In 1917, the US Bureau of Animal Industry was worried about a mysterious cattle infection killing unborn calves. It realized that a cow that had an abortion was highly likely to become immune to it, calves born and raised in such an affected herd had tolerance of the disease, and so the phrase ‘herd immunity’ took birth. As the covid pandemic engulfs the world in wave after tsunamic wave of sickness and death, the only light at the end of this tunnel seems to be humans achieving vaccine-induced herd immunity. The rapid development of covid vaccines has been the biggest triumph of science in recent times. A combination of fundamental research in mRNA, the marvel of gene sequencing and the instant availability of data off the internet gave the world a new kind of vaccine within a year of the disease’s global outbreak.
But even as the world strives for elusive immunity, the question of how to vaccinate almost 8 billion people as rapidly as possible has not yet been answered. There are multiple obstacles to vaccinating the proportion of our population needed to achieve herd immunity: the production of enough doses, their logistics and transportation, and affordability. Good protocols on who needs to be immunized earlier and systems to track the vaccinated need to be created. Privacy issues around health records and demographic identity need to be addressed. Often, social and religion-based resistance needs to be overcome, and people need an incentive to be vaccinated. Additionally, it is not enough to vaccinate an entire country, or even an entire continent. Viruses mutate rapidly and cross oceans with remarkable ease.
Title image: freepik.com