VACCINE EFFICACY AND COVID MUTATION

Scientists were concerned early in the epidemic, fearing that the coronavirus may evolve into something more deadly. Unfortunately, that worry was verified in November 2020 when the first "variant of concern" was found. The newly identified variation, also known as COVID-19 - B117, has been linked to a large increase in cases particularly in London and south-east England and many other parts of the world. 

So, in this blog, I’ll be talking about COVID Mutations and what it means for us. So, Let’s begin by taking a brief look at mutations and how they occur.

In biology, a mutation is something that causes a change in the genetic material. Each and every element of a cell's existence is controlled by the same genetic material. A cell's genetic makeup determines how it develops, functions, behaves, responds, and finally dies. These mutations can occur for a variety of causes. It can occur as a result of errors, radiation damage, or chemical exposure.

In fact, mutations can happen at any time. As a result, mutations might be harmful, neutral, or even beneficial to an organism.

So, you might be wondering how Coronavirus is affected by mutation?

Well, the coronavirus attaches to our body's cells using a specific protein. Spike proteins are proteins that aid the COVID virus in latching onto human cells and initiating infection. Because of mutations in these proteins, the virus is able to adhere to our cells more firmly, making it more infectious. 

Furthermore, mutations in this area allow the virus to avoid our body's own immune system, allowing it to spread unchecked. This mutation has been termed as ‘E484K,' and as of December 1, 2021, the UK recorded a total of 14000 instances each day, with a decreasing trend. 

After this strain on 5th Jan 2021 – UK was reporting a record high 60000 cases per day with an increasing trend. It has been discovered that the new strain is more infectious than the previous ones. According to the CDC. "Multiple lines of evidence show that B.1.1.7 is more effectively spread than other SARS-CoV-2 variants". According to UK Biobank researchers, most patients infected with COVID-19 maintain the antibodies for three to six months.

Your antibodies may not be able to protect you if you come into touch with another strain of the virus, such as the extremely infectious variety from the United Kingdom, and physicians feel your risk of reinfection is considerable. This is concerning because it raises the risk of coronavirus reinfection, especially in severely or chronically sick individuals.

What does this mean for us in the present? 

Things appear to be on the mend for the time being. The need of fast and decisive action appears to have been recognised across the world. Countries shut off overseas travel as soon as the news of the new strain became public, particularly from the United Kingdom. Those who had already returned were tracked down, quarantined, and tested as soon as possible.  Even nations like India, where covid has already impacted over 10 million people, have successfully halted the spread of this alien strain.

What about the vaccine? 

Well, things are a little strange here. Studies were conducted in New York, Texas, and Cambridge to determine the efficacy of current vaccination alternatives against the new strain. They evaluated freshly vaccinated people' antibodies against the novel covid 19 UK strain. Their findings revealed that, while the vaccine's efficacy in protecting against versions harbouring the E484K mutation was somewhat decreased for some persons, it was still within acceptable limits for the majority of people. It's worth noting, however, that the research mentioned above are based on relatively tiny sample sizes, so any conclusions drawn aren't conclusive.

What does this mean for the future? 

This mutation is a foretaste of what's to come. Covid's future will be filled with fresh shocks and unknowns. The long-term effects of this epidemic are yet unknown. It's possible that another altered strain isn't far behind. On a more optimistic note, all hope is not gone; we have fresh information and experience with which to prepare.

We have global mass vaccination programmes that are coordinated by corporations all around the world and sponsored by governments, and they have the ability to permanently address this problem. To reduce the load, we're looking into medicines, novel therapies, and complementary and alternative medicine. Governments are actively taking efforts to eradicate this illness, such as mass media campaigns, raising public awareness, boosting health spending, and working with scientific specialists.

Is Sinovac (and Other Covid Vaccines) Effective Enough?

 Is Sinovac (and Other Covid Vaccines) Effective Enough? & Do We Need Booster Shots FOR DELTA VARIANTS?

We know that the first covid19 vaccines 

were a welcome development during the pandemic because they were the ones that offered hope to an end for this pandemic. But, what we know is that these vaccines would keep us safe and protected against severe disease but there's a lingering question among us as to how long will the production last would variants make these vaccines available to us less effective? 

Another question would be, Would everyone need a booster shot in six months or in a year or in two years so could some people get away without that boost? or it is advisable for all these are actually the same questions that headlined the meeting of the Centers for Disease Control and Prevention Advisory Committee on immunization practices. 

What we know of as of now that the group isn't making recommendations around covid-19 vaccine boosters, but the discussion shows how leading health experts are thinking through these issues. So, let's go through them one by one. 

