Monthly Archives: April 2004

Smallpox Eradication


      Friends, Smallpox is the only major disease that has ever been eradicated. This disease has caused a huge amount of pain, disfigurement and death throughout human history.

In a typical year like 1967 small pox infected 10 to 15 million cases worldwide and killed 2 million of these. An estimated 300 million people died of small pox in the 20th century alone. In 1796 Jenner invented the small pox vaccine.

      However having a vaccine is a matter of science. And eradication of a disease is a matter of management and politics. The rich countries got people vaccinated but the disease was still widespread and caused 300 million deaths in 20th century. SOmething had to be done!

      In 1959 the World Health Organization passed a resolution to kill this disease. In 1967 the WHO launched the Intensified Small Pox eradication programme. At that time the strategy was to vaccinate everyone in the world- mass vaccination. But just imagine how difficult it is to ensure that 100% of the polulation is vaccinated.

      In 1966 an outbreak in Nigeria showed a better strategy.

In Nigeria 90% of the polulation was already vaccinated. But there was an outbreak of smallpox in a religious group who had resisted vaccination. The availibility of the vaccine was delayed to the local medical team forcing them to invent a new strategy. The local medical team isolated new cases and went looking for any new patient. They vaccinated people who were close to the existing cases and isolated these cases. So this strategy of surveillance and containment broke the small pox transmission chain even though less than 50% of the polulation needed to be vaccinated.

      This strategy of containment and surveillance was adopted by WHO for its worldwide campaign. Health teams moved across the world finding new cases and isolating them and vaccinating their contacts. Prize money was given to anyone who reported a small pox case.

      Another contributor to the success of this effort was the high volume production of vaccines. Before 1959 liquid small pox vaccine was used. It had to be used within 48 hours. This resulted in shortage of vaccine and contamination. A new freeze dried vaccine which had the stability for mass vaccination was invented and this was used in the campaign. Another invention – the bifurcated needle was needed for easily presenting single doses of the vaccine.

      However the greatest contribution to the campaign was by the local field workers. In each area the field workers invented techniques that could help them locate new cases. WHO only gave guidelines to the workers on how to go about their task. The workers had full freedom to create or modify strategies to suite the local population.

      In India Operation Smallpox Zero was launched in 1975. Village to Village searches were replaced by house to house searches. There was no chance taken. Even a case of simple rash where the chances of it being smallpox were low were treated as smallpox and the whole family was vaccinated. All villages within 10 mile radius of an infected case were searched. All people living within one mile radius of an infected case were vaccinated.  The number of infected villages fell by 40 % each month.

      Many people at WHO were unhappy with the way things were going.

They felt that the processes were not being followed. How could the local medical staff change the processes???!!! For example: obtaining money to fund vaccines, people and vehicles was a long affair requiring valuminous paperwork. Often this paperwork was not done by local staff and money flowed on “faith”. The local staff did not care about processes. There was only one aim: to eradicate smallpox!

      In 1977 the last case of smallpox was reported in SOmalia.

Small pox was completely defeated! The WHO director described this as “a triumph of management and not of medicine”.

But are we safe from this disease? This disease does not exist in people but the germs that cause this disease have been stored by several countries. The UN has requested destruction of all these germ samples. But countries like US, UK and Russia continue to keep huge stores of small pox germs. And the danger is that most of the children born after 1980 have not been vaccinated against small pox.

We have never been so vulnerable to this disease.


      Can another disease be wiped out like this? Yes! Polio is on its way out, just a matter of a few years. Polio and smallpox share a common feature- they do not have any animal reservoir. So diseases that are spread by animals or infect animals would be very difficult to eradicate. But who knows!



  Go, wondrous creature! mount where Science guides:                 

  Go, measure earth, weigh air, and state the tides:                 

  Instruct the planets in what orbs to run,                          

  Correct old time and regulate the Sun;