SAN DIEGO (KGTV) — The H1N1 strain of influenza is the most prominent strain of the illness in San Diego and around the nation so far this flu season, according to local health officials.
Of 1,730 confirmed cases reported in San Diego this season, nearly 94 percent are influenza A, the County Health and Human Services Agency reported Wednesday. Influenza A covers H1N1 and H3N2. During the year, H3N2, or the "seasonal flu," is the primary virus in circulation.
This year, however, there are 10 cases of H1N1 for every case of H3N2, health officials said.
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The strain affects young to middle-aged adults more than other age groups. The Centers for Disease Control and Prevention believes this is because older adults have been exposed more to H1N1 and younger adults tend to have lower vaccination rates.
"Older people have some element of immunity to Pandemic H1N1 because they’ve had more exposure to these influenza viruses than younger groups," said Sayone Thihalolipavan, county deputy public health officer, said.
Last week, a 26-year-old woman visiting San Diego from Washington, D.C., died possibly due to H1N1 complications. She was also suffering from meningitis, though it's unclear if she had been vaccinated or suffered from any other underlying medical conditions.
Another local resident, identified as a 49-year-old male, died of the flu, according to health officials. That man did have underlying medical conditions though it wasn't clear if he had been vaccinated.
This season, there have been nine flu-related deaths, officials say, compared to 44 deaths at this time last season.
Health officials advise the best way to prevent the flu is to get vaccinated, wash hands thoroughly and often, avoid going out if you're sick, and clean commonly touched services. Those with underlying chronic conditions, pregnant women, people who live with or care for others who are high risk, and those 65 and older are most at risk of catching the flu.