C1 TAKING THE SHOTS

time retain the image of the virus in their memory. Thus, we get protected from future attack from the actual measles virus without getting ill at all.

How effective are vaccines?

Vaccines are not 100 percent effective. The recommended two doses of the measles vaccine, for example, are only 97 percent effective at preventing measles. But still, if a vaccinated individual does develop the disease he/she was vaccinated against, the disease is likely to be less serious.

How safe are vaccines?

A vaccine is rigorously tested for safety and efficacy across multiple phases of trials before it is approved for use. Once it is in the market, it is subjected to post-marketing surveillance, which aims to assess its long term effects. This meticulous post-marketing surveillance is the reason Sanofi Pasteur, the manufacturer of Dengvaxia, found out that their vaccine was effective in preventing dengue only in

A vaccine contains material that resembles a disease-causing microorganism such as a weakened or dead microbe, its toxins, or one of its surface proteins that, when introduced into our body, will not make us sick (because the viruses are weakened).

children who have been previously naturally infected with the dengue virus and that in those who had no prior exposure to the virus it can give rise to a more severe form of the disease.

Those vaccines that have been in use for many years now, such as BCG, Oral Polio Vaccine (OPV), Diphtheria, Tetanus & Pertussis (DPT), Hepatitis B, and Haemophilus influenzae Type B, and Measles, Mumps & Rubella (MMR), have passed the post-marketing surveillance they have been subjected to and are certified safe.

Scientific studies—such as the one published in July 2014 issue of the Medical Journal of Pediatrics, which reviewed 20,000 scientific titles and 67 papers on vaccine safety—consistently show that side effects of vaccines outside of soreness and redness at the injection site are extremely rare.

Incidentally, the British study published in 1998 that linked autism to childhood vaccines, which caused quite a stir and is responsible for much of the vaccine hesitancy of parents in the western world, was actually retracted after it was exposed to be an elaborate fraud.

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