… and what can we do about it?
If we plot the total number of new covid19 cases in India over days, we see a pattern such as this:
This is by now a familiar story where we see a sharp rise in the number fo cases starting somewhere in March of 2021, rapidly overtaking anything we have seen so far. If we view the slope as well, we see the sharpness of the rise in the number of cases from a year ago, when it was rising gently. The number of people who have died have also risen sharply over this time.
On the other hand, if we were to now dissect India’s number of cases based on how many cases are there at the time per state of the union, we get to see a figure as follows (this figure is not very current, but it represents the number of cases as of end of April, 2021)
This is India’s COVID19 case distribution across the states till about the beginning of May (the numbers have changed since). We have plotted the total number of cases over States where they occur. If we consider about 548 districts in the country for which data are available and plot them, we get the following:
This is even more pronounced in that, we can see that only a few districts in the country can account for the high rise in the number of cases. If we drilled further (and we haven’t), we can expect that at household level, we would see a similar pattern. This essentially tells us that a few people, say 10% of the population accounts for roughly 80–90% of the infection. On the one hand, this may seem like counter-intuitive, on the other, this has several implications for public policy and actions that the people and the government can adopt to control the apparently runaway pandemic.
Over the last one year, we have also learned several things about the patterns of this pandemic and the nature of sars-cov-2 infection.
First, we have learned that COVID is airborne (for an excellent discussion about this issue, read this excellent paper). More importantly, rather seen acknowledgement from the WHO and CDC and other agencies that pretty much help to control different country’s responses to pandemic that COVID is an airborne pathogen. This also implies that COVID is BOTH airborne and spreads via droplets and therefore there is all the more reason to be careful about COVID’s mode of spread. So, instead of only maintaining a two meter social distance, and hand-washing, our focus of control has now shifted to maintaining good ventilation, wearing masks, preferably two masks at all times including in public transportation, getting fresh air and going outside.
Second, and in accordance with this pattern of airborne transmission that we have learned, that avoiding what the Japanese public health professor Hitoshi Oshitani has often referred to as “3Cs”, i.e., crowd, closed spaces, and close-contact.
Third, because of this, reverse or retrospective contact tracing has gained momentum in many parts of the world, including Japan and New Zealand. Here, instead of going forward, countries have pushed for tracing to track the origin of people from where the infection first spread and tighter cluster control. An excellent guide and a method paper is available from Harvard, see:
Unfortunately, in India, there is no evidence anyone is seriously considering these things. While the infection continues to rage, election rallies were organised, religious fairs went on business as usual, and the country relied only on medicines and remedy. This does not work for a disease that only responds to preventive measures.