Vaccine about corona vaccine: ‘vaccine will not work for everyone’

If you can use some optimism, listen to the words of physician and hospital director Marcel Levi, in charge of fighting corona crisis in 17 London hospitals.

He expects a corona vaccine to be available before the end of the year. “I am still convinced that it is not unlikely that vaccines will be available around mid-December,” Levi said on Sunday in the TV show Buitenhof.

Oxfordvaccin

Some vaccines are well into development. One of the front runners is the vaccine developed by pharmaceutical company AstraZeneca and the University of Oxford, known as the Oxford vaccine for short. Levi is involved in the testing of this vaccine. “So I know about how good they are, about how safe they are and at what stage of development they are.”

Levi is also optimistic about its effectiveness. The vaccine gives an “excellent antibody response” in ‘almost everyone’ when administered twice, the doctor said.

‘Vaccine may not work for everyone’

Kate Bingham, chair of the UK Vaccines Task Force, is tempering the enthusiasm. We do not know at all whether there will ever be a vaccine, she writes this week in the medical journal The Lancet. “It is important to guard against complacency and over-optimism.”

According to Bingham, we must be prepared for the vaccine not to provide 100 percent protection. The vaccine may only reduce symptoms. Or maybe it doesn’t work at all for some people, or it only provides protection for a very short time.

Effectiveness

We come to an important point here. Many people believe that they are completely protected against the virus for a period of time after a vaccination. That is actually never the case, says Gorben Pijlman, virologist at Wageningen University, to RTL Nieuws. “Of course you always want to have the highest possible effectiveness. But it is not 100 percent with vaccinations against the regular flu, and not even with polio, mumps and measles.”

The studies that have now been set up aim for a vaccine to reduce the chance of infection by at least 50 percent. In other words: it works for some, not for others.

There is a chance that the effectiveness will even be 40 percent. “Then we probably still don’t have enough herd immunity to fully control the disease,” said Marc Bonten, physician-microbiologist and member of the Outbreak Management Team, yesterday in a letter sent to NRC.

‘Saves a sip on a drink’

Still, Pijlman thinks that a lower percentage can still be effective. “If you vaccinate a large part of the population, whereby a large percentage of the population does not really get sick anymore, then that still saves a sip on a drink. That really helps you. Then you may end up below the reproduction number 1 much faster. ” As an example, he cites the malaria vaccine, which scores low in effectiveness but can save many lives.

Six producers, four leaders

So far, the European Commission has made agreements with six vaccine manufacturers to purchase vaccines. The first four are in the third and final crucial phase of the investigation.

  1. BioNtech & Pfizer (end of 2020)
  2. AstraZeneca & Oxford (end of 2020)
  3. Modern (end of 2020)
  4. Janssen & Johnson & Johnson (begin 2021)
  5. Sanofi & GSK (2021)
  6. CureVac

Only small quantities will likely be available by the time the vaccines hit the market. It is expected that an ample supply of vaccines for the EU Member States will only become available in the course of 2021. Source: KNVM.

‘Effectiveness decreases in the elderly’

Marc Bonten of the OMT raised more questions about the effectiveness of the vaccines. To what extent do we know whether the vaccines also work for the weak or the elderly? According to Bonten, vaccines are now mainly tested on healthy people.

“The healthier (and younger) the participants, the greater the chance that the vaccine will be effective, because for almost all vaccines effectiveness decreases with age.”

Older people are ‘definitely’ included in vaccination studies, says Pijlman. He heard it today from Hanneke Schuitemaker. She is head of viral vaccines at Janssen, part of Johnson & Johnson – the other frontrunner in the development of a corona vaccine. “They have several clinical phase studies with different age cohorts. This includes older groups.” The first signs are favorable.

‘Hope for the elderly’

Also the Financial Times came this week with good news: “Oxford vaccine research offers hope for the elderly,” the newspaper headlined. Two sources close to the study reported that the vaccine provides a “robust immune response” in this group.

And so you hear varying reactions week after week about the development of the vaccines. In a few weeks’ time, we could learn more about the results of the final and crucial phase of many vaccine studies.

He understands that Arrowman colleagues warn against too much optimism. “A good vaccine against HIV has still not been found. It remains wishful thinking that we will have a very effective vaccine in a year. But we all hope so.”

Share on facebook
Facebook
Share on pinterest
Pinterest
Share on twitter
Twitter
Share on linkedin
LinkedIn
Share on email
Email

Comments

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.