Fourteen cases of meningococcal infection showing meningitis, sepsis or other clinical symptoms, April 1998- October 1999 - Tokyo, Japan
(IASR 2000; 21: 54-54)

During April 1998 to October 1999, 14 cases due to Neisseria meningitidis infection are reported in Tokyo. Of these, 9 cases developed meningitis, followed by 2 septicemia, one pneumonia, one upper respiratory tract infection, and one urethritis case. Non-meningitis cases are supposed to have Neisseria meningitidis infection only. Isolated strains are forwarded to the Tokyo Metropolitan Research Laboratory of Public Health for serotyping.

Age distribution of the cases is shown in Table 1. One case was under one year old, followed by 2 in 10-19 years old, 2 in 20-29 years old, and 4 at or greater than 40 years. Meningococcal meningitis is generally seen those under 15 years old, especially infant. However, reported cases included not only young children and young adults, but also those in 50-60 years old. Reported cases were divided into 5 males and 4 females, so that there was no difference in sex. Of 5 cases in which developed septicemia, 2 cases with septicemia only were in 20's and 30's, followed by one case with pneumonia in 30's, one case with upper respiratory tract infection in 40's, and one case with urethritis in 20's.

Neisseria meningitidis was classified in 13 serogroups (A, B, C, D, H, I, K, L, X, Y, Z, W-135, 29E) by antigenicity of its capsule. Of 9 cases in which developed meningitis, 8 cases were in serogroup B, and one remained untypable (UT). Two septicemia cases were in serogroup C and W-135, the pneumonia case in serogroup W-135, the upper respiratory tract case in serogroup B, and the urethritis case remained UT.

Further investigation was carried out toward case families. The father of the infant case with meningitis yielded the same serogroup B strain. A child of a 30's case with pneumonia was infected with serogroup W-135. Gargling fluid from 71 close contacts with 5 cases with meningitis or septicemia were collected for bacterial isolation, however results were all negative.

Although majority of meningitis are aseptic in Japan, not a few meningococcal meningitis are reported in Africa and other regions of the world. Serogroup A strains are epidemic in Africa and some parts of Asia, such as Vietnam, Nepal, and Mongolia. Serogroup B strains are isolated in an outbreak in the United States (July-August, 1995, 480 cases), an outbreak in a care facility in Florida (1997), and an epidemic in New Zealand (1996-98, approximately 1,300 cases). Serogroup B and C are causative strains to an epidemic in United Kingdom (1997-98, approximately 600 cases). During December 1999 to January 2000, some 30 cases are reported from Hungary. These Tokyo cases are all sporadic, and although 2 carriers are found, the cases' families are asymptomatic. In Tokyo 1-2 meningococcal infections are reported annually these few years, but the case accumulated to 14 during 1998 and the first half of 1999. The meningococcal infections should be carefully observed.

Reported by Miyoko Endoh, Rumi Okuno, Yukako Shimojima, Iwao Murata, Hiromasa Sekine, and Yataro Kokubo, Tokyo Metropolitan Research Laboratory of Public Health.

Correspondence:Fax: +81-3-3368-4060

Return to the TopPage

Back to Home