Science, Art, Litt, Science based Art & Science Communication
Qs people asked me on science and my replies to them - part 217
Countering misinformation on vaccines
Q: Ma'am, I am getting several forwarded messages on social media regarding safety of COVID vaccines. It seems scientists have rushed through the procedures undermining the safety of the public. It normally takes several years to develop vaccines. But now these vaccines have been developed in just a few months. How can we trust them?
Krishna: Glad you asked me this Q. But first, stop forwarding these messages because many of them are 'opinions' and 'fears' that have no evidence. In science only data and evidence counts, not opinions. They will harm people more and make them reject vaccines altogether.
OK, in olden days you have bullock carts for transportation. They would take you from Kanyakumari to Kashmir in a few months. Earlier people used to travel by boats and ships. They would take you from India to America in a few months. Then - as the modern science and technology improved - came other modes of transport like buses, trains and finally aeroplanes. Now you can reach far-off destinations in a few hours.
Now if people say bullock carts are safer because they are slow and take you to your destination in a few months than aeroplanes which rush you to your destination in a few hours? How silly that sounds?
Yes, earlier it used to take several years for new vaccines to come into the public domain.
For those who are unfamiliar with the methodical process of clinical research, the process can feel torturously slow. First, researchers must study the structure and infectious behaviour of a pathogen. Then they figure out how to get the human body to best produce an immune response to fight against it. Next, the vaccine is tested for safety and efficacy—first using cell, animal and mathematical models, and later in human clinical trials involving thousands of participants. Only then can the approval process begin.
Scientists used "new methods" now to develop vaccines for COVID 19 and therefore could bring them to public domain in a very short time. There lies the difference.
Moreover, vast knowledge and earlier experiences make you move things faster. It should also be reassuring that nearly 200 years of vaccine development has generated a number of highly effective and safe vaccine platforms, requiring less time and effort to produce new kinds of vaccines. Recycling existing vaccine technology allows researchers to focus their time on identifying the best targets that will produce the strongest immune response with the fewest side effects.
The biggest misconception is the work on the vaccine started when the pandemic began. The work started years ago.
The world's biggest Ebola outbreak in 2014-2016 was a catastrophe. The response was too slow and 11,000 people died. The world should have done better.
In the recriminations that followed, a plan emerged for how to tackle the next big one. At the end of a list of known threats was "Disease X" - the sinister name of a new, unknown infection that would take the world by surprise.
One example is Oxford vaccine. The Jenner Institute at the University of Oxford - named after the scientist that performed the first vaccination in 1796, and now home to some of the world's leading experts - designed a strategy for defeating an unknown enemy. Scientists there were planning how can we go really quickly to have a vaccine in someone in the shortest possible time.
They did achieve that with the vaccine for covid 19.
The central piece of their plan was a revolutionary style of vaccine known as "plug and play". It has two highly desirable traits for facing the unknown - it is both fast and flexible.
Conventional vaccines - including the whole of the childhood immunisation programme - use a killed or weakened form of the original infection, or inject fragments of it into the body. But these are slow to develop.
Instead the Oxford researchers constructed ChAdOx1 - or Chimpanzee Adenovirus Oxford One.
Scientists took a common cold virus that infected chimpanzees and engineered it to become the building block of a vaccine against almost anything.
Before Covid, 330 people had been given ChAdOx1 based-vaccines for diseases ranging from flu to Zika virus, and prostate cancer to the tropical disease chikungunya.
The virus from chimps is genetically modified so it cannot cause an infection in people. It can then be modified again to contain the genetic blueprints for whatever you want to train the immune system to attack. This target is known is an antigen.
ChAdOx1 is in essence a sophisticated, microscopic postman. All the scientists have to do is change the package.
It sounds strange to say it, almost perverse, but it was lucky that the pandemic was caused by a coronavirus. This family of viruses had tried to jump from animals to people twice before in the past 20 years - Sars coronavirus in 2002 and Mers coronavirus in 2012. It meant scientists knew the virus's biology, how it behaved and its Achilles heel - the "spike protein". So scientists had a huge head start.
