10 H3N2v Cases In Huntingdon County Pennsylvania
August 17, 2012
The Pennsylvania Department of Health today reported four confirmed and six probable human cases of influenza due to a new strain of the flu known as H3N2v.
The Pennsylvania cases occurred among youth participants in the Huntingdon County Fair, Aug. 5-11. There are no reported hospitalizations. Although the investigation is ongoing, there is no evidence to date of the new flu strain spreading from person-to-person.
This is the same virus that has recently caused illness in Indiana and Ohio, mostly among children who were exhibitors at or attended agricultural fairs. The illnesses reported in Pennsylvania are also mostly in children and are typical for the flu.
The above comments from the Pennsylvania Department of Health report cite 10 likely H3N2v cases associated with the Huntingdon County Fair in central Pennsylvania. The 10 initial cases suggests the number will rise, and this large number of cases once again signals human to human transmission that is almost certainly not linked to swine.
The CDC released 10 more sets of sequences yesterday from cases in Ohio and Indiana. All were a novel sub-clade first identified at a day care center in West Virginia in late 2011, where there was no swine exposure. The 23 ILI contacts signaled efficient transmission, which has been seen at multiple sites, including the above fair.
This novel H3N2v has rarely been noted in swine and it has clearly adapted to humans. The most 20 recent H3N2v sequences, including 18 from 2012 have been the novel sub-clade from West Virginia.