To Fight Covid-19 Is To Fight Its Lightning Transmission
Rajan Philips
The consensus within the medical scientific community cannot be clearer. There is no medication to treat the Coronavirus Disease of 2019 (COVID-19). And there is no vaccine to prevent it. The only weapon against the disease that is available for the next several weeks, even months, is to reduce or prevent community transmission of the virus. All the data on human to human transmission of the virus indicates that transmission occurs primarily through respiratory droplets from coughing and sneezing between individuals in close contact. And transmission is also occurring at significant levels through ‘asymptomatics’, virus carriers without any symptom. Therefore, social isolation is the only way to prevent disease transmission in the foreseeable near to medium term.
The scale at which isolation should be conducted in every country is astounding and unprecedented. The effects of such isolation will be crippling on national economies and the world economy as a whole. Governments everywhere are facing two massive challenges, and all at the same time, like never before. Governmental capabilities and capacities to respond to the twin challenges vastly differ from country to country. Different countries like China, Italy and South Korea, with large numbers of caseloads have tried different degrees and methods of isolation with dramatically different results. The US and the British governments took too cavalier an approach to COVID-19 for too long, and are now scrambling to stem the inevitable surge in the number of cases that is widely expected.
Sri Lankan authorities too were showing signs of nonchalance, bravado, and political calculations, but learnt their lesson rather quickly, in a matter of three days. After summarily rejecting calls to postpone the April parliamentary elections, the authorities hurriedly decided to postpone them indefinitely soon after nominations closed. And after spurning suggestions to implement a national clampdown to enforce social isolation, the government declared emergency and imposed national curfew over the weekend from Friday evening to Monday morning. The government has also banned pilgrimages, tours and leisure trips, called upon people to maintain a safe one metre distance between them, and ordered trains and buses to restrict passenger loads to half their seat capacity. These are all positive and necessary steps, better than the native bravado that no restrictions are necessary when war winners are in command. But much more needs to be done and consistently to prevent an exponential rise in the number of cases in Sri Lanka.
The global and national increases in the number of cases over the last week (13 March to 20 March) are scary. The global total has doubled from 136,875 cases to 276,113 cases and 11,400 deaths. Only China and South Korea are showing some stabilization, around 81,000 and 8,700 cases, respectively. Everywhere else, the virus has gone exponential. The dramatic increases are in Western Europe, and the US total has risen from 1,264 to 19,640. South Asia, South America and Africa are no longer the spared oases they looked last week. India is up from 81 to 258 while Pakistan has vaulted to 501 from 20. Bangladesh (3 to 20) and Maldives (8 to 13) are holding steady for now. In Sri Lanka, the number of known cases has worryingly multiplied from 3 to 73 in one week. More worryingly, there are reportedly unaccounted arrivals from overseas before the current airport restrictions began, and who might potentially be virus carriers within the general population.
Having great doctors and good hospitals is not enough in any country if the coronaviral disease surges beyond the country’s overall healthcare capacity. The healthcare problem for Sri Lanka is not the quality of its professionals but the capacity of its healthcare infrastructure. If the number of COVID-19 cases is allowed to increase to the point of overwhelming its healthcare capacity, the country will be in deep trouble. The system will have to cope with not only increasing numbers of COVID-19 patients, but also normal patients requiring hospital treatment.
Given the relatively high proportion of elderly in the population, it will be a challenge to protect them from the virus and then treat them if they get infected. Limited capacity and overwhelming demand would mean doctors will be forced to perform the dreadful task of triaging – deciding the order of allocation of beds, especially ICU beds, among a large number of patients. And doctors and nurses will end up getting infected and worse. These are not scare stories but are already happening in Italy and in Iran.
Flattening the curve
There is an amazing array of scholarly scientific writings dealing with practically every aspect of the coronavirus that is appearing literally online and in real time. The two graphs below are among the hundreds that are in circulation, illustrating the now universal mantra of ‘flattening the curve’. They are based on simple mathematical models and are useful in illustrating the concept and its consequence for healthcare capacity.
The above set of graphs illustrate how the number of COVID-19 cases will rise, peak and fall under three conditions, viz., without any slowing down of disease transmission, with transmission reduced by 20%, and transmission reduced by 40%. Reducing the spread of the disease lowers the maximum number of cases while extending the duration of the epidemic, to manageable levels.
The below set of graphs shows what is manageable. By slowing down the disease spread, the maximum number of cases in a country, or in areas within it, can be brought within its healthcare capacity – the number of hospitals, beds, ICU beds, care workers and professionals, and equipment. The failure to arrest the disease early on led to surges in China, Korea, Italy and now other West European countries, overwhelming their healthcare capacities. While China and Korea may have, hopefully, seen the worst off, others in that league are still struggling. Italy, especially northern Italy, has not been able to stem the spread at all despite a national shutdown for now over two weeks. Last week, Wednesday alone saw 4,207 new cases and a one-day death toll of 475. The highest single day national death total since the outbreak started in China. On Friday the daily death toll went past 500, a second record in two days.
