Month: December 2020

The AstraZeneca adenoviral Covid-19 vaccine: What potential role does it have?

The results of the AstraZeneca adenoviral ChAdOx1 nCoV-190 vaccine trial published in the Lancet today are encouraging, even if the overall efficacy of 70% is lower than the 90-95% being reported for mRNA vaccines from Pfizer-BioNTech and Moderna; and from the Russian Sputnik adenoviral vector vaccine.

The AstraZeneca vaccine is cheaper than the mRNA vaccines and can be stored in a conventional vaccine fridge. Hence, it is an easier vaccine to use in primary care and community settings, including in low and middle income countries. The most commonly reported adverse reactions were fatigue, headache, feverishness, and myalgia. More serious adverse events were rare; none of which were thought to be due to either of the vaccines used in the study.

Based on these results, once the vaccine is approved by the MHRA, I would like to see it rapidly adopted by the NHS. The vaccine is highly suited for use in UK primary care as it can be stored in general practices and given to patients either opportunistically or in dedicated vaccination clinics. It can also be more easily used in care homes and for housebound patients than the mRNA vaccines.

There is ongoing research looking at vaccine combinations and if this research shows positive results, people may benefit from a second vaccine, such as an mRNA vaccine, after receiving an adenoviral vaccine. One caveat for all the Covid-19 vaccines is that we don’t yet know how long the immunity they generate will last. We also don’t yet know if they stop people being infectious.

Covid-19 vaccination – separating fact from fiction

Covid-19 vaccinations will kick off within days but it seems some people need a sharp dose of facts first. In an article published in the Daily Mirror, Matt Roper and I debunk some of the common myths and misconceptions about vaccines.

Scepticism about vaccines has been growing throughout the pandemic and a recent survey found that one in five British adults may refuse to take a coronavirus jab – even though it is probably our only hope of a return to normality.

  1. MYTH: A vaccine produced so quickly can’t be safe

Most vaccines take years to develop, test and approve for public use but, says Dr Majeed, a global effort has meant scientists have been able to work at record speed.

He says: “Covid-19 vaccines have to go through the same process of approval as other vaccines. Funding was made available immediately and studies set up rapidly.

“There have been a lot of technological developments that allow vaccines to be developed much more quickly.”

  1. MYTH: I might be allergic but won’t know until I get it

Azeem Majeed is professor of primary care and public health at Imperial College London

“Allergies to vaccines are very rare,” says Dr Majeed. “They are given safely to millions of people every year.”

The odds you’ll have a severe reaction to a vaccine is about one in 760,000.

Being struck by lightning next year is higher at one in 700,000.

Most reactions are because of some other component of the vaccine, such as egg protein, if the person is severely allergic.

3, MYTH: There haven’t been enough tests for people with underlying conditions

Dr Majeed says: “There are many vaccine trials taking place and they are being tested in people with different characteristics, such as age, sex, ethnicity and medical history.

“Results show they are safe in all groups they have been tested in.”

  1. MYTH: Vaccines can overload your immune system

In 2018 the myth was debunked by American researchers who examined the medical records of more than 900 infants from six hospitals.

 They found no link between vaccines given before the age of two and other infections in the following years.

 “Vaccines do not overload your immune system,” says Dr Majeed. “On the contrary, they generate an immune response that helps reduce the risk of infection, complications and death.”

  1. MYTH: The vaccine could actually give me coronavirus

Some vaccines contain the germs that cause the disease they are immunising against but they have been killed or weakened to the point they don’t make you sick.

In the case of a coronavirus vaccine, “none that are in development contain a live coronavirus,” assures Dr Majeed, “and they therefore can’t give you a coronavirus infection”.

  1. MYTH: If everyone around me is immune, I don’t need a vaccine

“It’s essential to achieve a high vaccine coverage so we create herd immunity,” says Dr Majeed. “If people refuse to be immunised, we will continue to get outbreaks of Covid-19.

“If you decline to be immunised, you may get infected and also infect the people you come into contact with.”

  1. MYTH: It’s better to be immunised by catching Covid

Dr Majeed says: “Vaccines have been shown to be very safe, whereas illnesses such as measles and Covid-19 can lead to serious long-term medical complications.

 “Vaccines have saved many lives and prevented people from being left disabled.”

  1. MYTH: Vaccinated children experience more allergic, autoimmune and respiratory diseases

This is another unfounded claim that has led some parents to delay or withhold vaccinations, says Dr Majeed.

 Studies examining many vaccines have failed to find a link with allergies or autoimmune disease.

 “Vaccines protect against many diseases and substantially reduce the risk of illness and death in children,” he says.

  1. MYTH: Some of those taking part in trials died

Stories that Dr Elisa Granato, one of the first participants in the human trials of the Oxford vaccine, died shortly after being injected, were shared millions of times.

 The news was false and she gave a BBC interview saying she was feeling “absolutely fine”.

 “Only one death has been reported among people taking part in trials,” says Dr Majeed.

 João Pedro Feitosa, a doctor in Brazil, was given the placebo rather than the vaccine and died of Covid-related complications.

  1. MYTH: The swine flu vaccine left people with side effects, so why would this one be safe?

A mass vaccination programme against swine flu in the US in 1976 led to increased chances of people developing Guillain-Barre syndrome, a rare neurological disorder.

 Dr Majeed says: “Covid-19 vaccines have been carefully tested in a large number of volunteers and found to be very safe.

 “Once they are more widely used, there will be monitoring of people who have received the vaccines to identify any future problems.”

  1. MYTH: Vaccines cause autism

 The idea that vaccines cause autism has long been disproved but the claims have recently been doing the rounds again.

 Last year a massive study from Denmark found no association between being vaccinated against measles, mumps and rubella, and developing autism.

 It is the latest of at least 12 other studies that have tried and failed to find a link.

 Dr Majeed says: “No evidence has ever been found that vaccines cause autism in children.”

  1. MYTH: The Spanish Flu vaccine led to 50 million deaths

During the 1918 pandemic it was the fact there was no vaccine that caused it to infect a third of the world’s population.

 In the 1930s scientists found it was caused by a virus, with the first vaccine developed a decade later.