The increase in the number of rubella patients continues unabated since it spiked in late July mainly in the Tokyo metropolitan area. According to the National Institute of Infectious Diseases, the cumulative number of patients this year reached 1,692 at the end of last month — 18 times more than the figure of the whole year of 2017 and the largest since the last major outbreak in the 2012-13 period, when the nation had roughly 16,700 patients in two years. Rubella cases have been reported throughout the country.
The latest outbreak of rubella, if protracted, could threaten the government’s target of eliminating the disease in Japan by fiscal 2020, and also raise concern about the possibility of an outbreak occurring just as the nation hosts the 2020 Tokyo Olympic and Paralympic Games. Concerned parties need to take prompt action to contain the infection, in particular by ensuring that men in their 30s to 50s who, compared with other generations, are believed not to have been sufficiently vaccinated against the highly contagious disease, take the necessary measures to avoid infection. If carriers of the virus pass it on to pregnant women, there is a high risk that it could cause a range of serious fetal defects, including heart disorders, hearing impairment, eye problems, brain damage and even death.
The rubella virus is often transmitted through coughing and sneezing, and is more contagious than influenza. Although symptoms in children who contracted the disease tend to be minor such as rash and fever, the risk of causing congenital rubella syndrome (CRS) in the developing fetus is high if women who don’t have sufficient immunity against the virus get infected by around the 20th week of their pregnancy. Although no cases of CRS have so far been reported in the latest outbreak, at least 45 babies were born with the syndrome during the 2012-13 outbreak, of whom 11 died.
Last month, the U.S. Centers for Disease Control and Prevention issued a warning that pregnant women in the United States should not travel to Japan due to the ongoing outbreak unless they are protected against the disease by vaccination or previous infection. The Washington-based institute raised its alert level for the outbreak in Japan to “Level 2,” or the second-highest of 3 levels. The current situation could be potentially damaging for the growing inbound tourism to Japan.
The government’s vaccination policy against rubella should be promptly revamped. A large portion of the people who contracted the disease since the number of patients began to sharply increase in July are men in their 30 to 50s. Many of the men of this generation were reportedly not vaccinated in their childhood due to the changes in the nation’s vaccination policy — and are not sufficiently immunized against rubella compared with those in other age groups.
Since women who are already pregnant cannot get vaccinated against rubella because the vaccine itself can have an impact on the fetus, the key to containing the outbreak is getting men in their 30s to 50s vaccinated as quickly as possible. However, the steps taken in this regard do not appear sufficient.
The national and local governments are calling on women who expect to have children at some point and people who are living with pregnant women to take an antibody test to determine if they have been immunized against rubella, and will subsidize the cost. The Health, Labor and Welfare Ministry plans to expand the subsidies in fiscal 2019 to men in their 30s to 50s. The purpose of the test is identify who needs and doesn’t need the vaccination to ensure there will be no shortage of supply of the vaccine, which will also be needed for children.
That’s a rational policy. But doubts exist as to whether men in that age group will go through the trouble of first taking the antibody test and then getting vaccinated if necessary since for many that would mean taking time off from work on each occasion. The fact that adult men face little chance of developing severe symptoms if they get infected with rubella may also reduce incentive. They should, however, be reminded of the potential impact that their infection could have on others, including their family members and colleagues at work.
Experts say that no medical problems will result if people get vaccinated without first taking the antibody tests, and therefore people who live or work around pregnant women should get vaccinated without the antibody tests if they are known to be insufficiently immunized. Earlier this month, a group of medical organizations, including the Japan Pediatric Society and the Japan Society of Obstetrics and Gynecology, requested to the health ministry that the government work with employers to perform the antibody tests on men in their 30s to 50s at their workplaces, and called on manufacturers of the vaccine to increase production. The bottom line should be to make it easier for them to take the necessary measures to ensure they don’t get infected with rubella.