TOKYO, May 18 (Xinhua) -- The total number of cases of A/H1N1 flu infections, both domestic and those contracted abroad, topped 130 in Japan Monday, according to Kyodo News calculations.

People wear face masks at a shopping street in Kobe, western Japan, May 17, 2009.   (Xinhua/Reuters Photo) Photo Gallery>>>

    The surging number made Japan the country with the fourth largest number of infection and put it on high alert, though by far the patients are mostly confined to the Kansai region, in particular, Osaka and Hyogo Prefectures.

    Japanese government on Monday convened an emergency task force meeting to discuss countermeasures on the spread of the epidemic.

    At the meeting, Prime Minister Taro Aso called the public to remain calm, saying the Japanese government has no plans to ask citizens to refrain from holding meetings or scale down corporate activity.

    The government task force decided not to upgrade its measures aimed at coping with the spread of the new flu from the current phase 2, which refers to an early stage of domestic outbreak, according to Kyodo News.

A railway conductor and a passenger wear facemasks at a station in Kobe, Hyogo prefecture, in western Japan, May 17, 2009.  (Xinhua/AFP Photo) Photo Gallery>>>

    But the country is facing the risk of large-scale outbreak in its populous cities which could lead the WHO to raise its new flu pandemic alert from the current 5 to the highest level of 6, which means community-level outbreaks in two different WHO regions, experts has warned.

    The WHO is launching investigation on the situation in Japan.

    The newly confirmed domestic cases included high school students, college students, their family members and teachers, as well as bank clerk and people working at a local railway ticketing office.

    Nearly all the schools in the two prefectures are closed, as many of the infected are students.

    The symptoms among Japanese patients are relatively light compared with those in North America, and none of the 130 people are in critical condition.

Train station staff in Kobe in western Japan on May 17, 2009.   (Xinhua/AFP Photo) Photo Gallery>>>

    Japan on Saturday confirmed the first eight cases of domestic infection on students of a Kobe high school. The later confirmed cases in Osaka are said to have contact with the Kobe students through a volleyball match. Osaka and Hyogo are adjacent in the Kansai region.

    In Osaka, Japan's second largest metropolis, many of the infected are students at the Kansai Okura Senior High School. A total of 143 students at the school have shown symptoms of influenza since around last Monday, according to local media reports.

    Osaka Governor Toru Hashimoto convened a meeting of a new flu task force on Sunday and decided to ask facilities such as movie theaters to suspend operations to prevent the spread of the flu.

    TV clips showed people in Kansai region started to wear masks in public spaces and rushed to drug stores for buying flu medicines and masks.

    On the Tokyo Stock Exchange, mask fiber makers are the most remarkable gainers Monday, bucking the trend of across-the-board decline. Toabo surged almost 44 percent and Shikibo gained 50 yen, or about 37 percent.

People wearing protective masks walk on a street in Kobe in western Japan on May 16, 2009.  (Xinhua/AFP Photo) Photo Gallery>>>

    The Japanese government on Saturday shifted the stage of its new-flu action program from "a period of overseas outbreak" to "an early period of domestic outbreak" and called for companies and schools in the areas concerned to allow individuals to avoid commuting during rush hours.

    The Kyodo News quoted Masato Tashiro, a member of the World Health Organization's emergency committee, as saying that several hundred people in Japan already may have been infected with the new flu.

    Japan's first four cases of infection were confirmed on people who returned from North America.

A parent and child undergo a check-up at a tent for fever outpatients in front of a hospital where high school students infected with new H1N1 influenza are hospitalized, in Kobe, western Japan, May 16, 2009.   (Xinhua/Reuters Photo) Photo Gallery>>>

Special Report:  World Tackles A/H1N1 Flu