“It’s great news we have two possible vaccines against COVID-19 that are likely to start rolling out soon, and a third in the wings,” says Dr Flavio Toxvaerd. “Many people are focussed on the benefit from the inoculation. However, what they may not be aware of is how having a vaccine against the infection on the horizon may change people’s behaviour.”

The research suggests how people will behave, when it is likely they will receive a vaccine. Counter-intuitively, it may actually make the impact, and the effects, of the pandemic worse in the short run.

“To benefit from the vaccine, a person must ensure that they keep safe from infection until they are vaccinated,” he says. There will be tighter rule adhesion, as initially the public are more ready to accept social distancing rules. “People’s incentive is to increase efforts to self-protect, and therefore gradually ramp up social distancing as the vaccine’s arrival comes closer.”

This means that as the vaccine’s release approaches, people may show increasing unwillingness to be socially active, share public spaces, eat out or to show up at work. Important knock-on economic effects are likely, as many businesses rely on physical proximity to make a profit and for employees to show up to work to be able to function effectively.

However, once the vaccine is being distributed, people who are inoculated let down their guard, and that can lead to others doing likewise.

“If it is rolled out in phases, there is a danger people will let down their guard too early,” he cautions. “In effect, a percentage of the population think they will get a free ride, because others are protected. It is not a licence to ‘cash in before its time’,” he says.

Dr Flavio Toxvaerd, an economist specialising in economic epidemiology at the University of Cambridge Faculty of Economics, and a Fellow of Clare College along with Professor Miltos Makris, from the University of Kent have published a working paper though the Cambridge-INET Institute.

The new paper analysed social distancing behaviour in a model where medical innovations, such as a vaccines or effective treatments, are anticipated by the public.

The full paper "Great Expectations: Social Distancing in Anticipation of Pharmaceutical Innovations" is available at:
http://www.econ.cam.ac.uk/research/cwpe-abstracts?cwpe=2097 - Cambridge Working Papers in Economics
https://www.inet.econ.cam.ac.uk/research-papers/wp-abstracts?wp=2046 - Cambridge-INET Institute Working Papers