The spike protein is the key the virus uses to unlock the doorway into our body's cells. If a vaccine could train the immune system to attack the spike, then the team knew they were odds-on to succeed.
And they had already developed a ChAdOx1 vaccine for Mers, which could train the immune system to spot the spike. The Oxford team were not starting from scratch.
If this had been a completely unknown virus, then the scientists would have been in a very different position. It was also fortunate that coronaviruses cause short-term infections. It means the body is capable of beating the virus and a vaccine just needs to tap into that natural process.
If it had been a long-term or chronic infection that the body cannot beat - like HIV - then it's unlikely a vaccine could work.
On 11 January, 2020, Chinese scientists published and shared with the world the full genetic code of the coronavirus. The team now had everything they needed to make a Covid-19 vaccine. All they had to do was slip the genetic instructions for the spike protein into ChAdOx1 and they were good to go.
Earlier publication of work used to take a lot of time. So the waiting time to get new information was several months or years. Now scientists are using "Preprint servers". These are online archives, or repositories, containing works or data associated with various scholarly papers that are not yet peer reviewed or accepted by traditional academic journals. Papers offered on these kinds of repositories undergo basic screening and are checked for plagiarism. Once posted, articles are typically citable and cannot be removed. Readers can explore these newly posted “preprint papers” and upload comments. Preprint servers are therefore a great way for researchers to share and receive feedback on scholarly works in progress. This cut a lot of time in knowledge sharing by scientists. There was tremendous co-operation between scientists across the world to speed up things.
Then they used Artificial Intelligence to prepare models and to get to a solution in the shortest possible time.
The Pfizer and Moderna vaccines are based on a new technology called mRNA approach.
How do mRNA vaccines work?
Vaccines train the immune system to recognize the disease-causing part of a virus. Vaccines traditionally contain either weakened viruses or purified signature proteins of the virus.
mRNA vaccines are new.
mRNA vaccines work by providing the genetic code for our cells to produce viral proteins. Once the proteins, which don’t cause disease, are produced, the body launches an immune response against the virus, enabling the person to develop immunity. mRNA can theoretically be used to produce any protein, with the upside that it much simpler to manufacture than the proteins themselves or the inactivated and attenuated versions of viruses typically used in vaccines, making it an appealing technique. It could, in theory, be used to engineer any protein the body needed to boost immunity against pathogens and fight diseases such as cancer and rare genetic conditions.
An mRNA vaccine is different, because rather than having the viral protein injected, a person receives genetic material – mRNA – that encodes the viral protein. When these genetic instructions are injected into the upper arm, the muscle cells translate them to make the viral protein directly in the body.
This approach mimics what the SARS-CoV-2 does in nature – but the vaccine mRNA codes only for the critical fragment of the viral protein. This gives the immune system a preview of what the real virus looks like without causing disease. This preview gives the immune system time to design powerful antibodies that can neutralize the real virus if the individual is ever infected.
While this synthetic mRNA is genetic material, it cannot be transmitted to the next generation. After an mRNA injection, this molecule guides the protein production inside the muscle cells, which reaches peak levels for 24 to 48 hours and can last for a few more days.
Now another important thing in vaccine development is funding. But as the pandemic progressed and caused huge economic losses all around the world, funds started flowing in!
Finally what takes more time is safety check.
Quality control is never the easiest part of a project, but researchers cannot start giving an experimental vaccine to people until they are sure it has been made to a high enough standard. At every stage of the manufacturing process, they needed to ensure the vaccine was not being contaminated with viruses or bacteria. In the past this had been a lengthy process.
Once animal trials show the vaccine 's safe, the researchers will be able to begin human trials of the vaccine.
