.


Assuntos
Aedes/virologia , Coinfecção/transmissão , Dengue/transmissão , Transmissão de Doença Infecciosa , Mosquitos Vetores/virologia , Infecção por Zika virus/transmissão , Aedes/crescimento & desenvolvimento , Animais , Brasil , Cidades , Vírus da Dengue/crescimento & desenvolvimento , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos BALB C , Mosquitos Vetores/crescimento & desenvolvimento , Zika virus/crescimento & desenvolvimento
19.
Rev Soc Bras Med Trop ; 51(1): 80-84, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29513849

RESUMO

INTRODUCTION: Hymenoptera injuries are commonly caused by stinging insects. In Amazonas state, Brazil, there is no information regarding distribution, profile, and systemic manifestations associated with Hymenoptera injuries. METHODS: This study aimed to identify risk factors for systemic manifestation using the Brazilian Notifiable Diseases Surveillance System (2007 to 2015). RESULTS: Half of Hymenoptera injuries were caused by bee stings. Hymenoptera injuries were concentrated in Manaus, and 13.36% of cases displayed systemic signs. Delayed medical assistance (4 to 12 hours) presented four times more risk for systemic manifestations. CONCLUSIONS: Simple clinical observations and history of injury are critical information for prognostic improvement.


Assuntos
Himenópteros/classificação , Mordeduras e Picadas de Insetos/epidemiologia , Adolescente , Adulto , Animais , Abelhas , Brasil/epidemiologia , Criança , Notificação de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
20.
Rev. Soc. Bras. Med. Trop ; 51(1): 80-84, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1041440

RESUMO

Abstract INTRODUCTION: Hymenoptera injuries are commonly caused by stinging insects. In Amazonas state, Brazil, there is no information regarding distribution, profile, and systemic manifestations associated with Hymenoptera injuries. METHODS: This study aimed to identify risk factors for systemic manifestation using the Brazilian Notifiable Diseases Surveillance System (2007 to 2015). RESULTS: Half of Hymenoptera injuries were caused by bee stings. Hymenoptera injuries were concentrated in Manaus, and 13.36% of cases displayed systemic signs. Delayed medical assistance (4 to 12 hours) presented four times more risk for systemic manifestations. CONCLUSIONS: Simple clinical observations and history of injury are critical information for prognostic improvement.


Assuntos
Humanos , Animais , Masculino , Feminino , Criança , Adolescente , Adulto , Adulto Jovem , Himenópteros/classificação , Mordeduras e Picadas de Insetos/epidemiologia , Abelhas , Brasil/epidemiologia , Fatores de Risco , Notificação de Doenças , Pessoa de Meia-Idade
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