Evidencia serológica de infección por hantavirus (Bunyaviridae: Hantavirus) en roedores del Departamento de Sucre, Colombia / Serological evidence of hanta virus infection (Bunyaviridae: Hantavirus) in rodents from the Sucre Department in Colombia

Objetivo Determinar la frecuencia de anticuerpos específicos a hantavirus en roedores del municipio de San Marcos, departamento de Sucre. Métodos Se capturaron 144 roedores con trampas Sherman® en áreas urbanas y rurales del municipio de San Marcos, desde diciembre de 2007 hasta julio de 2009. Los anticuerpos Ig G específicos contra el Virus Sin Nombre (VSN) fueron detectados en muestras de plasma mediante ELISA indirecto. Resultados La seroprevalencia de anticuerpos contra hantavirus fue del 8,3 % (12/144 capturas). Los porcentajes de seropositividad específicos por especie variaron entre 6,8 % (3/44, Zygodontomys brevicauda) y 50 % (1/2, Neacomys spinosus). No se encontró diferencia estadística en la seroprevalencia con respecto al área de muestreo, sexo y etapa reproductiva (p>0,05); sin embargo, hubo un mayor número de machos adultos seropositivos. Conclusiones Se evidenció por primera vez seropositividad a hantavirus en roedores de la subfamilia Murinae en Colombia. La detección de anticuerpos contra el virus refuerza la hipótesis que sugiere la circulación de al menos un hantavirus en roedores del norte colombiano.

Objective The main goal of this research was to determine the frequency of hantavirus-specific antibodies in rodents from the municipality of San Marcos in the Sucre department of Colombia. Methods 144 rodents were captured in San Marcos' urban and rural areas using Sherman traps between December 2007 and July 2009. "Virus sin Nombre" (SNV)-specific antibodies were detected in plasma samples by an indirect ELISA immunoassay. Results An 8.3 % (12/144) seroprevalence rate was found. Specific seropositivity rates ranged from 6.8 % (3/44, Zygodontomysbrevicauda) to 50 % (1/2, Neacomysspinosus). No significant differences were found in seroprevalence according to capture area, gender and/or reproductive stage (p>0.05); however, there were more seropositive adult males. Conclusion This is the first evidence of hanta virus seropositivity in rodents from the Murinae subfamily in Colombia. The presence of SNV antibodies in rodents in San Marcos supported the hypothesis that at least one hantavirusis circulating in rodents from northern Colombia.

[Serological evidence of hanta virus infection (Bunyaviridae: Hantavirus) in rodents from the Sucre Department in Colombia]. / Evidencia serológica de infección por hantavirus (Bunyaviridae: Hantavirus) en roedores del Departamento de Sucre, Colombia.

OBJECTIVE: The main goal of this research was to determine the frequency of hantavirus-specific antibodies in rodents from the municipality of San Marcos in the Sucre department of Colombia. METHODS: 144 rodents were captured in San Marcos' urban and rural areas using Sherman traps between December 2007 and July 2009. "Virus sin Nombre" (SNV)-specific antibodies were detected in plasma samples by an indirect ELISA immunoassay. RESULTS: An 8.3 % (12/144) seroprevalence rate was found. Specific seropositivity rates ranged from 6.8 % (3/44, Zygodontomysbrevicauda) to 50 % (1/2, Neacomysspinosus). No significant differences were found in seroprevalence according to capture area, gender and/or reproductive stage (p>0.05); however, there were more seropositive adult males. CONCLUSION: This is the first evidence of hanta virus seropositivity in rodents from the Murinae subfamily in Colombia. The presence of SNV antibodies in rodents in San Marcos supported the hypothesis that at least one hantavirusis circulating in rodents from northern Colombia.

Prevalence and risk factors for encephalomyocarditis virus infection in Peru.

Although encephalomyocarditis virus (EMCV) infection has been commonly documented among domestic animals, less is known about EMCV transmission among humans. Recently, we described the isolation of EMCV from two febrile patients in Peru. To further investigate EMCV transmission in Peru, we screened febrile patients reporting to health clinics in Peru for serological evidence of recent EMCV infection. We also conducted a serological survey for EMCV-neutralizing antibodies in the city of Iquitos, located in the Amazon basin department of Loreto, Peru. Additionally, we screened serum from rodents collected from 10 departments in Peru for evidence of EMCV exposure. EMCV infection was found to be only rarely associated with acute febrile disease in Peru, accounting for <1% of febrile episodes analyzed. Despite the low acute disease burden associated with the virus, human exposure was quite common, as prevalence of EMCV-neutralizing antibodies ranged between 6.0% in the coastal city of Tumbes and >17% in cities in the tropical rainforest of northeastern Peru (Iquitos and Yurimaguas). On the basis of the serological survey conducted in Iquitos, risk factors for past infection include increased age, socioeconomic indicators such as residence construction materials and neighborhood, and swine ownership. Evidence from the rodent survey indicates that EMCV exposure is common among Murinae subfamily rodents in Peru (9.4% EMCV IgG positive), but less common among Sigmodontinae rodents (1.0% positive). Further studies are necessary to more precisely delineate the mode of EMCV transmission to humans, other potential disease manifestations, and the economic impact of EMCV transmission among swine in Peru.

Postepizootic persistence of Venezuelan equine encephalitis virus, Venezuela.

Five years after the apparent end of the major 1995 Venezuelan equine encephalitis (VEE) epizootic/epidemic, focal outbreaks of equine encephalitis occurred in Carabobo and Barinas States of western Venezuela. Virus isolates from horses in each location were nearly identical in sequence to 1995 isolates, which suggests natural persistence of subtype IC VEE virus (VEEV) strains in a genetically stable mode. Serologic evidence indicated that additional outbreaks occurred in Barinas State in 2003. Field studies identified known Culex (Melanoconion) spp. vectors and reservoir hosts of enzootic VEEV but a dearth of typical epidemic vectors. Cattle serosurveys indicated the recent circulation of enzootic VEEV strains, and possibly of epizootic strains. Persistence of VEEV subtype IC strains and infection of horses at the end of the rainy season suggest the possibility of an alternative, cryptic transmission cycle involving survival through the dry season of infected vectors or persistently infected vertebrates.