Covid 19: A behavioural perspective

I wrote a number of posts and one research paper on the Covid 19 pandemic. I wrote about the epidemiological patterns, evolution of the virus and the need to change the strategy according to the changing context. Most of what I thought is coming out to be qualitatively true. Now there is genomic data showing a large number of mutations, signatures of positive selection on the mutations and the signs of reducing virulence. The fatality continues to come down. India today news on 1st Sept says that in a joint statement, experts of the Indian Public Health Association (IPHA), Indian Association of Preventive and Social Medicine (IAPSM), and Indian Association of Epidemiologists (IAE) advised the government to lift lockdown, reopen schools and colleges and not to rely too much on vaccines. In the month of May it looked like I was the only one saying this. Now there are “experts” saying the same.

But epidemiology and pubic health is not my core interest. My core interest is behavior. The pandemic was a unique and rare opportunity to observe different patterns of behavior. Human behavior invariably interacts with the virus. Behavioural patterns are shaped by the epidemic and behavior in turn shapes the course of the epidemic, even the biology of the virus. Optimizing one’s own perceived cost-benefits is an innate human tendency. Every player has a different cost benefit calculation. The perception of costs, risks and benefits are also shaped by different factors and that is a complex and interesting dynamics.

People perceive risks by what they see as well as by what they are told. There are many other examples where public health authorities have been warning people about various risks. Tobacco is a very good example. The statistical association between tobacco and cancer is consistently seen. There is enough awareness among people, warnings are prominently printed on every packet. But there are no signs of the market for tobacco going down in any form. The reason why people do not listen to the public health authorities is that there is a conflict between what they see and what they are told. People have their own intuitive sampling strategies and built in statistical algorithms by which they make their own inferences. Often they are different than the public health policies.

The health science literature projects odds ratios, risk ratios or hazard ratios to reflect the risk from a given factor like tobacco. These are essentially probability ratios of some kind. We conducted a small study of how people perceive risks, which is yet to be published but the results are extremely clear. We observe that people infer risks based on probability differences and not on probability ratios. We saw that even statisticians and public health personnel, who have been formally trained to use the ratio based indices, use probability difference when they have to make a behavioural decision for themselves in a game or imaginary context. The ratio based and difference based inferences can be diametrically opposite at times. If say among non-smokers the risk of cancer is one in thousand and in smokers one in hundred, smoking can be said to increase the probability of cancer ten-fold, but the actual increase in probability is only 0.009.  While the health authorities project the ratio, people’s intuitive sampling and statistical inference methods seem to have evolved to use the difference. The probability ratio is large but difference is small. So the risk of cancer fails to prevent smoking.

This applies to the risk perception for Covid-19 as well. Initially people did not have any opportunity to sample themselves. So they believed what they were told. As they started observing cases around them, a mental conflict started building up in their subconscious mind. They were told it’s a deadly virus but their subconscious sampling did not show that. What can be the effects of such a conflict? I feel it leads to an internal behavioural contradiction. While at a subconscious level the fear starts vanishing, at a verbal level they will still express fear. So in a questionnaire survey majority will agree that it’s a deadly virus and the pandemic is unprecedentedly dangerous. In reality, as soon as beaches, theatres and other public places are opened up they won’t mind crowding there. This has happened throughout the world, independent of the literacy, education, economic status of the society. This is because the risk of death by catching the infection, inferred by probability difference is very small and people calculate the risks by their own innate Bayesian algorithms. In India, with a population approaching 140 crore, living with a mean lifespan of 70 years, there are around 55,000 deaths expected every day. Covid deaths during the last two weeks appear to have stabilized at around 1000 per day. This means the death probability on a given day has increased from 0.0000393 to 0.00004. That is .0000007 per day or .00026 per year. Even if we make a limiting assumption that lockdown and masks make the probability of infection zero, the difference between following and not following preventive measures is too small to care. For a difference of this magnitude, people will not be willing to sacrifice their livelihood as well as pleasure activities. Therefore unless a lockdown in forcefully imposed, people are most unlikely to follow it. It is not ignorance, it is innate statistical calculations. “Creating awareness” will not work because people’s calculations directly contradict the preaching. However, more than the fear of infection or death, the social norm matters more. More people wear masks for the fear of punishment or to avoid strange looks by others than for the fear of infection. There is one more reason. For a large number of people the thought of getting admitted in an isolation ward, cut off from friends and relatives matters more than the fear of death.

In a cost benefit calculation, people innately differentiate between absolute and relative costs. For relative costs, if everyone is suffering to a similar extent, people don’t mind their own suffering. For absolute ones, others don’t matter. For example, for an addict, missing alcohol is an absolute cost. On the other hand, kids missing school is a big cost with long term consequences but it is perceived as a relative cost. My kid missing school is ok if all kids are missing it. So obviously there would be more pressure to start wine shops than starting schools. If parents are resisting reopening of schools for the fear of their kids getting infected, their resistance will persist as long as they can prevent reopening of schools entirely. But if other kids are attending, the cost of only their kid not attending becomes larger than the fear of infection. So if some schools start, all others will start with little resistance from parents.

