GENEVA : The head of the World Health Organization says more than 100,000 confirmed cases of coronavirus have been reported worldwide each day over the past two weeks - mostly in the Americas and South Asia - and countries that have curbed transmissions “must stay alert to the possibility of resurgence."Tedros Adhanom Ghebreyesus noted a new cluster of cases in Beijing, which went more than 50 days without a new case of COVID-19, and said the origin of that new series of cases is under investigation.Dr.