“Tamil Nadu (the southern most state in the Indian peninsula) has always been the leader in immunization,” says Dr. T. Jacob John, virologist at the Christian Medical College, Vellore, Tamil Nadu. Though small pox was eradicated in India in 1974, Tamil Nadu had already accomplished this almost a decade earlier, in 1965.

In 1977, India accepted the World Health Organisation’s (WHO) Expanded Program on Immunization (EPI), except for the Measles vaccine. But, in 1978, Tamil Nadu introduced the Measles vaccine against national policy. By 1984, India’s Planning Commission finally acknowledged this as a “fantastic success” and by 1990 it was introduced all over the country, says Dr. John. Tamil Nadu also became the first state to conduct laboratory investigations of measles outbreaks. There are no more deaths to due measles in the state.

Dr. John attributes these strides in public health to the state’s former health minister Dr. H. V. Hande. In 1986, Hande ordered five doses of Oral Polio Vaccine (OPV) for infants. The national policy only granted three doses, so Hande got Rotary International to sponsor the additional doses. Tamil Nadu became the first state to eradicate Polio.

Sadly, this trend is in reverse. The second National Family Health Survey (NFHS-2) in 1998-99, recorded 89 per cent complete vaccine coverage of children between 12 and 23 months old. This has fallen to 81 per cent, according to the NFHS-3 in 2005-06.

Nowadays, only the first OPV dose is given free and peopled are forced to spend Rs. 500-600 on vaccines for infants, says Dr. Shanmugavelayutham, Professor of Social Work at Loyola College, Chennai. He adds that the poor spend up to 40 per cent of their income on medical expenses in states like Tamil Nadu, where health awareness is high.

After the deaths of four babies in Tiruvallur district, close to Chennai- the state capital, in April, last year, due to a mix up of the measles vaccine, the state government ordered that vaccines only be given in government primary health centers (PHCs) and hospitals.

There are only 1420 PHCs for the state’s population on 66.4 million spread over an area of more than 50,000 square miles. A fourth of the population manages with family incomes of less than a quarter dollar a day. 22.5 per cent of the population are officially categorized as poor. The national figure stands at 27.5%.

Before the Tiruvallur tragedy, health workers went to individual households and vaccinated infants. As a result of the government order, daily-wage earners, who cannot afford to take a day off to travel to a PHC, are not getting their children vaccinated. This has lead to the number of vaccine recipients decreasing by almost 50 per cent, says Dr. Shanmugavelayutham.

Immunity from communicable diseases can be achieved by vaccinating up to a critical threshold of 80 to 85 per cent of the population and hence it will take two to three years for the immunity to fall below the threshold and diseases like measles, diphtheria and polio to make a comeback. Diphtheria outbreaks have already been reported from Vellore and Tuticorin districts of the state.