RESUMO
We tested 294 domestic pet dogs in Mexico for neutralizing antibodies for mosquito-borne flaviviruses. We found high (42.6%) exposure to West Nile virus in Reynosa (northern Mexico) and low (1.2%) exposure in Tuxtla Gutierrez (southern Mexico) but very limited exposure to Aedes-borne flaviviruses. Domestic dogs may be useful sentinels for West Nile virus.
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Aedes , Culicidae , Flavivirus , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Anticorpos Neutralizantes , Cães , México/epidemiologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterináriaRESUMO
Newcastle disease, one of the most important health problems that affects the poultry industry around the world, is caused by virulent strains of Newcastle disease virus. Newcastle disease virus is considered to be endemic in several countries in the Americas, including Mexico. In order to control Newcastle disease outbreaks and spread, intensive vaccination programs, which include vaccines formulated with strains isolated at least 60 years ago, have been established. These vaccines are dissimilar in genotype to the virulent Newcastle disease viruses that had been circulating in Mexico until 2008. Here, 28 isolates obtained between 2008 and 2011 from different regions of Mexico from free-living wild birds, captive wild birds, and poultry were phylogenetically and biologically characterized in order to study the recent epidemiology of Newcastle disease viruses in Mexico. Here we demonstrate that, until recently, virulent viruses from genotype V continued to circulate and evolve in the country. All of the Newcastle disease viruses of low virulence, mostly isolated from nonvaccinated free-living wild birds and captive wild birds, were highly similar to LaSota (genotype II) and PHY-LMV42 (genotype I) vaccine strains. These findings, together with the discovery of two virulent viruses at the Mexican zoo, suggest that Newcastle disease viruses may be escaping from poultry into the environment.
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Aves , Galinhas , Doença de Newcastle/epidemiologia , Vírus da Doença de Newcastle/genética , Doenças das Aves Domésticas/epidemiologia , Animais , Aves/classificação , Genótipo , México/epidemiologia , Epidemiologia Molecular , Dados de Sequência Molecular , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/isolamento & purificação , Vírus da Doença de Newcastle/patogenicidade , Vírus da Doença de Newcastle/fisiologia , Filogenia , Reação em Cadeia da Polimerase , Doenças das Aves Domésticas/virologia , RNA Viral/genética , RNA Viral/metabolismo , Análise de Sequência de RNA/veterinária , Homologia de Sequência , VirulênciaRESUMO
SARS-CoV-2 mainly affects humans; however, it is important to monitor the infection of companion and wild animals as possible reservoirs of this virus. In this sense, seroprevalence studies in companion animals, such as dogs and cats, provide important information about the epidemiology of SARS-CoV-2. This study aimed to evaluate the seroprevalence of neutralizing antibodies (nAbs) against the ancestral strain and the Omicron BA.1 subvariant in dogs and cats in Mexico. Six hundred and two samples were obtained from dogs (n = 574) and cats (n = 28). These samples were collected from the end of 2020 to December 2021 from different regions of Mexico. The presence of nAbs was evaluated using a plaque reduction neutralization test (PRNT) and microneutralization (MN) assays. The results showed that 14.2% of cats and 1.5% of dogs presented nAbs against the ancestral strain of SARS-CoV-2. The analysis of nAbs against Omicron BA.1 in cats showed the same percentage of positive animals but a reduced titer. In dogs, 1.2% showed nAbs against Omicron BA.1. These results indicate that nAbs were more frequent in cats than in dogs and that these nAbs have a lower capacity to neutralize the subvariant Omicron BA.1.
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SARS-CoV-2 can infect pets under natural conditions, which raises questions about the risk factors related to the susceptibility of these animals to infection. The status of pet infection by SARS-CoV-2 in Mexico is not well-understood. We aimed to estimate the frequency of positive household cats and dogs to viral RNA and antibodies for SARS-CoV-2 during the second wave of human infections in Mexico, and to recognize the major risk factors related to host and pet ownership behaviour. We evaluated two study groups, cats and dogs from COVID-19-infected/-suspected households (n = 44) and those admitted for veterinary care for any reason at several veterinary hospitals in Puebla City, Mexico (n = 91). Using RT-PCR, we identified the presence of SARS-CoV-2 RNA in swabs of four dogs (18.18%) and zero cats in COVID-19-infected/-suspected households; within this group, 31.82% of dogs and 27.27% of cats were tested IgG ELISA-positive; and neutralizing antibodies were detected in one dog (4.55%) and two cats (9.09%). In the random group (pets evaluated at private clinics and veterinary teaching hospital), 25.00% of dogs and 43.59% of cats were ELISA-positive and only one cat showed neutralizing antibodies (2.56%). Older than 4-year-old, other pets at home, and daily cleaning of pet dish, were each associated with an increase in SARS-CoV-2 infection (p < 0.05). Allowing face lick, sharing bed/food with pets and owner tested positive or suspected COVID-19 were not significant risk factors, but more than 4 h the owner spent away from home during the lockdown for COVID-19 (OR = 0.37, p = 0.01), and outdoor pet food tray (OR = 0.32, p = 0.01) significantly decreased the risks of SARS-CoV-2 infection in pets, suggesting that time the owner spends with their pet is an important risk factor.
