On May 27, Wang Huaqing, chief expert of the immunization program of the Chinese Center for Disease Control and Prevention, responded to an online discussion about "leukemia after vaccination with the new crown vaccine is related to vaccines".

  On May 27, the Joint Prevention and Control Mechanism of the State Council held a press conference.

At the press conference, a reporter asked: We are concerned about such discussions on the Internet. Some people who develop leukemia after receiving the new crown vaccine believe that the disease is related to vaccination. How do experts view such a statement?

  In this regard, Wang Huaqing said that in fact, after vaccination, some symptoms and diseases, including leukemia, have anything to do with the vaccine, and two things must be done when determining:

  The first thing is to standardize the process.

The second thing is to have a basis for judgment.

In terms of process, after vaccination, when it is suspected that there are symptoms and related diseases related to the vaccine, a report should be made and reported to the vaccination unit.

After receiving the report, the inoculation unit will conduct an investigation. This investigation is carried out by an expert group composed of experts from multiple fields to do the relevant investigation, and during the investigation process, it is necessary to collect all relevant information, including vaccination information, It also includes past medical history, as well as some clinical manifestations and corresponding test results.

What kind of disease it is, it needs to collect and investigate complete relevant information.

  In addition, who is to judge whether it has anything to do with the vaccine, that is, the abnormal reaction we call it?

It is also an expert diagnosis group composed of multidisciplinary experts, who make analysis and judgments based on the survey results and survey content.

Generally, in the process of judging adverse reactions or abnormal reactions, six aspects should be considered.

What everyone pays more attention to is the relationship in time, that is, the vaccine is given first, and symptoms or diseases appear later. This is the first premise.

  The second factor to consider is the rationality of biology. For example, why do we not vaccinate people with immunodeficiency in principle with live attenuated vaccines, because live attenuated vaccines are theoretically and biologically based. There may be an increased risk of abnormal reactions in these immunocompromised individuals, which is biologically plausible.

  The third is the strength of the association.

We all know that two data may look different, but in statistical analysis, either there is no difference or there is a difference, and another situation is whether the difference is significant, which belongs to the strength of the association, which is our The third thing you need to do when determining an abnormal reaction.

  The fourth thing, the occurrence of abnormal reactions actually has its regularity. Like drugs, there is a dose-effect relationship. If the content is large, the probability and intensity of a certain reaction will be high.

Some mRNA vaccines currently used in foreign countries have different antigen content. If the antigen content is large, the probability of general reaction is higher, and there are more cases such as fever.

  Another factor to consider is the consistency of the association. To put it simply, whether these people who have been vaccinated have similar symptoms or diseases, and these similar symptoms and diseases are higher than its threshold level, That is to say, this situation occurs in both vaccinated and unvaccinated people, but whether there is a higher incidence among vaccinated people is the consistency of the association.

  As a final point, consider the specificity of the association.

Specificity in association is often the only reason to say the vaccine is the only one.

For example, if you have an immune deficiency, you may develop disseminated tuberculosis after taking the BCG vaccine, which is tuberculosis caused by the vaccine.

But why does it cause?

Because this person has a severe immunodeficiency, and the BCG vaccine is a live vaccine, this condition occurs, which is specific to the association, which means that the vaccine may be the only cause of the disease.

  Finally, Wang Huaqing emphasized that if you feel unwell after being vaccinated, especially if it lasts for a long time and the symptoms are severe, you should go to the doctor immediately.

Second, if we suspect that it has something to do with the vaccine, we have corresponding personnel to investigate, and after the investigation, we will also make judgments based on the six aspects just mentioned, and this judgment is not a judgment of one person, it is Judgments are made by a panel of multidisciplinary experts.

The abnormal vaccine reaction and its diagnosis are still in the process of understanding and need to be continuously improved, but to make judgments, it is an expert group composed of multidisciplinary experts to make judgments.

(Produced by Li Jiali)

Responsible editor: [Li Ji]