Shangdong: Beijing Flu’s Cousin Is Coming : Health: The deadly new strain is becoming the dominant one. And medical experts expect it to sweep the U.S. this winter.

The harsh Beijing flu that swept the United States last season is sending a relative to visit this season. Unfortunately, these strains are among the deadlier forms of the disease.

Shangdong joined its Chinese cousin, Beijing, this summer in a world tour, as strains of type A flu hit South Africa, the United States, Panama, Chile and Australia, the national Centers for Disease Control and Prevention reported recently.

In China, the source of the strains, Shangdong was overtaking Beijing as the dominant strain.

Flu contributes to the deaths of about 20,000 people a year in the United States. The flu season lasts from November to April.

Among the samples of flu gathered by a worldwide surveillance center at the CDC from October, 1993, through August, 1994, 80% were type A and 20% were type B. Almost all of the type A samples were related to the Beijing strain, but a quarter were more closely related to Shangdong.

Those who escaped Shangdong this summer may still suffer during the flu season. Strains from Panama and Texas are expected to appear with their baggage of chills, fever, headaches, fatigue and muscle aches.

Nancy Arden, the CDC’s chief of influenza epidemiology, said the CDC could not predict which strain would dominate this flu season. Usually, dominating strains alternate between types A and B.

But this year, as Shangdong and Beijing continued their globe-trotting, flu experts were uncertain about how dominant the milder B-Panama flu would be. “We never know what to expect from flu,” Arden said.

Type B-Panama is considered a less deadly flu, particularly when compared with A-Beijing, a severe strain that was widespread last season.

Protection against A-Shangdong, A-Texas and B-Panama are contained in this year’s U.S. flu vaccine. The best time for flu shots is from mid-October through mid-November.

Arden expects that the Texas strain would cause little illness this season. The CDC will get a better picture on the flu season during October when all states are operating flu surveillance centers.

The CDC recommends that people at high risk for influenza be vaccinated, such as the elderly, people in nursing homes, children, people who have chronic diseases, health care workers and those in close contact with people at high risk.