A senior Chinese official told Reuters that the country is confident that it can control an outbreak of H7N9, just as the WHO announced that were now 21 human cases with six deaths. China is reported to be mobilizing resources nationwide to combat the new strain, monitoring hundreds of close contacts of confirmed cases and culling tens of thousands of birds where traces of the virus were found.

Also on Sunday WHO said more than 530 close contacts of the 21 people now listed as confirmed cases are being closely monitored for any signs of similar disease and at this time there is no evidence of ongoing human-to-human transmission.

The bird flu outbreak has caused global concern and some Chinese internet users and newspapers have questioned why it took so long for the government to announce the new cases, especially as two of the victims fell ill in February. The government has said it needed time to correctly identify the virus.

Many of us of course recall the SARS outbreak in 2003 when Chinese authorities initially tried to cover up the outbreak when it emerged in China.  SARS ultimately killed about 10 percent of the 8,000 people it infected worldwide.