2011 ARBOVIRUS SURVEILLANCE IN VERMONT

Alan C. Graham and Jon P. Turmel

Vermont Agency of Agriculture

103 South Main Street

Waterbury, VT 05671-0101

Alan.Graham@state.vt.us

Jon.Turmel@state.vt.us

ABSTRACT

The 2011 season in Vermont had more arbovirus activity than reports in the previous five years. WNV was detected in 3 mosquito pools and 16 dead birds, representing 12 crows, 2 raptors, and 2 passerine birds. Two human cases of WNV were reported. The first on 8/1 was detected in a routine Red Cross blood screening, while the second was more serious, involving a neuroinvasive case on 8/5. The first WNV report was from a positive mosquito pool of Culiseta melanura collected on 7/18 and the last was a crow found on 9/26. A dead emu from a farm with over 100 birds tested positive for EEE on 9/21. Eighteen additional birds died at this farm and two birds with neurological issues recovered. This was the first reported case of EEE in Vermont. Extensive trapping around the site found no active virus activity in the mosquitoes tested. A fall survey of moose and deer serum in 2010 (507 animals) found that 10.8% of the deer (n = 493) and 28.6% of the moose (n = 21) tested positive for EEE antibodies. All three bear samples tested negative for EEE antibodies. Deer serum from the southern part of Vermont was tested for tick borne disease antibodies. Out of 98 samples analyzed, 73.4% tested positive for Lyme disease and 36.7% tested positive for Anaplasmosis.