TOKYO >> Japan’s first vaccinations against the coronavirus started Feb. 17, with health care workers at 100 medical institutions nationwide getting inoculated. Vaccinating this first-priority group will allow the government to verify the safety of the vaccines before the shots are made available to the public later this year.

Vaccines are expected to prove highly effective in containing the incidence and impact of the disease, but in Japan, vaccination rates can be low due to a culture of skepticism about vaccine safety and intense concern over side effects.

Much of the wariness has its roots in decades of mistrust after deaths in the 1970s following a diphtheria- whooping cough-tetanus vaccine, and in the early 1990s, cases of meningitis among children who received a measles-mumps-rubella vaccine. After related lawsuits, Japan has lagged in its vaccine program.

Given the country’s history, the government aims to secure the public’s confidence by being transparent about side effects.

“The most important thing is to properly convey information about the vaccine’s safety. We will swiftly report the information we obtain,” said Suminobu Ito, a member of a study team that will analyze data on side effects.

The team will begin with a detailed survey of 20,000 vaccinated health care workers. They will measure swelling in the injected area and keep records on whether workers experience headaches or fatigue, and how acute those conditions are over the first week after each vaccine dose.

The team will monitor participants over seven weeks to analyze such factors as the group’s infection rate with the coronavirus. Data will be compiled promptly, and findings will be made public weekly.

Only 160 people participated in a Japanese clinical trial of the Pfizer vaccine before its approval by the health ministry, not enough to get a thorough assessment of its side effects.

Said Ito: “The side effects of the vaccine may vary depending on country or region … We want to check the side effects based on data collected from a large number of Japanese people.”

Being proactive is important, the government says, because how information is conveyed will greatly impact the vaccine’s credibility with the public — and the number of people who get vaccinated. Focusing solely on side effects, for instance, could slow the pace of vaccinations and the time it takes to get infections under control.

International clinical trials have demonstrated the Pfizer vaccine’s high efficacy, reducing the incidence of COVID-19 by 95%. The vaccine, the first approved by the health ministry, sets off a strong immune response, and likewise strong side effects.

It has also shown a high incidence of pain at the injection site, fatigue and headache. Most of the symptoms subside within a few days. But some people have coronavirus symptoms, such as a 102-degree fever. Anaphylactic shock, an acute allergic reaction, has occurred in one out of every 100,000 to 300,000 people.

“Under the present conditions, the benefits (of the vaccine) are considered to be far greater than the risks,” said Junichiro Nishi, chairman of the vaccine committee of the Japanese Association for Infectious Diseases.

“It is important that the central and local governments distribute relevant information that is accurate and easy for people to understand, so that people can make their decision based on lots of facts.”