Vaccines: part of the health care solution
Aspen, CO Colorado
Recently there have been letters questioning the efficacy of the influenza vaccine, as well as the method for determining the composition of each year’s immunization. It seems some factual information rather than conjecture would be appropriate.
Statistics document that seasonal influenza (flu) is a bad actor. Thirty-six thousand people die each year from flu in the United States; mostly the very young and those over the age of 65. It also takes its toll on those with chronic illnesses. Over 200,000 people are hospitalized each year and in addition over 100,000 develop ACS (Acute Coronary Syndrome) and stroke after suffering a bout with the flu. (This has to do with the immune response, which I will address subsequently).
Part of the problem with the flu vaccine in the U.S. is that only 40 percent of the population choose immunization. Even at Aspen Valley Hospital where staff must sign a declination statement if they refuse the influenza vaccine, the immunization rate is only 60 percent. How can we get the protection from “HERD IMMUNITY” if the herd is not immune? Admittedly the vaccine is not perfect and even on a 100 percent match year, protection is only 70 percent to 90 percent depending on individual factors (general health and immune response). But many vaccines provide some protection and lessen the illness duration and severity even if not matched perfectly.
The composition of each year’s flu vaccine is determined by the CDC (Center For Disease Control), the WHO (World Health Organization), and ACIP (Advisory Committee For Immunization Practices). The CDC collects data from 120 cities and bases its selection on information received. It is evident the selection process is complex and complete. The vaccine usually has three inactivated viruses. Two of the viruses are influenza A and one is usually influenza B. This year’s (H1N1) A virus, Solomon Island Strain, prevalent from October through December, was covered by the vaccine 96 percent of the time. The second Influenza A virus (H3N2) was Wisconsin Strain. Unfortunately, this virus underwent ANTIGENIC DRIFT and became Brisbane Strain. Obviously our vaccine provided little immunity but did lessen the severity of illness. This virus began in January and presently is nearing its peak. Since it takes at least six months to produce new vaccine, the vaccine for the northern hemisphere couldn’t be modified. Fortunately, the vaccine for the southern hemisphere will include Brisbane, as their flu season is just beginning. The B virus also changed and is now Yamagata Strain which only appears about 20 percent as frequently as the A virus. The H and N designations refer to hemagglutins, which the virus uses for human cell destruction and neuramidases, which it uses to reproduce. Even viruses “need to get a life.”
Good health, proper nutrition, weight maintenance and moderate exercise are essential for a healthy life. In spite of doing all of the right things our immune systems sometimes are overwhelmed by various microbes. Anyone who has raised children remembers during the first few years of life they receive many immunizations. Where would we be without DPT, Polio, HPV, MMR, Hepatitis and Meningitis vaccines, just to name a few?
Our immune response is a double-edged sword. Limited immune response to a specific antigen provided by vaccines is helpful in preventing disease. Generalized immune response can be detrimental and can invoke a systemic response.
In prehistoric times a generalized immune response was a life and death situation following a traumatic event. Increased inflammatory response, clotting and vasospasm were essential for survival. In modern man the development of SIRS (Systemic Inflammatory Response Syndrome) can be detrimental in middle-aged people who might have soft lipid plaque and poor endothelial function (protective cells that line the inner layer of vessels). Many times the inflammatory mediators can cause these plaques to rupture and precipitate ACS, Acute Stroke, as well as various shock syndromes.
The U.S. has one of the best quality health care systems. The problems arise because of the high cost and limited accessibility of health care to many. Immunizations are cost effective, available and efficacious and we should embrace and not devalue them.
The best medicine for flu avoidance is frequent hand washing, covering coughs and yearly influenza immunizations. Continue to enjoy life, exercise regularly and attend to all risk factors proactively.