Here's what we know so far that the vaccines authorized by the World Health Organization (WHO) based on clinical studies work extremely well at protecting the majority of people from coronavirus infection. We know that the protection seems to last a while but, we're not sure quite how long. What we know so far that protection lasts longer than flu vaccination of which we give flu vaccination to our patients with diabetes every year. 

So far, data at present also shows that the shots still work against coronavirus variants even the fast moving delta variant. However, there are special groups of people where the vaccines don't work as much as we want them to work and these include people who are immunocompromised, particularly, people who had organ transplants. These people often don't produce antibodies after regular doses of covid19 vaccines and thereby neuro research have shown that third booster of covid19 vaccine could give more protection to these groups of immunocompromised people. That's the group that CDC seems to think could be the first to get a booster because we have clear signals that it could help these groups of people to protect against covid-19. Then after we learn more about how long the protection lasts for everyone else or if new variants emerge experts could hammer out details about boosters for the rest of us. 

In short at present, there's really no data to support recommendations for booster doses except for the caveat in severely immunocompromised hosts who are not able to mount a strong immune response. For other patients especially the general population, what we know for now is that the data will come later and that ongoing studies are tracking the durability of covid-19 vaccine protection and the CDC is watching to see if any variants evade the vaccine at present. 

Ongoing studies are tracking the durability of covid-19 vaccine production. For example, the CDC is watching to see if any variants invade vaccines and second several studies are present are ongoing  to check if people should get a third dose of the covid19 vaccine that already exists or a new shot with an updated form of the vaccine that targets specific variants. Most experts do agree however that if we start to see an uptick of infections or re-infections for people or new infections in people who have been vaccinated, that's a clue that we need to move quickly. 

Covid-19 vaccines are likely to be rolled out in UK in the fall to avoid another winter surge. Seven different vaccines are being tested in volunteers in England in the world's first booster study. So we have to await the data of booster shots. What we also know is that more transmissible variants including the Beta strain that emerge in South Africa require higher antibody titers to prevent infection. Prompting vaccine makers including Pfizer and Moderna to test whether tweaked versions of their existing shots will provide broader immunity. 

We also have data that one dose of the Novovax variant directed vaccine may provide sufficient protection against these strains in individuals previously immunized with against covid-19. So the modified shot has also the potential to provide broad protection against various strains if used as a primary vaccine regimen and this is one exciting new vaccines that soon will hopefully be rolled out across the world which is Novavax.   

As for SINOVAC, it is the primary vaccine that we're given that has been given to most of the general population. We now know that based on a second phase clinical trial produced by synovac company the third dose of Sinovac's inactivated vaccine can increase antibody response tenfold in a week. The study showed that the volunteers who had received two doses of Sinovac covid-19 vaccine and then received a third shot after three to six months, the antibody response inside the body's soared tenfold in a week and 20 fold in 15 days. It has been shown that after completing the two shots clearly, our body is producing very robust immune memory. 

Sinovac vaccine and the company will however conduct more thorough and longer periods of research to determine the best time to receive the booster for the general public based on the analysis of early vaccinated groups to combat the threat of mutant strains. Data from people vaccinated six months ago is now being analyzed and preliminary results show that antibody levels and about half of them are still good within that specific period. But the general concern at present is not whether to give booster shots or not. 

The CDC is pretty worried about the troubling rates of vaccination in the world. Only 17.7 percent of the world is vaccinated. In fact, if you look closely at the data clearly we have a long way to go in terms of vaccination but there are certain areas in the world like Israel where in majority of the patient population have already been vaccinated. We still have a long way to go to get the population protection. 

We know that unvaccinated people don't need the boosters because they really need their first shots and we need to convince this unvaccinated people to help protect the community by getting their shots having more people vaccinated will definitely slow the spread of the virus and prevent new variants. It will protect people who are immunocompromised too, when everyone around them is far less likely to have covis-19. Therefore, they are at far lower risk of catching it. Figuring out boosters definitely is important but getting unvaccinated people their shots right now is a very critical way to protect everyone prior to going around giving vaccines or giving everyone boosters we really need your help in convincing your friends and your relatives that hopefully they can get their vaccines and we can in general improve the overall vaccination rate.

New Covid-19 Cases Raise Concerns About Immunity

Throughout the pandemic, athletes have been the most tested population on the planet, sometimes providing examples of emerging theories about COVID-19. And as countries around the world continue to fight back COVID-19, attention has turned to Tokyo where the Olympics are under way. One challenge some athletes are facing: testing positive for the virus, despite having been vaccinated. This isn't the first we've heard of this.

