By Dr Edward Nazareth

Apr 12: As the number of new cases of COVID19 are exceeding a lakh per day and deaths from COVID19 are also steadily increasing, the Union Health Ministry of India has warned that Covid-19 is spreading at a faster rate in the country compared to last year. The authorities have cautioned not to take the ongoing pandemic lightly; however common people seem to be care free. Wearing a mask and wearing it properly, maintaining social distance and avoiding crowded places is hardly seen.

In India, COVID19 vaccines are available for everyone over the age of 45 years. This is the third phase of COVID19 vaccine drive in our country. More than 65 million doses have been given so far, mostly to frontline workers and people above the age of 60. The world's biggest inoculation drive aims to cover 250 million people by July this year.

But a good number of people are hesitant to take the jab. Refusing a vaccine when one is available is known as ‘vaccine hesitancy’. The vaccine hesitancy is a worldwide problem – the World Health Organization considers it as a global threat of health. Wrong information is a major cause of vaccine hesitancy, and there is much misinformation about both COVID-19 and its vaccine.

In the past few weeks, I have been getting calls from people who have read my earlier articles in Daijiword seeking clarification on taking COVID 19 vaccine. I have answered some of those questions in detail here, so that it may be of use to others.

Short lived side effects

• I am 65 years of age, retired from service. I have diabetes and blood pressure both are under control. I also take one aspirin per day as per the advice of my physician. I have read about the side effects of vaccination and it is the main reason I am hesitant to take it.

After the first phase of vaccination of health workers, the Government offered vaccination to people of your age with or without medical illnesses. It is because people of your age are at greater risk of getting severe illness if infected by COVID19 virus. Whatever precautions you take, you can get infected and it can be quite grave. At present vaccine is one of the best tools to avoid serious illness even if one is infected.

The side effects of vaccination are negligible compared to the illness from infection. The short-lived side effects like fatigue, headache, muscle aches and fever are seen in few people after vaccination and they are more common after the second dose. The people who experience unpleasant side effects after vaccination often describe feeling as if they have a bad flu. If one gets the side effects or anticipates them, medicine like paracetamol or ibuprofen may be used for a day or two after consulting their physician.

Vaccination: Social responsibility

• I am 45 years of age, hale and healthy. I don’t have any co-morbidity. I do regular exercise and take all precautions against infections. Even if I am infected by COVID19 virus, I will not become sick. Then, why should I take COVID 19 Vaccine?

As you know the second wave of infection by COVID19 virus is spreading fast. There is every possibility that you might get infected. You cannot be sure that you will not get the sickness if infected. Though the people with co-morbidities are more likely to become sick if infected, even those without any pre-existing disease can get serious illness because of COVID19 infection. The illness also depends on viral load and infection can lead to many complications. There are deaths reported in hale and healthy youngsters after COVID19 infection due to complications.

Second issue is if you get infected, you may not get the sickness but you can spread the virus to many people who may come in contact with you. You may not even know that you have the virus. Asymptomatic people can spread the virus to their kith and kin. If you have relatives who are elderly or sick, they can get the virus from you. You may, thus be a cause for their illness.

More than all this, we have to achieve ‘herd immunity’ to eradicate the menace of this virus. ‘Herd immunity’ means that majority of people become immune to the virus; they will not get sick or spread the disease to others. In this way, the whole community is protected. The proportion of people that need to be immunized to achieve herd immunity is different for different diseases. For COVID-19, experts estimate that between 70% and 90% of a community would need to be vaccinated against the virus to achieve herd immunity.The people can become immunized either by having a COVID-19 infection or through taking a vaccine.

As COVID-19 can be a very serious illness, if 70% to 90% people get infected, a large number of people would need to be hospitalized and many could die. Therefore, having a vaccine that works is so important. With a vaccine, many more people could become immunized without getting sick. If enough people do not take the vaccine, then achieving herd immunity becomes much more difficult. Being responsible citizens, it is our duty to get vaccinated so that we help our community to achieve ‘herd immunity’.

Vaccine and alcohol

• I am 50 years. I have sugar problem, but is under control with tablets, diet and exercises. I have the habit of taking two pegs of Whiskey daily before dinner. I am informed that total abstinence of 45 days is required after vaccination. This is the reason why I am hesitant to get the vaccine jab.

