The SAR government, however, insisted that its 300,000 vaccines would be enough to deal with the most vulnerable patients among the poor, sick and elderly.

Secretary for Health, Welfare and Food York Chow Yat-ngok said the government had told private sector doctors to order their supplies of the vaccine well in advance.

However, the Hong Kong Medical Association warned that owing to a worldwide shortage, ordering the vaccines in advance is no guarantee of delivery.

It said that doctors had been told by manufacturers they could deliver only between 25 and 50 per cent of the supplies that had been ordered.

The association also said the prices of some vaccines had doubled compared to last year.

Association president Choi Kin said even the government's supply of vaccines might not be enough to meet the demand and urged the Department of Health to find other sources of supply.