World Health Organization (WHO) has advised against mixing and matching COVID-19 vaccines of different pharmaceutical companies.
While addressing a press conference, WHO’s Chief Scientist, Dr. Soumya Swaminathan, termed the practice as a ‘dangerous trend’ and said there is little to no data available regarding the health impact of this practice.
She noted that the world is in a data-free and evidence-free zone where mixing and matching of different COVID-19 vaccines is concerned, adding that the situation could spiral out of control if citizens started deciding when and which COVID-19 vaccines they would receive.
WHO’s warning comes a day after Saudi Arabia allowed people vaccinated with Chinese vaccines to enter the Kingdom only after receiving a booster dose of a Saudi-approved vaccine. Saudi Arabia has permitted entry to the recipients of Sinopharm and Sinovac after receiving a booster dose of either Pfizer, AstraZeneca, Johnson & Johnson, or Moderna.
Mixing Vaccines Boosts Immune Response
Contrary to WHO’s a warning, an Oxford University study last month found that administering mixed doses of Coronavirus vaccines increases the immune response by 4 times in comparison to the immune response generated after administering the initial and booster doses of the same COVID-19 vaccine.
Similarly, some EU countries have already started administering alternatives to AstraZeneca as the second dose after the vaccine was linked with rare and fatal blood clots in the brain. For instance, Spain and Germany are administering mRNA-based vaccines of Pfizer or Moderna as second doses in young adults who have already received the first dose of AstraZeneca’s vaccine.