A facemask marketed as a highly preventative measure against contracting H1N1 is a dud, the top drug authority announced yesterday.

The privately owned Tianjin Mingda Science and Technology R&D Company behind the mask has been shut down because health authorities never gave consent for the company to manufacture the masks for medical use, said State Food and Drug Administration spokeswoman Yan Jiangying yesterday.

The invention, which made claims that any wearer would not contract the H1N1 flu, made local headlines Monday as the number of cases of the potentially lethal infection rises and vaccines are limited in the country.