Medicine is all about risks and benefits, and this comes into stark focus with the news that the vaccine designed to protect teenagers against meningitis can cause Guillain Barre Syndrome (GBS), a severe neurological disorder.
So far, 15 teenagers and two adults in America have developed GBS after being given Menactra, the vaccine that protects against meningococcal disease, a major cause of bacterial meningitis. Five cases were reported in October 2005 alone. Each person has recovered or is recovering.
America's drug regulator, the Food and Drug Administration (FDA), can't be sure about the extent of the problem, but estimates the vaccine is causing 1.25 cases of GBS for every million vaccinations.
On the other hand, one in 100,000 adolescents aged between 11 and 19 gets meningitis every year; of these, 10 per cent are fatal and 11 per cent may have permanent disabilities.
As we say, it's all about risks and benefits.
(Source: The Food and Drug Administration website).