Govt lab retest confirms presence of polio-2 in Bio-med’s samples
SAMPLES WERE SENT TO CDL KASAULI FOR RETESTING, AFTER BIO-MED CHALLENGED THE RESULTS OF THE INITIAL TESTS BY THE SAME LABORATORY
NEWDELHI: A government laboratory has confirmed the presence of polio-2 virus, a strain that was believed to have been eradicated from India in 2016, in oral vaccine samples made by Bio-med Pvt. Ltd, raising concerns that the contaminated samples may have put children at risk.
Samples of the contaminated batches were sent to the government-run Central Drugs Laboratory (CDL) Kasauli for retesting, after Bio-med challenged the results of the initial tests by the same laboratory.
The report was submitted by CDL Kasauli to the Ghaziabad district court on 15 March. “The samples that were sent for testing following the court order were found to be positive again, which means that the batches had type 2 virus in it,” two people with direct knowledge of the matter said, requesting anonymity.
The contamination endangers the health of those who have not been vaccinated for the polio-2 virus strain, according to public health expert Sylvia Karpagam. “The bigger problem is that the virus can mutate and no one knows into what form— mild or virulent,” Karpagam said. “The contamination endangers many of those who have not received inactivated polio vaccine (IPV) and are exposed to strain 2.”
An email sent to Bio-med did not elicit a response till press time.
Reports about the contamination set alarm bells ringing in September, when traces of polio type 2 virus were found in sewage and stool samples during routine surveillance. Bio-med was found to be supplying polio vaccines for the government-run immunization programme.
On September 27, the Drug Controller General of India asked Bio-med to explain how the eradicated polio-2 strain found its way into vaccine vials. Around 50,000 vials—one vial has 20 doses— of contaminated vaccine were believed to have been used in Uttar Pradesh and Telangana. The company was thereafter barred from manufacturing and supplying vaccines.