How well does flu vaccine work?
Two major reviews have come out in the past two months. Michiels et al from the University of Antwerp found that the vaccine does prevent influenza among those aged 6-65, "however, there is strikingly limited good-quality evidence of the effectiveness of influenza vaccine on complications such as pneumonia, hospitalization and influenza-specific and overall mortality..." as well as efficacy over 65. It is less the flu than the complications and deaths from flu that we want to avoid... but these complications are precisely what no one has been able to show are improved by vaccination. Vaccine 2011. Nov 15; (29) 49: 9159-70.
Michael Osterholm's group (U Minnesota) found effectiveness of standard (killed) flu vaccine for adults aged 18-59. His authors used as gold standard the presence of influenza virus by PCR or culture. No trials in adults over 65 or children below 18 met the strict criteria. For live flu vaccine, efficacy was shown for 9 of 12 seasons in 10 trials, but only for children aged 6 months to 7 years.
The group concluded, "Influenza vaccines can provide moderate protection against virologically confirmed influenza, but such protection is greatly reduced or absent in some seasons. Evidence for protection in adults aged 65 years or older is lacking. New vaccines with improved clinical efficacy and effectiveness are needed to further reduce influenza-related morbidity and mortality."
What to do?
Excerpted from: A Home Toolkit for Primary Prevention of Influenza by Individuals and Families. Finkelstein et al. DISASTER MEDICINE AND PUBLIC HEALTH PREPAREDNESS 2011; 5: 266-271. The authors of this review article are members of MIT’s Engineering Systems Division. They suggest the following proven methods:
• Wash your hands thoroughly after leaving a sick person’s room. Scrub with soap and water or an alcohol-based hand sanitizer for 20 to 30 seconds.
• Wear a mask. At minimum, the mask prevents a healthy person from transferring a virus to his/her own nose and mouth—the highway to infection.
• Install air filters. High-efficiency particulate air (HEPA) filters can remove nearly 98 percent of virus particles; portable air purifiers and pointing a window fan out the window of the sickroom can also help.
• Control temperature and humidity. Higher temperatures and humidity levels can kill or disable viruses.
• Install an ultraviolet light. UV light is antimicrobial, and portable air purifiers with both UV lamps and HEPA filters can be purchased for $180 to $370.
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