Facts regarding Covid-19
Dr Arvind Sahni, Gastroenterologist
Introduction
The latest name for this virus is SARS-CoV-2 (Severe Acute Respiratory Syndrome-Corona Virus 2). Currently, this virus is causing a pandemic. Up to 30 per cent of the cases may be asymptomatic but scientific evidence suggests that they have a significant transmission potential of disease. The transmission of this virus may occur early in course of infection.
Identification of chains of transmission and subsequent contact tracing are much more complicated if many infected people remain asymptomatic or mildly symptomatic. Thus one infected person has the potential to infect several thousand people within a short span of a few days.
It is these asymptomatic or mildly symptomatic infected people who may potentially infect their family members and the community at large. The infected patients who are sick, who need hospital care can spread the virus to health care workers.
Modes of transmission
The commonest mode of transmission is by droplet infection. These droplets could spread from an infected person to a distance of approximately 1 to 1.5 metres. This is the basis of social distancing.
To break the person-to-person transmission of this virus apart from doing social distancing, it is also important to have a complete lockdown strategy as is being done in our country.
When an infected person coughs, different size droplets (usually less than 10 microns) are expelled into the surrounding environment as an aerosol. Scientific experiments have suggested that this SARS-CoV-2 virus may persist for up to 3 hours in the aerosol. This virus can also persist on fomites like cardboard and stainless steel for 24 hours and on plastic for three days. Hence, the need to disinfect these fomites, which are also an important means of spreading the infection.
Spectrum of presentation
Approximately 80 per cent patients will have mild symptoms, 15 per cent develop pneumonia and 5 per cent will need ICU care.
Vulnerable population
Elderly people, diabetics, people with underlying heart, lung and kidney diseases and people with weak immune system. However no age is exempt.
Drugs and vaccines
The WHO has begun a trial regarding the efficacy on drugs against this virus. India is one of the countries that is participating in this global trial. The prospects of developing a vaccine on a mass scale are at least one to one and half years away. To reinforce the words of Dr David Nabarro, special envoy to the WHO on CoVID-19, “Respect the virus.”
Take home message
Let us all join hands to fight this global health emergency and pandemic. This is a highly infective virus. Practise social distancing and follow the complete lockdown instructions in an effort to break the human-to-human chain of transmission. Do not forget your basics of frequent hand washing with soap and water. Avoid touching your eyes, nose and face with your hands.