The head of the World Health Organization (WHO) has said that while there is hope for a vaccine against Covid-19, one might never be found.
Mr Tedros implored people around the world to comply with measures such as social distancing, hand-washing and mask-wearing, saying: "Do it all."
Globally, more than 18 million Covid-19 infections have been recorded.
The death toll stands at 689,000, with both figures given by the US-based Johns Hopkins University.
Speaking from its headquarters in Geneva, the WHO chief said work on immunisation was progressing.
Meanwhile, the first stage of a WHO investigation into the possible source of the outbreak in China is now complete, he said.