Massachusetts state officials have urged horse owners in the state to vaccinate their horses against West Nile virus (WNV) and Eastern equine encephalitis (EEE) after a second horse was euthanized last week. This was the first case of EEE in Worchester County since 2003.

According to a press release from the Office of Energy and Environmental Affairs for the state of Massachusetts, 56 horses have been infected with WNV and 26 with EEE since 2001.

"We've seen an unusual mix of hot weather and rainfall this year, which has led to an increased risk of mosquito-borne diseases that threatens not only residents but also our domestic animal population across the state, and in particular Bristol and Plymouth Counties," said Department of Agricultural Resources (DAR) Commissioner Scott Soares. "While the most effective time to vaccinate animals is in May, any unaffected equine can still benefit from the protection of vaccination."

The state has scheduled aerial sparying of the insecticide suminthrin, which is a synthetic version of a chemical found in chrysanthemum flowers, for the southern part of the state, according to Boston.com. Meanwhile, the Massachusetts DAR has asked animal and farm owners to help reduce potential mosquito breeding sites by eliminating standing water often found in tires, wading pools, and buckets. Other farm management tips include regular cleaning of water troughs, stalling horses at night to reduce exposure to mosquitoes, and using fans in barn areas