RESUMO
Serologic evidence of past infection with a Sin Nombre-like hantavirus(es) was demonstrated in 78 (40.4%) of 193 Indians living in western Paraguay and in 38 (17.1%) of 222 Indians inhabiting the Salta province of northern Argentina. In both populations seroprevalence increased with age, with the most striking increase occurring at 18 years of age in the Paraguayan population and at 35 years of age in the Salta population. The peak prevalences in both populations (66.6% and 44.0%, respectively) were seen in Indians > 53 years old. Although no sex difference was observed in the Paraguayan Indians, in the Salta population seroprevalence was greater in males than in females. Familiar clustering of the infection was observed. The data indicate that the Indian populations of the Gran Chaco are frequently exposed to and survive infection with a Sin Nombre-like virus(es). Possible explanations of this novel epidemiology are discussed.
Assuntos
Anticorpos Antivirais/sangue , Infecções por Hantavirus/epidemiologia , Indígenas Sul-Americanos , Orthohantavírus/imunologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Argentina/epidemiologia , Western Blotting , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Immunoblotting , Masculino , Pessoa de Meia-Idade , Razão de Chances , Paraguai/epidemiologia , Prevalência , Distribuição por SexoRESUMO
OBJECTIVE: To determine whether animals had serologic evidence of infection with Sin Nombre virus (SNV). DESIGN: Prospective serosurvey. SAMPLE POPULATION: Serum samples were obtained from 145 cats, 85 dogs, 120 horses, and 24 cattle between April 1993 and August 1994 and 54 coyotes between December 1994 and February 1995. PROCEDURE: Serum samples were analyzed by western immunoblot assays for reaction with SNV nucleocapsid antigen. Samples with reactivity to SNV nucleocapsid proteins were used to probe multiple-antigen blots containing recombinant fusion proteins derived from prototypic hantaviruses. Lung tissue or blood clots were used in nested reverse-transcriptase polymerase chain reaction assays for a 320-nucleotide portion of the SNV G1 gene. RESULTS: Sera from 4 of 145 (2.8%) cats and 4 of 85 (3.5%) dogs had trace reactivity to full-length SNV-encoded nucleocapsid proteins. All samples from horses, cattle, and coyotes were nonreactive. Sera from cats and dogs that had trace IgG-antibody reactivity to nucleocapsid proteins were then tested for IgG-antibody reactivity to nucleocapsid proteins of prototypic hantaviruses. One cat had multiple cross-reactivities with these hantaviruses, consistent with exposure to a hantavirus; however, epitope mapping studies did not support this conclusion. Reverse-transcriptase polymerase chain reaction studies of blood clots or lung tissue from 2 animals that had weak reactivity to SNV failed to amplify any hantavirus sequence. CLINICAL IMPLICATIONS: Domestic animals, particularly dogs and cats, as well as coyotes do not appear to have a major role in the maintenance and transmission of SNV.
Assuntos
Animais Domésticos , Anticorpos Antivirais/sangue , Carnívoros , Infecções por Hantavirus/veterinária , Orthohantavírus/imunologia , Animais , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Arizona/epidemiologia , Western Blotting , Doenças do Gato/epidemiologia , Gatos , Bovinos , Doenças dos Bovinos/epidemiologia , Reações Cruzadas , Doenças do Cão/epidemiologia , Cães , Infecções por Hantavirus/epidemiologia , Doenças dos Cavalos/epidemiologia , Cavalos , Pulmão/virologia , New Mexico/epidemiologia , Proteínas do Nucleocapsídeo/imunologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , RNA Viral/análiseRESUMO
Human hantavirus disease occurs throughout much of South America. The rodent hosts and the specific etiologic agent(s) are largely unknown, but many reported cases occurred within the habitation ranges of oryzomine rodents (rice rats). We have identified a genetically novel hantavirus (Rio Mamore virus [RM]) of the pygmy rice rat Oligoryzomys microtis in Bolivia. The complete sequence of the small (S) genome and the partial sequence of the medium (M) genome are described. This virus is closely related to the newly identified human pathogen Andes virus from Patagonia. To facilitate improved diagnosis of hantavirus infections in South America, we have expressed the complete nucleocapsid protein of RM in Escherichia coli and affinity-purified it for use in an ELISA and Western blot assays for antibodies to RM.
Assuntos
Reservatórios de Doenças/veterinária , Genoma Viral , Orthohantavírus/classificação , Orthohantavírus/genética , Ratos/virologia , Sequência de Aminoácidos , Animais , Bolívia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da PolimeraseRESUMO
We recently described a novel hantavirus (HMV-1) of the western harvest mouse Reithrodontomys megalotis. Screening of 181 additional specimens of Reithrodontomys from the United States and Mexico, including samples of R. mexicanus, R. sumichrasti, and R. gracilis of Costa Rica, for antibodies to hantavirus nucleocapsid protein revealed a widespread enzootic of hantavirus infection. Genetic analyses of 7 S genomes of Reithrodontomys-associated hantaviruses demonstrated that the enzootic of HMV-1 extends from central Mexico into the southwestern United States. A presumed deer mouse hantavirus was found in an R. megalotis animal in Mexico. A highly divergent HMV-1-like virus, tentatively called HMV-2, was identified in a Costa Rican R. mexicanus. These data suggest a longstanding radiation of hantaviruses among New World harvest mice. We identify possible opportunities for genetic exchange among hantaviruses of related rodent hosts.