TOKYO, Oct. 16 (Xinhua) -- The number of cases of rubella infections in Japan this year has spiked to more than 1,100 cases, 12 times higher than the whole of the previous year, with more than 70 percent of the cases located in Tokyo and its surrounding prefectures, the National Institute of Infectious Diseases (NIID) said Tuesday.
According to the institute, the latest figure marks the first time that the number of patients with the infection has topped 1,000, with the epidemic here notably increasing since late July.
Across Japan, medical institutions have been reporting increasing numbers of new cases, with the first week of October seeing 135 new cases from the previous week and 1,103 cases for the year up until now.
According to the institute's latest report, by region, 45 new cases were reported in Tokyo, 20 new cases in neighboring Chiba Prefecture and 21 in nearby Kanagawa Prefecture.
Upwards of 70 percent of those with the disease are based in Tokyo and its peripheral prefectures, such as Ibaraki and Saitama prefectures.
"We need to keep monitoring the situation carefully to see if it will develop into a major epidemic," Japanese Health Minister Takumi Nemoto was quoted as telling a press briefing on the matter.
He added that the health ministry will encourage women planning to get pregnant to take a rubella antibody test.
There was a major outbreak of the virus in Japan with more than 16,000 people being infected in an epidemic between 2012-2013. Of the 45 babies which developed congenital rubella syndrome, 11 of them died.
In light of the latest outbreak, the institute has voiced its concerns that the viral infection, which can often be transmitted through coughing and sneezing and is also known as German measles, could affect the Tokyo Olympic and Paralympic Games in Tokyo in 2020.
The institute is urging people, particularly men in their 30s to 50s, to get vaccinated.
So far, the institute said, vaccinations of this demographic have been insufficient, most likely because these men did not have adequate vaccination shots when they were children, or were not vaccinated at all.
The cause of rubella is a highly contagious virus that can be passed from person to person when an infected person coughs or sneezes, or it can spread by direct contact with an infected person's respiratory secretions, such as mucus.
It can also be transmitted from pregnant women to their unborn children via the bloodstream.
There can be serious health implications if the disease is contracted by women in the early stages of pregnancy as it can cause serious birth defects such as heart disorders, hearing impairments, cataracts, growth retardation and intellectual disabilities in babies.
The highest risk to the fetus is during the first trimester, but exposure later in pregnancy is also dangerous, according to medical experts on the matter.
The institute says that women who are planning to become pregnant should receive a vaccination followed by a booster shot, with the vaccination alone likely being effective in preventing the disease.
Women who are already pregnant, however, cannot be vaccinated because the vaccine itself could harm the baby.
The institute is also calling on family members and others close to pregnant women to receive vaccinations if they have never had the disease or do not have records of having received the requisite vaccinations when they were children.
Local media reported Tuesday that a pro-vaccination nonprofit organization is calling on the government here to pay the costs of vaccinating at-risk middle-aged men and import more vaccines from overseas if supply in Japan to deal with the latest epidemic is insufficient.