Once the first doses of pandemic influenza a (H1N1) vaccine become available, national health authorities will decide how to implement national vaccination campaigns.

一旦第一剂大流行甲型流感(H1N1)疫苗到位，国家卫生机构就要决定怎样去实施国家疫苗接种活动。

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The very first doses of influenza A (H1N1) vaccine usable to immunize people, from one or more manufacturers, are expected as early as September 2009.

来自一个至数个制造厂家的甲型流感(H1N1)疫苗开始用于接种人群的第一针，预期最早也要到2009年9月。

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Health officials had expected two doses might be needed for H1N1 vaccines, as is the case for young children who receive a seasonal influenza shot for the first time.

卫生部门官员曾经预测人们或许需要接种两支疫苗，类似于儿童首次接种季节性流感时的剂量。

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Newborns need a vaccination within the first day of life to prevent transmission of the virus from their mothers, and babies need two more doses within the first six months for full immunity.

VOA: standard.2010.07.26

If officials decide to produce a vaccine, the first doses would be ready early in the fall.

CNN: Swine flu 'not stoppable,' World Health Organization says

Supplies of flu vaccine have also been ordered and the first doses could be administered in the autumn.

BBC: Tamiflu

However, it would likely take months to produce the first doses.

NPR: Bird Flu 101: How Bad Is The New H7N9 Strain?