‘Adverse event surveillance is being set up in health facilities across the country’

Regulators are not taking any shortcuts on ensuring safety of COVID-19 vaccine, says NTF member N.K. Arora.

January 11, 2021 07:26 pm | Updated November 30, 2021 06:41 pm IST

N.K. Arora

N.K. Arora

Dr N.K. Arora, executive director of the New Delhi-based INCLEN Trust and head of the operations research group of the ICMR’s National Task Force for COVID-19 says all safety related information will be shared with the public as it emerges with the use of COVID-19 vaccine.

This is for the first time the government is going to vaccinate adults. Does it require any special preparation?

Yes, it does. India has an existing vaccine safety surveillance mechanism called the AEFI (Adverse Events Following Immunisation) surveillance. It’s comprised of a national secretariat under the Universal Immunisation Programme (UIP), including doctors, data specialists and public health specialists. The vaccine safety surveillance network extends up to every district where a panel of doctors and health workers monitor events of concern after getting any vaccine, investigate and report to State and national level.


COVID-19 has necessitated immunisation of the adult population. The government has now involved cardiologists, neurologists, general physicians and pulmonologists in AEFI committees at national, State, and district level.

Right now, we are anticipating — theoretically — events of concern that might possibly happen after immunisation drive. The AEFI members will be trained to look for any adverse events before we start the immunisation process. Adverse event surveillance is being established to actively seek these events across designated health facilities across the country. Additionally, there are around 300 medical colleges and tertiary care hospitals across the country that have adverse drug reaction monitoring centres which also report adverse events after vaccines along with drugs.

What kind of awareness programmes do we need before rolling out the immunisation for COVID?

We need to educate people and make them aware of lesser-known facts about vaccines. For example, some people might face mild symptom such as pain or swelling, mild fever, among others. It is a normal immune response.


Then, it is important for people to know that vulnerable population — the elderly, people with associated illness, such as diabetes, chronic lung disease, high blood pressure, kidney ailments, cancers and others may, otherwise also, suffer from any sudden health issues such as heart attack. We cannot and should not link it to the vaccine in all cases. I believe that we need to practise ‘exceptional transparency’ in this case. I assure that all safety related information will be shared with the general population as it emerges with the use of COVID-19 vaccine(s) either in our country or in any other part of the globe with the same vaccine.

Indian regulators gave authorisation to Covaxin even before its phase-III trial results were out. How do we explain this?

We are passing through troubled times. COVID-19 has caused social disruption, economic downturn and significant number of deaths. To control this pandemic, the society as well as the system may have to take steps which may also be termed as drastic. Both pre-clinical and clinical data (complete data for Phase I and II, and partial data for Phase III) of Covaxin have been thoroughly scrutinised by the regulators. This data shows that the vaccine is safe and induces a robust antibody response. However, to what extent the vaccine will protect the recipients from getting the disease is not known yet. Therefore, the regulators have allowed its use in trial mode.

What would trial mode mean for a vaccine recipient?

The way we do in a clinical trial phase: First, the recipient will be asked to give a written consent. Then he/she will undergo some blood tests before and after taking the vaccine. Additionally, the recipient will be followed-up actively to see if the vaccine has led to any side effects. In short, it will be an extension of the Phase-III trial. But in this, the person would know that s/he has received the vaccine, and not the placebo. It will be completely a person’s choice if he/she would like to give the vaccine a try or not.

Developing a vaccine takes years. But this time our scientists have developed a vaccine against coronavirus in such a short time. How was this possible?

Developing a vaccine generally involves years of research. First, we need a vaccine candidate that is evaluated in animals for its safety and efficacy. After a vaccine candidate passes a pre-clinical trial, it enters the clinical trial phase. While scientists have worked round the clock in the laboratory, even regulatory approvals which used to take several months have been pretty quick. It helped eliminate all the time lapses between the pre-clinical and clinical trial stages. Earlier, the vaccine development involved a series of steps, but in the case of the coronavirus vaccine, the scientists and regulators worked in tandem, accelerating the whole process without compromises on any protocols and any step.

What is your opinion on the safety and efficacy of the vaccine?

To ensure that a vaccine is safe, we need to try it on a large number of people. The vaccine developers have not reduced the sample size at any stage of clinical trials rather it was bigger than what we usually test a vaccine on.


When a vaccine is tested, most of the adverse events or unwanted effects, if any, occur in the first four to six weeks of its administration. So, in order to ensure that it is safe, we keep a close watch, for the first two-three months, on the people it has been given to. This data helps us decide if a vaccine is safe. All concerned in the line of vaccine development, testing and evaluation have followed these procedures to the tee. Both Indian vaccines are considered safe on this yardstick.

As for the efficacy of the vaccine, we need time to tell how effective a vaccine is. All the global agencies have set the benchmark that only those vaccine candidates which show the efficacy of at least 50-60% will be considered. Interestingly, most of the vaccines have shown the efficacy of 70–90% within the short period of 2-3 months of observation, way more than what we were expecting. Besides, when a vaccine is given an emergency use authorisation, as in case of COVID-19 vaccine, the trial follow-ups continue for one-two years to assess the total duration of protection the vaccine will provide.

What is emergency use authorisation. Does it involve any short-cuts on the part of our regulators?

Not at all. In fact, our regulators are taking extra precautions. Some vaccine candidates were not considered for review by our regulators as the data was inadequate; some companies were asked to increase their sample size so that our regulators can have adequate evidence to support the safety and efficacy of the vaccine before they approve it.

Similarly, Indian regulators wanted the U.K.’s regulator to approve Oxford’s vaccine first before even considering it for the Indian population. An important pre-requisite of the COVID-19 vaccine authorisation for our country is – the vaccine should have been evaluated on subjects in India. The regulators are not taking any shortcuts when it comes to ensuring the safety of COVID-19 vaccines.

Top News Today

Sign in to unlock member-only benefits!
  • Access 10 free stories every month
  • Save stories to read later
  • Access to comment on every story
  • Sign-up/manage your newsletter subscriptions with a single click
  • Get notified by email for early access to discounts & offers on our products
Sign in


Comments have to be in English, and in full sentences. They cannot be abusive or personal. Please abide by our community guidelines for posting your comments.

We have migrated to a new commenting platform. If you are already a registered user of The Hindu and logged in, you may continue to engage with our articles. If you do not have an account please register and login to post comments. Users can access their older comments by logging into their accounts on Vuukle.