June 19, 2024

Medical Trend

Medical News and Medical Resources

Vaccination with two different COVID-19 vaccines is prone to adverse reactions

The Lancet: Vaccination with two different COVID-19 vaccines is prone to adverse reactions


Vaccination with two different COVID-19 vaccines is prone to adverse reactions.  Many COVID-19 vaccines have been approved and are in short supply. Can I get two doses of vaccines from different companies to achieve the immunization effect?

A recent study by The Lancet showed that the risk of adverse reactions such as fever, chills, fatigue or headaches is higher after vaccination with different vaccines, and no more serious safety issues have occurred.

According to Matthew Snape, associate professor of pediatrics and vaccinology at Oxford University and lead researcher of vaccines, vaccinating two different vaccines is one of the strategies to alleviate the temporary shortage of vaccine supply.

In addition, in view of the possibility of rare blood clotting reactions with the AstraZeneca vaccine, some countries such as Germany, France, Sweden, Norway and Denmark have changed their recommendations for the use of the vaccine. It is recommended that people who have received a dose of AstraZeneca vaccine receive Pfizer vaccine as an alternative. .

However, there are currently no data on the immunogenicity, reactogenicity, and safety of a mixed vaccination strategy globally.

In this study, the researchers recruited 830 healthy volunteers over the age of 50. Four groups were vaccinated. They were a two-dose AstraZeneca vaccine group, a two-dose Pfizer vaccine group, or a two-dose Pfizer vaccine group. Group, the first dose and the second dose are 28 days apart.

It was found that volunteers in different vaccine groups had more side effects after vaccination. 34% of people vaccinated in the AstraZeneca-Pfizer order reported a fever, while only 10% of the people in the two-dose AstraZeneca vaccine group reported; 41% of those vaccinated in the Pfizer-AstraZeneca order Fever was reported, compared with 21% of people in the two-dose Pfizer vaccine group. Other adverse reactions such as chills, fatigue, headaches, joint pain, discomfort and muscle pain have also seen similar increases.

Researchers told volunteers that paracetamol could be used to relieve pain, but they did not require preventive use. It was found that nearly 60% of volunteers vaccinated with two different vaccines used analgesics, while about 40% of those vaccinated with the same type of vaccine used painkillers.

These enhanced symptoms mostly appeared within 48 hours after the second dose, and there was no serious adverse reaction of the rare coagulation syndrome related to the AstraZeneca vaccine within one week after the vaccination. At present, researchers are still verifying the effect of the mixed use of Moderna vaccine and Novavax vaccine, and more research is needed to evaluate the immune efficacy of different vaccines after mixed use, and it is necessary to prove whether the above-mentioned increase in adverse reactions is a manifestation of enhanced immune response.

Matthew said that these adverse reactions are basically the same as the common reactions described in the instructions, but they occur more frequently. The incidence of some mild and moderate symptoms increased significantly, but these adverse reactions were quickly eliminated. All in all, this new discovery deserves attention, but it is not the result we expected. If you want to be vaccinated with two different vaccines, you need to be mentally prepared for absence from work the next day.

Currently, the US Centers for Disease Control and Prevention and the WHO do not recommend mixed use of the two vaccines, but the Centers for Disease Control and Prevention also indicated that its recommendations will continue to be updated as research progresses and new vaccines are launched. Dr. Jonathan Van-Tam, Deputy Chief Medical Officer of England, believes that the use of different vaccines can make vaccination promotion strategies more flexible. In some countries with larger populations, supply shortages are an inevitable problem. If this vaccination strategy can be approved by the drug regulatory authority, it will have obvious advantages for the promotion of vaccines.

There is also a possibility that the use of different types of vaccines can make the immune response stronger, produce higher levels of antibodies, and last longer. Of course, its effects need to be evaluated in more specific clinical trials. This research is the first step. A more in-depth understanding of vaccines will facilitate the use of vaccines to fight the intensifying epidemic.


(source:internet, reference only)

Disclaimer of medicaltrend.org