Our record against viruses that change strains has been poor and patchy    

Some vaccines for some diseases, it is true, are milestones in the history of medicine. An almost Polio-free world and the complete eradication of Small Pox have been possible because of vaccines. But on the other hand, although millions of flu shots are dispensed over the counter in western countries every season, the efficacy and utility of the vaccine remain questionable.

A vaccine is actually the virus itself, in an attenuated and calibrated form, reducing the virulence of the virus and degree that will cause antigenic memory in the person immunised. It is stored in the immune system as a memory (antigenic memory) that gets activated on any future exposure to the same virus and produces antibodies to kill the virus before it causes any harm. This is why people who have recovered from the infection, or who have been vaccinated, develop immunity to future infections with the same strain of virus.

The vaccine produces immunity through the immune system. People with compromised immune system mount a poor immunological response to the vaccine and, therefore, derive less benefit from the vaccine. While these are the vulnerable people who need to be protected, paradoxically the vaccine is less likely to be effective for people who need it the most. Viruses are of two types- DNA (such as vaccines for small pox, chicken pox etc) and RNA (such as Corona viruses, seasonal flu and Dengue). While all viruses replicate (divide) themselves for propagation, single strand RNA viruses are notoriously prone to errors in their replication (mutation) which can change their character considerably. This is the reason why very often by the time a RNA vaccine is developed and ready, the strain of the virus has mutated itself to a different antigenic entity, rendering the vaccine ineffective and the entire exercise futile.

Historically, success has eluded us in our bid to develop vaccines against RNA viruses. Small pox (Variola virus) and Chicken pox (Varicella) are DNA viruses. Amongst RNA viruses, there is a vaccine against the seasonal flu virus, but it still cannot prevent, annually, half a million deaths due to seasonal flu across the world.

Each year, World Health Organisation (WHO) and the Centres for Disease Control and Prevention, based on their data from across the world on viruses in the preceding year, issue a forecast about which viruses are likely to circulate in the ensuing winter.

Accordingly, in February every year, the manufacturing process begins for a vaccine that includes the three most likely strains for the next season. Before the ensuing winter about one in every three Americans gets vaccinated. Yet flu takes a yearly toll of 40-60 thousand lives in USA. During the year 2004, vaccine production fell behind, causing a 40 per cent drop in immunization rates. Yet mortality did not rise.

In 1968 and 1997, the vaccine that had been produced for certain virus strains, became ineffective by winter when the virus had mutated to an altogether different strain. Technically it amounted to no vaccination. Yet death rates from all causes, including flu and the various illnesses it can exacerbate, remained the same during the flu season.

Sumit Majumdar, a physician and researcher at the University of Alberta in Canada, offers another historical observation. “Rising rates of vaccination of the elderly over the past two decades have not coincided with a lower overall mortality rate. In 1989, only 15 percent of people over age 65 in the U.S. and Canada were vaccinated against flu. Today, more than 65 percent are immunised. Over the years the flu death rate per million population has remained more or less the same in spite of the significant rise in the number of people immunised.”

Dr Tom Jefferson, an epidemiologist of global repute, was appointed by the Governments of UK and Australia to review the evidence and give recommendations about prevention and treatment of Flu. He was also lead Cochrane (Global repository of highest level of evidence in the field of medicine) investigator for efficacy of flu vaccination.

A controlled trial was recommended but the establishment did not appear to be willing to oblige. Jefferson found this ridiculous: “What do you do when you have uncertainty? You test…we have built huge, population-based policies on the flimsiest of scientific evidence. The most unethical thing to do is to carry on as business as usual.”

The scientific community remains divided about the efficacy of this vaccine. As in any walk of life, in medicine too swimming with the tide remains more conducive to survival and career promotion than the perils of swimming against it.

Anthony Fauci (a household name these days), the director of the National Institute of Allergy and Infectious Diseases at the NIH, where much of the basic science of flu vaccine has been worked out, says, “I have no doubt that it is effective in conferring some degree of protection. To say otherwise is a minority view.” That to some extent is admission of a basic flaw. Is science about concrete evidence or about the prevailing majoritarian view? Is scientific truth, like religion, a matter of faith?

The answer to both questions sadly, is yes.

This is not anything new in medicine. About a century ago, in 1925, Sinclair Lewis in his Pulitzer Prize– winning book Arrowsmith, derided the medical culture that allowed belief and profits to distort science. Based on the lives of the real-life microbiologists Paul de Kruif and Jacques Loeb of Rockefeller Institute, the book is the story of Martin Arrowsmith, a scientist who invents a new vaccine for bubonic plague at the peak of a devastating epidemic. But he is not allowed to test the vaccine’s efficacy and safety by a desperate community that believes the vaccine will work, and a profit-oriented institute that rushes the vaccine into use prematurely—forever pre-empting proper studies that are still needed to validate the use.

Writings on the wall are bold and clear. The ‘Corona vaccine’ will hit the market with a bang. And then the entire eco system will conspire to keep the belief alive and in currency. President Trump has already vowed to get a vaccine by the year-end, much to the consternation of scientists. But then that is life. This is certainly the time to invest your last Rupee in stocks of vaccine making enterprises.

Finally, I can’t help myself from quoting Adam Smith. He had famously and presciently said, “it is not from the benevolence of the butcher, the brewer or the baker that we expect our dinner, but from their regard to their own interest. We address ourselves not to their humanity but to their self-love, and never talk to them of our own necessities but of their advantages”.