Literatus: The BCG lesson-A A +A
Tuesday, February 19, 2013
ON JANUARY 2006, France became sole user of BCG vaccine Statens Serum Institut (SSI) for tuberculosis vaccination. Not long after, rapid increase in cases of adverse reactions (ADRs) came up; such as abscesses (in 73 percent of patients treated), around 30 percent had local reactions (lymphadenopathy of above one cm in size), while 20 patients developed suppurative lymphadenopathy.
Christelle Chol, leader of those who followed the patients for two years, found that the ADRs became consistent a year after their appearance or detection. They published their findings at the Pharmacoepidemiology and Drug Safety (Dec 5).
BCG vaccine—or Bacillus Calmette-Guerin (named after its discoverers)—contains weakened but alive strain of Mycobacterium bovis (a strain found in pigs). Because the bacteria can still stimulate reaction from a person’s immune system (without causing disease), it prepares the body to combat and destroy tuberculosis bacteria upon exposure. Studies in 1994 to 1995 showed a protective rate of 60 to 80 percent.
A clinical trial (1966) in the United States (Georgia and Alabama), however, showed only an efficacy of 14 percent. This figure left the authorities unconvinced in the use of BCG for mass vaccination there. Another trial (1979) in South India showed no efficacy at all.
And now we have these ADRs occurring in France. It might just be a case of contamination like what happened in 1930 (the first ever mass immunization using BCG also in France) where almost all of 240 infants immunized developed tuberculosis, resulting to 72 deaths. But this time, the French authorities believed that the ADRs came from the vaccine formulation itself.
The French problem is one of the many stories that highlight the dangers of synthetic medicines to health and life vis-à-vis their obvious accomplishments in chemotherapeutics. It tells of the imperfections of medical science and technology; an imperfection that can be deadlier than the disease it is designed to combat.
It does invite the patients to be well-informed in the dynamics of their own health problems. First, it helps them avoid aggravating conditions. Second, information today is just a Google away, so to say. Third, it gives you the power to decide on your treatment options.
Don’t forget that the limits of the scientific method do not remove the art in medical practice. Science functions within the limits of probability. And where probability is, there continue to exist an area of uncertainty. And in that area of uncertainty even experts can commit errors that have fatal consequences. In the end, all treatments must depend on your consent. That’s a basic right of the patient.
And here’s more: a well-informed patient can easily spot a well-informed healthcare professional.
Published in the Sun.Star Cebu newspaper on February 20, 2013.