There are no effects on the efficacy of the vaccine or increased incidence of side effects of vaccination if one takes any type of alcohol before, between, or after the vaccine shots. There is currently no evidence that drinking alcohol interferes with the functioning of the Covid-19 vaccines.

Till date more than 570 million doses of various Covid-19 vaccines have been administered across 141 countries all over the world. Out of these vast numbers, there have been no reports yet of vaccine efficacy declining as a result of alcohol consumption. It is understood that alcohol does not impede the formation of antibodies.

Vaccine and clot formation

• My Dad, who is 76 now, had paralysis due to clot formation in the brain about two years ago. He has partially recovered, but he still has to use a cane to move around. He is diabetic and hypertensive. He is on medicines for these and also taking other medicines like blood thinners. There are reports that the vaccines cause blood clots. Because of this Dad is hesitant to get vaccine.

Recently, vaccinations with the AstraZeneca COVID-19 shot were put on hold in a few countries across Europe following reports of rare blood clots. However, the European Medicines Agency (EMA) and World Health Organization (WHO) have issued statements that the overall risk for clotting with this vaccine is no higher than in the general population that the benefits outweigh the risks, and that vaccinations should continue. They reviewed 18 cases of blood clots in the brain following administration of over 20 million doses of the AstraZeneca vaccine. This is a very rare complication which is associated with other vaccines also.

Moreover in India, there are no reported cases of blood clotting even after millions of people are given AstraZeneca’s vaccine.

There is strong evidence that the prevalence of blood clotting varies significantly among different ethnic/racial groups. The African-American people have a significantly higher incidence of blood clots, particularly following exposure to risk factor such as surgery, medical illness, trauma, etc. Probably vaccination might also be a trigger for clot formation in some of them. There are reports of clot formation even after taking vaccines manufactured by other firms. Compared to African-American people, Asians/Pacific Islanders have 70% lower prevalence of blood clot formation. This may be areason why clot formation is not reported in Indian people who have taken the vaccine.

As the COVID 19 infection can cause more harm to sick people like your Dad, it may be wise to go for vaccination. As your Dad is also on blood thinners, the chance of clot formation if at all provoked by COVID19 vaccine is almost none.

Vaccine and allergies

• I am 47 years of age, house wife. I have been taking medicines for allergic asthma. My problem becomes severe during the onset of summer and is less at other times. My doctor suggested I should take the COVID 19 vaccine but I am scared that the vaccine might cause asthma. I have read that there can be severe allergic reaction to vaccine.

It is known that people with moderate to severe asthma may be at higher risk of getting very sick from COVID-19 infection. To protect from the infection by COVID19 virus and to lower the risk of severe disease if infected, it is important for people like you with asthma to get COVID19 vaccine. There are no reports that people with asthma get the attack of asthma after taking COVID 19 vaccine. People with asthma may experience the same, relatively mild side effects people often report after receiving the vaccine, such as a headache, chills, a sore arm, fatigue, or fever. People with allergies to other medications, foods or inhalants also can receive the COVID19 vaccine. Normally after vaccination, people are kept under observation for not less than 30 minutes at the facility of vaccination to observe for allergic or any other reactions. Most of the reactions, if any will be immediate. This is the normal precaution followed.

Only those people with severe allergic reaction to the contents of the vaccine should not receive the vaccine. For this the manufacturers of vaccines have given the details of the ingredients in their vaccines. These are in a very small quantity but they can cause a reaction if one is really allergic to them. The Covishield vaccine manufactured by Serum Institute, Pune has: L-Histidine, L-Histidine hydrochloride monohydrate, Magnesium chloride hexahydrate, Polysorbate 80, Sucrose, Ethanol, Sodium chloride, Disodium edetate dihydrate (EDTA), Water for injection. Bharath Biotech’s Covaxin has: aluminum hydroxide gel, TLR 7/8 agonist (imidazoquinolinone), 2-phenoxyethanol, and phosphate buffer saline.

Common people would not have been exposed to these contents of the vaccines and hence allergies to the ingredients of the vaccines are unlikely.

