While scientists the world over are trying their best to develop a vaccine and an anti-viral for Covid-19, governments are looking to arrest the rapid decline in the global economy by lifting the lockdown in phases.
In such a scenario, in which the number of Covid-19 cases has been rising unabated, and suitable preventive and therapeutic solutions to the pandemic are yet to be discovered, a second wave of the infectious disease could turn out to be a nightmare.
First, what is the second wave of Covid-19?
By now, you must be aware that pandemics are caused by pathogens such as viruses and bacteria. And since these are new, the human body invariably has no immunity against them.
Also, pandemics are uncommon but influenza, or a viral infection that attacks your respiratory system, is one of the more frequent causes.
One of the most common features in many of the pandemics that we have had in the recent past is influenza-like symptoms in which the viral infection attacks the respiratory system.
Now the novel variant of a flu virus that has acquired pandemic proportions wreaks a great deal of havoc before retreating temporarily due to factors like changing weather conditions or an extraordinary curb on movement induced by lockdowns that aim to contain the spread of the virus.
However, once there is a another change in the weather or the lockdown is lifted fully or in phases, it can start spreading around the world again.
According to scientists, the trajectory of Covid-19 cases in India may have plateaued and could even fall for some weeks after the lockdown is lifted. However, the country is likely to see a second wave in late July or August, with a surge in the number of cases during the monsoon.
The timing of the peak will depend on India's ability to sustain social distancing and the extent to which the infection spreads once the restrictions are relaxed, they said.
But why exactly is the second wave being made out to be such a big deal?
Last month, China reimposed restrictions in certain parts of the country because of a wave of new cases, indicating that a second wave is in the offing.
Countries are rigorously practising social distancing and have announced lockdowns to contain the further spread of the virus. However, once the lockdown is lifted, it will leave many people vulnerable to infection as they begin to venture out again. This is because the virus was only contained, and not treated.
Sundaresan, corresponding author of a working paper by researchers at IISc and the Tata Institute of Fundamental Research (TIFR) in Mumbai, confirmed this in an interview with PTI. He said, "Once we return to normal activity levels, there is a chance that the infection may begin to rise again. China is seeing this to some extent post easing of some restrictions on travel.”
While there are many reasons including changing weather conditions and movement restrictions that cause the phasingout of the first wave of infection, we should not forget that the second wave of the historic influenza outbreak in 1918 caused most of the deaths in the pandemic.
According to a media report, some researchers believe the second wave of the 1918 outbreak was brought about by a mutation that once again made the virus unrecognizable to most people’s immune systems. Another important variable is the movement of the virus to populations that haven’t been exposed before and don’t have immunity.
In fact, reports suggest that there are cases of people who have recovered from coronovirus being infected with the disease again. The fact that many of them asymptomatic, meaning that they aren't showing signs of extreme weakness, fever or difficulty in breathing, makes the scenario quite frightening.
Yet there is hope. A disease from the coronovirus family called severe acute respiratory syndrome, or SARS, infected parts of Asia during the 2002-2003 outbreak, but never acquired the stature of a pandemic.
So, what can we do?
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 "What is the second wave of Covid-19 and why should we be worried?")
