Geneva, June 23 (RHC)-- Many countries that have been successful in tackling the novel coronavirus are seeing an increase in cases due to religious events and other vulnerable settings like expatriate gatherings, the World Health Organization's Maria Van Kerkhove said.

"Any opportunity that the virus has to take hold, it will. It is really important that countries are in a position to rapidly detect these cases," she told an online briefing.

The WHO's Mike Ryan said that there seemed to be new clusters in South Korea linked to clubs, shelters and amusement parks and that waste water findings in northern Italy showed there was a chance the virus was circulating there before anyone had realised.