A crowd of onlookers in downtown Providence may have been exposed to rabies last month by a bat that a man was carrying in a box, health officials said on Thursday.

The warning came after two individuals who said they were in a downtown plaza on January 23 were treated for possible rabies exposure, said Peter Hanney, spokesman for the Rhode Island Department of Health.

Officials believe the cause may have been a bat that a man was carrying in a box and displaying to onlookers. One of the individuals had a bat bite, and the other had handled the box, Hanney said.

It remains unclear if the bat had rabies or not, since it eventually got away, Hanney said.

Health officials urged both the unidentified man - described as mid 50s, about six feet tall with a beard and glasses - and anyone who may have been in the downtown Kennedy Plaza on the morning of January 23 be evaluated for possible exposure.

Rabies is very rare these days, said Hanney, adding the last case of human rabies in Rhode Island was in 1940.

Bat rabies, however, is highly transmissible to humans, even without a bite or scratch from the animal, the health department said. If treatment begins soon after exposure, it is fully preventable, it added.

Hanney said early symptoms, which many not appear for weeks or even months after exposure, include fever, confusion and dizziness.

In neighboring Massachusetts, a man recently died after being critically ill for about a month with the state's first reported case of human rabies since 1935. In December, a middle-aged woman in South Carolina died after contracting that state's first case of human rabies in half a century.

One to three human rabies cases are reported in the United States each year, mostly due to exposure to rabid bats. About 55,000 people die of rabies every year in other parts of the world, largely due to exposure to rabid dogs, officials say.