Three years ago, the global Covid-19 pandemic caused by the coronavirus drastically altered the way we live our lives. We settled for a ‘new normal’. Apart from working from home, masks or sanitisation, if there’s one thing that in a way re-established its importance in our lives, it was the vaccine. In India, adults, who often do not opt for vaccination easily, had to take a vaccine shot during Covid, not once or twice, but thrice.
A recent survey by the Association of Physicians of India and Ipsos in 16 cities found that while 71% of adults aged 50 know about adult vaccines, only 16% of them have actually received them. While the adoption of vaccines in the adult population of India may be low according to the survey, the emphasis on vaccine adoption at a global level is not, given their effectiveness.
New Covid vaccines are still being made to cope with new mutations of the Omicron variant. Moderna, Pfizer, and Novavax are currently in the process of developing new vaccines against the highly mutated BA.2.86 variant, also known as “Pirola”. In fact, Moderna, on September 6 said that clinical trial data suggested that its revised COVID-19 vaccine is likely to be effective against the Pirola subvariant, which has raised concerns about a potential resurgence of infections.
The emphasis on vaccine adoption is not limited to Covid alone, as governments, pharma companies, medical experts and other stakeholders are encouraging their development and adoption for other existing diseases as well.
In a conversation with The Core, Dr Rashmi Hegde said that vaccines could also play a role in healthy ageing in future, in addition to healthy diet and exercise. “There are vaccines available for different diseases that happen in the older age group, like pneumonias like flu, like including tetanus, diphtheria, all those diseases and also for shingles,” she added.
In April, GlaxoSmithKline Pharmaceuticals (GSK) launched its top-selling shingles vaccine Shingrix in India, to prevent the disease, shingles, in adults over 50 years. According to the Mayo Clinic, shingles is a virus that can give you a painful rash. This rash can appear anywhere on your body, but usually, it looks like a line of blisters around either the left or the right side of your torso. Caused by the varicella-zoster virus — the same virus that causes chickenpox — shingles isn’t life-threatening but it is painful. After you've had chickenpox, the virus stays in your body for the rest of your life. And years later, the virus may reactivate as shingles. Vaccines can help lower this risk of shingles, as per the Mayo Clinic.
GSK’s Shingrix for the prevention of shingles (herpes zoster) and post-herpetic neuralgia in adults aged 50 years and above is one such vaccine. According to GSK, clinical trials have shown that Shingrix is highly effective, with an efficacy rate of over 90%.
The Core’s Govindraj Ethiraj spoke to Dr Rashmi Hegde, executive vice president of medical affairs at GSK to understand more about the new vaccine, its effects, and if we are likely to see more vaccines to address disease conditions, as preventives rather than curatives that we are used to.
Here are edited excerpts from the interview:
What is shingles? Why is it suddenly back in the news? And is it as common as we hear it is?
So shingles is the common term that is used in layperson's language, but it is also known as herpes zoster. This is caused by the activation of the ‘Varicella Zoster’ or the chickenpox virus. So usually, children experience chickenpox, they suffer from chickenpox in childhood, and sometimes they may have chickenpox without having the rash. So, there may not be any clinically visible disease or clinically visible chickenpox, and this virus then stays dormant in the nerve cells for life. So with age what happens is that the immune system of human beings we have something known as immunosenescence, the immune system weakening and when there is weakening of the immune system, the inactive virus becomes active and causes shingles. And roughly about 30% of people over the age of 50-60 years will suffer from shingles at least once in their lifetime.
So you're saying whether you had a visible rash or not, you could be a candidate for shingles at this point, or only those who did not have the rash are more likely to be candidates at this point.
You have something known as subclinical infection and a subclinical infection is where you don't manifest the science of infection. For example, if a person has hepatitis, and hepatitis is usually visible as jaundice, right? And a person could be having subclinical hepatitis which means the person will not be having any signs of jaundice. So no yellowing of the eyes, but if you do the liver function parameters, they will show that the liver enzymes are raised. So similarly, one could have a subclinical shingles or chickenpox infection, not shingles, the chickenpox infection. That's been true also about Covid right during Covid. There were a lot of people who didn't show signs of the infection but they probably had some subclinical infection and therefore, you know, they were immune to getting a second attack of Covid.
Now that you mentioned Covid, it is obviously very transmissible. Is shingles also similarly transmittable or transmissible?
No actually. If there is a person who has shingles, he has a rash over the body and these are vesicles they are filled with fluid, and this fluid will contain the chickenpox virus. So if an individual A has shingles and individual B, who has never had shingles, or chickenpox comes in contact with individual A, then if the vesicles are open and the fluid is transmitted, of course, it requires very close contact, then the person B could get chickenpox, but not shingles.
And would I know whether I have the virus in me right now, whether it's dormant within me, assuming that I had suffered from chickenpox?
So we say that 90% of people over the age of 50 years have the virus dormant in their body, there's less than 10%. And these are global figures. So I think in India, you know, with our high population, I think even more than that would be positive for the chickenpox virus.
How would the vaccine work in the case of shingles?
So the vaccine helps to deal with the virus, which is within the nervous system cells. So these are cells within a certain part of the spinal cord. And the vaccine helps to prevent the disease being transmitted, it produces antibodies, and it subjugates the virus.
When something like this is administered at this time, is it more of a cure? Or is it a vaccine, which also prevents something happening in the future?
It's not a cure. So for example, if a person with shingles comes and takes the vaccine, now that does not make him better for the episode of shingles that he has now. But if the person takes two doses of shingles vaccine, the vaccine for shingles, then at the end of one month after the second dose, we say that the person has the chance of having 90%+ immunity.
Looking ahead, we are of course seeing vaccines as a solution as a preventive solution to many diseases and Covid was, of course, the best example that we're all familiar with. So is that something that you see a lot now or going ahead in the way science is going as well?
So a diet vaccination as part of the healthy ageing spectrum. You know, people are talking about healthy ageing all over the world. And as you know, there are people who are trying to also prolong life. But the important thing about prolonging life is to be able to have healthy years to that life. There's no point in having a long life without being healthy and able to do all the things that one wishes. So as part of this healthy ageing, there is of course diet, exercise, and there is sleep. And finally, there is a vaccine. So, there are vaccines available for different diseases that happen in the older age group, like pneumonias like flu, like including tetanus, diphtheria, all those diseases and also for shingles.