There is a pattern to clinical trials:
- Phase one - the vaccine is tested in a small number of people to check it is safe
- Phase two - safety tests in more people, and to look for signs the vaccine is producing the required response
- Phase three - the big trial, involving thousands of people, to prove it actually protects people
Okay, the recent covid vaccines have undergone all these trials. What hasn't happened to cut time is years of hanging around in between each phase.
To accelerate development, many COVID-19 vaccine trials are conducted in studies that combine phases 1, 2 and/or 3 where researchers begin by vaccinating a smaller number of healthy volunteers. As the trial continues, if the vaccine appears to be safe, it then opens up to more participants, such as those with preexisting health conditions. Large-scale phase 3 efficacy trials ultimately include tens of thousands of volunteers. The current trial lineup includes a variety of vaccine types—both tried-and-true models as well as next-generation approaches.
The notion that it takes 10 years to trial a vaccine 's really misleading. Most of the time, it's a lot of nothing. Most probably waiting for funds to arrive ( governments usually take hell of time to release funds), waiting for volunteers to agree, slow analysis of data, and what not. If we can tackle these problems we can as well cut a lot of waiting time. How you manage these things makes lots of difference. An emergency makes people work faster. That 's what has happened here.
This is how one vaccine researcher puts it:
A long process of writing grant applications, having them rejected, writing them again, getting approval to do the trial, negotiating with manufacturers, and trying to recruit enough people to take part. When you are lucky enough to get trials funded, you then spend months on submitting to ethics boards. It can take years to get from one phase to the next.
The process is long, not because it needs to be and not because it's safe, but because of the real world.
Next time somebody expresses concern at the astonishing speed the vaccine trials have happened at, point out to them that ten years isn’t a good thing, it’s a bad thing. It’s not ten years because that is safe, it’s ten hard years of battling indifference, commercial imperatives, luck and red tape. It represents barriers in the process that we have now proved are “easy” to overcome. You just need unlimited cash, some clever and highly motivated people, all the world’s trial infrastructure, an almost unlimited pool of altruistic, wonderful trial volunteers and some sensible regulators and of course very dedicated scientists (2).
Let me also tell you this:
Safety has not been sacrificed. Instead the unparalleled scientific push to make the trials happen, the droves of people willing to take part, and of course the money blew many of the usual hold-ups aside.
That does not mean problems will not appear in the future - medical research cannot make those guarantees. Usually, side-effects of vaccines appear either at the time they are given or a few months afterwards. It is possible that rarer problems could emerge when millions of people are immunised, but this is true of every vaccine that has ever been developed.
This is because each biological entity is different. If it is safe for you, it might not be safe for your friend because s/he differs (in the way his biology- biochemistry works) from you. No medicine or vaccine is hundred percent safe to all living beings.
What is more important is Lab results always differ from Public domain results because several unknown factors govern the latter. Unless you see the second set you cannot say anything with certainty.
Only after weighing all these things, and only when the positives outweigh the negatives, vaccines are brought into the public domain.
The final delay could be because of giving regulatory approval and manufacturing the vaccine. These things have also been dramatically speeded up. Even while the trials 're going on, manufacturing has already been started!
The Oxford vaccine has - like those of Pfizer and Moderna - arrived in record time to a world in desperate need.
Russian sputnik V and Chinese vaccines are already in the public domain and showing promising results.
The Pfizer vaccine was administered to 21,999 people. Some people reported a reaction similar to the one after the seasonal flu vaccination, but so far no serious side-effects have been reported. But how can we be sure that this holds if the treatment is rolled out to millions of people?
Statisticians came up with the “rule of three”. The rule tells us that if 21,999 participants were treated with no side-effects, then with 95% confidence, the probability of a side-effect from the vaccine is expected to be less than three (hence the name) divided by 21,999 and so less than one in 10,000. The chance of these side-effects is probably even lower, but the researchers will be keen to extend the trials further to confirm this (1).
Most modern vaccines are relatively safe provided the scientists' guidelines are strictly followed. There is no need to worry.
