Corona vaccines are being developed under great urgency around the world and the pressure is hard to get vaccines into production.

An extreme example is the Sputnik V vaccine developed in Russia, which was granted a marketing authorization tested on 76 people. No information has been received on its effectiveness.

Different vaccines for different groups

Researchers warn that the early introduction of “moderately effective” vaccines is hampering the development of “truly effective” vaccines.

– The fastest completed vaccines are the most experimental. It’s possible that they aren’t very good at protecting against the coronavirus, says a professor at the University of Bristol Adam Finn The Guardianille.

– However, it is difficult to prove this if a large number of people have already been given the first vaccine. Huge numbers of people are needed to find out which vaccine is best for which group, such as the elderly, says Finn.

Extensive tests already underway

There are currently 198 known coronary vaccine development projects around the world. At least four vaccines are in the final third phase of testing. These include Pfizer’s BNT162b2 and the Oxford University and AstraZeneca vaccine.

In the third phase, the vaccine has been given to tens of thousands of people and tens of thousands of people in the control group have received placebo. Participants themselves do not know if they are getting the right vaccine or placebo.

Results from these three-stage tests are expected in weeks or months. When the first drug is proven to provide effective protection against the coronavirus, the pressure is strong to use it immediately and extensively.

In the elderly, the vaccine may not be effective

The first phase is likely to vaccinate health care personnel and other groups at high risk of infection.

For example, older people have a weaker immune system.

“The problem is that early vaccine tests are unlikely to show how well the vaccine works in special groups, such as the elderly,” wrote the director of the World Health Organization. Kanta Subbarao In the journal Nature.

– We know that vaccines tend to work better in healthy young adults. The tests currently underway may also not provide information on how well the vaccines work for different ethnic groups, writes Subbarao.

Urgent use

The end result is that by the spring, many vaccines have passed the tests without knowing which vaccine and, for example, what dose is best for which group.

It is likely that a marketing authorization will be granted for a vaccine that appears to protect at least half of the vaccine recipients. It may be used on a large scale.

This will be followed by new vaccines that have taken more time to develop but may be more effective. However, demonstrating efficacy can be difficult when the first vaccines are already widely deployed and in a hurry.

“Just no one has realized that there will be a lot of confusion about vaccines in the coming months,” says the director of the vaccine unit at the Mayo Clinic of the Medical Research Institute. Gregory Poland To the New York Times.