So the researchers are looking not only for the cause (virus, bacteria or toxin), but also for a carrier (rats, livestock or bats) and perhaps even for a vehicle (sand flies, drink or fruit).
Therefore, convection can only cause virus dissemination at early time points but becomes insignificant at late time points.
A number of studies suggested the possibilities that hormone imbalance may cause virus reactivation including HSV-1.
This could repeatedly cause virus population bottlenecks (small population size) which favor the amino acid substitutions by genetic drift over those by natural selection [ 57].
Moreover, the detection of bacterial pathogen can mask an underlying viral cause; virus isolation may not always be successful and alternative methods of detection like IFAT can lack sensitivity and specificity compared to molecular detection methods.
DI virus did not cause virus to become persistent or delay clearance, and the presence of high levels of HI antibody in DI-treated, A/Cal-infected animals suggest that ferrets would be able to resist a repeat dose of virus.
