The recent correspondence on pneumococcal vaccine(1-3) prompts the following considerations:

Undoubtedly, there is paucity of data to suggest that pneumococcal disease is a significant problem in India; this argues against considering vaccination(1,2). But "absence of evidence’ cannot be interpreted as ‘evidence of absence’ of pneumococcal disease. Therefore, pending the availability of good quality data, it may be prudent to analyze whether there is any reason to believe that the disease burden is likely to be lower than observed in limited studies and other developing countries. If not, this indirectly suggests a relatively high burden that argues in favour of vaccination. It may be recalled that paucity of large community based studies on epidemiology of Hib disease has been partly responsible for not incorporating Hib vaccine into the national schedule.

The polysaccharide vaccine can be used only in older infants and hence does not offer adequate protection since the disease also affects young infants. The serotypes in the 7-valent conjugate vaccine being aggressively marketed account for only half of those responsible for invasive disease among children under five years of age based on current data(4,5). Therefore, both are not worth considering for universal vaccination on epidemiological grounds, irrespective of economic considerations. The efficacy of the polyvalent preparations currently undergoing multicentric trials remains to be determined.

A large multi-centric, community based epidemiological study to confirm the high burden (or otherwise) of pneumococcal disease and the serotypes responsible.

Professionals need to send a clear message to policy makers about the need (or otherwise) of vaccines for universal immunization. This must be done based on epidemiological considerations in the context of our country, safety profile and efficacy. Policy makers need to consider economic factors in addition to these. Taking up this responsibility on their behalf will only provide an excuse for policy makers to defer/cancel decisions in favour of introducing vaccines. Perhaps this is why no new vaccine has been incorporated in the national schedule after 1985 (measles vaccine) despite great strides in economic and technological spheres. On the other hand, it should be remembered that unprecedented amounts of money have been (and are being) spent on supplementary vaccination with OPV. Therefore, where there is a will (to vaccinate), there will be a way (to pay), pun intended.

Manufacturers should be "encouraged" to design a Pneumococcal vaccine that is efficacious in the context of the epidemiology of our country. This may seem utopian, considering the time and expense involved. However, a potentially assured annual consumption of 100 million doses (25 million births × 4 doses; 3 primary plus booster) would attract manufacturers. This would also spur indigenous production which should be the goal, since dependence on importation will not be feasible in the long-term. As for other vaccines, highlighting an annual requirement of this magnitude can be an effective tool to bargain for an appropriate price.

Thus, pneumococcal vaccine is worth considering in India for universal vaccination, but neither of the currently available vaccines is appropriate. A possible way forward has been presented herein.

Joseph L Mathew,
Advanced Pediatrics Center,
PGIMER, Chandigarh 160 012, India.
Email: [email protected]