A new wave of COVID-19 is emerging in parts of Asia, prompting increased vigilance among health authorities worldwide. Singapore, Hong Kong, China, and Thailand have all reported a rise in new cases, primarily driven by the spread of new Omicron subvariants, particularly JN.1 and its related strains. This situation is being closely monitored to mitigate potential risks.

Singapore has seen a sharp increase in daily COVID-19 cases, exceeding 14,000 in early May 2025, up from 11,100 in late April. Hospitalizations have also increased, although ICU cases have slightly decreased. Authorities emphasize that current evidence does not suggest these variants are more contagious or cause more severe illness than previous strains. Experts attribute the rise in infections partly to waning immunity within populations and anticipate recurring waves of COVID-19.

Currently, the predominant variants circulating are LF.7 and NB.1.8, both descendants of JN.1, accounting for over two-thirds of sequenced cases. In contrast, India has not experienced a significant surge in COVID-19 cases, with only 93 active cases reported as of May 19, 2025, according to the Ministry of Health and Family Welfare. Some physicians in Mumbai have noted a slight increase in mild cases, primarily among younger individuals, but health officials maintain that there is no indication of a new wave and advise continued caution, especially given the surges in neighboring countries.

The JN.1 variant, a lineage of the Omicron BA.2.86 variant first identified in August 2023, was designated as a Variant of Interest by the World Health Organization (WHO) in December 2023. This variant has approximately 30 mutations, more than any other variant at the time, which enhance its ability to evade the immune system. While BA.2.86 did not become dominant in 2023, JN.1, with one or two additional mutations, has proven more successful at spreading while retaining the immune-evasion properties of its parent.

According to Johns Hopkins University, JN.1 is now the most prevalent variant globally. In the 12th epidemiological week of 2025, JN.1 accounted for 93.9% of cases in the Western Pacific region, 85.7% in Southeast Asia, 94.7% in Europe, and 93.2% in the Americas.

Research indicates that JN.1 is more challenging for the immune system to combat. Vaccinated individuals or those with prior infection have fewer antibodies capable of neutralizing JN.1 compared to previous variants, indicating partial immune escape. However, the XBB.1.5 monovalent booster, designed to protect against the XBB.1.5 Omicron subvariant, helps bolster protection against JN.1. The WHO states that this booster increases antibody levels, providing 19% to 49% protection against symptomatic infection from JN.1, according to studies in the United States.

Multiple XBB.1.5 monovalent vaccines have been deployed worldwide, including the Pfizer-BioNTech Comirnaty and Moderna Spikevax (mRNA vaccines approved in the US, EU, Canada, and Australia), Novavax’s Nuvaxovid (protein subunit vaccine approved in the EU), and Zapomeran (Kostaive), a self-amplifying mRNA vaccine approved in Japan and the EU. In India, the Covovax XBB.1.5 monovalent booster remains the only COVID-19 vaccine specifically tailored to address the Omicron XBB.1.5 subvariant.

Symptoms of JN.1 infection are similar to those of other COVID-19 variants, including sore throat, fever, runny or stuffy nose, dry cough, fatigue, headache, loss of taste or smell, muscle pain, conjunctivitis, diarrhea, and vomiting. Some patients may experience more severe fatigue, and shortness of breath remains a critical symptom requiring immediate medical attention. Health authorities urge continued vigilance, vaccination, and attention to potential symptoms as new variants continue to emerge.

While JN.1 is more contagious than previous COVID-19 variants, it does not typically lead to more severe disease. Most infected individuals experience mild to moderate symptoms, such as sore throat, fever, and cough. Severe cases are uncommon, and hospitalization rates have not been significantly impacted. Death rates associated with JN.1 remain lower than in earlier COVID-19 waves, suggesting a decreased overall severity. Vaccines and boosters continue to offer effective protection against severe illness, making continued vaccination crucial for minimizing risk and controlling transmission.