Half dose of mRNA booster still very effective, says top virologist
Half the dose of an mRNA vaccine can provide as much immunity as a full dose, a top virologist said recently.
In a Facebook post on Saturday, Chulalongkorn University’s Dr Yong Poovorawan said studies show that administering half a dose of an mRNA vaccine, especially Moderna, is just as effective as a full dose.
He added that in the US and Europe half doses or 50 micrograms of the vaccine are being administered as boosters.
He also pointed out that the Thai Food and Drug Administration had approved the administration of half doses and even indicated this on the label.
Hence, he said, people are within their rights to ask for half a dose even if their first two shots were of an inactivated vaccine like Sinovac or Sinopharm.
Yong went on to say that the Public Health Ministry has also approved the administration of half a dose or 15mcg of Pfizer vaccines as booster shots. This decision was backed by studies conducted by Chulalongkorn University and Siriraj Hospital.
He said the study conducted by Chulalongkorn’s Centre of Excellence in Clinical Virology found that half a dose of an mRNA vaccine as a booster provides sufficient immunity.
The peer-reviewed Vaccine journal is looking into publishing this study, while it has already been published on the MedRxiv website https://bit.ly/3up4VA2.
