No data on Sputnik first dose efficacy: Prof. Malavige
By Buddhika Samaraweera
No data is available on the efficacy of administering only the first dose of the Russian two-dose Sputnik V Covid-19 vaccine, immunologist Prof. Neelika Malavige, who is attached to the Sri Jayewardenepura University’s Immunology and Molecular Medicine Department, told The Morning yesterday (10).
She added that the vaccine has been shown in clinical trials to be 91% effective, and that the full protection afforded by it is only likely to be achieved upon the administration of both doses. The Sputnik V vaccine is manufactured by the Gamaleya Research Institute of Epidemiology and Microbiology.
However, in a communication to The Morning, Prof. Malavige said that the first dose too would give some level of protection.
“For Covid-19 vaccines with two doses such as the Oxford AstraZeneca Covishield vaccine of India and the Pfizer-BioNTech vaccine, there is data showing that there is a certain degree of protection received after a single dose, until the second dose is administered. Therefore, the first dose of Sputnik V too is likely to give some protection. However, complete protection is only likely to be achieved after administration of both the doses. Further, the efficacy trials for Sputnik V have been conducted using both doses.”
An incident was reported recently where a consent form was issued to people at a vaccination centre in Kundasale, Kandy, with a condition stating: “I wish to even take only the first dose of the Sputnik V vaccine.”
However, when contacted by The Morning, Public Health Services Deputy Director General and Health Ministry Communications Director Dr. Hemantha Herath said that the Epidemiology Unit is currently reviewing whether a second dose of the Sputnik V vaccine is necessary, as they have received information from the Gamaleya Research Institute that the first dose may be sufficient to provide immunity against Covid-19.
Prof. Neelika Malavige also noted that many vaccines such as those given for measles, mumps and rubella (MMR), and chickenpox are also two dose vaccines.
“However, from other vaccines, such as the ones for MMR and chickenpox, we know that children, after a single dose, are protected from developing severe diseases from these viruses, although once again, complete immunity only comes after the administration of both doses,” she added.
Noting that the country is now in a pandemic situation and also that there are insufficient vaccine doses available for all citizens, Prof. Malavige said that in the event of a delay in the administration of the second dose of the Sputnik V vaccine, it would be rational and logical to have even partial immunity, rather than to have no immunity.
“I believe that the current data from Sri Lanka shows that only a very few individuals who have received only a single dose of the Covishield vaccine have developed severe disease symptoms and died. Therefore, although based on the current data, two doses are required for protection even with the Sputnik V vaccine, given the extraordinary circumstances that we are in, it is better to have some immunity than no immunity,” she elaborated.
Last month, Sri Lanka commenced administering the Sputnik V vaccine after it received the first batch of 15,000 doses. Some other consignments of the vaccine were later received and the Production, Supply, and Regulation of Pharmaceuticals State Ministry Secretary Dr. S.K. Ratnayake said that about 65,000 doses of the Sputnik V vaccine would also be delivered to Sri Lanka by the end of the coming week.