The national government is facing a "big challenge" in its immunization program against the coronavirus disease (COVID-19) as it targets to inoculate 77.75 million Filipinos before the end of 2021.

To achieve herd immunity by year-end, the national government needs to vaccinate 77,746,906 Filipinos which comprised 70 percent of the country's 111,067,008 total population, said vaccine czar Carlito Galvez Jr. on Monday night, July 12.

"Sa talaan po ng Philippine population based on UN, ang total nating population is 111,067,008 people. So 'yung magiging basehan po natin ng ating total target population for vaccination is 77,746,906 (According to the tally of the Philippine population based on UN, our total population is 111,067,008. The bases of our total target population for vaccination is 77,746,906)," Galvez said at President Duterte's public address.

As of July 11, the government has administered 13,196,282 million doses.

However, of these data, only 3,526,342 Filipinos are deemed fully-vaccinated after receiving two doses of COVID-19 vaccine. This represents 4.54 percent of the total population, Galvez said.

On the other hand, a total of 9,669,940 Filipinos (12.44 percent) received their first dose of vaccine.

"Napakalaki po ng atin pong challenge na makuha 'yung herd immunity by the end of the year (We are facing a big challenge in achieving herd immunity by the end of the year)," Galvez said.

At present, the country has a total vaccine supply of 20,779,910 doses.