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1.
J Infect Dev Ctries ; 13(4): 342-347, 2019 04 30.
Article in English | MEDLINE | ID: mdl-32045379

ABSTRACT

INTRODUCTION: Approximately 60% of emerging pathogens originate from wild animals, with mammals being the main hosts. Among Didelphis, which are restricted to the Americas, the species Didelphis aurita and Didelphis albiventris are particularly widely distributed throughout Brazil, where they act as hosts for several pathogens transmissible to humans. The reduction of their natural habitat has resulted in the adaptation of these species to human environments. Animals hunting, due to food necessity or cultural habit, may increase pathogen exposure with a potential to zoonotic disease transmission. METHODOLOGY: From November to December 2016, we administered semi-structured questionnaires in a rural community in northeastern Brazil to assess knowledge, practices and perceptions regarding human-didelphis interactions and possible exposure to zoonoses. RESULTS: There were 213 respondents. Based on photographs of D. albiventris and D. aurita, 91.2% and 78% respondents, respectively, identified the animal by the popular name "sariguê", 61% (130/213) believed the animal could convey any disease, 4.7% stated they did not, and 34% did not know. Opossum meat consumption was reported by 20.2% (43/213), of which 58.1% admitted disease transmission possibility. Only 15.9% of respondents had a secondary or higher education level. The distribution of these frequencies is discussed according to the respondents educational level. CONCLUSIONS: The results reveal the need to carry out health educational activities, including better community knowledge regarding the possible exposure to pathogens due to marsupial consumption.


Subject(s)
Didelphis/growth & development , Disease Reservoirs , Disease Transmission, Infectious/prevention & control , Environmental Exposure , Health Knowledge, Attitudes, Practice , Zoonoses/prevention & control , Zoonoses/transmission , Adult , Animals , Brazil , Feeding Behavior , Female , Humans , Male , Rural Population , Surveys and Questionnaires
2.
J Virol ; 92(13)2018 07 01.
Article in English | MEDLINE | ID: mdl-29695421

ABSTRACT

The discovery of highly diverse nonprimate hepatoviruses illuminated the evolutionary origins of hepatitis A virus (HAV) ancestors in mammals other than primates. Marsupials are ancient mammals that diverged from other Eutheria during the Jurassic. Viruses from marsupials may thus provide important insight into virus evolution. To investigate Hepatovirus macroevolutionary patterns, we sampled 112 opossums in northeastern Brazil. A novel marsupial HAV (MHAV) in the Brazilian common opossum (Didelphis aurita) was detected by nested reverse transcription-PCR (RT-PCR). MHAV concentration in the liver was high, at 2.5 × 109 RNA copies/g, and at least 300-fold higher than those in other solid organs, suggesting hepatotropism. Hepatovirus seroprevalence in D. aurita was 26.6% as determined using an enzyme-linked immunosorbent assay (ELISA). Endpoint titers in confirmatory immunofluorescence assays were high, and marsupial antibodies colocalized with anti-HAV control sera, suggesting specificity of serological detection and considerable antigenic relatedness between HAV and MHAV. MHAV showed all genomic hallmarks defining hepatoviruses, including late-domain motifs likely involved in quasi-envelope acquisition, a predicted C-terminal pX extension of VP1, strong avoidance of CpG dinucleotides, and a type 3 internal ribosomal entry site. Translated polyprotein gene sequence distances of at least 23.7% from other hepatoviruses suggested that MHAV represents a novel Hepatovirus species. Conserved predicted cleavage sites suggested similarities in polyprotein processing between HAV and MHAV. MHAV was nested within rodent hepatoviruses in phylogenetic reconstructions, suggesting an ancestral hepatovirus host switch from rodents into marsupials. Cophylogenetic reconciliations of host and hepatovirus phylogenies confirmed that host-independent macroevolutionary patterns shaped the phylogenetic relationships of extant hepatoviruses. Although marsupials are synanthropic and consumed as wild game in Brazil, HAV community protective immunity may limit the zoonotic potential of MHAV.IMPORTANCE Hepatitis A virus (HAV) is a ubiquitous cause of acute hepatitis in humans. Recent findings revealed the evolutionary origins of HAV and the genus Hepatovirus defined by HAV in mammals other than primates in general and in small mammals in particular. The factors shaping the genealogy of extant hepatoviruses are unclear. We sampled marsupials, one of the most ancient mammalian lineages, and identified a novel marsupial HAV (MHAV). The novel MHAV shared specific features with HAV, including hepatotropism, antigenicity, genome structure, and a common ancestor in phylogenetic reconstructions. Coevolutionary analyses revealed that host-independent evolutionary patterns contributed most to the current phylogeny of hepatoviruses and that MHAV was the most drastic example of a cross-order host switch of any hepatovirus observed so far. The divergence of marsupials from other mammals offers unique opportunities to investigate HAV species barriers and whether mechanisms of HAV immune control are evolutionarily conserved.


