COVID-19 Cases Rise In Asia: Symptoms Of JN.1 Variant And What Sets It Apart From Other Coronavirus Strains

After three years of ongoing battle with SARS-CoV-2 from 2020 to 2023, COVID-19 is sweeping across parts of Asia, a development that warrants cautious attention.

Health officials in several Asian countries, including Hong Kong, Singapore, China, and Thailand, have reported a significant rise in new infections, largely attributed to the spread of emerging Omicron subvariants such as JN.1 and its descendant variant LF.7 and NB.1.8.

Also read: New COVID-19 Wave Sweeps Across Asia, Hitting Hong Kong And Singapore Hard: What You Should Know

According to reports, the Lion City has experienced a sharp rise in COVID-19 cases, with infections surpassing 14,000 in early May 2025, compared to 11,100 in the last week of April.

Singapore’s Health Ministry has also acknowledged that the current rise in cases is largely due to waning immunity.

What is the JN.1 variant?

Although the original strain of COVID-19 is no longer in circulation, in April 2024, the World Health Organization (WHO) labelled SARS-CoV-2's variant JN.1 as one of the most prevalent globally. 

JN.1 virus can trace its lineage back to Omicron BA.2.86, which was identified in August 2023. The variant features 30 mutations evading immunity.

According to Yale Medicine, “A difference between BA.2.86 and JN.1 is that the latter has one mutation in its spike protein, a single change that may or may not alter any of the traits that characterize the virus, although preliminary research shows that it may provide extra immune evasion.”

Symptoms of the JN.1 variant

The JN.1 variant of COVID-19 has similar signs to other Omicron variants. Here are some major symptoms outlined by Ada Health:

• Fever
• Dry/non-productive cough
• Shortness of breath/difficulty in breathing
• Feeling fatigued
• Sore throat
• Headache
• Muscle or body aches
• Congestion or a runny nose

What sets the JN.1 variant apart from other SARS-CoV-2 strains?

“Viruses such as SARS-CoV-2 evolve over time due to changes in their genetic code brought about by viral recombination or mutations during genome replication. This evolution has resulted in novel variants that differ significantly from the original strain,” states the National Institute of Health (NIH).

“The spike protein of JN.1 has accumulated over 30 mutations, a surface protein of SARS-CoV-2 that facilitates attachment, with the addition of a novel mutation, L455S.”