This is a joint post with Rachel Silverman
Yesterday the global health community celebrated a much anticipated anniversary: one year has passed since India’s last reported case of polio. While still tenuous, this achievement is an important milestone for the international effort to attain polio eradication. If India can maintain this progress, then only three countries – Afghanistan, Nigeria, and Pakistan – will remain polio-endemic, down from 125+ countries worldwide in 1988. (As an aside, the WHO describes India as “one of the largest donors to polio eradication being largely self financed.” Are donations to oneself – or “unilateral” donors, if you will – the way of the future?)
While we applaud India for its commitment to reaching this milestone, let us not allow this recent success obscure the sorry state of vaccination in India. In 1985 the Indian government launched its Universal Immunization Programme (UIP), an effort to protect infants from six serious diseases including diphtheria, measles, pertussis, and polio. The chart below shows vaccination coverage from 1980 to 2010 based on DHS and UNICEF data. Vaccination coverage rose rapidly between 1985 and 1990. Unfortunately progress stopped around 1990, and coverage rates remain essentially unchanged since then. Over a quarter of all Indian children still do not receive basic immunization against diphtheria, measles, and pertussis, leaving them vulnerable to potentially deadly but preventable diseases. Household surveys from DHS paint an even more dismal picture – just 34% of Indian children under age 5 are fully immunized.
Figure 1. Vaccination coverage in India, 1980-2008 Source: UNICEF and DHS
India’s lack of universal vaccination has had predictable consequences. The first years of UIP coincided with a steep drop in the prevalence of corresponding diseases. Since about 1995, however, the reported cases of measles and pertussis have stagnated, even as polio cases approached zero.
Figure 2. Reported Cases of Diptheria, Measles, Polio and Pertussis: India 1980-2010 Source: WHO
We wonder whether India’s focus on polio may have come at the expense of other diseases such as diphtheria. Until 2000 polio and diphtheria followed roughly similar trends. Since 2000, however, diphtheria rates have been consistently higher. While India should be applauded for its contribution to global eradication, we urge India to consider the trade-offs in focusing on any one disease at the expense of another and, as much as possible, to try to piggy-back one effort to another. And most importantly -- India, please don’t slack now on both polio and immunization. The game is not yet over!
Figure 3. Diphtheria and polio cases in India, 1980-2000 Source: WHO