World Health Organization (WHO) warned on Monday.“The message to people and governments is clear: ‘Do it all’," Tedros Adhanom Ghebreyesus said at a virtual news briefing from the UN body’s headquarters in Geneva.“We know from serology studies that most people remain susceptible to this virus, even in areas that have experienced severe outbreaks," he said, adding that over the past week several countries that looked as though they were past the worst are now having to contend with fresh spikes in cases.“A number of vaccines are now in phase three clinical trials and we all hope to have a number of effective vaccines that can help prevent people from infection," said Ghebreyesus.“However, there’s no silver bullet at the moment and there.