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COVID-19 , Doenças do Gato , Doenças do Cão , Animais , Gatos , Humanos , Cães , COVID-19/epidemiologia , COVID-19/veterinária , SARS-CoV-2 , Propriedade , México/epidemiologia , Hospitais Veterinários , RNA Viral , Controle de Doenças Transmissíveis , Hospitais de Ensino , Anticorpos Neutralizantes , Fatores de Risco , Animais de Estimação , Doenças do Gato/epidemiologia , Doenças do Cão/epidemiologiaRESUMO
The Mexican lineage H7N3 highly pathogenic avian influenza virus (HPAIV) has persisted in Mexican poultry since its first isolation in 2012. To date, the detection of this virus has gradually expanded from the initial one state to 18 states in Mexico. Despite the HPAIV H7N3 outbreak occurring yearly, the transmission pathways have never been studied, disallowing the establishment of effective control measures. We used a phylogenetic approach to unravel the transmission pathways of 2022 H7N3 HPAIVs in the new outbreak areas in Northern Mexico. We present genetic data of H7N3 viruses produced from 18 poultry farms infected in the spring of 2022. Our results indicate that the virus responsible for the current outbreak in Northern Mexico evolved from the Mexican lineage H7N3 HPAIV discovered in 2012. In the current outbreak, we identified five clusters of infection with four noticeably different genetic backgrounds. It is a cluster IV-like virus that was transmitted into one northern state causing an outbreak, then spreading to another neighboring northern state, possibly via a human-mediated mechanical transmission mechanism. The long-distance transmission event highlights the necessity for the more rigorous enforcement of biosafety measures in outbreaks. Additionally, we examined the evolutionary processes shaping the viral genetic and antigenic diversities. It is imperative to enhance active surveillance to include birds, the environment, and humans to detect HPAI in domestic poultry at an earlier point and eliminate it.
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Here, we report three near-full-length genome sequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) obtained in Mexico City, Mexico, during the pandemic of coronavirus disease 19 (COVID-19) in 2020, representing a zooanthroponotic transmission event between humans and a dog. All three genomes belong to the B.1.189 lineage based on the pangolin classification.
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We have demonstrated for the first time a comprehensive evolutionary analysis of the Mexican lineage H5N2 avian influenza virus (AIV) using complete genome sequences (n = 189), from its first isolation in 1993 until 2019. Our study showed that the Mexican lineage H5N2 AIV originated from the North American wild bird gene pool viruses around 1990 and is currently circulating in poultry populations of Mexico, the Dominican Republic, and Taiwan. Since the implementation of vaccination in 1995, the highly pathogenic AIV (HPAIV) H5N2 virus was eradicated from Mexican poultry in mid-1995. However, the low pathogenic AIV (LPAIV) H5N2 virus has continued to circulate in domestic poultry populations in Mexico, eventually evolving into five distinct clades. In the current study, we demonstrate that the evolution of Mexican lineage H5N2 AIVs involves gene reassortments and mutations gained over time. The current circulating Mexican lineage H5N2 AIVs are classified as LPAIV based on the amino acid sequences of the hemagglutinin (HA) protein cleavage site motif as well as the results of the intravenous pathogenicity index (IVPI). The immune pressure from vaccinations most likely has played a significant role in the positive selection of antigenic drift mutants within the Mexican H5N2 AIVs. Most of the identified substitutions in these viruses are located on the critical antigenic residues of the HA protein and as a result, might have contributed to vaccine failures. This study highlights and stresses the need for vaccine updates while emphasizing the importance of continued molecular monitoring of the HA protein for its antigenic changes compared to the vaccines used.