Covid 19 is a multi-organ disease*. In vulnerable people it ravages the whole body leaving them suffer their entire remaining lives or even kill them. When you consider that facing minor issues of vaccines is not a big deal.
* Read here all about it: covid-19-is-not-just-a-respiratory-disease-but-a- multi-organ disease
Finally people are asking me questions like, "Do you take these vaccines?" "Which one is the best?"
'Yes!' will be my reply to the first Q. :)
But first they will be given to the people who need them the most like front line workers like doctors, nurses, and paramedical staff. Then to the elderly. Finally by the time it reaches us, it will take a few more months or even a year.
By that time we will have more data to compare, analyse, and decide.
Then only I can tell you which one I will choose and why. Meanwhile please watch this video which tells why comparison is not the right way at the present moment
Any effort to rank the vaccines must take into account not only their reported effectiveness, but also supplies, costs, the logistics of deploying them, the durability of the protection they offer and their ability to fend off emerging viral variants. Even so, many people might find it hard to look away from clinical-trial results that suggest an efficacy gap.
And there are more than 100 vaccines that are at various stages of development now. You have a lot to choose from.
So watch this space and don't spread misinformation, don't forward it at all, and if you still have doubts ask me, not your neighbour or friend.
We might need at least 70% of people to be vaccinated to reach “herd immunity” — the point at which a pathogen stops spreading because there are so many people protected it cannot make its way to the people who are still susceptible. Please help us reach that goal.
Mail ID to send your queries
kkartlabin@gmail.com
Watch these videos to know why vaccines are important to control diseases
Updates:
2/12/2020
UK approves Pfizer–BioNTech vaccine
The United Kingdom is the first country to approve the COVID-19 vaccine developed by phar....
Footnotes:
1. https://theconversation.com/covid-19-vaccines-are-coming-how-will-w...
2. https://theconversation.com/less-than-a-year-to-develop-a-covid-vac...
--
16/1/21
Which vaccine is given in India for Covid?
Two vaccines have been given emergency approval for India's immunisation programme: the Oxford/AstraZeneca vaccine, known in India as Covishield, and a domestic product, Covaxin, developed by the pharmaceutical company Bharat Biotech.
Views: 576
Replies to This Discussion
-
Permalink Reply by Dr. Krishna Kumari Challa on
-
480
What is vaccine efficacy?
Pfizer vaccine: what an ‘efficacy rate above 90%’ really means
There was – rightfully – a lot of excitement when Pfizer and BioNTech announced interim results from their COVID vaccine trial. The vaccine, called BNT162b2, was reported to have an “efficacy rate above 90%”. This was soon translated in the press to be 90% “effective” at preventing COVID-19. Efficacy, effectiveness – what’s the difference?
We academics are very precise in our language and it can be a cause of considerable frustration when the media doesn’t appreciate the important distinction between certain terms. I was recently asked not to use the term “efficacy” for my radio interview because “listeners won’t understand what it means”. Sometimes accuracy can get in the way of clarity, so it’s important to know when to let these things go. However, now is perhaps the time to draw a clear distinction between efficacy and effectiveness.
In short, efficacy is the performance of a treatment under ideal and controlled circumstances, and effectiveness is performance under real-world conditions.
Clinical trials are precise and neat, and aim to answer if a vaccine is safe and if it works. To achieve this, the participants who are recruited to have the vaccine (or a placebo) are likely to be generally healthy. In early clinical trials, participants may not be the intended vulnerable group of people we are aiming to protect eventually with this product, for example, children or older people with other conditions.
To work out vaccine efficacy we must compare it to a “control” treatment, which is usually an irrelevant or known vaccine or similar preparation that shouldn’t work for the tested virus. The trials are often “double-blinded” so the participants don’t know which vaccine they received, and the researchers don’t know which vaccine they administered until the end of the study.
