Supplies of influenza vaccine are still available to B.C. residents, despite high demand as the H1N1 strain of the virus has returned, provincial health officials say.

Cases since the current flu season began in December have shown a shift towards people aged 20 to 69, rather than the very young and the elderly who are typically most vulnerable. There have been severe cases involving healthy, younger people and two deaths have been confirmed, one in the Okanagan and one on Vancouver Island.

The main strain of influenza to emerge this winter is a descendent of the H1N1 that prompted the largest vaccination in Canadian history in 2009-10, when the illness was declared a global pandemic.

Provincial health officer Dr. Perry Kendall said the B.C. health ministry purchased a record 1.4 million doses of the current vaccine, which offers immunity to H1N1 and other strains. Some doctors' offices and pharmacies have run out as demand has been higher than last year.

"We have supplies currently available, but it's conceivable that if demand continues to be high, we'll use up all of those 1.4 million doses," Kendall said Wednesday. "So I wouldn't call it a vaccine shortage, I'd call it an unusually high demand."

The health ministry has a website for information on influenza and other vaccinations, with a guide to finding local flu clinics, .

Since 2009, pharmacies as well as doctors' offices and dedicated flu clinics have been authorized to administer flu shots. They are free of charge to higher risk groups, including pregnant women, very young or old people, people with other medical conditions and those planning to visit a hospital or long-term care facility.

Flu season typically runs from December to April. Kendall said in an average year, between 10 and 20 per cent of B.C. residents contract the virus, with about 2,000 sick enough to be hospitalized and 500 deaths, mostly people with underlying conditions.

While severe illness among younger, healthier people is unusual, so far the current flu season is in the typical range, Kendall said.

Seasonal influenza is mainly a respiratory illness, with symptoms of coughing, fever, headache and muscle ache that typically last from seven to 10 days. It can be complicated by pneumonia and worsen underlying conditions such as heart disease.

Kendall said confirmation of "bird flu" is not a cause for public concern, because that strain is typically caught from poultry and rarely transmitted from person to person. A traveller returning from China to Edmonton via Vancouver during the Christmas season became ill and died Jan. 3.