The lockdown has achieved its purpose. Extending it may not be worth the cost.
By Ramanan Laxminarayan
In a series of interviews in the middle of March, I had noted that given the state of preparedness of the country’s healthcare system to deal with Covid-19, and the projected flood of cases if the disease were allowed to transmit freely, a lockdown was essential. A three-week lockdown was essential to push out the epidemic curve to June 2020, by which time the country could prepare adequately for the disease. While I was personally in favour of focused state-level shutdowns rather than a national shutdown, keeping in mind the economic and human costs involved, there may have been political and logistical challenges in communicating different messages to different parts of the country. So here we are a month into the big lockdown.
So, what all have we achieved with the lockdown?
Our projections on April 13 on the effect of the lockdown indicated that we should expect to see about 100,000 infections on April 24 (this includes asymptomatic and mild infections). This is about five times higher than reported cases, which is appropriate given the rate of undercount and the fact that most asymptomatic infections are missed given the low testing rate. The number of infections would have been about eight times as much without the lockdown. The rationale for enforced distancing that lockdowns enable is that they temporarily reduce the transmission of infection, which then slows the speed at which an exponential curve can take-off. The mathematics of this can be explained crudely as follows.
Without a lockdown, the number of Covid-19 infections was projected to double approximately every three days—roughly the rate that other countries have seen without a lockdown. At this speed, it takes only 66 days to get from 100 infections to 420 million infections. That is the power of exponential functions. Our models showed that under the assumption that we had the first 100 infections by early March, we would be looking at the epidemic peak by May.
With an unprepared health system, there was no way that the country was ready to take on a peak that early.
The logic of a shutdown was that if we were able to increase that doubling time from three to eight days (what we had expected with enforced distancing) for a three-week period, then we could purchase another three to four weeks of time to prepare. And if the lockdown was able to induce a longer-term behaviour change in the population such that they take the disease seriously beyond the lockdown period, we would get an additional six weeks (assuming that the doubling is only every five days when we return from lockdown).
The mathematics in disease models is a bit more complicated than what I have explained here because of how transmission dynamics work, and how we build up immunity as a population as we go along. But the fundamental power of exponential curves remains. Even with a very conservative assumption of just 1% of infections requiring critical care (the actual proportions are higher in other countries), we would have been looking at millions of hospital beds, far more than was available in the country.
The purpose of the lockdown was only to buy time. Since March 24, the rate of testing has increased from under 2,000 per day to over 36,000 at the current time. According to the government’s reports, we are now prepared with thousands more ICU beds, supplies of personal protective equipment, organisation of healthcare professionals, clinical protocols and other equipment for critical care.
All of this preparedness planning should undoubtedly continue. However, each additional day of lockdown is now much less valuable in terms of our ability to prepare and, in effect, we are pushing out the epidemic peak only a little bit. Are the benefits worth the costs? In human terms, the consequences are enormous in terms of lost jobs, localised shortages of food and the suffering of the migrants and homeless. Companies have lost significant revenues and will have to lay-off workers. The transportation industry is in shambles, as is the construction industry. The firm Acuité Ratings & Research estimates that every day of lockdown costs the country about `35,000 crore ($4.5 billion). That works as a crude approximation given that about half of the economy of $3 trillion is not functional and assuming about 330 working days. The daily value-add of additional preparation is certainly not anything close to `35,000 crore.
We could end the lockdown now and spend the additional government revenues from the revival of the economy on increasing testing, containment, hospital beds, critical care and messaging on carrying on distancing. We can achieve much more through continuation of bans on mass gatherings, covering mouths and noses in public, spitting bans, physical distancing to the extent possible in markets, and expanded testing. That would mean no movie theatres, and no large weddings, religious gatherings, sporting events or other social events. Increased testing is the mantra simply because it enables those who are infected to know their infection status and, therefore, to protect their families and community.
Reducing stigma related to Covid-19 is a high priority. If we treat Covid-19 patients like criminals rather than victims of a condition they had no control over, we will find that people will not come forward to be tested. There may be some who think that the lockdown is all that is needed to control Covid-19 and when cases start coming down, we can end the lockdown and we can resume as before. That, sadly, is not likely to happen. The virus will continue to spread, with or without lockdown, albeit at different rates. And as testing increases, we will uncover more cases. There is simply no way to stop the epidemic in its tracks.
The national lockdown was timely and important. It came on the back of early action that India took to stop flights to China, close borders, and trace and quarantine foreign travellers. All of these helped slow down the disease, along with the big lockdown. But the lockdown has achieved its purpose. There is no added value and it is time to go back to work, albeit with some important safety measures. We may yet need another lockdown or two before the end of the year to curb the sharp rise of the disease, and it is important to keep some powder dry for these situations.
However, it is how we effectively control disease transmission and maintain infection prevention and control behaviour post-lockdown and not the continuation of the lockdown that will determine the future trajectory of Covid-19 in India.