Winter months are looked upon favourably in Bangladesh. Many people wait all year for the months between November and February. But as this article is being written, there are reasons to approach the winter of 2020 with a healthy dose of apprehension and watchfulness. 

From the early months of the Covid-19 pandemic, scientists and researchers, medical practitioners, and even politicians and general observers have kept a close eye on the trend of the disease. While so much discussion has centred around regional and country-level trends of the disease and the first- and the second-waves of the disease, the world as a whole is doing no better today in stopping the spread of the disease than it was doing at the beginning of this year. In fact, the day-on-day increase in the number of new cases of the disease has sped up noticeably since the beginning of October.

Bangladesh government may not go for re-imposing shutdown leaving citizens more vulnerable to Covid-19 during winter. Photo: Reuters.

Let this, first and foremost, act as a sobering reminder of just where we stand in our fight against the pandemic and how much still remains to be done.

An argument against alarmism may be that mortality rates from the disease have gone down. However, this is because better treatments - both pharmacological and non-pharmacological interventions - for patients have been developed in recent months. Without a proper scientific understanding about the long-term implications of contracting this disease, globally rising infection numbers is a worrying phenomenon.

Another argument may be that at least Bangladesh (and neighbouring India and Pakistan), for example, is doing well, with a falling trend of daily new Covid-19 cases. However, it is possible that this seemingly improving Covid-19 situation is lulling us into a false sense of security.

To wit, a look at the global scenario should act a stern reminder of what may still lay ahead for us.

A look around the world

By mid-March, Europe had become the epicentre of the pandemic. Countries such as France, Germany, Italy, Spain, and the United Kingdom saw a rapid growth in the number of daily cases of Covid-19 patients. Most of these countries experienced the peak-daily caseload from their "first-wave" of the pandemic sometime in the late-March or early-April. Following this peak, caseloads started to ease off and by June 2020, most of the European countries appeared to have successfully restricted the spread of the disease.

During the same period, the situation in the Southern Hemisphere was very different. Daily caseloads were relatively low in the early months. Numerous theories proliferated as to why this might have been: European countries, being more cosmopolitan, had the busiest airports and the large number of people leaving and entering these countries had led to greater spread of the disease within their borders; Africa's recent experience with Ebola and South-east Asia's experience with bird-flu meant that these countries were better prepared to deal with pandemics; population of developing countries tend to have stronger immune systems; Europe has an aging population, which makes them more susceptible to diseases; et cetera.

However, as things calmed down in Europe, caseloads skyrocketed in the South. The July-August period was characterised by the peak of the pandemic in South America and Africa and many observers interpreted this as the pandemic finally catching up with the rest of the world.

However, from around the end of August and beginning of September, the trend reversed again. The Southern countries started to experience a fall in their daily caseload and the Northern countries, who had seemingly "won" the fight against Covid-19, started to experience a sharp rise in their daily caseload.

This second-wave, in all countries, is proving to be more virulent than the first-wave.

Is this simply a case of the southern countries finally developing their health-sector sufficiently and implementing policies that brings the pandemic under control, while many European countries re-opening their economies after months of restriction are observing a resurgence of the pandemic? Or is there a better, over-arching explanation for all these?

Covid-19 and seasonality

One of the reasons for this globally-heterogeneous and regionally-homogenous trend of Covid-19 cases may be the fact that weather pattern of a region plays a strong role in the spread of the disease. There is sufficient epidemiological and biological evidence of increased human susceptibility in cold weather to viral pathogens similar to Covid-19, such as Influenza, SARS, and MERS.

Winter in the Northern Hemisphere is during the early- and late-months of the Gregorian calendar (October-March). Winter in the Southern Hemisphere is during the middle-months of the Gregorian calendar (April-September). Seen through this prism, each region, and country, seems to have experienced the peak of the pandemic during their winter months.

Winter, in Bangladesh, is not far away.

What this means for Bangladesh

Weather patterns are an important determinant of the rate of spread of Covid-19, but it is not the only determinant. The fact that the United States of American is going through its third-wave right now is a result of political-wrangling more than anything else. South-Pacific countries not experiencing swings in caseloads due to changes in weather is mostly down to effective implementation of Covid-19 prevention strategies. Similarly, declining temperatures notwithstanding, the current and upcoming lockdowns in European countries will go a long way in curbing the spread of the disease.

However, examples from around the world also show that re-imposing lockdowns are often met with low compliance from the citizenry. It is likely that the Bangladesh government will not want to go down that route. But then how should we, the people, react to what is coming our way this winter?

The first solution is to help yourself by being personally responsible for your well-being and for those around you. This can be done by working from home if that option is available to you; by getting your groceries delivered to you; by always wearing masks and maintaining social-distancing whenever possible; and by not going on capricious vacations to Cox's Bazar.

The second solution is to help your community by proactively spreading the word that now is not the time to let our guards down. In a 24-hour news-cycle, there is a surprising news-vacuum about the link between the spread of Covid-19 and weather-patterns. We have to try and rectify that.

Ahsan Senan, Lecturer of Economics, Brac University.