'We need to vaccinate at least 70% of the population'

'There is a Covid vaccine-mania that is happening in the world now and the vaccine makers are using this mania for their own gains.'

Dr Ishwar Gilada is an expert on HIV care and infectious diseases who set up India's first AIDS clinic in 1986 in Mumbai.

"It's just impossible to vaccinate all," Dr Gilada tells Shobha Warrier/Rediff.com.

There is a race for vaccine happening all over the world. The UK has begun vaccinating its citizens. Will we be able to vaccinate the whole world?

There is a Covid vaccine-mania that is happening in the world now and the vaccine makers are using this mania for their own gains.

Take, for example, the vaccine for Hepatitis B. It is so cheap, just Rs 200 or so for three doses and you are immunised for your entire life, but a minuscule, less than 10%, are immunised.

In the case of the Covid vaccine, you take two doses and the immunity is only for a year!

The governments have to decide who to vaccinate first and in which order they should do so.

It's just impossible to vaccinate all. We could give the polio vaccine to 90% of the children as it is an oral vaccine and could be done by the Anganwadi and ASHA workers, and that too it took several years. This is different.

Will it be alright if we vaccinate just 50% of the population?

I don't think that would help. We need to vaccinate at least 70% of the population.

Next is, it depends on the efficacy of the vaccine. If the efficacy of a vaccine is 50%-60% and if you are immunising 50% the population, in effect only 25-30% of the population gets immunity.

But if the efficacy of the vaccine is 90% and if you can vaccinate 70% of the population, it might help. Add to this those already infected and have their own immunity.

Pfizer claims 95% efficacy, Moderna also claims 95%, but Oxford says only 70% with the first dose and 90% after the full dose...

First of all, these are research organisations and what they should have done is, publish the results in a reputed peer-reviewed scientific journal and not give press releases.

On the first day, Pfizer said their vaccine was 90% successful. The next day, Moderna said their vaccine was 94.5% successful. To counter this, Pfizer said, the efficacy of their vaccine was actually 95%. It clearly shows they only want to score brownie points!

Then Oxford said if you gave half the dose the first time, the efficacy was 90% and if you gave full dose first time, it was 60%.

But then why do you give half dose in the first time, when your study protocol did not mention that? Why didn't they give half dose the second time also, by getting the protocol modified and adding one more arm to the study? 

What I can see from these claims is not an actual scientific outcome, but a kind of mania!

This should not be allowed at all in the scientific arena.

Now, one volunteer alleged that he had severe side effects. Will it have an impact on the rest of the trial and outcome?

Usually vaccines are neither started or stopped on public outcry. The creation of a vaccine is based on a certain criterion and its final outcome.

Nothing about the vaccine trials should be there in the public domain; only after you get the results, should the public know.

One person complaining against the vaccine will not affect the progress of the vaccine as we have to look at the progress of the vaccine from the perspective of a larger public interest.

Russia's Sputnik V was the first Covid vaccine to come out, but it appears the world does not trust it. Is it because they did not do the phase 3 trial, and everything about the vaccine is shrouded in secrecy?

Yes, Russia and China were the first countries to come out with licensing the Covid vaccines. But both of them did not do phase 3 trials. And the first two trials were done on those who work in the military.

Trials done on military personnel is not considered authentic by the world.

Phase 1 is a safety trial done on 30-40 people while phase 2 is an immunogenicity or efficacy trial done on 300-500 people. But phase 3 is done on 3000-5000 or even 50,000 people to find out both safety and efficacy of the vaccine in larger population. That too it is double-blind, means half the volunteers get the candidate vaccine and other half get a placebo.

It is allowed to give licensing to vaccines in case there is an emergency situation. So Russia and China have given emergency authorisation, but that is restricted to their own countries. If they want to sell Sputnik V to any other country, for example, they will get permission only after they do a phase 3 trial in that particular country.

Now, Sputnik V is going to be manufactured in India.

But the Government of India has not given the licence to market in India. They can do that only after they do phase 2B and phase 3 trials here. The phase 2B is needed because the Indian population is genetically different from the Russians.

But they can go ahead with phase 2B and phase 3 simultaneously, and it is not necessary to wait for the results of phase 2B trial before starting phase 3.

In fact, Oxford is also doing phase 2B and phase 3 trials in India. Out of the 1600 volunteers, 400 are going through phase 2B and 1200, phase 3.

Though both the trials are done simultaneously, they will get the licence only after knowing the outcome of the phase 3 trial.

we see vaccine nationalism. rich countries have pre-booked vaccines for their citizens. Does that mean no vaccine for the poor countries?

It is the survival of the richest and the fittest!

In fact, America has pre-booked six times more doses than what they need!

The worst affected are also the rich countries...

For that, I give credit to the Covid virus! It has shown that nobody is bigger in front of the virus.

If most of the vaccine produced is taken by these countries, what will happen to the developing and under-developed countries? Yes, India is developing its own vaccine and most of the vaccines are going to be manufactured in India.

Currently, most of the world, particularly the developing world, depends on India for healthcare, especially for medicines and vaccines.

Do you know 80% of anti-retroviral therapy used in HIV treatment globally is manufactured in India? Today, Africa is remaining intact only because of India. Otherwise, people would have died like ants because of HIV and other related illnesses in Africa. It is because India made the HIV medicine available at 1% of the international cost

When it was available at $10,452 per patient per year internationally, we made it available for $69, almost at 0.65% on global cost. Not just ART, India has been supplying many other drugs to Africa. We proved to the world that though we make medicines at a cheaper rate, they are as effective.

In the end, we are able to save millions of lives.

Similarly, 60% of all the vaccines used globally are going from India.

In the case of Covid vaccine also, like what (Adar) Poonawalla said, they would give 50% of the vaccines to India and the rest of the 50% to WHO's GAVI -- the Global Alliance for Vaccines and Immunisations. From there, it will go to the poor countries. That's how the poorer countries will get the vaccine.

If they are left to the mercy of the Europeans or Americans, they will die.

• Part 2: 'Covid virus is getting weaker'

• War Against Coronavirus