Decoding the COVID ‘waves’ and when they will stop

Dr Shuchin Bajaj, Founder and Director, Ujala Cygnus Group of Hospitals analyses the interrelation between pollution, colder temperature and COVID-19 to understand the reason behind the waves and suggests long and short terms measures to manage the COVID-19 pandemic

At the start of the untimely winter this year, COVID-19 cases in Delhi-NCR spiked drastically and caused a number of deaths. The number of affected people in the national capital Delhi was 5,97,112 and more than 52,000 people have been affected in Gurgaon. While some termed it as a ‘third wave’, some experts have predicted that the situation could worsen around February or March next year. Before we start worrying, it is important to understand the interrelation between pollution, colder temperature and COVID-19 to understand the reason behind the waves and whether they will subside.

Understanding the unholy trinity

It is important to understand what makes the virus rampage in bouts and not continuously. Coupled with pollution and cold temperatures, COVID-19 virus has been spreading fast, especially in urban areas. The disaster is primarily driven by pollutants such as PM 2.5 and PM 10 that have multiple health ramifications.

One study, identifying threshold levels of PM2.5 and PM10 connected to COVID-19 as per the city’s population density, highlights that the Italian city of Milan recorded PM10 values above it and establishes a positive correlation between the PM concentration and the number of deaths in March. The research states that high concentrations of PM during February could have increased the spread of the virus in Milan more than in other Italian cities and atmospheric particulate matter may have played a carrier role in COVID-19.

Now, let us understand how this happens. Continuous exposure to fine particle pollutants such as PM 2.5 and PM 10 causes severe inflammation of lung tissue, involving the angiotensin II converting enzyme (ACE-2), an enzyme that is also the key receptor through which the COVID-19 enters human cells. This inflammation weakens the lungs, affects its capacity to absorb oxygen (determining oxygen saturation level in our body), and in turn, becomes unable to sustain the viral onslaught.

While these pollutants get a larger area to spread during hot weather, when the atmospheric temperature starts dropping, the air becomes heavy and the pollutants get trapped at a level closer to the ground. This makes the impact more lethal and widespread. In times of a pandemic, caused by a virus like COVID-19, this can only translate into more number of people getting infected. Colder temperature is worse for people with chronic lung disease and other chronic diseases as they are more vulnerable to community-acquired infections. Pollution only adds to the plight.

When will COVID waves stop

As much as we can gather till date, COVID-19 virus is unlikely to disappear in thin air. Rather, as vaccines help people develop immunity and achieve ‘herd immunity’, it is likely that COVID-19 will become another form of flu. So, similar to the flu vaccines that one must take every year, we may continue to fight COVID-19 similarly. However, if we are not able to control pollutants like PM 2.5 and PM 10, diseases like COVID-19 will continue to lay siege on us. Therefore, in order to fight outbreaks like the COVID-19 pandemic, the governments must collaborate and resolve to phase out fossil fuel, the only way to contain pollution and the virus.

The other aspect is more immediate. If we analyse how the pandemic has behaved across the world, we will find natural variables such as temperature being less effective parameters than human behaviour. Countries which have been able to implement public health guidelines of wearing a mask, maintaining hand hygiene and a distance of six feet between two people have done well in managing the spread of COVID-19 virus. Therefore, governments must ensure that a continuous message is being disseminated among people to carry out these measures.