Assuntos
Vírus da Influenza A Subtipo H5N2 , Vírus da Influenza A , Influenza Aviária , Animais , Galinhas , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A/genética , México , Filogenia , Aves DomésticasRESUMO
OBJECTIVE: To estimate the time of seroconversion to the New Jersey serotype of vesicular stomatitis virus (VSNJV) in sentinel cattle of dairy herds located at high and low elevations in southern Mexico and to determine the factors associated with an increase in VSNJV transmission. ANIMALS: 471 dairy cattle in 4 free-ranging dairy herds located at high and low elevations in southern Mexico. PROCEDURES: Serum samples from all cattle were screened by use of serum neutralization (SN) tests for antibodies against VSNJV. Cattle with SN titers<1:20 were designated as sentinel cattle and tested every 10 weeks for seroconversion to VSNJV (SN titer≥1:80). A Cox proportional hazards regression model was used to compare the hazard for seroconversion between sentinel cattle located at high and low elevations and kept under similar management and nutritional conditions. RESULTS: Hazard of VSNJV seroconversion was significantly higher for sentinel cattle located at high elevations, compared with the hazard for sentinel cattle located at low elevations. Dairy cattle located at high elevations seroconverted to VSNJV more frequently during the rainy season and the beginning of the dry season. CONCLUSIONS AND CLINICAL RELEVANCE: Seroconversion to VSNJV was more likely in dairy cattle in southern Mexico located at high elevations than in dairy cattle located at low elevations. These findings should contribute to understanding the dynamics of VSNJV infection in endemic areas and should be useful in the design of effective preventive and control strategies to decrease the impact of future VSV incursions.
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Doenças dos Bovinos/virologia , Estomatite Vesicular/imunologia , Vírus da Estomatite Vesicular New Jersey/imunologia , Altitude , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Indústria de Laticínios , Feminino , Masculino , México/epidemiologia , Testes de Neutralização , New Jersey , Modelos de Riscos Proporcionais , Estomatite Vesicular/epidemiologiaRESUMO
Endemic circulation of foot-and-mouth disease (FMD) in Africa and Asia poses a continuous risk to countries in Europe, North America, and Oceania which are free from the disease. Introductions of the disease into a free region have dramatic economic impacts, especially if they are not detected at an early stage and controlled rapidly. However, farmers and veterinarians have an obvious disincentive to report clinical signs that are consistent with FMD, due to the severe consequences of raising an official suspicion, such as farm-level quarantine. One way that the risk of late detection can be mitigated is offering non-discriminatory exclusion testing schemes for differential diagnostics, wherein veterinarians can submit samples without the involvement of the competent authority and without sanctions or costs for the farmer. This review considers the benefits and limitations of this approach to improve the early detection of FMD in free countries and gives an overview of the FMD testing schemes currently in use in selected countries in Europe and the Americas as well as in Australia.
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In 1993, an outbreak of encephalitis among 125 affected equids in coastal Chiapas, Mexico, resulted in a 50% case-fatality rate. The outbreak was attributed to Venezuelan equine encephalitis virus (VEEV) subtype IE, not previously associated with equine disease and death. To better understand the ecology of this VEEV strain in Chiapas, we experimentally infected 5 species of wild rodents and evaluated their competence as reservoir and amplifying hosts. Rodents from 1 species (Baiomys musculus) showed signs of disease and died by day 8 postinoculation. Rodents from the 4 other species (Liomys salvini, Oligoryzomys fulvescens, Oryzomys couesi, and Sigmodon hispidus) became viremic but survived and developed neutralizing antibodies, indicating that multiple species may contribute to VEEV maintenance. By infecting numerous rodent species and producing adequate viremia, VEEV may increase its chances of long-term persistence in nature and could increase risk for establishment in disease-endemic areas and amplification outside the disease-endemic range.
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Doenças Transmissíveis Emergentes/veterinária , Vírus da Encefalite Equina Venezuelana/patogenicidade , Encefalomielite Equina Venezuelana/veterinária , Doenças dos Cavalos/transmissão , Animais , Animais Selvagens/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/virologia , Surtos de Doenças/veterinária , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , Ecossistema , Encefalomielite Equina Venezuelana/epidemiologia , Encefalomielite Equina Venezuelana/transmissão , Encefalomielite Equina Venezuelana/virologia , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/virologia , Cavalos , México/epidemiologia , Roedores/virologia , Viremia/imunologia , Viremia/veterináriaRESUMO
Venezuelan equine encephalitis virus (VEEV) has been the causative agent for sporadic epidemics and equine epizootics throughout the Americas since the 1930s. In 1969, an outbreak of Venezuelan equine encephalitis (VEE) spread rapidly from Guatemala and through the Gulf Coast region of Mexico, reaching Texas in 1971. Since this outbreak, there have been very few studies to determine the northward extent of endemic VEEV in this region. This study reports the findings of serologic surveillance in the Gulf Coast region of Mexico from 2003-2010. Phylogenetic analysis was also performed on viral isolates from this region to determine whether there have been substantial genetic changes in VEEV since the 1960s. Based on the findings of this study, the Gulf Coast lineage of subtype IE VEEV continues to actively circulate in this region of Mexico and appears to be responsible for infection of humans and animals throughout this region, including the northern State of Tamaulipas, which borders Texas.