The Pfizer/BioNTech vaccine reports 90% efficacy, which means that – of the 94 confirmed cases of COVID-19 – their vaccine prevented COVID-19 symptoms for 90% of those who received the vaccine compared with placebo. This is very high and will probably change by the end of the study. The press release reported the results for 94 participants – they need 164 to complete the trial, which shouldn’t take long. Safe vaccines with efficacy above 50% are expected to be approved for COVID-19.
So what do we mean by vaccine effectiveness? Monitoring of vaccines does not stop after they are approved for use. When the vaccine is deployed, data will continue to be collected to study how well it works over the years for all vaccinated people.
Important parameters include vaccine performance for different groups (age, ethnic background, other conditions), duration of protection (duration of immunity and effectiveness against evolving virus strains), the balance of benefit against harms. Cost effectiveness is also an ongoing consideration, based on comparisons with other vaccine and treatment options.
We don’t know what the overall effectiveness of the vaccine will be in preventing COVID-19 symptoms, severe disease or deaths, and it may be several years before studies report on the effectiveness of BNT162b2 for different groups. However, it is unlikely that it will be 90%.
But then very few vaccines – aside from measles and chickenpox – are 90% effective. The flu vaccine is around 40%-60% effective, but it still saves millions of lives. And that’s something to celebrate.
https://theconversation.com/pfizer-vaccine-what-an-efficacy-rate-ab...
--
How effective is the vaccine?
It is not easy to find out how effective a vaccine is. First, researchers need to know whether just an act of injecting somebody can help. The trials involve a large number of people, with half of them given a vaccine and the other half a placebo. Then the participants need to be exposed to the infection with the expectation that most of those in the control group become ill, but vaccination protects at least some in the treated group.
In some cases, such as for HIV or Ebola, even giving a placebo can be ethically controversial as they have such a high death rate. For coronavirus, the researchers need to rely on natural infection because no study, at the moment, intentionally exposes participants to the coronavirus. As a result, the efficacy calculation is based on a relatively small number of those who caught COVID-19 by contact with other infected people.
Vaccine efficacy reflects a proportion of the number of those who became ill in the vaccinated group and in the non-vaccinated group.
https://theconversation.com/covid-19-vaccines-are-coming-how-will-w...
--
https://theconversation.com/how-mrna-vaccines-from-pfizer-and-moder...
--
Q: If scientists can make a vaccine in 1 year, then why don't they use this technology for all vaccines, but only for the COVID-19 vaccine? If it is possible to make a vaccine in 1 year, why do they spend 5-10 years, instead of 1 year?Several things:
- The world didn’t “invent a COVID vaccine in one year.” You’re not seeing the years of research that went into a SARS vaccine. SARS is also caused by a coronavirus, so much of that research could be used against SARS-CoV-2.
- New technology. Why did it take seven hours to render one frame of video when Toy Story came out, but now it can be done in a minute? New technology. The COVID vaccine is the world’s first mRNA vaccine. mRNA vaccines are a new technology that allows us to make safer vaccines faster than the old-fashioned system of using attenuated or inactivated viruses.
- Huge money. You can sometimes speed up research by throwing money at it. Most vaccine research programs are underfunded and understaffed. This one wasn’t. You’d be surprised how many problems are soluble in a solution of Benjamins.
- Testing a vaccine for efficacy is easier during a pandemic. Efficacy tests are cohort tests. You give half your sample group a placebo and half a vaccine and then wait. At the end of a period of time, you see how many people in each group have become infected with the disease agent. If the disease is rare, this takes a lot more time than if the disease is common. The more virulent the disease, all other things being equal, and the more widespread the disease, the faster this study can be done, because the more opportunities there are for people to contract the disease.
