NEW BEDFORD, Mass. — The annual peak for flu season is still ahead, but already Southcoast Health doctors are seeing a pickup in the number of cases they have treated.

Dr. Robert Caldas, Southcoast Health Chief Medical Officer, said that St. Luke’s, Charlton Memorial and Tobey hospitals have diagnosed more than 40 cases so far, but the peak of flu season has yet to arrive.

“We’re just starting to see an uptick,” he said. The flu season usually peaks in January and February.

“We’re seeing vastly more cases of Type A strains [of flu virus],” Caldas said. Type A strains mutate readily, which makes them difficult to vaccinate against.

“They undergo genetic drift,” he said. “The virus has the ability to transform itself during the season. That’s why the vaccines are never 100 percent matched.”

While there have been reports that the current vaccine is only 10 percent effective, the Centers for Disease Control said that is an Australian interim estimate of the vaccine’s benefit against one flu virus, the H3N2 virus.

In the United States last season, overall vaccine effectiveness against all circulating flu viruses was 39 percent. Depending on how well matched the vaccine is to the virus, the CDC reports that vaccination can reduce the risk of flu illness by between 40 percent and 60 percent among the overall population.

Sometimes, more cases of Type B flu viruses will emerge later in the season, Caldas said.

Each year, the makers of the flu vaccine try to match the vaccine against what they know have been active strains of the flu. They distribute tens of millions of doses around the country.

Caldas said he believes Southcoast Health’s hospitals and Urgent Care centers are “fully supplied for the season.”

Caldas said the vaccine is safe for anyone over six months of age, including pregnant women. Seniors can get a special vaccine designed for people 65 and older. It includes nearly a double dose of the vaccine.

“You try to stimulate an adequate level of immunity with an aging population because age weakens the immune system,” and the larger dose is intended to stimulate an immune system response in the elderly, Caldas said.

The only people who should not be vaccinated are those who have had a documented reaction to the vaccine, or who have an allergy to eggs or who have had Guillain-Barré Syndrome, an autoimmune system disorder.

For the rest of us, getting vaccinated is the best defense against a disease that kills, on average, 36,000 Americans each year, according to the Centers for Disease Control.

“Vaccination does save lives, reducing cases and deaths by the millions each year,” Caldas said.

Flu vaccine is available at Southcoast Health Urgent Care centers in Dartmouth, Fairhaven, Wareham and Seekonk, or ask your physician.

If you already have the flu or want to avoid it, there is lots you can do to keep it from spreading.

• Frequent hand washing is still the primary way to keep yourself healthy.
• Cough or sneeze into your elbow or a tissue. If you use a tissue, dispose of it quickly and properly.
• Remember that the flu virus can live up to eight hours on hard surfaces. Disinfect door knobs, food preparation areas, washrooms and other areas.
• If you are sick, stay home. Get plenty of rest, drink lots of fluids and avoid tactile contact with uninfected family or friends. People with flu can spread it to others up to about 6 feet away, the Centers for Disease Control reports.