Techno tracks

New vaccines are creating new choices and dilemmas. They are also changing the global balance of powerThe technology for developing new vaccines and the research that goes into it is becoming increasingly sophisticated and dependent upon an enormous corpus of funds to get off the blocks. This is raising important issues relating to pricing, access and international equity.

Take the flu vaccine -- an important product given the global scare over an impending avian flu epidemic. The old method for producing a flu vaccine involved injecting the virus into chicken eggs from where it could be harvested. This method was cumbersome, long-winded and unlikely to provide sufficient doses of vaccines to fight epidemics. Manufacturers are now trying to use cell cultures to grow the virus. Maintaining the infrastructure for storing and culturing cells is significantly more expensive. In this case, that's a price that has to be paid -- if the epidemic strikes.

The technological implications in the case of the dtp vaccine are slightly different. The older vaccine used cultured cells of the pertussis bacteria to make the vaccine. In the new process, the relevant antigen is extracted to make the vaccine. Though debated, the advantage of the latter is that it is safer. The disadvantage is that the process is more complicated and the vaccine produced thrice as expensive. The West has shifted to the acellular vaccine, but India, like most developing countries, still uses the older vaccine. But it can't be assumed that this situation will not change.

The case of hepatitis B is somewhat curiouser. It uses a 'renewable' resource -- yeast. The gene from the virus is introduced into the yeast. After that, the yeast continuously produces the antigen from which the vaccine is made. The basic raw material, in other words, is free after a point. You'd think that would make the vaccine cheaper. You would be wrong: defying economic logic, manufacturers are extracting superprofits on the grounds that this vaccine and technology is new.

Even technologies of administering vaccines are becoming more sophisticated. In the pipeline are heat-stable vaccines, jet injectors, aerosols and patches. These are crucial for India's delivery systems and indigenous investment into developing them are essential.