Why no side-effects

• I have read that people get side effects after vaccination. My Dad who is 67 took vaccine at a Government Health Centre and he did not have any side effects. Does that mean his immune system did not respond or the vaccine was not working? Are the vaccines supplied at the Government facilities not potent?

The side effects of the vaccine are not uniform. There are many people who do not experience any side effects beyond a sore arm. In some trials more number of people reported side effects after the second dose than the first one.

A lack of side effects does not mean the vaccine is not working.During the vaccine trials, a significant number of people did not report side effects, and yet trials showed that about 70 to 90 percent of people had developed antibodies against the virus. Nobody really knows why some people have a lot of side effects and others have none.

In our country the vaccines are supplied from a single nodal point to both private and government facilities in that area. Contrary to some rumors, private establishments do not get a more potent vaccine from a different source. The vaccines available at Government facilities are the same ones available at private establishments.

Infection after vaccination

• There are reports that the people get sick and are tested positive even after getting two doses of COVID 19 vaccines. Recently more than ten doctors at Bangalore Medical College were tested positive after completing the full course of vaccination. Are these vaccines really preventing infection? I have serious doubts about the efficacy of the vaccines.

It has to be remembered that the available vaccines are not 100% effective. It is reported that Covishield vaccine used widely in our country is about 63% effective during the trial stages whereas the Covaxin is 81% and the mRNA vaccines available in US and Europe are more than 90% effective. The efficacy looks at the ability of the vaccine to protect the inoculated population using various parameters — ranging from the ability of the vaccine dose to prevent mild to severe symptoms, even if one gets infected, to preventing from getting infected with the disease altogether. The efficacy in the field (actual use in the public) may not be the same as in the trials because of transport and storage. It may be significantly less.

When we say that a vaccine is 80% effective, it means about twenty of the one hundred persons who have received the vaccine may still get the infection and become sick. But the vaccine protects the remaining 80 of the 100 people from infection. Unless we get a vaccine which is 100% effective, infection and illness may be still seen among those who have received the vaccine.

Therefore it is important to continue public health mitigation measures (masking, physical distancing, daily symptom screening, and regular testing), even in environments with a high incidence of vaccination, until herd immunity is reached at large.

Vaccine for youngsters

• Do healthy young individuals need vaccination? It was reported during the first wave that they would remain asymptomatic and even if they get the illness, it would run a milder course.

There are reports that infection by COVID19 virus in vaccinated persons, irrespective of their age and comorbidities, runs a milder course. Many of them (more than 80%) may not get sickness at all.

But the most important matter is that the transmission of virus from them to others is significantly reduced after vaccination. During the first wave of COVID19 infection, many asymptomatic persons, most of them being young and healthy, transmitted the virus to susceptible (elderly and sick) persons and made them seriously ill.

Now during the second wave the infection is seen in many of the young and healthy people and severe illnesses have been reported in them.

It is now believed that unless we achieve herd immunity by vaccinating 70% to 90% of the people, the menace of COVID19 infection may persist.

Considering these points it is important for all the eligible people to get vaccinated. In our country the vaccine is being rolled out in a phased manner and the third phase has just started. Soon people of age less than 45 may also get the vaccine. When it becomes available it is better to receive it.

Which vaccine better: Covishield or covaxin?

• Initially there were hesitations to promote Covaxin as the trial results were not known and Covishield was promoted by all. As the Covaxin is entirely manufactured in India and as per ‘Athmanirbhar’ claim there appears to be a strong support to this vaccine now. Which of the two is better? Is there any research support to the claims of superiority of the one over the other?

Both the vaccines have shown more than satisfactory results ever since the inoculation started in India. At the trial stage both the manufacturers claimed that their vaccines are 70% to 80% effective. However when used in public both the vaccines appear to be similar in their efficacy as well as side effects. We may have to wait for few more months to state categorically which of the two are better or both are same.

Covaxin is manufactured by Bharath Bio-Tech of Hyderabad. This vaccine is developed with inactivated COVID 19 virus. The vaccine contains inactivated viruses, which cannot infect a person but still can teach the human immune system to prepare a defense mechanism against the active virus. The vaccine with inactivated pathogen is the conventional method. There are several vaccines for some other diseases as well which are made using the same technology. Some of these are vaccine for seasonal influenza, rabies vaccine, polio, pertussis etc.

