Pfizer-BioNTech vaccine: All you want to know

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Dubai has launched a free vaccination campaign following the UAE’s approval for the coronavirus vaccine developed by Pfizer Inc. and BioNTech SE, a WAM report said, quoting the Supreme Committee for Crisis and Disaster Management. The first batch of vaccine arrived from Brussels on an Emirates SkyCargo flight on Tuesday, according to a tweet from Dubai Media Office.

The vaccine has received authorisation for emergency use from regulators in the United Kingdom, the United States, Canada and several other countries. During trials, the vaccine was found to be around 95 per cent effective in preventing COVID-19.

Here’s a look at the vaccine and its effects, according to reports from around the world.

What’s in the Pfizer-BioNTech vaccine?

The active ingredient is messenger Ribonucleic Acid (mRNA) which triggers the production of the protein found on the spikes of the new coronavirus (SARS-CoV-2).

The vaccine was designed on computers and synthesised in laboratories. So it’s synthetic, not natural since it’s not extracted from actual viruses or grown in a cell, like classic vaccines. This means it can be manufactured in large numbers very quickly, and can also be tweaked fast enough to keep pace with the virus’ mutations.

How does the vaccine work?

The vaccine enables the production of the “spike proteins” that sit on the coronavirus’ crown and is used to gain entry to cells. The mRNA in the vaccine provokes the production of spike protein in the cells of the human body, and the body responds by producing antibodies, and B cells and T cells are activated, according to Ugur Sahin, the chief executive of BioNTech that co-developed the vaccine with Pfizer.

How long will the immunity last?

The vaccine provides immune memory, which is the immune system’s ability to quickly recognise and attack a pathogen the body has previously encountered. The Pfizer-BioNTech vaccine can do that if it comes across the coronavirus again. But how long will that happen? It’s difficult to say since the vaccine has been rolled out only recently.

Sahin expects the protection to last “months or even years”. Eleanor Riley, professor of immunology at the University of Edinburgh, told New Scientist that people might need annual boosters.

Image Credit: Graphic News

Who should get vaccinated?

The vaccine is recommended for all people aged 16 years and above.

Who should not get vaccinated?

Pregnant women and children under 16 are not eligible for the vaccine, since it hasn’t been tested on them. And there isn’t sufficient data on the vaccine’s effectiveness in children under 15. But trials for these groups are planned or underway.

People with allergies: If a person has had a severe allergic reaction to other vaccines or injections, he/she shouldn’t get vaccinated. Seek the advice of a doctor, who will help decide if it is safe to get the vaccine.

Can breastfeeding mothers receive the vaccination?

There’s no definite answer. Breastfeeding women were excluded from the Pfizer, AstraZeneca and Moderna vaccine trials. So there’s no data how the vaccine would affect a breastfed baby.

The UK and the US have adopted contrasting approaches. The UK’s Medicines and Healthcare products Regulatory Agency has advised that breastfeeding women should not receive the Pfizer vaccine. In the US, the Advisory Committee on Immunisation Practices says that breastfeeding women may choose to receive the vaccine. The American College of Obstetricians and Gynecologists says: “Vaccines should not be withheld from lactating individuals who otherwise meet criteria for vaccination.”

Will it work on older people?

It will, as the efficacy in people over the age of 65 was found to be 94 per cent, much higher than what experts expected, according to the New Scientist. The trials included participants aged up to 85. The vaccine hasn’t been tested in people over 85.

What about children?

It is not known whether children will get protection from the vaccine. The trials included only people aged 18 or older. In September, children aged under 16 were included. A new trial on children as young as 12 has now been launched.

Will it protect people with health issues?

It is found to be very effective. The vaccine appears to protect people with comorbidities (pre-existing health conditions), including diabetes, cancer, hepatitis B, hepatitis C and well-managed HIV.

I’ve had COVID-19, do I need to vaccinate?

