Our discussion of influenza virus replication has so far brought us to the stage of viral RNA synthesis. Last time we discussed the formation of viral RNAs, an event which takes place in the cell nucleus. Now we’ll consider how these RNAs participate in the assembly of new infectious viral particles, as illustrated in the …
Although the new influenza H1N1 strain has been receiving a great deal of attention, apparently last season’s H1N1 and H3N2 strains continue to circulate, at least in the United States. FluView, the weekly surveillance report from the CDC, indicates that during weeks 17 and 18, seasonal influenza A (H1), A (H3), and B viruses are …
Co-circulation of three human influenza A subtypes Read More »
We have spent over a week discussing the effects of polymerase error rates on viruses. RNA viruses have the highest error rates in nature, a property that is believed to benefit the viral population. For example, selective pressure from the immune system or antiviral drugs may lead to changes that are beneficial for the population. …
Here are answers to questions sent to virology blog about the new strain of influenza H1N1 that continues to spread globally. Q: Are you aware of efforts to make the virus strain nomenclature more informative? Understanding what segments/genes are related historically and sequence wise to what is confusing using the ‘serological’ definitions like H1N1. What …
Influenza A/Mexico/2009 (H1N1) – Questions & Answers Read More »
The influenza H1N1 outbreak in Mexico has been analyzed to provide information on the pandemic potential of the new virus strain. The estimates offer some insight into the transmissibility and severity of the virus but must be tempered with the understanding that there are still uncertainties about all aspects of the outbreak. Influenza incidence is …
Influenza A/Mexico/2009 (H1N1) virulence and transmission Read More »
The genome sequence of an RNA virus population clusters around a consensus or average sequence, but each genome is different. A rare genome with a particular mutation may survive a selection event, and the mutation will then be found in all progeny genomes. The selection process is illustrated in this diagram: The diagram on the …
