The U.S. Centers for Disease Control and Prevention (CDC) has started working on a vaccine for the avian influenza A (H7N9) now gripping China, which has so far claimed five lives on Thursday. The number of people infected have likewise risen to 14 cases.

The CDC said it has started making a "seed" virus based on genetic sequence information on the strain. The seed virus may be available within the next few weeks and may already be used to create a vaccine by manufacturers. However, mass production of a vaccine against the new avian influenza A (H7N9) strain could take five to six months.

Moreover, the CDC stressed the measures it currently undertaking were part of the routinary standard operating procedures when a new flu virus is detected in people.

But "right now there is no evidence to suggest that is the case," Tom Skinner, CDC spokesman, told Reuters.

On Thursday, Shanghai began the process of culling poultry in one of its markets, as the country's Ministry of Agriculture said the new avian influenza A (H7N9) has been traced to have emanated from pigeon samples collected at the Huhuai wholesale agricultural market, also in Shanghai.

Poultry trading areas in two other markets were likewise ordered closed after separate samples showed evidence of the virus.

Meanwhile, immediate neighbor countries Japan, Hong Kong and Vietnam have taken respective measures to combat the possible entry of the new avian influenza A (H7N9) virus into their respective territories.

Posters have been put up in entry points at airports in Japan telling travelers from China to seek immediate medical attention if they suspect they have bird flu. Hong Kong had likewise took the same measure.

Vietnam ordered the temporary suspension of Chinese poultry imports.

Beijing vowed to openly communicate details of the new strain not only to its citizens but also to its global audience. The Chinese government have been criticised for its apparent slow response to the outbreak, thus generating suspicions of a cover-up.

China "will continue to openly and transparently maintain communication and information channels with the World Health Organization and relevant countries and regions, and strengthen monitoring and preventative measures", the Health Ministry said in a statement.

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China Bird Flu Pandemic: Deaths Now at 3, Number of Infected Rises to 9, Virus Could Transfer from Poultry to Other Mammals

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