Vaccine raises spectre of 'dead' polio strain's spread

​Some batches of oral polio vaccine manufactured by Biomed have been found to be contaminated with polio type 2 virus. The government has ordered a probe to find out how the type 2 strain was retained even after all manufacturers were ordered to take measures for complete destruction of all traces of Polio Virus Type 2 by 25 April, 2016.

from India News | Latest News Headlines & Live Updates from India - Times of India