CONCORD, N.H. — Public health authorities in New Hampshire say four people who have been identified with Legionnaire’s disease likely acquired the disease in Hampton.

The New Hampshire Department of Health and Human Services’ Division of Public Health Services says the four people likely acquired Legionella at the end of July or beginning of August in a localized area of Hampton. Legionnaire’s disease, also called Legionella pneumonia, is a bacterial pneumonia.

The public health department says it is investigating for additional cases of the disease, as well as for the source of the infections. The disease is usual spread by inhaling droplets of water contaminated with the bacteria.

Many people exposed to Legionella do not get sick. The disease has the ability to cause serious illness and death, however.