Jakarta. The government has pledged to accelerate the delivery of booster vaccine doses to Indonesia's most vulnerable population as it expected a new Covid-19 wave, driven by new Omicron subvariants, would spike in the next six weeks.  

Minister of Health Budi Gunadi Sadikin Monday said the order to increase the vaccination effort came directly from President Joko "Jokowi" Widodo. Among the measures is a mandatory third dose vaccination for attending public gatherings, Budi said.    

The order came after the country detected Omicron BA.4 and BA.5, the virus's latest subvariants with the higher transmissibility that can infect fully vaccinated individuals.

"Our observations are that the BA.4 and BA.5 waves usually peak one month after the discovery of the first case," Budi said during a press conference on Monday. 

"The second and third week of July 2022 should see the peak of cases from the transmission of BA.4 and BA.5," Budi said.  

Since last month, Indonesia has found eight Covid-19 cases with Omicron subvariants BA.4 and BA.5.

Budi said that in Indonesia, eight cases of Covid-19 Omicron subvariants BA.4 and BA.5 have been found. Three were imported cases involving Mauritius, the United States, and Brazil nationals who came to Bali for the Global Platform for Disaster Risk Reduction (GPDRR) Forum event last month. The other 5 cases were local transmission in Jakarta, Budi said.

The minister expects an increase in booster vaccination rate should be enough to keep the subvariants spread at bay. "People who have been vaccinated with the third dose have immunity for six months," he said. 

Only 47.7 million, or 23 percent, out of 208.2 million eligible Indonesians have received their third vaccine doses against Covid-19. That compared to 168.1 million, or 81 percent, who had their second dose shot. 

The number of people who already have antibodies to SARS-CoV-2, the virus that causes Covid-19, is much higher. A government serology survey in March found that 99 percent of the population already got the antibodies, either from vaccination or natural infections.

Still, epidemiologists warned that the BA.4 and BA.5 subvariants could cause breakthrough infections and spread like wildfire in fully vaccinated populations.

Dicky Budiman, an epidemiologist from the Center for Environmental and Population Health at Griffith University Australia, said the subvariants came with mutations in their L452 gene, like the highly contagious Delta variant. 

"It makes them, especially Omicron BA.5, very easy to infect people," Dicky told the Globe's sister publication BeritaSatu.com on Sunday. 

"Even people who have been infected by Omicron BA.1, BA.2, and BA.3 can still be infected again by this BA.4 or BA.5. That's the ability of BA.4 and BA5. They can reinfect," Dicky said.

He recommended the government vaccinate at least 50 percent of the eligible population with the third dose by the end of this year. 

He also called for the public to remain disciplined in carrying out health protocols; wearing masks, maintaining safe distances, and washing hands.

"If the mitigation is sub-optimal, there could be potential increases or new waves. Masks are important. Hand washing and other health protocols are still important to reduce the spread," Dicky said. 

However, Minister Budi said the government refrains from reinstating the mask mandate in open spaces. 

"We can still not wear them outside. But if there is a crowd or someone is coughing, or we ourselves feel unwell, please wear a mask," Budi said. He added that it is still recommended to wear a mask for situations in rooms with an air conditioner (AC) with a closed circulation.

Also, the government noted BA.4 or BA.5 subvariant causes fewer deaths and hospitalizations than the previous Omicron subvariants. 

The subvariants' hospitalization rate is only a third of the previous Omicron subvariants, while the death rate was only a tenth of the last wave, Budi said. 

"So even though BA.4 and BA.5 have caused an increase in cases in several countries in the world, the peak in hospitalizations and deaths is much lower than the initial Omicron variants," said Minister of Health Budi.