A year after the Coronavirus pandemic wrecked our collective lives, our society has been grappling with fear and insecurity. As a result, we have seen misinformation spread like wildfire, and many resorting to bizarre and incorrect methods of dealing with the virus. With this column, which will be published every Sunday, we aim to address any health or vaccine-related question our readers might have about the coronavirus pandemic.
In this week's column, the queries have been answered by Dr Arun Sharma, Professor, Community Medicine, University College of Medical Sciences and GTB Hospital, New Delhi. Sharma's answers address how vaccines work, and how can the poor and marginalized access them.
Q: The registration process for the vaccine until now is to self-register in the Co-WIN app. However, how can those elderlies from low-income families register, who do not have access to mobile or internet?
A: The government has pre-registered around one crore healthcare workers for the vaccination in the first round which is currently ongoing. Apart from self-registration on the Co-WIN mobile app and website, the government is organizing registration camps across the country, where those who don't have access to mobile or internet can get registered.
Q: How does the vaccine work? Why do both the vaccines (Covishield and Covaxin) available in India have two doses, 28 days apart?
A: Vaccines stimulate the body's natural defence mechanism by producing antibodies against the virus. It recognizes the disease-causing pathogen and produces antibodies to fight it. In the process, it develops a memory for the disease and how to fight it.
Most COVID-19 vaccines are being given in two doses. It is only about 14 days after the second dose that a person develops adequate immunity against the virus. In the case of Covishield and Covaxin, the two doses can be given at an interval of 4-12 weeks. Since it is a pandemic situation and the government wants to cover the maximum number of people in the shortest possible time, the two doses are given 28 days, or four weeks, apart.
Q: How many people have to be vaccinated to reach herd immunity in India?
A: There are two ways to acquire herd immunity—one, on exposure to the pathogen people develop antibodies/ immune response in the body, and second, the body develops antibodies/ immune response when we give the vaccine. The actual percentage is unknown; it is popularly believed that 60-70 per cent of the population should develop immunity against pathogens to reach herd immunity.
Q: How effective are the two vaccines that are being rolled out in India on the new strain of COVID-19? Is there any scientific evidence to prove that they would work against the new variant?
A: Viruses keep mutating. Some mutations make the vaccine ineffective. As of now, the vaccine is considered effective against the new strains that originated in the United Kingdom and South Africa. It depends on multiple factors, for example, the types of mutations, and the technique with which a vaccine has been developed. The inactivated whole virion used in the development of Covaxin is expected to achieve a wider antigenic presentation to our immune system resulting in a versatile spectrum of immunity. Covishield also has been found to be effective against the reported mutant variant.
Q: Will the vaccine be available for purchase in private hospitals? If so, how will the government standardize the rates?
A: In the first phase, since there is a gap between the demand and the supply of the vaccines, the government has decided to give vaccines to prioritized groups. These groups have been formed to protect those who are most susceptible to catching the infection and those who are more vulnerable to developing severe disease. At present, the vaccines are being given under emergency use authorization. Eventually, the vaccine will be available in the market for purchase after the license is granted for it by the competent authority.
Q: Does the vaccine interfere with any other regular medications?
A: The vaccine has not been found to interfere with any regular medication.
Q: Will masks and other precautionary measures become redundant after the vaccination process? If not, why?
A: No, masks will remain relevant even after the vaccination. In fact, one is advised to follow all COVID-appropriate behaviour till the time we vaccinate a good number of people across the country. It is only after the 14 days of taking the second dose of the vaccine that the body will develop an adequate amount of antibodies to protect you from developing severe disease. You may still get the infection and spread it to your near and dear ones. So, continue wearing the masks, maintain social distance and follow hand hygiene.
Do you have questions about Coronavirus? Or the vaccines? Send us your questions: Tweet with #AskADoctor. Every week, we will have a public health expert to address your concerns through this column.