People who have had COVID-19 will have to vaccinate like everybody else. Typically, an infection causes better immunity than a vaccine, but not always. For example, the vaccines for tetanus and human papillomavirus provide better protection than from a natural infection.

The US Centers for Disease Control and Prevention says vaccination should be offered to people regardless of whether they had a prior infection. There’s no data on how long immunity to the coronavirus lasts, after an infection or a vaccination. And coronavirus infections are notorious for their shortlived immunity.

How many doses are required?

The Pfizer-BioNTech vaccine requires two injections, given 21 days apart, to prepare the immune system to fight off the coronavirus. It uses a prime-and-boost strategy: the first dose alerts the immune system, and the second one gets the system worked up.

The efficacy after the first dose is 52 per cent, and it rises to around 95 per cent after the second dose, according to the New York Times.

What happens if people miss their second dose?

Two doses are required, and the second is needed to gain full immunity. The gap between doses in the trial ranged between 19 and 42 days. Only 2 per cent of trial participants missed their second dose, so it’s not clear what happens in such a case.

How will you feel after vaccination?

There will be very mild side effects as with any vaccine when the immune system is activated. Symptoms include low-grade fever, headache, muscle ache, chills and fatigue. It’s because the immune system is responding to the vaccine. Please note that this doesn’t mean you have COVID-19 infection.

Do I resume normal life after vaccination?

Trials have shown that the vaccine prevents COVID-19 and reduces the severity of the disease. But it doesn’t indicate whether it will curb transmission. All safety protocols and infection control measures must be strictly followed even after vaccination. So continue wearing the masks and observe social distancing.

“This will not replace hygienic measures — it will be an adjunct to hygienic measures,” said Dr Paul Offit, a professor at the University of Pennsylvania and a member of the US Food and Drug Administration’s vaccine advisory panel.

Will the vaccine protect against the new variant?

The Pfizer-BioNTech vaccine should protect from the new strain as it targets the spike protein. When more mutations occur, the vaccine may need to be modified.

Dr Sahin said it would need at least two weeks to better understand how the mutations might impact the vaccine’s effectiveness. “We believe that there is no reason to be concerned until we get the data,” he added.

How soon will immunity develop after vaccination?

Immunity builds within four weeks after the first dose, although Dr Sahin says it appears to develop earlier. More details are awaited.

What happens to the vaccine?

The vaccine will be active for a few days and breaks down quickly. It doesn’t enter the nucleus in the cells of the human body.

Pfizer’s COVID-19 vaccine arrives in Dubai on an Emirates SkyCargo flight on Tuesday night.
Image Credit: Dubai Media Office

Why the vaccine requires complicated cold storage

All mRNA vaccines are highly fragile and should be kept at extremely low temperatures. Or else, it will disintegrate.

For long-term storage, the Pfizer-BioNTech vaccine has to be stored at -100F (-70C), and that requires specialist cooling equipment. Pfizer’s innovative distribution container keeps the vaccine at that temperature for 10 days if it’s unopened, according to a New Scientist report. The containers can be stored for up to 30 days if they are replenished with dry ice every five days. After thawing, the vaccine can be stored in a regular fridge for up to five days.

How fast can the vaccine be produced?

The full Pfizer-BioNTech vaccine dose is 30 micrograms (a microgram is a millionth of a gram). It will technically require only several months to produce two doses for the 7.8 billion people in the world. But it’s not that simple.

Pfizer’s chief executive, Albert Bourla, said that it could have 30 to 40 million doses of the vaccine before the end of the year, which would be enough for 15 to 20 million people. Pfizer and BioNTech say they could ramp up to 1.3 billion doses a year.

Will the vaccine end the pandemic?

No, not in the short term. But it will, eventually, a New Scientist report said. Even if the vaccines halt transmission and the symptoms, highly infectious diseases require very high immunity levels to break the “chain of transmission”, it said. So it’s difficult to put a time frame.