Subject(s)
Hepatitis A virus/classification , Liver/virology , Marsupialia/virology , Animals , Antibodies, Viral/metabolism , Brazil , Evolution, Molecular , Hepatitis A virus/genetics , Hepatitis A virus/physiology , Liver/immunology , Marsupialia/immunology , Phylogeny , Viral Proteins/chemistry , Viral Proteins/genetics , Viral Tropism
3.
mSphere ; 3(1)2018.
Article in English | MEDLINE | ID: mdl-29404420

ABSTRACT

Chikungunya virus (CHIKV) and Zika virus (ZIKV) emerged in the Americas in 2013. Limited antigenic variability of CHIKV and ZIKV may restrict urban transmission cycles due to population protective immunity. In Africa, sylvatic transmission cycles involving nonhuman primates (NHP) are known for CHIKV and ZIKV, causing cyclic reemergence in humans. To evaluate whether sylvatic cycles can be expected in Latin America, we tested 207 NHP collected between 2012 and 2017 in urban and peri-urban settings in Brazil for infection with ZIKV and CHIKV. No animal tested positive for viral RNA in genus-specific and species-specific reverse transcription-PCR (RT-PCR) assays. In contrast, six animals (2.9%) from the families Atelidae, Callitrichidae, and Cebidae showed ZIKV-specific antibodies and 11 (5.3%) showed CHIKV-specific antibodies in plaque reduction neutralization tests (PRNT). Reactivity was monotypic against either ZIKV or CHIKV in all cases, opposing unspecific virucidal activity of sera. PRNT endpoint titers were low at 1:40 in all NHP, and positive specimens did not correspond to the likely dispersal route and time of introduction of both arboviruses. All antibody-positive samples were therefore tested against the NHP-associated yellow fever virus (YFV) and Mayaro virus (MAYV) and against the human-associated dengue virus (DENV) by PRNT. Two ZIKV-positive samples were simultaneously DENV positive and two CHIKV-positive samples were simultaneously MAYV positive, at titers of 1:40 to 1:160. This suggested cross-reactive antibodies against heterologous alphaviruses and flaviviruses in 24% of ZIKV-positive/CHIKV-positive sera. In sum, low seroprevalence, invariably low antibody titers, and the distribution of positive specimens call into question the capability of ZIKV and CHIKV to infect New World NHP and establish sylvatic transmission cycles. IMPORTANCE Since 2013, Zika virus (ZIKV) and chikungunya virus (CHIKV) have infected millions of people in the Americas via urban transmission cycles. Nonhuman primates (NHP) are involved in sylvatic transmission cycles maintaining ZIKV and CHIKV in the Old World. We tested NHP sampled during 2012 to 2017 in urban and peri-urban areas severely affected by ZIKV and CHIKV in Brazil. Seroprevalence and antibody titers were low for both viruses. Additionally, we found evidence for infection by heterologous viruses eliciting cross-reactive antibodies. Our data suggest that urban or peri-urban NHP are not easily infected by ZIKV and CHIKV despite intense local transmission. These data may imply that the ZIKV and CHIKV outbreaks in the Americas cannot be sustained in urban or peri-urban NHP once human population immunity limits urban transmission cycles. Investigation of diverse animals is urgently required to determine the fate of the ZIKV and CHIKV outbreaks in the Americas.

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