When will our life return to normal?
Returning to the “old normal” would be achieved, according to an OCTA fellow Fr. Nicanor Austriaco, once “containment” and “herd immunity” are attained in the country.
During the “Race Against Time: The Road to Herd Immunity” webicon hosted by the Cardinal Santos Medical Center, Fr. Austriaco said that if more people are vaccinated, “it is difficult for the virus to be transmitted.”
“The question is: What percent of the population needs to be vaccinated? The target threshold for vaccination of a population—when you get containment of Covid-19—is 40 to 50 percent and the attack rate is less than one per 100,000 population. Herd immunity against Covid-19 is 70 to 80 percent and the attack rate is practically zero,” Fr. Austriaco explained.
Containment
Containment, he explained, protects the people against future surges.
“This means, the capacity of future surges will dramatically decrease,” he said but warned that “there would still be outbreaks during containment, clusters of infections but it will not be able to spread widely like what happened in March [here in the country].”
Containment, he added, allows normal gatherings of vaccinated persons without masks and without face shields.
“US is still in containment. US has not yet reached immunity,” he said.
Herd immunity
Fr. Austriaco pointed out that vaccinated person will “protect the unvaccinated person.”
“A herd of vaccinated people protects the unvaccinated from the virus. Herd immunity starves the virus. Herd immunity will turn us to the old normal. Herd immunity will end the pandemic, will restore our lives to near normal,” he said but pointed out the need for high vigilance for “the virus would still be present.”
He said herd immunity should be built in every level of the society – families and individuals, businesses and barangays, cities and municipalities.
“So that we should have 70 percent of herd immunity at every level of society…slowly the different herds will come together. Our hope that eventually, the entire country will be one giant immune herd against Covid-19,” he said.
Population immunity in PHL
In a study Fr. Austriaco collaborated with Allan Paolo L. Almajose of the Department of Chemical Engineering of the University of the Philippines-Diliman, the choice of strategy is both a “scientific and political decision.”
Given that there are two levels of thresholds, the containment and herd immunity, Fr. Austriaco said that according to the target thresholds for vaccination of NCR + (National Capital Region) + eight areas (Batangas, Bulacan, Cavite, Laguna, Pampanga, Rizal, Metro Cebu and Metro Davao) to achieve containment (40 percent to 50 percent) is to have 45 percent of 37 million which is 16.65 million people vaccinated and this is equivalent to 33.3 million doses.
For herd immunity (70 percent to 80 percent), 70 percent of 37 million is 25.9 million or (every adult in NCR+8) 51.8 million doses will be needed.
Duration of inoculation
When asked how long it would take to administer 51.8 million doses in the NCR+8, Fr. Austriaco said that if 100,000 doses are administered per day, it would take 518 days or 17 months; if 200,000 doses per day, 259 days or eight months; if 300,000 doses per day, 173 days or 5.75 months.
“At the rate of 250,000 doses per day, the NCR +8 will achieve containment of Covid-19 sometime in October,” he said.
To reach herd immunity in NCR+8, on the other hand, he said, it would be achieved “before Christmas.”
“We should be vaccinating between 200,000 to 300,000 doses per day from June 1 to November 30, 2021,” he said as he cited that Israel was able to vaccinate most of its adults and “the target should be the same.”