Expert says mixing vaccines a common practice, not harmful

A vaccine expert on Saturday said mixing different vaccines has long been a practice in the medical field and does not bring any harm to the patient, though clinical trials have yet to be done on the matter.

“Actually, it remains to be investigated, but there is no harm. In general, maraming mga nangyayaring ganiyan, even before. Hindi lang dito maaaring mangyari sa COVID. Kasi kaming mga pediatrician, doon sa mga bata nangyayari 'yan,” Philippine Foundation for Vaccination Executive Director Dr. Lulu Bravo said at a Laging Handa public briefing.

(Actually it remains to be investigated, but there is no harm. In general, a lot of things like that happen, even before. This could happen not only with COVID. We pediatricians observe that it is happening to children).

Bravo cited the example of the Pneumococcal Conjugate Vaccine (PCV), where PCV-13 could be used as an alternative if supply of PCV-10 runs out, and vice versa.

"No company has done a study where they would mix their vaccine with other vaccines," Bravo, however, clarified.

"That is never done before. But now with the pandemic, narinig ko na mayroon nang mga kumpanya, even our Chinese companies tsaka even 'yung ibang kumpanya nag-iisip na talaga na 'pag kulang 'yung bakuna at wala kang ibang magamit for the second dose, posible talaga na gagawa ka ng ibang brand or ibang bakuna at titingnan mo ngayon kung talagang ganu'n pa rin ang efficacy,” she added.

(That is never done before. But now with the pandemic, I heard that there are already companies, even our Chinese companies and other companies are thinking that if vaccines are lacking and nothing else could be used for the second dose, it is possible to produce a different brand or vaccine to check if the efficacy is really the same).

A vaccine's efficacy might increase or decrease or might stay the same if mixed with a different vaccine, Bravo said.

“Pero hindi masama, hindi makakasama kung makapag-iba ka or mabago. Ngayon, we usually think na kung magkamukha 'yung bakuna, baka pareho sila ng efficacy... It remains to be seen kung ano ang posibleng gawin ng mga kumpanya na magsasagawa nitong ganitong pananaliksik."

(“But it's not bad, it won't do any harm if a vaccine is altered or changed. We usually think that if some vaccines are the same, they might have the same efficacy... It remains to be seen what the companies that will conduct this research could possibly do.) -MDM, GMA News