SAN FRANCISCO (KPIX 5) — As the number of flu-related deaths increases in the Bay Area, the lines for flu shots are getting longer. Unfortunately, the high demand has put the vaccine in short supply at some places.

A few Bay Area Walgreens and CVS stores had to turn people away after they ran out. The retail chains said it’s only temporary and they will be restocked in a couple of days.

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The H1N1 strain of the virus, also known as swine flu is now widespread in California. State health officials said the number of flu-related deaths has killed 13 in the Bay Area and Santa Cruz County, so far.

“It’s important to get it (a flu shot) every season especially the vulnerable, young children, those who have asthma, and the elderly,” said Dr. Eleanor Chung.

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This year the virus is not discriminating. Younger people are getting hit hard like 23-year-old Matty Walker. The Sonoma County man died last week. He was healthy before he got sick, and had no preexisting conditions.

“Even among the healthy, the flu can be fatal,” said Chung.

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Doctors insist the best line of defense is the flu shot and it’s not too late to get one. Flu season usually peaks in January or February. If you haven’t had one, Walgreens suggests calling ahead to make sure it’s in stock.