-
-
-
The Promise of mRNA Vaccines
Long before Moderna and Pfizer’s COVID-19 shots, scientists had been considering the use of genetically encoded vaccines in the fight against infectious diseases, cancer, and more.
mRNA vaccines work by providing the genetic code for our cells to produce viral proteins. Once the proteins, which don’t cause disease, are produced, the body launches an immune response against the virus, enabling the person to develop immunity. mRNA can theoretically be used to produce any protein, with the upside that it much simpler to manufacture than the proteins themselves or the inactivated and attenuated versions of viruses typically used in vaccines, making it an appealing technique. The concept of using mRNA to produce useful proteins to fight disease has been around for decades. But until now, no vaccines using this technology have made it this far in clinical trials. The success of the SARS-CoV-2 vaccines is really good for the RNA field, because until very recently, there were just a handful of people who really believed in mRNA vaccines. “We now have the chance to really prove [their usefulness] in an actual outbreak situation.”
https://www.the-scientist.com/news-opinion/the-promise-of-mrna-vacc...
--
There are two very advanced COVID vaccines coming from China — Cansino has an adenovirus based delivery vector similar to that used by the Oxford/AstraZeneca vaccine and has recently started a phase 3 study of it.[1] Sinovac has an inactivated virus based vaccine, that has been used at-risk already by some people in China and is currently being evaluated in a phase 3 study.[2]
--Putin orders 'large-scale' vaccinations in Russia from next week
Russian President Vladimir Putin told health officials Wednesday to start widespread vaccinations next week, adding that the country had produced close to 2 million doses of its Sputnik V vaccine. The announcement came the same day Britain approved the Pfizer-BioNTech vaccine for a rollout starting next week. Last week,Russia announced that interim test results showed the Sputnik V vaccine was 95 percent effective.UK approves Pfizer-BioNTech Covid-19 vaccine: Who gets it first?
UK gives Pfizer vaccine a shot: 10 things to know
--
https://www.quora.com/q/sciencecommunication/Qs-people-asked-me-on-...
--
'How a woman’s foot became anti-vaccine propaganda'
--
Life will not ‘go back to normal’ until at least half the population is vaccinated Save 52% when you subscribe to BBC Science Focus Magazine Coronavirus modelling indicates that even if high-risk groups are vaccinated, death rates and hospitalisations would continue if measures were relaxed before the virus had been controlled in the general population.
https://www.sciencefocus.com/news/covid-19-vaccine-uk-when-will-lif...
--
https://twitter.com/ScientistSwanda/status/1348337651083042820
--
The covid-19 vaccines have all been produced in a fraction of the time it 'normally' takes yet we assured no corners have been cut in doing so. If this is the case, why do 'normal' vaccines take so long? Why can't they be developed quickly too?Four things:
- The new vaccines are being developed using new gene sequencing technology and other biomedical technology that has only existed for a few years. These new techniques hugely speed up vaccine development.
- It’s very rare for large amounts of resources and lots of people to be thrown at vaccines. I hate to say this, but the fact is, most deadly viruses are a greater problem in developing nations than developed nations, so there simply isn’t a lot of will to develop vaccines fast. Most vaccine development programs are under-resourced.
- SARS-CoV-2 is similar to SARS. Vaccine development for SARS started many years ago, then was halted when SARS burnt itself out. The COVID vaccine program was able to use a lot of work that had already been done; we didn’t start from scratch.
- There isn’t usually a huge focus on vaccines because, contrary to what know-nothing antivax morons blather about on social media, there just plain isn’t a lot of money in vaccines. This pandemic, however, is destroying so many economies and killing so many people—including front-line healthcare workers—that there’s huge incentive to get a working vaccine.
-
-
-
-
-
Vaccine side effects are actually a good thing
--Q: Which one is a better vaccine, Covishield or Covaxin?
Krishna: You just can’t compare vaccines like that because clinical trials ‘re conducted under different conditions, not same. All are good in preventing hospitalization and death. Watch this video which tells you why ….
https://www.news-medical.net/news/20201026/Phase-1-trial-results-of... -
Badge
Birthdays
Birthdays Today
Birthdays Tomorrow
© 2024 Created by Dr. Krishna Kumari Challa.
Powered by
