The foreign substance detected in dozens of vials of Moderna's Covid-19 vaccine in Japan is believed to be tiny pieces of metal, according to the country's health ministry. Japan had suspended the use of more than 1.63 million doses of the Moderna vaccine following reports of contamination in the vials.
However, experts have dismissed concerns over significant health problems for those who have been administered the vaccine from those vials, as the chances of the metals entering the body are extremely low. The foreign substances were found in vials at multiple vaccination sites.
On Thursday, Takeda Pharmaceuticals, which distributes the vaccine in Japan for Moderna, said that it had notified the ministry after several vaccination sites reported an unspecified foreign object was found in one specific lot.
The foreign substances were found in as many as 39 vials at eight vaccination sites in the prefectures of Ibaraki, Saitama, Tokyo, Gifu and Aichi since August 16, reports Xinhua news agency. Following that, the health ministry immediately suspended the use of all the Moderna vaccines in the country.
However, the ministry clarified on Friday that the foreign substances are believed to me metals and are a few millimeters in size and don't pose any threat to a person's health. The ministry said that the particles are too small to enter a person's body, so those who have already been jabbed from these vials.
More than 187,000 shots from the three suspended lot had already been administered in at least 21 prefectures, according to a tally by Kyodo News. Those include 50,000 doses in Osaka, 41,500 in Hyogo, 28,020 in Aichi and 13,330 in Hiroshima. This created a lot of panic but any threat to health has now been ruled out.
Moderna too was initially in tension following the revelation. The company along with Rovi and Takeda Pharmaceutical Co. has launched an investigation and according to initial reports the entire thing happened during the production process.
According to Asahi Shimbun, an unidentified senior health ministry official said that the foreign material is "a metal that reacts to a magnet." That said, the ministry also confirmed that so far, there have been no reports of ill health from contaminated doses, or of foreign materials in other batches of the Moderna vaccine that have been distributed in Japan.
Health minister Norihisa Tamura said the government was contacting the 863 workplace and mass vaccination centers that received the three lot numbers to see if they are short of vaccines, and that it would start distributing replacement vials Friday.