ESSEX — State officials have raised the threat of the mosquito-borne illness Eastern equine encephalitis in the town of Essex from “moderate” to “critical,” skipping past “high.”
The change in threat level Tuesday came after an Essex horse was diagnosed with Eastern Equine Encephalitis (EEE) last week and confirmed late Monday by state officials. The “critical” threat level signifies that multiple cases of EEE in people could be extremely likely at the time, according to the state Department of Health.
The state sets an area’s risk level at “critical” when there has been at least one human or animal case of disease or rapid escalation of indications in the area during the year.
The Essex horse, boarding at a veterinarian’s stable in New Hampshire since growing ill, will likely recover from the mosquito-borne disease, according to Essex health board’s administrative assistant Ann White.
“It’s expected to survive, so that’s pretty amazing,” White said. “That’s very unusual.”
The Essex horse is the fifth horse in the state to suffer the illness, according to the state’s Department of Public Health. Since the disease is transferable only through mosquito bites, people and other animals cannot catch Eastern Equine Encephalitis from the infected horse.
However, cases of horse infections can act as an indicator for the possibility of human infection.
Approximately one third of humans who develop EEE die, according to a prepared statement from the Essex health board. Others may have mild to severe permanent neurological damage.
Initial symptoms of the illness typically include fever, alterations in level of consciousness, fatigue, confusion, seizures and sometimes a headache and stiff neck.
Seven humans have been diagnosed with EEE in Massachusetts, and, as of Thursday, 20 people had been diagnosed with West Nile Virus, another mosquito-borne illness, according to the state.