Lab testing identified the same strain of influenza in two of the three victims who died with respiratory sickness last week in Calvert County.
The county's health department has been investigating a cluster of illnesses that led to three deaths in Lusby, MD, near the Calvert Cliffs nuclear facility.
The Maryland Department of Health and Mental Health said on Wednesday afternoon that Influenza H3, a strain of Influenza A that has been circulating this season, was found in two of the cases.
The department said in both cases, bacterial co-infections, a known complication of flu infection, also contributed to the victims' deaths.
An 81-year-old woman was the first to fall sick, in late February. The woman's three adult children, two daughters and a son, traveled to her home to care for her. Subsequently, they became sick as well with similar symptoms. The mother and two of her children died in the first week of March.
On Monday afternoon, a team wearing hazardous material suits from the Maryland Department of Health and Mental Hygiene entered the home of the 81-year-old to collect samples. The Maryland Health Department, Maryland Emergency Management, and the Calvert County Health Department say they are continuing a coordinated investigation.
Currently, Maryland public health officials say there are no other clusters of severe respiratory illnesses like this case elsewhere in the state. The flu season is expected to stretch into late May.
