March 28 (Reuters) - The U.S. Centers for Disease

Control and Prevention issued an advisory on Thursday alerting

healthcare providers about an increase in invasive meningococcal

disease and urging them to ensure necessary vaccinations against

the deadly disease.

Meningococcal disease, caused by the bacterium Neisseria

meningitidis, is a serious bacterial infection that commonly

affects the brain, spinal cord and bloodstream.

As of Monday, 143 cases had been reported, compared with 81

cases this time last year, the CDC said. There were 422 cases

recorded last year, the highest annual number since 2014.

The increase in infections is mainly attributable to a

particular bacterial strain in the meningococcal bacteria group

Y.

An infection with this strain had disproportionately

affected people aged 30-60 years, African American people, and

people with HIV, the agency said, urging healthcare providers to

have a "heightened suspicion" for meningococcal disease among

these populations.

The agency also warned that patients may present with

bloodstream or joint infection and without symptoms typical of

meningitis, which include fever, headache, and stiff neck.

Four of the six meningococcal bacteria groups - A, B, C, W,

X, and Y - circulate in the United States, according to the CDC,

with vaccines available against all except the X group.

In October, the U.S. Food and Drug Administration approved

Pfizer's ( PFE ) vaccine Penbraya, the first shot to protect

against five meningococcal bacteria groups.

Pfizer ( PFE ) currently sells two vaccines to protect against

the disease, with Trumenba targeting the B group and Nimenrix

protecting against the other four bacteria groups.