Spatiotemporal dynamics of Puumala hantavirus associated with its rodent host, Myodes glareolus.

Many viruses significantly impact human and animal health. Understanding the population dynamics of these viruses and their hosts can provide important insights for epidemiology and virus evolution. Puumala virus (PUUV) is a European hantavirus that may cause regional outbreaks of hemorrhagic fever with renal syndrome in humans. Here, we analyzed the spatiotemporal dynamics of PUUV circulating in local populations of its rodent reservoir host, the bank vole (Myodes glareolus) during eight years. Phylogenetic and population genetic analyses of all three genome segments of PUUV showed strong geographical structuring at a very local scale. There was a high temporal turnover of virus strains in the local bank vole populations, but several virus strains persisted through multiple years. Phylodynamic analyses showed no significant changes in the local effective population sizes of PUUV, although vole numbers and virus prevalence fluctuated widely. Microsatellite data demonstrated also a temporally persisting subdivision between local vole populations, but these groups did not correspond to the subdivision in the virus strains. We conclude that restricted transmission between vole populations and genetic drift play important roles in shaping the genetic structure and temporal dynamics of PUUV in its natural host which has several implications for zoonotic risks of the human population.

Detection of camel pox and vaccinia viruses by polymerase chain reaction.

PCR following two methods of DNA extraction was used to confirm the growth of camel pox virus (CPV) and vaccinia virus in cell culture and chorioallantoic membrane. Results were compared with the commonly used neutralization test. The first method of DNA extraction was accomplished by using viral DNA in tissue culture supernatant and Chorioallantoic membrane, which was released by initial heating for 15 min at 99 degrees C followed by ordinary PCR. In the second method DNA was extracted by using DNA Isolation Kit from tissue culture supernatant and used as a template. Rapid identification and differentiation of CPV and Vaccinia virus were achieved by PCR and this assay proved to be fast and feasible, and can be an alternative to orthodox serological methods.

Growth characteristic of Camel pox and Vaccinia viruses in embryonated eggs and cell culture.

Camel pox viruses isolated in Sudan and VD45 (African camel pox strain) and Vaccinia virus (Elstree strain) were used for inoculation of chorioallantoic membrane (CAM) of embryonated eggs (EE) and cell culture (CC). In EE Lesions were seen as pocks ranging in size from 1 to 1.5 mm in diameter, and they increase in size with serial passage and taking opaque- white and opaque- yellow colors. When propagated in Vero cells, these viruses gave clear CPE, characterized by rounding of cells, plaque formation, syncytia and detachment of cells from the glass.