KP.2 variant emerges as a new concern in Hong Kong’s ongoing COVID-19 surveillance

Professor Ivan Hung

17th May 2024 -(Hong Kong) The Centre for Health Protection has noted a consistent level of COVID-19 activity, similar to previous weeks. The dominant strains currently circulating are JN.1 and its derivatives, which account for 98.8% of analysed samples. Among these, a newer lineage, KP.2, has been detected in approximately 15% of wastewater samples. The World Health Organization is now monitoring KP.2, a descendant of JN.1, although there is no current evidence to suggest that KP.2 or JN.1 cause more severe disease than the XBB lineage and its derivatives.

Professor Ivan Hung, Chair Professor at the University of Hong Kong’s Department of Medicine and Chief of Infectious Diseases, provided insights into the characteristics of KP.2. The strain shows high transmissibility and possesses immune evasion capabilities, though its pathogenicity is not considered particularly severe. According to data from the US Centers for Disease Control and Prevention (CDC), KP.2 now accounts for 28.2% of COVID-19 infections in the United States, a significant increase from just 1.4% in mid-March. Experts believe KP.2 may be more transmissible than JN.1, potentially leading to an uptick in cases over the summer.

The Centre for Health Protection also reported a decrease in COVID-19 outbreaks in educational and residential institutions. From May 5 to May 11, there were 11 reported outbreaks affecting 66 individuals, down from 17 outbreaks and 126 affected individuals the previous week. Between May 12 and May 15, two outbreaks were recorded, impacting 10 people.

In addition to monitoring COVID-19, the Centre is also keeping a close eye on seasonal influenza, which continues to rise and remains at a high level of activity. During the week of 5th to 11th May, the rate of flu-like illnesses reported by designated outpatient clinics was 14.8 cases per thousand consultations, an increase from 14.1 cases the previous week. In private clinics, the reported rate was significantly higher at 78.9 cases per thousand consultations, up from 61.2 cases.

This continued prevalence of both COVID-19 and influenza highlights the ongoing challenge faced by public health officials and the medical community in managing respiratory diseases. The situation underscores the need for continued vigilance and adaptation of strategies to prevent the spread of these infections, particularly in densely populated areas like Hong Kong.