Asia is seeing an “epidemic of counterfeits” of life-saving drugs, experts say, and the problem is spreading. Malaria medicines have been particularly hard hit; in a recent sampling in Southeast Asia, 53 percent of the antimalarials bought were fakes.

Bogus antibiotics, tuberculosis drugs, AIDS drugs and even meningitis vaccines have also been found.

Estimates of the deaths caused by fakes run from tens of thousands a year to 200,000 or more. The World Health Organization has estimated that a fifth of the one million annual deaths from malaria would be prevented if all medicines for it were genuine and taken properly.

“The impact on people’s lives behind these figures is devastating,” said Dr. Howard A. Zucker, the organization’s chief of health technology and pharmaceuticals.