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Vírus da Encefalite Equina Venezuelana/isolamento & purificação , Encefalomielite Equina Venezuelana/epidemiologia , Doenças Endêmicas , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Estudos Soroepidemiológicos , Adulto JovemRESUMO
Venezuelan equine encephalitis (VEE) is an emerging infectious disease in Latin America. Outbreaks have been recorded for decades in countries with enzootic circulation, and the recent implementation of surveillance systems has allowed the detection of additional human cases in countries and areas with previously unknown VEE activity. Clinically, VEE is indistinguishable from dengue and other arboviral diseases and confirmatory diagnosis requires the use of specialized laboratory tests that are difficult to afford in resource-limited regions. Thus, the disease burden of endemic VEE in developing countries remains largely unknown, but recent surveillance suggests that it may represent up to 10% of the dengue burden in neotropical cities, or tens-of-thousands of cases per year throughout Latin America. The potential emergence of epizootic viruses from enzootic progenitors further highlights the need to strengthen surveillance activities, identify mosquito vectors and reservoirs and develop effective strategies to control the disease. In this article, we provide an overview of the current status of endemic VEE that results from spillover of the enzootic cycles, and we discuss public health measures for disease control as well as future avenues for VEE research.
RESUMO
Enzootic Venezuelan equine encephalitis virus (VEEV) has been known to occur in Mexico since the 1960s. The first natural equine epizootic was recognized in Chiapas in 1993 and since then, numerous studies have characterized the etiologic strains, including reverse genetic studies that incriminated a specific mutation that enhanced infection of epizootic mosquito vectors. The aim of this study was to determine the mosquito and rodent species involved in enzootic maintenance of subtype IE VEEV in coastal Chiapas. A longitudinal study was conducted over a year to discern which species and habitats could be associated with VEEV circulation. Antibody was rarely detected in mammals and virus was not isolated from mosquitoes. Additionally, Culex (Melanoconion) taeniopus populations were found to be spatially related to high levels of human and bovine seroprevalence. These mosquito populations were concentrated in areas that appear to represent foci of stable, enzootic VEEV circulation.
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Culicidae/virologia , Vetores de Doenças , Vírus da Encefalite Equina Venezuelana/fisiologia , Encefalomielite Equina Venezuelana/transmissão , Insetos Vetores/virologia , Roedores/virologia , Aedes/virologia , Animais , Animais Selvagens/virologia , Anticorpos Antivirais/imunologia , Bovinos/virologia , Doenças dos Bovinos/virologia , Cricetinae/virologia , Culex/virologia , Encefalomielite Equina Venezuelana/virologia , Humanos , Estudos Longitudinais , México , Estações do Ano , Sigmodontinae/virologiaRESUMO
Coues rice rat (Oryzomys couesi), a species abundant throughout Central America, was evaluated experimentally for the ability to serve as an amplifying host for three arboviruses: Patois (Bunyaviridae, Orthobunyavirus), Nepuyo (Orthobunyavirus), and Venezuelan equine encephalitis virus subtype ID (Togaviridae, Alphavirus). These three viruses have similar ecologies and are known to co-circulate in nature. Animals from all three cohorts survived infection and developed viremia with no apparent signs of illness and long-lasting antibodies. Thus, O. couesi may play a role in the general maintenance of these viruses in nature.
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Infecções por Arbovirus/virologia , Arbovírus/patogenicidade , Sigmodontinae , Animais , Anticorpos Antivirais/sangue , Infecções por Arbovirus/imunologia , Testes de Inibição da Hemaglutinação , MéxicoRESUMO
Complete genome sequencing of 22 West Nile virus isolates suggested 2 independent introductions into Mexico. A previously identified mouse-attenuated glycosylation variant was introduced into southern Mexico through the southeastern United States, while a common US genotype appears to have been introduced incrementally into northern Mexico through the southwestern United States.
