TOKYO - Moderna Inc's Covid-19 vaccine contamination woes in Japan widened after two regions put temporary holds on shots following the discovery of foreign substances in more batches.
The disruption to Moderna supplies comes as Japan battles its worst wave of Covid-19 yet, driven by the contagious Delta variant, with new daily infections exceeding 25,000 this month for the first time amid a slow vaccine rollout.
The latest reports of vaccine contamination came from Gunma prefecture near Tokyo and the southern prefecture of Okinawa, prompting temporary holds on Sunday (Aug 29) on shots from two new Moderna lots.
That followed the nationwide suspension of 1.63 million doses last week.
A tiny black substance was found in a Moderna vaccine vial in Gunma, an official from the prefecture said, while in Okinawa, black substances were spotted in syringes and a vial, and pink material was found in a different syringe.
Japan's health ministry said some of the incidents may have been due to needles being incorrectly inserted into vials, breaking off bits of the rubber stopper.
The ministry and Takeda Pharmaceutical, which distributes the Moderna vaccine in Japan, said there were no safety issues from the Okinawa and Gunma incidents and that there was no need for nationwide suspensions.
Gunma and Okinawa can resume using vials from the lots in question as long as they do not contain foreign materials, the ministry told a briefing late on Monday.
The contamination cases come on the heels of a government report on Saturday that two people died after receiving Moderna shots that were among lots later suspended.
The government had said that no safety or efficacy issues had been identified and that the suspension was a precaution.
The causes of death are being investigated.
"It is unlikely, in my opinion, that contamination of foreign substances led directly to sudden deaths," said Takahiro Kinoshita, a physician and vice-chair of Cov-Navi, a vaccine information group.
"If the contaminated substances were dangerous enough to cause death for some people, probably many more people would have suffered from some symptoms after the vaccination.
"However, further investigations are definitely needed to evaluate the harm of the particular doses in question."
"Look at the bigger picture"
Japan earlier halted the use of 1.63 million Moderna doses, shipped to 863 vaccination centres nationwide after Takeda received reports of contaminants in some vials.
Some 500,000 people received shots from those supplies, Taro Kono, the minister in charge of the vaccine push, has said.
Moderna and Spanish pharma company Rovi, which bottles Moderna vaccines for markets other than the United States, said at the time that the contamination could be due to a manufacturing issue in one of Rovi's production lines.
Rovi said, in a statement on Sunday, that an investigation was underway in coordination with Moderna, Takeda and the health authorities.
Takeda also said, on Monday, that the investigation was ongoing.
Rovi shares closed down 13.5 per cent on Monday.
Nicholas Rennick, an Australian doctor practising at the NTT Medical Centre in Tokyo, said the contamination "is a serious problem" and there is a need to investigate, but given rising Covid-19 cases, Moderna vaccinations should "continue with appropriate precautions".
Severe Covid-19 cases are at record levels in Japan, leaving many people to recuperate at home amid a shortage of critical care beds.
Only 44 per cent of its population has been fully vaccinated, lagging vaccination rates of several developed countries.
"We've got thousands of Delta variant patients around Japan as we speak, spreading the virus, and so many of the population remain unvaccinated and unprotected," Rennick said.
"We have to look at the bigger picture."