What are chances of getting COVID-19 after receiving a vaccine?

Well, you've got a better chance of buying a winning lottery ticket but it happened to Warriors player Damion Lee. He will be out at least two weeks. It was not a false positive as first thought, even though Walman had been vaccinated. Yankees GM Brian Cashman says that three players tested positive and three others are likely infected. About 85% of the team is vaccinated, including those who have the virus.

These examples are known as breakthrough infections, which occur when someone tests positive for COVID-19 at least two weeks after getting their final shot.

Do these breakthrough cases mean the vaccines are failing?

No, the vaccines are not failing. The vaccines are working extremely well, and as expected. They do protect the majority of recipients from severe disease. That's what vaccines are designed to do: Prevent death and severe disease.

But most vaccines, including those created to fight COVID-19 don't completely protect you from infection. So it's not all that surprising that breakthrough infections are showing up. As of July 12th, more than 159 million people in the US have been fully vaccinated. CDC data suggests just under 5,500 have had breakthrough infections, resulting in hospitalizations or deaths. That's one in approximately 29,000 people who have been vaccinated.

Breakthrough infections are something that we want to monitor but in terms of their overall influence in the pandemic, they play a much smaller role than transmission among people who haven't been vaccinated. But these cases raise questions about our immunity to the virus and hint at a future in which it isn't gone completely and we learn to live with it. That's due in part to variants.

Research shows that variants, including Delta, can partially evade the immune response from prior infection and vaccination. We mount a really good immune response against the virus that our body's trying to recognize. Your body is really good at recognizing and neutralizing those specific threats. But when the virus starts to change, sometimes it doesn't recognize the virus as well. And so that's how you sort of see it chip away at that immune response. That's one of the reasons that health officials are really sort of concerned about this global vaccination drive in order to prevent the virus from spreading, both to save lives and to prevent it from further mutating and evading immune response.

The Delta variant is the most contagious version of the virus to be identified, but research suggests that full vaccination is still protective against severe disease and death: the outcomes that have made COVID-19 so devastating. 

What dictates whether someone is more likely to get infected, even if they're vaccinated?

Dr. Hatziioannou says there are four main variables. 

First is the amount of virus that is circulating in your community. So if a great number of people around you are infected, then the possibility of you getting exposed obviously increases. If you're in close proximity with people that are infected, particularly those that are unvaccinated and have generally higher viral loads, then the probability of you getting infected increases.

Second is tied to vaccine uptake, So if a large proportion of the population is vaccinated, then your virus transmission, virus loads, everything decreases. So the chances of spreading the virus amongst this population obviously decreases. That's because vaccinated people act as a kind of shield, even when they do get infected. A recent CDC study found that vaccinated people carried less virus and potentially didn't spread it as much as unvaccinated people. Cases were also shorter and less severe. Vaccines help create a kind of immune memory of what a virus looks like, helping the body fight it off more quickly when it spots it. That makes it harder for the virus to spread overall. Roughly half of all Americans are fully vaccinated but in some states and globally, the vaccination rate is much lower, giving the virus more opportunity to spread and mutate. That's why having large gathering, like concerts or the Olympics can be so challenging from a public health perspective.

Third, individual behavior matters. So as measures have been abandoned, such as masking and social distancing, when you don't have a significant number of the population vaccinated, then the ability of the vaccines to protect you from getting infected decrease.

Finally, even after vaccination, individual immune systems vary in their ability to prevent and fight off infection. Older and immunocompromised people seem to be more susceptible to breakthrough cases, and those tend to be severe. That's why health officials are considering additional doses right now, primarily for people who have a compromised immune system and might not have produced a good immune response after two doses of the vaccine.

Breakthrough cases might be asymptomatic or mild, so people may not know to get tested. But that's not the case for athletes. We're actually seeing breakthrough infections happen a lot more amongst sports teams, like baseball or for the Olympics because those are the people that get tested pretty regularly, even if they're vaccinated.

At the Olympics, organizers of the games are scrambling to deal with a rising load of athletes and officials who are testing positive upon arrival in Japan, some with breakthrough infections. The vaccination rates are low in Japan. Cases there are rising and organizers didn't require those participating to get vaccinated.

Dr. Hatziioannou and many other experts remain concerned that holding a large-scale international event prior to reaching a critical mass of vaccinated individuals has the potential to contribute to the virus's spread around the world. The Olympics is a special event and it's truly remarkable that it brings all these people from all these different countries together but it also poses a perfect ground to mix variants and spread the virus that will then go back to each athlete's country.