Healthy people not immune from H1N1 swine flu
By David Liu davidl at foodconsumer dot org and edited by Sheilah Downey sheilahd at foodconsumer dot org
Tuesday oct 13, 2009 (foodconsumer.org) -- Healthy people are not immune from H1N1 swine flu although the majority of people hospitalized with the illness have chronic medical conditions, a U.S. top health official said Tuesday.
Of those who were hospitalized, more than half of the adults had conditions such as asthma, chronic lung disease, heart disease or immune system disorders, said Dr. Anne Schuchat, director of the Centers for Disease Control and Prevention's National Center for Immunization and Respiratory Diseases, at a press conference held this afternoon.
Of adults hospitalized with the H1N1 (swine) flu, 45 percent did not have any known preexisting medical conditions and six percent were pregnant women, Schuchat said.
As for children hospitalized with H1N1 flu, it is unknown what percentage of them had underlying health conditions. But an early report from the CDC said two-thirds of the children who died from H1N1 flu complications had preexisting medical conditions. This time, Dr. Schuchat was cited by the media as saying that about 30 percent of the children who died had chronic medical conditions.
The early report cited health conditions like neurodevelopmental disorders as the majority of underlying conditions. But today, Schuchat mentioned asthma, cerebral palsy and muscular dystrophy. Severe bacterial pneumonia was also found in 30 percent of the children who died.
"The most common underlying conditions [for children] were asthma and chronic lung disease, neuromuscular diseases and sickle cell or other blood disorders," Schuchat was quoted as saying.
The findings came from records of 1,400 hospitalized adults and more than 500 hospitalized children whose medical centers participate in the CDC's Emerging Infections Program Network.
As of last Friday, H1N1 flu was implicated in 12,384 hospitalizations and 1,544 deaths of which 81 are pediatric with five reported last week.
Schuchat said nearly 10 million doses of the H1N1 vaccine are available and the first shipments will be the nasal spray type called FluMist, a live-virus based vaccine, which is only recommended for healthy people. It is not recommended for pregnant women, who are at higher risk of H1N1 flu complications.
The efficacy of four vaccines to fight the H1N1 virus, approved recently by the Food and Drug Administration, remain largely unknown. Health officials at the CDC said early that the H1N1 flu vaccine triggers robust immune response in 76 percent of the children older than 9 years receiving the vaccine, 36 percent in children ages 3 to 9 years and 25 percent in children between 6 months and 36 months.
The vaccines have been tested in trials of a couple of thousand healthy subjects although the H1N1 virus is much more risky to children with medical conditions. The real efficacy of the vaccine in high-risk children remains unknown.