Japan's coronavirus inoculation campaign has been progressing slowly, with over 99 percent of the population yet to receive a shot about two months after its start, trailing many developed nations.

Japan, which currently completely depends on imports for its coronavirus vaccine supply, began inoculating about 36 million seniors aged 65 or older on Monday after beginning its campaign with health care workers on Feb. 17. The elderly account for around 29 percent of Japan's population.

Out of Japan's 4.8 million healthcare workers, about 1.1 million -- equivalent to about 0.87 percent of the population -- had received at least one dose as of Friday, according to the Health, Labor and Welfare Ministry.

Some advanced nations are way ahead of Japan in terms of COVID-19 vaccinations, according to data gathered by researchers at the University of Oxford.

Our World in Data, produced by a research team based at the university, showed that over 61 percent of the population in Israel had received at least one vaccine dose as of April 8, while the rate stood at 47 percent in Britain, around 34 percent in the United States, and around 15 percent in Germany.

Multiple factors are believed to be behind the slow progress of the vaccination program in Japan, where domestic makers have been slow in their efforts to develop coronavirus vaccines.

Among the reasons is that Japanese authorities only gave their first approval to a vaccine -- the one developed by U.S. pharmaceutical giant Pfizer Inc. -- about two months after Europe and the United States did so, according to critics.

An additional factor is that Japan currently relies exclusively on the European Union for shipments of the Pfizer vaccine, and EU approval is needed for each shipment.

In Japan, public concern over potential side effects from coronavirus vaccines remains relatively high, and Japan's government implements strict requirements for vaccines, including mandatory additional clinical trials on its own population.

Some health experts have tried to add a positive twist to Japan's trailing behind other countries, saying it would allow Japan to "assess the situation regarding side effects overseas."

Others, though, warn that the fact that Japan has seen significantly fewer infections and COVID-19 deaths than in many European countries and the United States may have led to a lack of urgency over vaccines -- one that may see it lose out in the international competition to secure supply.

Cumulative coronavirus infections surpassed 500,000 on Friday in Japan.

Taro Kono, the minister in charge of vaccination efforts, has said the government is poised to distribute a total of 100 million doses, enough to fully vaccinate 50 million people, by late June.

The Pfizer vaccine, the only vaccine approved in Japan so far, is a double-dose vaccine with people set to take their second shot usually three weeks after the first shot.

In the meantime, municipalities have voiced their concerns over a series of schedule changes by the central government.

==Kyodo

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