2 children in Boston infected with meningococcal disease

The spread of meningococcal disease happens through saliva and requires close contact, according to the public health commission.

Two young children in Boston were diagnosed with meningococcal disease, which is infectious and can lead to meningitis, a bacterial infection of the brain and spinal cord, officials announced Wednesday.

“Both cases have been associated with day care centers specializing in serving children who have experienced homelessness, however it is not currently known if the two cases are connected,’’ Mayor Martin J. Walsh and the Boston Public Health Commission said in a statement.

All of the people who are known to have been in close contact with the children have received antibiotics to reduce their risk of getting infected, officials said. The last day either of the children was at one of the day-care centers was Friday.