On April 27, different news outlets, including some of the leading newspapers in the country, quoted Singapore University of Technology and Design's (SUTD) Data-Driven Innovation Lab claiming 97.0 per cent of COVID-19 cases may end by May 19, and by 99.0 per cent by May 30 in Bangladesh. Ironically, this news spread across social media virally, the same way COVID-19 is spreading across the world! However, to anyone with basic knowledge of epidemiology and data science can verify that this research is far from scientifically sound. Having been a part of a group of experts who are trying model out covid-19 spread, here are some important things to understand:
1. The model used by SUTD is a toy model. If policymakers in Bangladesh somehow take wrong idea from this, the outcome could be catastrophic.
2. As everyone is waiting eagerly for good news during this pandemic, it is not wonder that such good news would go viral, but this brings the question of how ethical it is to share such a pre-publication research with no peer review
3. While the spread rate of COVID-19 slowed down in Bangladesh due to the lockdown, Bangladesh is far from eradicating it
TOY MODELS: Human interaction is the main vehicle of spreading COVID-19. As a result, for every country so far we have seen two states. Before lockdown: when everyone is moving freely and the virus is spreading at an alarming rate. During lockdown: when people are not moving much and the spread rate is slower as a result. The biggest issue with the Singaporean model is that it has no way to account for the change and the difference between these two states, as it is trying to fit a single equation for both cases. Naturally, as it is trying to explain both situations with a single equation, it can appear that the virus has slowed down, but the reality is that we have just entered to a lockdown state from normal pre-lockdown state. Now without proper measures taken, if Bangladesh opens up the country pre-maturely, there may be a return to the previous situation and this model cannot account for that.
Separately, in the long run the only way for a country to fully get rid of COVID-19 is either getting to a state when a majority of the population achieves immunity. That can be achieved when either the population know exactly what the virus is e.g. chicken pox or when scientists can find a vaccine and vaccinate everyone e.g. polio. The main concern has been that if Bangladesh takes out the lockdown too early, there could be a catastrophic second wave.
For example, in the graph-1 it can be seen that during the 1918 pandemic, more people died during the second wave of the pandemic, in fact, five times more people died during the second phase of pandemic. Using the toy model of Singapore, it is impossible to model the second wave. As a result, by using such mathematical models, it is not surprising that we would end up with some unscientific results.
ARE SUCH RESEARCH WORKS UNETHICAL: On the website of the Singaporean research (https://ddi.sutd.edu.sg/when-will-covid-19-end), it mentioned clearly that the model was created "STRICTLY ONLY for educational and research purposes" and that this will not be able to predict the scenario of each countries perfectly. They urge the reader to judge the results and to take this with caution. They also mentioned that over optimism based on these numbers is outright dangerous.
All that said, during these crazy times, when everyone is confused and when the majority of the consumers of the news have no scientific background to judge, it seems unethical to publish such results. In addition, digging slightly deeper, it is clear that this research uses the SIR model, which is an extremely simple pandemic prediction model from 1927. This model fails to take into account the differences in population and their behavior around the country. Not only that, just looking at their published graphs it is clear they tried to fit the results to a single curve without taking into account any of the aforementioned epidemiological considerations. Such research work is not only dangerous, but also unethical at this time.
REALITY IN BANGLADESH: Finally, in Bangladesh the number of tests per one lakh people is one of the lowest around the world. We have so far tested only 38.4 per one lakh of our population, whereas the number is two to three thousand in developed countries. Even disregarding the developed countries, our testing is lacking compared to countries such as India (61 per lakh) or even Pakistan (79.5 per lakh).
The key metric to understand any infectious disease is the so called R0 number, which signifies how many people get the disease from a single infected person. This is the basic reproduction rate, R0 of the disease. Through research it can be found that in Bangladesh it started with an R0 higher than 3.0 and the government has been able to bring it down to 1.1 with their interventions starting in late March. However, before it can be kept under the number strictly below 1.0, it cannot be seen that Bangladesh will end COVID-19 crisis. Especially, if Bangladesh opens up the whole country without ensuring proper social distancing and health care measures, a second wave is very likely. While Bangladeshi people can always hope, the hope is not a strategy when there is a pandemic at hand. There is basically no room for open up without proper coordination and consideration. Early opens up may push the country to go down the slippery slope of exponential growth of new cases rapidly.
To sum up, if Bangladesh cannot follow the footsteps of South Korea or Vietnam and do hundreds of thousands of tests daily, it will not be proven that we truly are not seeing a surge in COVID-19 cases. Policymakers and people have to take the right measures and unite for this cause to avoid a possible devastating second wave after May.
Tarik Adnan Moon (Harvard '15), Nur Muhammad Shafiullah (MIT '19), Adib Hasan (MIT '21), Sanzeed Anwar (MIT '20).