Explainer: Advantages, side effects, here's all you need to know about Covid-19 nasal vaccine

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As the Union Health Ministry has given approval to Bharat Biotech's needle-free intranasal Covid vaccine as a booster dose for those above 18 years of age, the doctors in the city are now receiving queries about the vaccine.

On Tuesday, the Centre approved the cost of Bharat Biotech's nasal COVID-19 vaccine iNCOVACC at Rs 800 for private hospitals and Rs 325 for government ones. The vaccine will be rolled out in the fourth week of January.

The iNCOVACC nasal vaccine is already been listed on the Co-WIN portal by the government and the vaccine will soon be available at private vaccination centres. Health experts have responded to a few queries of the general public:

Are nasal vaccines better than conventional vaccine shots?

While many people are in doubt that they can mix and match different vaccines, according to health experts, there is no proven benefit. According to a Mumbai-based doctor, physiologically nasal vaccines have a theoretical benefit over conventional vaccination. However, they have not been convincingly proven to be more beneficial than conventional vaccines.

What are the benefits or advantages of a nasal vaccine?
Nasal vaccines have several advantages. They do not require injections, so there is no pain and need for trained personnel.

Explaining the advantages, Dr Sanjith Saseedharan, Consultant and Head-Critical Care, SL Raheja Hospital, Mahim said, "Nasal vaccines are considered mucosal vaccines, which means they stimulate the immune system at the site where the vaccine is administered. This can lead to the production of local antibodies at the site of application, as well as the production of antibodies throughout the body. This local immune response may halt the spread of the illness or help prevent the virus from entering the body."

The production process for these vaccines is also simpler, which makes it easier to produce and deliver to the population.

Is it a good idea to mix and match different Covid vaccines?

"What is clear is that when vaccines are used from different platforms then the immunity gained also called ‘heterologous immunity' is better than the homologous or same vaccine usage. However, the clinical effectiveness of any form of protocol still lies in the fact that both would prevent a severe illness when it comes to Covid-19," explained Dr Saseedharan.

Also read: Covid-19: People now reluctant to undergo RT-PCR tests

Who is eligible for nasal vaccine?

"As far as nasal vaccines are concerned, those people who have already taken a booster vaccine or booster dose can take a nasal vaccine as a precautionary dose," Dr Manish Pendse, Senior Consultant Physician, Medicover Hospitals said.

Who shouldn't opt for a nasal vaccine?

At the moment, pregnant women and individuals less than 18 years should not receive the nasal vaccine as there is no data available on its safety and effectiveness in these subgroups.

Dr Saseedharan explained, "Individuals who have hypersensitivity to any of the ingredients in the vaccine (such as Sodium Chloride, Magnesium Chloride, Glycerol, or Polysorbate) should also not receive the vaccine. It may not be advisable for people with a history of severe allergic reactions to vaccines or injectable medications, as well as individuals with allergies to food, pet dander, venom, or latex."

He added, "Those with current infections or fever should also avoid the vaccine. There is no information available on the effectiveness of the nasal vaccine in immunocompromised individuals, including HIV and transplant recipients on immunosuppression."

What are the side effects of iNCOVACC?

As per the factsheet shared by Bharat Biotech, side effects that have been reported include headache, fever, running nose, and sneezing. It also mentions ‘A severe allergic reaction may very rarely occur after getting a dose of iNCOVACC, however, no such event was reported in the clinical trial.'

Can a person who has already taken a booster dose, also opt for a nasal vaccine as another precautionary dose?

"There is no scientific information yet available on the appropriateness of the use of a nasal vaccine in such a situation," mentioned the doctor.

Are there demands for nasal vaccines at the hospital's vaccination centre?

Yes, patients are enquiring about these vaccines and this is mostly due to the theoretical benefits and the absence of injection.

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Queries/doubts about the nasal vaccine asked by the public so far

Speaking about the queries asked by the general public, Dr Saseedharan said, "The doubts were around the rationale of whether the nasal vaccine will give them Covid-19. There are concerns about the effectiveness of the vaccine due to the lack of data available in the public domain on its efficacy and side effects through this unconventional method of vaccination."

He further added, "A significant portion of the population is inquiring about whether this vaccine can be given as a booster dose after receiving either Covishield or Covaxin."

Does vaccine hesitancy still exist in public?

According to the doctors, the level of vaccine hesitancy has reduced in the general public.

Dr Manish Pendse said, "In the first phase of the vaccination drive, there were a lot of queries from the patients but as time went by, and probably to some extent, the government also made it mandatory for travel purposes, so people have been very proactive in taking the vaccination. Now, the doubts and hesitancy are slightly less."

He added, "One problem which we faced during the vaccination drive was about general allergies to patients. But eventually, you know, even those people have been given the vaccine."