Flu season has yet to arrive in Whatcom County or most of the rest of North America, according to health officials, but when it comes, it could pack a punch.

The variety of flu going around the world this year is usually more severe and could kill more people, according to health agencies.

The World Health Organization reports that a large majority of the influenza viruses sampled so far have been the H3N2 strain, which is more severe than H1N1 - the dominant strain during the winter of 2009-10 and the first part of the 2010-11 flu season.

Annual death totals from H3N2 are, on average, 2.7 times higher than during H1N1 seasons, the Centers for Disease Control and Prevention said in a 2010 report.

For now, the number of flu cases in the United States is far below a typical seasonal peak, according to the WHO, which gives regular flu updates at its website, who.int/influenza/en.

That's bound to change The most common peak for flu season in Washington state is February. The second most common peak month is January, according to the state Department of Health.

Flu activity in Whatcom County has just begun to increase, according to a weekly flu report posted on the county's website at whatcomcounty.us/health/flu/index.jsp.

Four people in the county tested positive for influenza during the week of Jan. 1-7, but there were no flu-related hospitalizations or deaths in the county that week, the report said.

Last flu season, there were 36 reported flu deaths in Washington, according to the state Department of Health. All but seven of the victims were 50 or older.

The severity of flu seasons varies greatly. The number of people who have died from influenza annually in the United States has ranged from 3,000 to 49,000 over the past 31 years, the CDC reports.

The bottom line, said county health official Greg Stern, is that it's not too late to get a flu shot.

"Although seasonal H3N2 can cause severe disease in more people than H1N1, both can cause severe disease, and the vaccine offers protection against both," Stern wrote.

It's too early to gauge the vaccine's effectiveness, the CDC said. What the agency has found so far appears promising; almost all of the flu viruses in a small sample collected since Oct. 1 match the strains included in the vaccine.

The CDC recommends everyone 6 months of age and older get the vaccine.

A list of Whatcom County locations that offer flu shots, usually for a fee, is available at this county Health Department webpage (PDF).

FIGHT THE FLU

Public health officials say people can protect themselves against influenza, and prevent its spread, by taking these precautions:

• Use a tissue to cover your mouth and nose when coughing or sneezing. Then throw the tissue in the trash.

• Wash your hands frequently with soap and warm water, or use hand sanitizer.

• Keep your hands away from your eyes, nose and mouth.

• Avoid contact with people who are ill.

• Stay home if you are sick, and limit your contact with other people.