Use epidemiology as a tool to fight Covid-19 | Opinion – analysis
A highly qualified clinical specialist recently said that epidemiologists are busy projecting numbers because that’s what they do. This is a misleading assumption. Epidemiologists aim to prevent and control disease epidemics. Epidemiology, as defined by our doctoral mentor, Dr. Roger Detels, is the basic science of public health, because it describes the relationship of health or disease with other health-related factors, such as human pathogens, in human populations. The crisis caused by coronavirus disease (Covid-19) is a good example to show that, if the epidemiology is not properly understood, it can have lethal consequences.
Countering the adverse impacts of Covid-19 requires two types of measures: Containment and mitigation.
Consider, for example, the absolute load of cases as a large balloon. Containment, in this case, refers to the amount of air added to the balloon, while mitigation means controlling the rate at which the air is filled. To avoid pressure on the public health system with limited resources, our goal is to ensure that the globe is never full.
Containment ensures that we detect all those infected with Covid-19. Once they are identified, they are isolated and their contacts are properly identified and monitored. This process is known as quarantine, and after the quarantine period has passed, they are not likely to be infectious.
Mitigation refers to slowing the spread of the virus in the community by making it difficult to attack susceptible populations. It is important to stress that both containment and mitigation processes are equally necessary to ensure that the disease balloon does not explode.
For effective mitigation, Prime Minister Narendra Modi called on the Indians to remain in their homes for the next 21 days. This blockade has the potential to phenomenally alter the course of the pandemic, by effectively mitigating it.
Our next challenge is the containment of Covid-19. India’s inability to detect and isolate cases effectively hinders this process. Instead, we need what we call the syndromic approach. Consider all cases with fever, cough, tiredness, or shortness of breath like Covid-19. This can, with or without testing, limit the spread of the virus.
Surveillance systems have yielded mixed results across the country. While some states like Maharashtra and Kerala have identified and reported the maximum number of cases, others have delayed their response. Monitoring and quarantine is a function of a good surveillance system. The national Covid-19 task force that reviews containment measures on a daily basis should encourage states to be more proactive.
Despite India’s weak health care system, we hope to prevent the globe from exploding due to the proactive steps the government has taken so far. However, some areas still require improvement. While most experts request intensive testing, we should not wait until the test results are available.
We must immediately implement complementary detection methods, such as the syndromic approach, to identify and isolate the most probable cases. We are a country with software skills, and that should help us launch and scale mobile apps to track cases and their contacts, and map them.
Providing personal protective equipment and supporting the psychological well-being of health workers is a determining factor in addressing this. The Prime Minister needs to personally review these measures to raise and maintain the morale of front-line health workers. Implementing mass screening for cough and fever using thermal temperature scanners or automated phone / app-based reporting will help expand containment measures.
The crisis allows us to increase the capacity of critical care beds and improve supplies and logistics. Although the government has allocated Rs 15,000 crore to address these issues, we need additional appropriations to incentivize and recruit health professionals. Finally, measures must be taken on a war footing to disinfect carriers, streets and manage hazardous waste.
We are facing a complex challenge that requires innovation and perseverance. But we are at our best when we are challenged. Covid-19 has challenged India’s resolve and ability. While some of the experts predict a catastrophic end to the crisis, others think that flattening the curve is an urban myth. The efforts of number calculators matter, but as epidemiologists, our work requires us to offer solutions, not just numbers.
We are interested in understanding herd immunity, in which an infection provides immunity for large groups of people. The virus is smart, but we are smarter and younger. Population dynamics do not admit major victims in India, since the average age of India is 20 years, with only 8% of Indians 60 years or older. If we believe that some of the recent reports suggest that the virus cannot flourish at high temperatures, the rising sun in the coming summer is good news. This, however, does not exempt us from the responsibility of strengthening public health surveillance. The virus will not go away and many more may appear. It is time for us to use the force of epidemiology to make public health decisions.
Giridhara R Babu is a professor and director of epidemiology for life at PHFI, Bengaluru. Tarun Bhatnagar is a scientist at ICMR-NIE, Chennai
The opinions expressed are personal.