Respiratory viruses still active in Southern California

Our local data looks very similar to the nation wide data collected by the CDC (see graph)

Although we are certainly seeing a downward trend in the number and percent positives for both RSV and Influenza, we are still seeing endemic levels of RSV (defined as >10% of samples tested). Past history shows that once there are signs of drop off (as we have seen over the past 2-3 weeks) the trend accelerates and we will most likely be out of RSV season in the next 4 weeks. As for influenza A and B, we are continuing to see both still circulating in the community, although at much lower levels than 1 month ago. Interestingly, this year proved to be a big "B" year, much in part due the mismatch of not only A virus but of B as well. In light of these new strains, all three virus strain s in the influenza vaccine for the next year (2008-9 season) will differ from this year's vaccine. The choices for NEXT year's vaccine will be A/Brisbane/59/2007-like H1N1; A/Brisbane/10/2007-like H3N2and a B/Florida/4/20006-like virus.