H1N1流感疫苗紧急召回(有声)

美国市场上的80万支甲型H1N1流感疫苗12月15日被宣布召回，原因是其药效发生了弱化。

美国疾病控制与预防中心表示，那些疫苗是在11月份上市的，并且大都已经被接种，是法国赛诺菲巴斯德公司专门为半岁至3岁儿童研制并生产的。该中心与生产厂家均强调，召回的原因不是因为该疫苗存在安全隐患，而是因为它的药效已不如刚出厂时那么明显。

ROBERT SIEGEL, host:

From NPR News, this is ALL THINGS CONSIDERED. I'm Robert Siegel.

MELISSA BLOCK, host:

And I'm Melissa Block.

A recall has been issued for 800,000 doses of the H1N1 swine flu vaccine. The recall comes from one of the vaccine manufacturers after it was learned that the shots had lost some of their potency.

As NPR's Joanne Silberner reports, government officials say the recall does not raise safety concerns.

JOANNE SILBERNER: The vaccinations were in preloaded syringes intended for children from six months to three years old. Anne Schuchat, head of the immunization division at the Centers for Disease Control and Prevention, says parents have nothing to worry about.

Ms. ANNE SCHUCHAT (Director, Centers For Disease Control And Prevention): This is not safety related and does not have clinical implications. So, parents can be reassured that if their children got vaccinated with a dose from this a lot they should be just fine.

SILBERNER: What happened was this: Sanofi Pasteur, one of five manufacturers ran some test on vaccine samples from lots that had already been distributed. Dr. Michael Decker is with Sanofi.

Dr. MICHAEL DECKER (Sanofi Pasteur): And as a part of this routine testing program, we found that certain lots of the H1N1 pandemic vaccine had lost potency falling below the preset minimum level.

SILBERNER: Recalls like this happen occasionally with vaccines, says the CDC's Schuchat.

Ms. SCHUCHAT: We had a recall last spring with the seasonal flu vaccine. This happens from time to time, year to year. It usually doesn't get as much notice of course but these things occur.

SILBERNER: The potency drop was only 6 to 12 percent, there was enough vaccine in each shot still be effective says Schuchat.

Ms. SCHUCHAT: Children won't have to be brought back in to be revaccinated because of this lot problem. Instead, we just want parents to remember that if their children haven't already gotten two doses about one month apart, they should make sure that their young child gets the second dose.

SILBERNER: Vaccine expert William Schaffner of Vanderbilt University says catching a dip in potency is a measure of how carefully vaccines are checked. He says that's the good news. And the bad news is that the recall make turn some people away from vaccination. There are already those who object to vaccines on the first place. And now

Dr. WILLIAM SCHAFFNER (Chairman, Vanderbilt University Department of Preventive Medicine): Vaccine has to be withdrawn and we're between the holidays now. People are not so interested in vaccination. This may drive their interest even lower.

SILBERNER: So far the government has distributed 95 million doses of vaccine to states for distribution. The 800,000 recalled vaccines are one percent of Sanofi's output. The rest is unaffected by the recall, as are the vaccines made by four other manufacturers.

Joanne Silberner, NPR News.