Health officials worry as untraceable virus clusters emerge

A woman wearing a protective facemask amid fears about the spread of the Covid-19 walking past a mosque in Singapore. In S. Korea, Singapore and Iran, clusters of infections are leading to a jump in cases of the new viral illness outside China. But it’s not the numbers that are worrying experts: It's that increasingly they can't trace where the clusters started. - AP

BEIJING/SEOUL/SINGAPORE: In South Korea, Singapore and Iran, clusters of infections are leading to a jump in cases of the new viral illness outside China. But it’s not the numbers that are worrying experts: It's that increasingly they can't trace where the clusters started.

World Health Organisation (WHO) officials said China's crackdown on parts of the country bought time for the rest of the world to prepare for the new virus.