Initially when Covaxin was approved for emergency use, experts wondered how a vaccine was cleared for emergency use on vulnerable people when its trials were still underway. The All India Drug Action Network at the time said that it was "baffled to understand the scientific logic" to approve "an incompletely studied vaccine". It said that there were "intense concerns arising from the absence of the efficacy data". This message was spread in social media and people had lot of concerns over the use of this vaccine.

Dr Guleria, Director of All India Institute of Medical Sciences took both the doses of Covaxin and our Prime Minister also took second dose of Covaxin on 9th of this month. With this the doubts of the efficacy of this vaccine has declined and now many people are opting for Covaxin. As you said, this vaccine is prepared in our country and there is justification to support and use it as it is effective.

Covishield has been prepared by Serum Institute of Pune by using the viral vector platform which is a totally different technology. This technology is imported one from AstraZeneca. In this method, a chimpanzee adenovirus – ChAdOx1 – has been modified to enable it to carry the COVID-19 spike protein into the cells of humans. This cold virus is basically incapable of infecting the receiver but can very well teach the immune system to prepare a mechanism against such viruses. Here only a part of the COVID19 virus is enters the human body and not the entire virus.

There are claims that covaxin may be better as it uses entire virus, but these claims have no research support. While Covishield and Covaxin come with their own pros and cons, at present it appears that there is no one better than the other. Both are equally safe to use. In light of the present situation, what matters the most is being inoculated against the COVID19 virus, irrespective of which vaccine has been administered.

Gap between two doses

• The Covishield vaccine second dose was initially given at an interval of 21 days. Now it is recommended to be taken after a month. Why two doses are needed? Why there is confusion about the gap between two doses? Is this only for Covishield or Covaxin also?

The vaccines train the human immune system to prepare antibodies to fight against the real viruses if they enter the body. For this to happen effectively the immune system needs a ‘booster’ dose. The second or more doses are known as booster doses. There are several other vaccines like MMR (mumps-measles-rubella), polio given to children, hepatitis A and B given to all and so many other vaccines also need booster dose.

The COVID19 infection is new, so also the related research. New results of the studies and new evidence are emerging and whenever they are available, they are brought into practice. Because of the infectivity and complications of the disease, we are not in a position to wait for complete studies or trials.

The previous trials have shown that an extended interval of up to 12 weeks demonstrated greater efficacy of Covishield vaccine, which was also supported by immunogenicity data.

The latest trial included two doses Covishield administered at a four-week interval, which evidence suggests administration of the second dose with an interval longer than four weeks could further increase efficacy and accelerate the number of people who can receive their first dose. The Indian Government authorities have recommended that protection is enhanced if the second dose of Covishield is administered between 6-8 weeks, but not later than stipulated period of 8 weeks.

Increasing the gap between two doses is only applicable to Covishield. For Covaxin, the existing gap between doses (4-6 weeks) between two doses is maintained. These recommendations may be reviewed in future based on the research reports.

Also read: 

• COVID19 vaccine: Side-effects, co-incidences, rumours, benefits - By Dr Edward Nazareth
• Approval of COVID19 vaccines, safety concerns - By Dr Edward Nazareth
• COVID19 mutation and its impacts - By Dr Edward Nazareth
• When will we get COVID 19 vaccine? - By Dr Edward Nazareth
• Second wave of COVID19: Are we prepared? - By Dr Edward Nazareth
• Home care: Living with COVID19 positive - By Dr Edward Nazareth
• Positive, negative & negative positive-reality of COVID-19 tests - By Dr Edward Nazareth
• COVID-19 vaccine-expectations and reality - By Dr Edward Nazareth
• Common cold, common flu or COVID-19 - What next? - By Dr Edward Nazareth
• Children, COVID-19 infection and school reopening - By Dr Edward Nazareth
• Immune system, COVID 19 infection, and building up immunity - By Dr Edward Nazareth
• Asymptomatic, pre-symptomatic, and living with coronavirus