Measles — rare in the United States, although recently increasing in frequency — can be highly contagious, prompting an aggressive public outreach effort when a case is reported. The virus spreads quickly if an infected person coughs or sneezes or has close contact with someone who has not been immunized.
About 6,000 people visited the aquarium over the course of those two days, and any of them could have contracted the virus if they passed through the main building in the afternoon and were not immunized.
“It’s a unique event,’’ said Tony LaCasse, the aquarium’s spokesman, noting that staff cannot recall anything like this happening before.
Yesterday morning, the aquarium responded by posting information on its website, conducting interviews with the media, and calling and e-mailing many visitors.
The aquarium had the capacity to provide some kind of direct communication to about a third of the visitors because they arrived as part of tour groups or school field trips, including a few hundred from Quebec, LaCasse said. In those cases, the aquarium notified group leaders, who then spread word among the other participants of the group.
The volunteer has not been publicly identified. LaCasse said he has worked at the aquarium for a couple of months, commuting from Vermont. “He is very dedicated,’’ LaCasse said.
So far, the aquarium and city health officials are not aware of anyone being infected by the volunteer.
Symptoms usually begin 10 to 12 days after exposure and include a fever, cough, runny nose, red watery eyes, and a sore throat. A few days later the telltale rash appears, usually first on the face.
Anyone who thinks they were exposed should check their immunization records.
A person can be at risk of contracting measles without direct contact with an infected person. The virus can linger at a location about two hours after an infected person has left, and 90 percent of those exposed will contract the virus, Anita Barry, director of the infectious disease bureau at the Boston Public Health Commission, said in an interview yesterday.
“It is very contagious,’’ Barry said.
