Maryland - Flu Strains in Circulation

[JimO]

http://dhmh.maryland.gov/fluwatch/

Maryland has had an interesting pattern over the past 6-8 weeks. Two postive samples of pH1N1, 8 H3N2, and 2 Influenza B were reported in Week 49. The proporation of pH1N1 increased through Week 1. Since then, although the number of positives have increased significantly, the relative proportions of each strain has remained similar. Maryland has reported Widespread activity for the past four weeks. However, %ILI and hospitalizations have not been unusual for a typical year.

I'm speculating that since pH1N1 arrived in Maryland early, most of it has likely been similar to the 2009 Pandemic strain for which the vaccine is effective. Perhaps that has kept the mutated UK variety from taking hold. It will be interesting to compare data from Maryland to states like PA, NC, and FL (sudden appearance and rapid increase of pH1N1 accompanied by deaths and/or increases in serious cases and hospitalizations). It would be interesting if Maryland ended up having a lower fatality rate from pH1N1 than other states over the coming weeks.

[Missouriwatcher]

Re: Maryland - Flu Strains in Circulation

Look at individual week's % (not season totals to date):

Week: 49....52.....1......2......3......4 (rounding)
A/H1: 0.0% 40% 46% 17% 51% 40% (percent of positives by PCR for week)
A/H3: 0.0% 60% 53% 83% 47% 59%
Inf B: 0.0% 0.0% 2% 0.0% 2% 1%

Now compare with season totals:

Week: 48......49.....52.....1......2......3.......4: (season totals to date w/rounding)
A/H1: 17% /17% /38%/ 42%/ 45%/ 49%/ 47%
A/H3: 67% /67% /54%/ 53%/ 49%/ 47%/ 50%
Inf B: 17% / 17% / 8% / 5% / 8% / 5% / 3%

Somewhere after week 49 and by week 52 A/H1N1 had increased and weekly increased (excluding week 2) up to week 3. Now in week 4 there appears to be a decline. A/H3 increased and appeared to peak in week 2. Influenza B has appeared to be declining since sometime after week 49.

http://www.marylandfluwatch.org/a/marylandfluwatch.org/www/weekly-report/2010-11-season-weekly-reports