Omicron vs. Delta: How do the two COVID-19 variants differ?
Last year, the Philippines saw a surge in COVID-19 cases due to the Delta variant. This 2022, daily infections in the country are increasing again, and local health officials are saying it's due to the Omicron strain.
As of Jan. 11, a total of 43 Omicron cases have been detected, but according to the Philippine Genome Center (PGC), Delta remains the most dominant strain in the country. PGC is currently undergoing more genome sequencing to see a clearer picture of the situation.
But how do the two strains differ from each other? Which one is more transmissible? Do infected people show the same symptoms? Here's what you need to know about the Omicron and Delta variants.
Spread
According to the World Health Organization (WHO), Omicron is more transmissible than the Delta variant. Recent studies from scientists in Japan and France also say this. Since its first detection in South Africa, the Omicron variant has spread across the globe, causing surges in cases in different countries like the United States where it's currently the most dominant strain.
Genome sequencing has also revealed that Omicron is highly mutated with over 30 mutations in the spike protein than Delta's 18 mutations. This makes the newer variant immune to vaccine-induced antibodies, causing more breakthrough infections.
Symptoms
Symptoms linked to the Omicron variant have been described as mild compared to other strains. People infected with the variant experience sore throat, nasal congestion, dry cough, and muscle pain. Fewer individuals report loss of taste and sense of smell, but some have nausea and gastrointestinal issues.
Meanwhile, a Delta case comes with symptoms similar to the Alpha COVID-19 variant such as headache, sore throat, runny nose, fever, shortness of breath, chills, fatigue, and loss of smell.
While it typically takes about five or six days—four for Delta—before an infected individual experiences symptoms, it only takes three days for symptoms to kick in when you're infected with the Omicron variant.
A study from the University of Cambridge also found that Omicron has a hard time infecting lung cells.
"The fact that Omicron is not so good at entering lung cells and that it causes fewer fused cells with lower infection levels in the lab suggests this new variant may cause less severe lung-associated disease," said virologist Dr. Ravi Gupta.
However, as the Department of Health (DOH) noted, you can't tell whether you have Omicron, Delta, or just a flu by symptoms alone. It's best to get tested once you experience any symptoms to confirm if you have COVID-19.
In addition, you can't tell which variant of COVID-19 you have—if you're infected—unless your RT-PCR test is sequenced.
Can you still get infected after recovering?
Some experts say that those who recover from Omicron may get boosted defenses against any form of COVID-19. A South African study, which hasn't been peer-reviewed, also found that those infected with Omicron—particularly those who were vaccinated—developed enhanced immunity to Delta.
With Delta, available data suggests you can still contract Omicron after recovering.
How to stay safe
To keep yourself safe from the virus, opt for better face masks, disinfect and wash your hands often, practice physical distancing, and get a booster shot if you're already vaccinated.