MANILA, Philippines – After weeks of decline, coronavirus cases in the Philippines are slowly increasing again with average daily infections over the past week hovering close to some 200 new cases per day. Experts are watching data closely to see if this increase will be sustained. 

Over a year into the country’s vaccination drive, roughly 63% of all Filipinos have been fully vaccinated. Here’s what we’re watching this week of May 29, 2022: 

Vaccines for little kids

Pfizer recently announced that it would seek authorization from the United States Food and Drug Administration (FDA) for its vaccine for children under 5 years old to at least 6 months old, after a study of administering a third dose was found to improve the vaccine’s efficacy. 

• The US FDA’s expert panel is expected to meet on the matter on June 15, when it will review data from Pfizer for the three-dose regimen and Moderna for a two-dose regimen. 
• Pfizer reported that its three-dose regimen induced a strong immune response, was well tolerated among the group, and was 80.3% effective at preventing infection at a time when the Omicron variant was circulating.
  • For this group of children under the age of 5, the dosage used is one-tenth of the dose used for adults. The first two doses are given 21 days apart, while the third dose is given at least two months after the second shot. 
  • STAT News summarizes the findings: “The Phase 2/3 trial was conducted in 1,678 children. A month after receipt of the third dose, antibody titers from a subset of the children were compared to those seen in people aged 16 to 25 years after they had received two doses of the vaccine. The antibody levels were “non-inferior” in children ages 6 to 24 months, and also among those children ages 2 to 4 years old.” 
• The development picks up from early February, when health authorities were expected to tackle vaccine data for kids at least 6 months to 4 years old, with the goal of granting emergency approval. The FDA held off on the meeting to study the possibility of offering a third dose for the group. 
  • While Pfizer is requesting emergency authorization for a three-dose regimen, Moderna completed a submission for a two-dose regimen. Moderna said it would study the effect of a booster in this age group, but no data has been released as of the moment. 
• Both in the US and in the Philippines, little kids in this age bracket are the only group that cannot get vaccinated yet. An approval by the US FDA will pave the way for one with the Philippines’ FDA, which only accepts vaccine applications for vaccines or drugs that have been granted emergency approval in their respective countries or mature and established FDAs, like that of the US.  

A new surge on the way?

Against the backdrop of more Omicron subvariants detected in the Philippines, COVID-19 infections appeared to be on the rise again after daily new cases in the recent week grew for the first time in months. More data expected in the coming days could tell us if the country could be facing the start of a new surge. 

• Cases already registered an increase in the recent week, after the health department’s weekly bulletin last Monday, May 23, indicated an uptick. But epidemiologist Dr. John Wong said data from the rest of the week would help in determining if the increase is sustained or if these were random increases in cases. 
• How high cases could go in the coming weeks will depend on the following factors: “Variant, vaccination level, masking and distancing behavior, ventilation, and weather,” Wong said. 
  • Right now, factors conducive to an increase are present: More transmissible subvariants of Omicron are present, vaccination now (63%) is only slightly higher than in January (53%), the rainy season will bring more people indoors where ventilation and behavior is hard to measure, and some immunity from prior infection during the January wave has started to wane. 
• Back in April, the Department of Health warned of a possible surge taking place as early as mid-May – if Filipinos would continue to let their guard down against the virus. At the time, the DOH already flagged decreased compliance in observing minimum health standards. Projections back then showed a surge in cases could even surpass the peak in cases seen during the recent Omicron wave.
• The good news is, there are still actions we can take. 
  • What individuals can do: Wear well-fitting masks, isolate when sick, get vaccinated and boosted when eligible, ensure good airflow.
  • What hospitals can do: Prepare surge capacity. 
  • What the government can do: Reinvigorate its vaccination program, enforce indoor ventilation standards, remind the public to observe public health standards. 

Comparing Omircon subvariants

Since its emergence in the global landscape in late 2021, Omicron and its subvariants have remained in the spotlight. Scientists are studying the variant and its different forms after data has shown their ability to fuel several surges and evade antibodies from vaccines and previous infections. 

Here’s a quick rundown on what data so far shows about the Omicron family: 

• Trevor Bedford, a computational biologist at the Fred Hutchinson Cancer Research Center, summarized in a recent Twitter thread what US data is showing about the fitness of BA.4, BA.5, and BA.2.12.1 subvaraints:
  • Citing data, Bedford said it “suggests BA.4 and BA.5 are fitter than BA.2.12.1 as one might expect given the additional spike F486V mutation (plus mutations elsewhere in the genome), and that we expect BA.4 and BA.5 to continue to increase in frequency on the background of BA.2 and BA.2.12.1.”
  • In the US, he added, “We expect at least some portion of the BA.4 / BA.5 epidemics to be driven by increased vaccine breakthrough and increased reinfection relative to current BA.2 circulation.”
• Eric Topol, director of the Scripps Research Translational Institute, also breaks down some preliminary studies on Omicron subvariants, including that BA.2.12.1 and BA.4/BA.5 appear to have “enhanced replication in lung cells compared with BA.2”

• Trisha Greenhalgh, a member of the independent Scientific Advisory Group for Emergencies, on what this means: “Bottom line: the pandemic is not over, and it’s NOT getting milder.”

– Rappler.com