Peltzman Effect has been termed after Sam Peltzman, an economist at the University of Chicago, who first described it in 1975. According to the theory, when safety measures are mandated, people's perception of risk decreases, making them take riskier decisions.

 

Peltzman postulated about mandating the use of seatbelts in automobiles, leading to more accidents. It implies that safety perception increases risk appetite. In other terms, people become more careful when they sense greater risk and less careful if they feel more protected, according to his theory.

 

Similarly, in the case of Covid-19, vaccines are giving a sense of security, leading to increased risky behaviour, that is low adherence to preventive measures -- mask usage, social distancing and hand sanitisation.

 

While it is a known fact that vaccines neither give immediate protection or full protection (against infection as against death), the sense of security unfortunately starts much earlier, even before the actual injection: people wear masks with less caution, do not maintain distance as soon as they reach vaccination centres -- the Peltzman effect.

 

The increase in the number of people being innoculated gives rise to a "misplaced sense of security in 'herd immunity' long before widespread immunity is truly present," said doctors from New York University's Langone Health in a comprehensive review of the Peltzman Effect, published in the ACP Journals on March 2.

 

As a result "...the very optimism that is necessary to encourage widespread acceptance of the vaccine will undoubtedly contribute to the overconfidence" and lead people to forgo the preventive measures.

 

"Consciously or not, even those who have not received a Covid-19 vaccine may forgo masks and social distancing if they know that others are receiving the vaccine," the doctors added.

 

Although pandemic fatigue is a reason for low adherence to preventive measures, the Peltzman effect cannot be ignored. The theory is also evident in the drastic decline in the usage of PPE kits by the healthcare workers.

 

This risk-taking behaviour can be dangerous for general public. But for a health care worker dealing directly with Covid-19 patients, it can prove detrimental and impair the health care services, as is seen in the recent report of 37 doctors in a Delhi hospital testing positive even after taking both doses. The doctors, reportedly, got infected while attending to Covid-19 patients at the hospital.