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Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/virologia , Aves/classificação , Aves/virologia , Corvos/virologia , Culex/virologia , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/virologia , Cavalos/virologia , Humanos , México/epidemiologia , Camundongos , Dados de Sequência Molecular , Análise de Sequência de DNA , Estados Unidos , Virulência , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/classificação , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/patogenicidadeRESUMO
In 1993 and 1996, subtype IE Venezuelan equine encephalitis (VEE) virus caused epizootics in the Mexican states of Chiapas and Oaxaca. Previously, only subtype IAB and IC VEE virus strains had been associated with major outbreaks of equine and human disease. The IAB and IC epizootics are believed to emerge via adaptation of enzootic (sylvatic, equine-avirulent) strains for high titer equine viremia that results in efficient infection of mosquito vectors. However, experimental equine infections with subtype IE equine isolates from the Mexican outbreaks demonstrated neuro-virulence but little viremia, inconsistent with typical VEE emergence mechanisms. Therefore, we hypothesized that changes in the mosquito vector host range might have contributed to the Mexican emergence. To test this hypothesis, we evaluated the susceptibility of the most abundant mosquito in the deforested Pacific coastal locations of the VEE outbreaks and a proven epizootic vector, Ochlerotatus taeniorhynchus. The Mexican epizootic equine isolates exhibited significantly greater infectivity compared with closely related enzootic strains, supporting the hypothesis that adaptation to an efficient epizootic vector contributed to disease emergence. Reverse genetic studies implicated a Ser --> Asn substitution in the E2 envelope glycoprotein as the major determinant of the increased vector infectivity phenotype. Our findings underscore the capacity of RNA viruses to alter their vector host range through minor genetic changes, resulting in the potential for disease emergence.
Assuntos
Vírus da Encefalite Equina Venezuelana/genética , Encefalomielite Equina Venezuelana/transmissão , Encefalomielite Equina Venezuelana/virologia , Ochlerotatus/virologia , Proteínas do Envelope Viral/genética , Substituição de Aminoácidos , Animais , Chlorocebus aethiops , Cricetinae , DNA Complementar , Vírus da Encefalite Equina Venezuelana/patogenicidade , Cavalos , Proteínas Recombinantes de Fusão/genética , Células Vero , VirulênciaRESUMO
The complete genome sequence of a Mexican West Nile virus isolate, TM171-03, included 46 nucleotide (0.42%) and 4 amino acid (0.11%) differences from the NY99 prototype. Mouse virulence differences between plaque-purified variants of TM171-03 with mutations at the E protein glycosylation motif suggest the emergence of an attenuating mutation.
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Genoma Viral , Vírus do Nilo Ocidental/genética , Animais , Sequência de Bases , Feminino , México , Camundongos , Mutação , Virulência/genética , Vírus do Nilo Ocidental/patogenicidadeRESUMO
Equine epizootics of Venezuelan equine encephalitis (VEE) occurred in the southern Mexican states of Chiapas in 1993 and Oaxaca in 1996. To assess the impact of continuing circulation of VEE virus (VEEV) on human and animal populations, serologic and viral isolation studies were conducted in 2000 to 2001 in Chiapas State. Human serosurveys and risk analyses indicated that long-term endemic transmission of VEEV occurred among villages with seroprevalence levels of 18% to 75% and that medical personnel had a high risk for VEEV exposure. Seroprevalence in wild animals suggested cotton rats as possible reservoir hosts in the region. Virus isolations from sentinel animals and genetic characterizations of these strains indicated continuing circulation of a subtype IE genotype, which was isolated from equines during the recent VEE outbreaks. These data indicate long-term enzootic and endemic VEEV circulation in the region and continued risk for disease in equines and humans.
Assuntos
Encefalomielite Equina Venezuelana/epidemiologia , Animais , Animais Selvagens/virologia , Vírus da Encefalite Equina Venezuelana/genética , Vírus da Encefalite Equina Venezuelana/isolamento & purificação , Encefalomielite Equina Venezuelana/veterinária , Genoma Viral , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/virologia , Cavalos , Humanos , México/epidemiologia , Filogenia , RNA Viral , Fatores de Risco , Vigilância de Evento Sentinela , Estudos SoroepidemiológicosRESUMO
West Nile virus (WNV) antibodies were detected in horses from five Mexican states, and WNV was isolated from a Common Raven in the state of Tabasco. Phylogenetic studies indicate that this isolate, the first from Mexico, is related to strains from the central United States but has a relatively high degree of sequence divergence.