Doctors and hospital staff, unlike common man, invariably have a biased sample. They see the serious cases disproportionately more frequently. So the risk in their perception will always be more than one in common man’s perception. Here again there will be a difference between a general practitioner and a Covid ICU ward intensivist, the latter having a much more biased sample.  So although a doctor’s knowledge needs to be respected, the statistical inference of common man is equally valuable because it is less biased.   

Health authorities and governments have a perceived ‘responsibility’ of people’s health. Under the pressure of such responsibility it is necessary to show that you have done something. Therefore they will prefer to do things that show up prominently. Whether the measures taken are really effective or not is a secondary concern. The primary concern is to minimize attracting criticism. This is a major force shaping the strategies of the health administration and government. A lockdown is a preferred response since it shows off more strikingly and is easier to implement than providing better patient care, inculcating clean habits in the society, taking better care of pollution, caring for of garbage handlers etc.

The vaccine and drug industry clearly has a commercial interest. They will always be bent on painting a fearful picture of the disease. They can do so successfully but only to a limited extent. They cannot stop people’s subconscious statistical inferences. As the perceived fear goes down inevitably, the market potential for vaccine will also go down. Nevertheless, people will go for a vaccine if it is free of cost or cheap enough and easily available. If it is costlier than the perceived fear, they won’t.

The behavioural basis of costly drugs with unproven or marginal benefits lies in the social norms of demonstrating that you did all you could to save your relatives. This is not to deny love. It certainly exists. But by the social norms, only loving your relatives is not enough. You need to demonstrate that to the society. Costly drug is one of the best ways to do that. The pharma industry knows this quite well and makes good business on it. People will be ready to spend huge amounts if one of their relatives or friends is under critical condition. Here the actual probability of saving the person does not count so much in the cost benefit calculation. To establish that you care more about someone than you care for money is important. If only the outcome mattered, then only the drugs with proven large benefits would have been in demand. But since the social display matters, the efficacy of the drug counts little. That’s why clinical trials of drugs often show contradictory or marginal benefits, but all drugs are sold at a very high price.

The research community has its own interests too. A pandemic is a good opportunity to get quick publications, make headlines and seek more research grants. Therefore this community will be more interested in spreading terror. It has been repeatedly seen that whenever someone made a more realistic statement, he or she was immediately and heavily criticized. There is a very clear declining trend in the death rate globally. But researchers have rarely ever talked about it. Saying that the virus is not as deadly as perceived earlier is politically incorrect and it would be rare for a researcher to say so. When data show a declining death rate, they will not analyze or reason it out. They will simply ignore it. The best example is that of Sweden. Sweden took a different path and did not impose a lockdown. Initially the death toll was high. There were heated debates on whether Sweden took a suicidal path. But today Sweden’s death rate has declined by an order of magnitude even without a lockdown, so it is natural that nobody talks about it.

So far I have tried to predict what the expected behavior of different players is, with no value judgment. I am not saying someone is right or wrong. This is what baseline selfish behavioural motives will be. Conscious decisions overriding the innate tendencies are not impossible. But you don’t expect everyone’s virtue to be the same. So modal behavior is most likely to follow what I described. There can always be glorious exceptions.

However, as a student of science, there is one issue where I would like to bring in the ‘right-wrong’ judgment. People believe in science and scientists to a large extent. This trust is valuable and needs to be maintained. So I would urge scientists not to play ostrich and openly admit the obvious trends in the data and change the strategic advice accordingly. We have seen during the pandemic that so often irresponsible statements were made and retracted. Having different views is a good sign. Looking for evidence for or against a viewpoint is also fine. But we have seen that statements were often retracted under conformity or political pressure. For science, only sound theory, models and evidence matters. At times, being wrong is not a crime, but if and when evidence shows that you are wrong, admitting and correcting oneself is necessary. If this is not done, people will lose faith in science and in scientists. This is particularly important for the fact that mainstream health organizations have largely kept mum on the declining fatality rate. O many people have lost their livelihood because of the fear of the virus. If they know eventually that the fear was overblown and scientists never admitted that, they would lose trust in science. If people lose trust in science or in scientists, what can be a bigger social tragedy? What will be the future course if people continue along their innate behaviours? Biologically, the virus will go on becoming milder, but will not be eradicated for quite some time. It will stay in the population more peacefully for at least a few more years, being just another virus. But even if it remains at its current virulence, gradually the seriousness of the disease in people’s perception will vanish. Health authorities may not admit this clearly but they will talk about the seriousness of the disease less and less frequently and ultimately stop talking about it. In the news channels and media, the news value will keep on diminishing until nothing is perceived as worth reporting. There are talks about fundamental and permanent changes brought about by the pandemic, but that is less likely. A few practices might become irrelevant rituals and persist for the name sake. Ultimately most good and bad things are most likely to return to the baseline, as if nothing had happened.

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