(Newser) – Laurie Sylvia started feeling sick last Monday. Less than a week later, the Massachusetts 59-year-old was dead, killed by a rare mosquito-borne illness. Sylvia, who died Sunday, is the fourth person in the state to contract eastern equine encephalitis (EEE) this month. That's notable considering an average of just seven people typically contract the virus per year in the entire country, People reports. Before this year, Massachusetts hadn't seen a human case since 2013. Cases typically occur in Massachusetts, Florida, New York, and North Carolina. All four of the August cases occurred in Bristol County, though Sylvia was a realtor who did business in several counties, so her husband isn't certain where she contracted it.

The virus, which initially causes chills, fever, a stiff neck, headache, lethargy, and joint pain, was found in 330 mosquito samples taken from across the state. Bristol and Plymouth counties have completed aerial spraying for mosquitoes while other counties in the state are set to do the same, NBC Boston reports. But officials are still urging residents—especially those in the 23 communities at critical risk for EEE, the 22 at high risk, and the 52 at moderate risk—to take personal precautions against mosquito bites. Recovery from the virus is possible if it doesn't reach the central nervous system, but it kills one-third of those who contract it and others can be left mentally or physically disabled. "I just don’t understand how such a beautiful person could be taken from me so soon," Sylvia's daughter wrote on Facebook. "I wasn’t done." (Girl, 2, dies after tick bite.)

