COVID-19 : Coronavirus vaccine: what are the risks of not getting the second dose

Over the past few days, news of various politicians and authorities who have administered the first dose of the vaccine without being part of the group to which it corresponds vaccinate. As a consequence, some of these people have resigned after the controversy. But, the big question that arises now is whether they should get the second dose or wait their turn, even if it takes more than two weeks.

The first dose provides insufficient protection

Adelaide Sarukhan, PhD in immunology and scientific writer of the Institute for Global Health (ISGlobal), is in favor of administering the second dose, despite the fact that the first was given irregularly. “Is something that should not happen, but it is preferable that those who have already received the first dose now receive the second, ”he stated in 20 minutes. An opinion based on “scientific criteria and evidence to date.”

First, he argues that the first dose does not guarantee immunity by protecting much less than it should. In the case of Pfizer and BioNTech vaccine, for example, generate a 52% effective according to the companies themselves, while a group of Israeli researchers determined that it was 35% effective. In either case, it is an insufficient level of protection.

Likewise, the expert recalls in 20 minutes that in the United Kingdom the debate on putting a single puncture to protect more people was opened, although this protection is intermediate. A possibility that Sarukhan rules out because he considers that the ideal is to achieve high protection: “It is better vaccinate few people well that means good to many ”. Also, with a single dose the organism is more exposed to new variants, like the British, the South African and the Brazilian, which are transmitted faster. More antibodies are needed to protect against these strains.

Appearance of new mutations

The second reason why Sarukhan thinks that this vaccine should be administered is that not reaching an “optimal level of antibodies could favor the appearance of new variants”. The coronavirus has been shown to constantly mutate, and some variants can spread faster or be more deadly. In this way, as immunity grows in the population, the SARS-CoV-2 will have a higher “selective pressure” to escape immunity, and an organism with low protection will allow it to replicate and give way to new mutations. “It has been seen that the virus accumulates mutations in individuals with an infection that lasts two or three months, ”explains Sarukhan.

On the other hand, Salvador Macip, a researcher at the University of Leicester and a professor at the Open University of Catalonia, disagrees with Sarukhan. He thinks these people should get the second dose when it comes time because there is no evidence that the fact that a person does not receive the second dose increases the chances of mutation of the virus. More research is needed on this. In addition, it estimates that the people who have improperly received the vaccine are very few and are a risk to the population.