COVID-19 Delta variant 'slightly complicates' herd immunity goal, says OCTA expert

Published June 23, 2021, 4:18 PM

by Ellalyn De Vera-Ruiz


Vaccinations against the coronavirus disease (COVID-19) must take on greater urgency as the more transmissible Delta variant has put a slight complication on the country’s target for herd immunity and population protection, OCTA Research fellow Dr. Guido David said on Wednesday, June 23.

He said that the country’s requirement for vaccinations is increasing because the variant that is spreading in other countries is highly infectious.

“Yung Delta [variant] medyo naco-complicate yung herd immunity na target natin and yung population protection (The Delta variant somewhat complicates the herd immunity that we are targeting, as well as the population protection we are hoping for),” David said in a DZBB interview on Wednesday, June 23.

OCTA’s report noted that doubling the country’s current average of 195,400 vaccinations daily can lead to “population protection” by Christmas.

OCTA has been recommending the vaccination of 40 to 50 percent of the population in high-risk areas to achieve population protection by the end of the year. Once population protection is achieved, the COVID-19 attack rate will be less than 1 in 100,000.

Meanwhile, herd immunity against COVID-19 can be achieved if 70 to 80 percent of the population is vaccinated. The COVID-19 attack rate is almost zero once herd immunity is achieved.

“That being said, effective pa rin [ang lahat ng] vaccines sa Delta variant pero bumababa nang konti yung efficacy pero hindi naman ganun kababa (all vaccines are still effective against the Delta variant but the efficacy may decrease slightly but not that low),” David said.

“Parang mga nasa (It is about) 80-90 percent [efficacy] pa rin depende sa vaccine (depending on the vaccine). May mga iba na mas mababa (Others have lower efficacy rate),” he added.

He cited that countries like Israel and the United Kingdom, which have already reached population protection against the Alpha and Beta variants, are starting to see surges in their cases due to the growing presence of the Delta variant that was first identified in India.

The Alpha and Beta variants were first detected in the United Kingdom and South Africa, respectively.

“Nakuha nila yung population protection against sa Alpha, Beta variants pero yung Delta variant nakaka escape sya ng vaccine nang konti (They got the population protection against the Alpha, Beta variants but the Delta variant managed to escape the vaccine a bit),” David said.

“Ang sinasabi nila ang karamihan ng tinatamaan ay yung hindi pa bakunado at yung nakafirst dose pa lang kaya importante na makumpleto and second dose (What they are saying is that most of those infected are those who have not been vaccinated and those who only have the first dose. That is why it is important to have our second dose of vaccine,” he said.