False claims and misinformation about vaccines on social media are undermining young people's trust in COVID-19 vaccines in Japan, imperiling the government's efforts to finish large-scale inoculations by November as it pursues herd immunity.

Myths such as "vaccination causes infertility" and "coronavirus vaccines using messenger RNA change your DNA" have been widely spread, and anti-vaccination posts are rampant on Facebook and Twitter.

"There is absolutely no scientific evidence that the coronavirus vaccines will cause infertility," Taro Kono, the minister in charge of Japan's inoculation effort, said on his blog last month.

He said "vaccine hoaxes" have been spreading around the world and Japan is no exception. He urged the public to be wary of disinformation.

Preparation is under way for coronavirus vaccinations at Hiroshima University on June 21, 2021, in Higashihiroshima in Hiroshima Prefecture, western Japan. Mass vaccinations at some Japanese universities for their students and employees began the same day. (Kyodo) ==Kyodo

The American College of Obstetricians and Gynecologists "recommends that pregnant individuals have access to COVID-19 vaccines" and that "claims linking COVID-19 vaccines to infertility are unfounded and have no scientific evidence supporting them."

The Japan Association of Obstetricians and Gynecologists as well as the Japan Society for Infectious Diseases in Obstetrics and Gynecology also say the advantages of COVID-19 vaccination outweigh the disadvantages for pregnant women. The Japanese health ministry says there have been no reports of coronavirus vaccines affecting reproductive functions.

Kono's blog is overseen by a group of some 30 doctors and experts who founded a project called "COV-Navi" with an aim of providing comprehensible information on the efficacy and side effects of coronavirus vaccines.

"In the past few weeks, we have been receiving a lot of questions from people regarding false information about vaccines," said Tomoya Kurokawa, a doctor at Chiba University Hospital who also administers COV-Navi.

When vaccinations started at workplaces and universities in late June, more people looked up vaccination information online and came across hoaxes that fueled anxiety, Kurokawa said.

"Many young people are hesitant toward getting vaccinated because they think they will not fall seriously ill from COVID-19, thinking there's no point of inoculation," Kurokawa said, but warned the disease could cause long-term effects for people of all ages.

In a recent survey by Kyushu Bunka Gakuen, which operates private schools and universities in southwestern Japan prefecture of Nagasaki, a total of 388, or 45.9 percent, of the 846 high school students consulted said they would be vaccinated "if it is compulsory."

Meanwhile, 110 students, or 13.0 percent, said they would prefer not to get vaccinated.

The survey, conducted in early June, also showed 137 students, or 16.2 percent, said they would get inoculated while 34, or 4.1 percent, responded they would "never" get vaccinated.

Among the reasons for not wanting the vaccination, 59.1 percent of those who were against getting a shot cited "a fear of side effects," followed by "questionable" effectiveness of vaccines at 13.4 percent.

A spokesman for the school said, "Perhaps, conflicting information from the internet and people around (the students) is increasing their sense of insecurity (about vaccination)."

People wearing masks walk in Tokyo's Shibuya district on July 14, 2021, as the Japanese capital reports 1,149 daily coronavirus cases, topping 1,000 for the first time since May 13. (Kyodo) ==Kyodo

The governor of Tokyo, where a fresh state of emergency has been recently been declared and the highest cumulative number of coronavirus cases has been reported in Japan, also expressed concerns.

Tokyo Gov. Yuriko Koike said in a regular press conference last week both correct and incorrect information has been circulating on social media and that "the diffusion of the correct knowledge about vaccines" is necessary among young people to speed up the inoculation program.

Japan has recently been accelerating its vaccine rollout, extending the program to younger people after starting with health care workers and people aged 65 or older.

In a separate survey of about 11,800 people by a state-backed institute, 80.6 percent of the respondents aged 65 or older said they plan to get inoculated, while about 17.5 percent of those aged between 18 and 29 said they plan not to get vaccinated, according to the Research Institute of Economy, Trade and Industry.

The survey, which was conducted over three periods from October 2020 with the latest round carried finishing in May this year, showed that younger age groups are tending to be less open to vaccination.

"Promoting vaccination across all generations will require finding ways to motivate younger people to get vaccinated," RIETI researchers wrote.

Chiba University Hospital's Kurokawa said, "It is important to make a decision on whether to get vaccinated after having understood the correct information about vaccines."

"I'm not saying there is zero risk associated with the coronavirus vaccines, just like any other vaccines or medications, but the benefits of vaccination outweigh the risks," he said.

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