County, state and federal public health officials are urging people to get a flu shot if they haven’t done so already, to protect against a form of the H1N1 virus that caused a worldwide pandemic in 2009.
The H1N1 outbreak in 2009 killed at least 553 Californians, including three people in San Luis Obispo County, according to state records.
“If you have gotten a flu shot, good. If you haven’t, get one,” advised Dr. Jim Beebe, lab director for the County of San Luis Obispo Public Health Laboratory.
The strain of virus known as influenza A pH1N1 is the predominant strain circulating this year nationwide, health officials said. The strain is a slight variation on the 2009 H1N1 virus and can cause severe illness to people of all ages, but is unusual in that it hits children and healthy young adults harder, health officials said.
So far, flu cases in California have been localized, rather than widespread, according to data collected by the state up to Dec. 14.
In San Luis Obispo County, 49 of the 50 flu samples tested so far have been influenza A pH1N1, Beebe said. The county lab has been soliciting samples from local urgent care centers, clinics and hospitals.
“We only have two reports of hospitalizations as of this afternoon,” Beebe said Tuesday. “School absenteeism is not at a serious level yet. But the transmission season is only beginning.”
The flu season generally runs from November through April, health officials said. Flu smptoms include fever or chills, cough, sore throat, congestion, body aches, headaches, fatigue and sometimes vomiting or diarrhea. Anyone who feels ill should stay home, and help those around them to stay healthy by washing hands frequently and covering coughs or sneezes, Beebe said.
“If you think you’re ill, you need to stay home and take care of yourself,” Beebe said. “This is a very serious illness.”
On Tuesday, the federal Centers for Disease Control and Prevention issued an advisory to physicians alerting them to "severe respiratory illness among young and middle-aged adults, many infected with influenza A pH1N1 virus. Multiple hospitalizations, including many requiring intensive care unit admission, and some fatalities have been reported."
Among 1,071 known influenza cases between Oct. 1 and Dec. 21, the CDC reported, 92.6 percent were influenza A, and 97.7 percent of those were subcategory 2009 pH1N1.
"If pH1N1 virus continues to circulate widely," the CDC warned, "illness that disproportionately affects young and middle-aged adults may occur."
The CDC recommends annual vaccinations for people six months and older. People who show symptoms of the flu should consider seeing a doctor for anti-viral medicine, the CDC said.
"If not enough people get vaccinated in a community, there is always an increased risk for influenza to reach epidemic proportions and for localized outbreaks to take place," said Dr. Gilberto Chavez, California state epidemiologist.
This year’s vaccine covers the A pH1N1 strain but takes about two weeks to offer full protection and lasts about three months. Since that protection may not last through the flu season, many doctors advise the elderly, in particular, to get two doses of the vaccine, three months apart.
Cynthia H. Craft of The Sacramento Bee contributed to this story.