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1.
Am J Trop Med Hyg ; 107(4): 873-880, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096408

RESUMO

Zika virus (ZIKV) infections occurred in epidemic form in the Americas in 2014-2016, with some of the earliest isolates in the region coming from Haiti. We isolated ZIKV from 20 children with acute undifferentiated febrile illness who were part of a cohort of children seen at a school clinic in the Gressier region of Haiti. The virus was also isolated from three pools of Aedes aegypti mosquitoes collected at the same location. On phylogenetic analysis, three distinct ZIKV clades were identified. Strains from all three clades were present in Haiti in 2014, making them among the earliest isolates identified in the Western Hemisphere. Strains from all three clades were also isolated in 2016, indicative of their persistence across the time period of the epidemic. Mosquito isolates were collected in 2016 and included representatives from two of the three clades; in one instance, ZIKV was isolated from a pool of male mosquitoes, suggestive of vertical transmission of the virus. The identification of multiple ZIKV clades in Haiti at the beginning of the epidemic suggests that Haiti served as a nidus for transmission within the Caribbean.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Animais , Criança , Haiti/epidemiologia , Humanos , Masculino , Mosquitos Vetores , Filogenia , Instituições Acadêmicas
2.
Clin Infect Dis ; 75(1): e1184-e1187, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34718467

RESUMO

We isolated a novel coronavirus from a medical team member presenting with fever and malaise after travel to Haiti. The virus showed 99.4% similarity with a recombinant canine coronavirus recently identified in a pneumonia patient in Malaysia, suggesting that infection with this virus and/or recombinant variants occurs in multiple locations.


Assuntos
COVID-19 , Coronavirus Canino , Animais , Cães , Haiti , Humanos , SARS-CoV-2/genética , Viagem
3.
Nature ; 600(7887): 133-137, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34789872

RESUMO

Coronaviruses have caused three major epidemics since 2003, including the ongoing SARS-CoV-2 pandemic. In each case, the emergence of coronavirus in our species has been associated with zoonotic transmissions from animal reservoirs1,2, underscoring how prone such pathogens are to spill over and adapt to new species. Among the four recognized genera of the family Coronaviridae, human infections reported so far have been limited to alphacoronaviruses and betacoronaviruses3-5. Here we identify porcine deltacoronavirus strains in plasma samples of three Haitian children with acute undifferentiated febrile illness. Genomic and evolutionary analyses reveal that human infections were the result of at least two independent zoonoses of distinct viral lineages that acquired the same mutational signature in the genes encoding Nsp15 and the spike glycoprotein. In particular, structural analysis predicts that one of the changes in the spike S1 subunit, which contains the receptor-binding domain, may affect the flexibility of the protein and its binding to the host cell receptor. Our findings highlight the potential for evolutionary change and adaptation leading to human infections by coronaviruses outside of the previously recognized human-associated coronavirus groups, particularly in settings where there may be close human-animal contact.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Deltacoronavirus/isolamento & purificação , Suínos/virologia , Zoonoses Virais/epidemiologia , Zoonoses Virais/virologia , Sequência de Aminoácidos , Animais , Teorema de Bayes , Criança , Chlorocebus aethiops , Sequência Conservada , Infecções por Coronavirus/sangue , Deltacoronavirus/classificação , Deltacoronavirus/genética , Deltacoronavirus/patogenicidade , Feminino , Haiti/epidemiologia , Humanos , Masculino , Modelos Moleculares , Mutação , Filogenia , Células Vero , Zoonoses Virais/sangue
4.
medRxiv ; 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33791709

RESUMO

Coronaviruses have caused three major epidemics since 2003, including the ongoing SARS-CoV-2 pandemic. In each case, coronavirus emergence in our species has been associated with zoonotic transmissions from animal reservoirs 1,2 , underscoring how prone such pathogens are to spill over and adapt to new species. Among the four recognized genera of the family Coronaviridae - Alphacoronavirus, Betacoronavirus, Deltacoronavirus, Gammacoronavirus , - human infections reported to date have been limited to alpha- and betacoronaviruses 3 . We identify, for the first time, porcine deltacoronavirus (PDCoV) strains in plasma samples of three Haitian children with acute undifferentiated febrile illness. Genomic and evolutionary analyses reveal that human infections were the result of at least two independent zoonoses of distinct viral lineages that acquired the same mutational signature in the nsp15 and the spike glycoprotein genes by convergent evolution. In particular, structural analysis predicts that one of the changes in the Spike S1 subunit, which contains the receptor-binding domain, may affect protein's flexibility and binding to the host cell receptor. Our findings not only underscore the ability of deltacoronaviruses to adapt and potentially lead to human-to-human transmission, but also raise questions about the role of such transmissions in development of pre-existing immunity to other coronaviruses, such as SARS-CoV-2.

5.
Int J Health Geogr ; 20(1): 5, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33494756

RESUMO

BACKGROUND: The health burden in developing world informal settlements often coincides with a lack of spatial data that could be used to guide intervention strategies. Spatial video (SV) has proven to be a useful tool to collect environmental and social data at a granular scale, though the effort required to turn these spatially encoded video frames into maps limits sustainability and scalability. In this paper we explore the use of convolution neural networks (CNN) to solve this problem by automatically identifying disease related environmental risks in a series of SV collected from Haiti. Our objective is to determine the potential of machine learning in health risk mapping for these environments by assessing the challenges faced in adequately training the required classification models. RESULTS: We show that SV can be a suitable source for automatically identifying and extracting health risk features using machine learning. While well-defined objects such as drains, buckets, tires and animals can be efficiently classified, more amorphous masses such as trash or standing water are difficult to classify. Our results further show that variations in the number of image frames selected, the image resolution, and combinations of these can be used to improve the overall model performance. CONCLUSION: Machine learning in combination with spatial video can be used to automatically identify environmental risks associated with common health problems in informal settlements, though there are likely to be variations in the type of data needed for training based on location. Success based on the risk type being identified are also likely to vary geographically. However, we are confident in identifying a series of best practices for data collection, model training and performance in these settings. We also discuss the next step of testing these findings in other environments, and how adding in the simultaneously collected geographic data could be used to create an automatic health risk mapping tool.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Animais , Coleta de Dados , Haiti , Humanos , Fatores de Risco
6.
Artigo em Inglês | MEDLINE | ID: mdl-30841596

RESUMO

Diffusion of cholera and other diarrheal diseases in an informal settlement is a product of multiple behavioral, environmental and spatial risk factors. One of the most important components is the spatial interconnections among water points, drainage ditches, toilets and the intervening environment. This risk is also longitudinal and variable as water points fluctuate in relation to bacterial contamination. In this paper we consider part of this micro space complexity for three informal settlements in Port au Prince, Haiti. We expand on more typical epidemiological analysis of fecal coliforms at water points, drainage ditches and ocean sites by considering the importance of single point location fluctuation coupled with recording micro-space environmental conditions around each sample site. Results show that spatial variation in enteric disease risk occurs within neighborhoods, and that while certain trends are evident, the degree of individual site fluctuation should question the utility of both cross-sectional and more aggregate analysis. Various factors increase the counts of fecal coliform present, including the type of water point, how water was stored at that water point, and the proximity of the water point to local drainage. Some locations fluctuated considerably between being safe and unsafe on a monthly basis. Next steps to form a more comprehensive contextualized understanding of enteric disease risk in these environments should include the addition of behavioral factors and local insight.


Assuntos
Cólera/epidemiologia , Diarreia/epidemiologia , Cidades , Sistemas de Informação Geográfica , Haiti , Humanos , Fatores de Risco
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