WEST TISBURY, Mass. — A newborn baby girl is receiving around the clock intensive care at Mass General Brigham after her parents said she was bitten by a tick on Martha’s Vineyard.
They said it happened on a bike path near their home in West Tisbury.
The family of one-month-old Lily Sisco believes she contracted Powassan virus, a rare but potentially fatal tick-borne disease that doesn’t have treatment.
She was flown to Boston after her symptoms progressed to seizures.
Martha’s Vineyard health officials are waiting for final test results to confirm the diagnosis.
“She is still fighting daily at MGH and continuing to leave the doctors speechless with her progress,” wrote her mother Tiffany Sisco in a Facebook post over the weekend. “Please, please, please check yourselves, your children and your pets.”
Lily began experiencing symptoms of a fever after her parents said they spotted a tick on her the size of a needle tip.
If the Powassan case is confirmed by health officials, it would be the second known case on Martha’s Vineyard in 20 years.
“This has been a particularly severe tick season in the northeast,” said Dr. Jacob Lemieux, Infectious Disease Physician at Mass General Brigham. “We also think we’re likely seeing the tip of the iceberg with Powassan virus.”
Dr. Lemieux, who’s not involved in Lily’s care, said many people who are exposed to Powassan may not know it.
“Many patients who are exposed to Powassan virus don’t become infected or become infected and develop mild symptoms,” said Dr. Lemieux.
Dr. Lemieux pointed out that reports show Powassan can be transmitted in as little as 15 minutes.
The CDC recorded 397 Powassan cases nationwide between 2004 and 2024 with 50 deaths.
There have been 24 cases nationwide so far this year, and three of those cases were recorded in Massachusetts.
Severe cases of Powassan can cause long-term neurological complications.
Health experts recommend people use 30 % DEET-based repellent on their skin and a permethrin-based repellent on their clothing to prevent tick bites.
A GoFundMe page to help pay for Lily’s medical expenses raised more than $25,000 as of Tuesday night.
This is a developing story. Check back for updates as more information becomes available.
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