Pandemic mitigation is the next stage in responding to a pandemic. Usually, this is undertaken when there is evidence of community transmission- a large number of cases are not linked to any known case (it is not possible to determine how the person acquired infection).
Here, the focus shifts from contact tracing and disease surveillance to broader measures, since those measures now have limited utility. Measures are directed at reducing transmission, and broadly include:
- Curtailing interactions between infected and uninfected populations
- Mobility restrictions
- Socio-economic restrictions
- Physical distancing
- Reducing infectiousness of symptomatic patients
- Hygiene measures
- Treatment (antiviral/ antibiotic)
- Reducing susceptibility of uninfected persons
The basic idea in mitigation is that reducing cases to zero is unlikely, so one attempts to spread the number of cases over time in the hope that it will reduce the burden on the healthcare system (‘flattening the curve’).
Given that COVID-19 is transmitted through droplets and aerosols, the consistent use of masks, maintaining physical distance (1.5-2 metres), and judicious use of containment measures (like when there is a cluster of cases) are likely to be beneficial. However, more stringent and prolonged restrictions may be counterproductive- travel restrictions for influenza pandemics are not effective unless initiated when there are less than 50 cases at the site of origin. Socio-economic restrictions like school closure were not cost-effective in high-income settings in the 2009 influenza pandemic:
The above values may not hold true for a resource-limited setting, especially where school enrolment is low and family members are available to look after the children at home.
The presence of an effective treatment or vaccine is likely to reduce costs by enabling economically productive activities without increasing disease burden. A case in point is HIV/AIDS- the availability of an effective treatment has resulted in better health outcomes and survival despite limited change in human behaviour. In the absence of either effective treatment or vaccine against COVID-19, our only option is to reduce interactions and infectiousness by maintaining physical distance where possible, and use PPE consistently.
I do not favour ‘lockdown’ as a public health measure for mitigation. For one, lockdown is inappropriate for mitigation- there are a large number of unexplained/ unlinked cases (community transmission). Given that a large proportion of cases are asymptomatic/ pre-symptomatic, a lockdown will likely increase transmission by ensuring close contact within families/ closed spaces. Second, there is no convincing evidence that lockdowns work- evidence is anecdotal at best. In fact, there is clear evidence that lockdown does not work- despite implementing the world’s largest and longest lockdown, India has not witnessed a decline in cases at any point during the lockdown (there was a minor dip just after lockdown was announced, but it was not attributable to the lockdown). Third, a lockdown shocks the economy and causes significant social disruption. I cannot justify the economic and social costs given the observed effect of lockdown on the pandemic. Perhaps the only situation wherein a lockdown would be acceptable is early in a pandemic, when the state/country has very few cases, all of whom have been identified and placed under isolation; their contacts have all been traced and placed under quarantine; borders have been sealed; and the government wants to stockpile equipment/ medicines, etc. Even then, a detailed plan should be drawn before announcing the lockdown, and people should be given reasonable time to stock up on essentials. Preferably, pandemic insurance should be available to transfer risk. Else, social security measures must be in place before implementing a lockdown. These are necessary to minimize collateral damage due to the lockdown.
A summary of various measures is provided in the table below:
These measures are only as good as their implementation- with poor implementation none of these measures will yield benefit. In many democratic countries/ states, people are defying and aggressively resisting attempts to impose use of PPEs, physical distancing, restrictions on mobility, etc. This presents an ethical challenge- does one restrict or ignore individual autonomy/ freedom in pursuit of what is considered good for the population, or does one uphold individual liberty and permit individuals/ communities to behave in manners that may put the health of others in jeopardy?