We had previously published several papers which revealed a diagnostic usefulness of indirect hemagglutination test of Shigella sonnei. Using this method, the present studies in the antibody response of patients with Shigella flexneri 2a dysentery were undertaken. This paper describes the results of serological investigation performed on 412 sera samples from 162cases who were treated at Osaka Municipal Momoyama Hospital during 1968-1969. The cases included 53 of Sh. flexneri 2a-positive, 18 of Sh. sonnei-positive, 5 of Sh. flexneri-positive (except F. 2a), 6 of Salmonella or entero-pathogenic E. coli positive and 81 of entero-pathogenic organisms negative patients and carriers. The indirect hemagglutination was modified somewhat from Young's method, and used for serological test. The summary is as follows: 1) In the case of Sh. flexneri 2a-positive patients: a) F.2a-HA antibody levels rose untill around 10th day of illness, and thereafter reached plateau or went down. b) The distribution of F.2a-HA antibody titers moved from low to higher levels of titer during 3 weeks of illness, and returned to the original levels at the 4th week. 2) In the case of Sh. flexneri 2a-carriers: a) The levels of F.2a-HA antibody were stable and had almost no characteristics. b) Antibody level distribution of F.2a-HA titers had two peaks at 1: 160 and 1: 5120. 3) In the case of healthy controls: The F.2a-HA antibody levels were less than 1: 640, and the titer at the peak in the antibody level distribution was 1: 160. 4) The critical titer in the F.2a-HA test with nonabsorbed sera was 1: 320, and this titer or over was determined as positive. 5) In the case of Shigella and any other entero-pathogenic organisms negative patients: Cases with positive F.2a-HA antibody were 37/75 (49.3%), and those with positive Sonne-HA antibody were 12/75 (10.7%). 6) Cases with F.2a-HA antibody 1: 640 or over (38/39) were observed to have titers of 1: 80 or over in bacterial-agglutination antibody against E. coli 0-13, showing the common antigenicity between E. coli 0-13 and Sh. flexneri 2a. 7) The effect of absorption with boiled bacilli of E. coli 0-13: a) Cases of Sh. sonnei-positive patients with titer of 1: 1280 or over in both F.2a-HA and Sonne-HA antibody, were shown to have no F.2a-HA agglutinin and to nave at least 1: 160 titer in Sonne-HA antibody. b) Cases of Sh. flexneri 2a-positive patients and carriers with titer of 1: 1280 or over in F.2a-HA antibody, were shown to have no Sonne-HA agglutinin and to have at least 1: 160 titer in F.2a-HA antibody. c) In the cases of healthy control sera, both Sonne-HA antibody and F.2a-HA antibody were lost completely. Above results a), b), c) lead to the conclusion that absorption procedure with E. coli 0-13 was necessary for the serological diagnosis of Shigella flexneri 2a dysentery in F.2a-HA test.
In 1966 a rubella epidemic occurred among school children in Fukuoka city, however, few cases with congenital rubella were born there. Under these circumstances we examined the frequency of rubella hemagglutination inhibition (HI) antibody among pregnant women in this district before and after the rubella epidemic. Our previous study indicated that the frequency of rubella neutralizing antibody among 200 pregnant women in 1965 in this district was 65%, however, by utilizing the newer, simpler and more accurate HI test, rubella HI antibody was detected in 85% of the same specimens. As the post-epidemic study, serum specimens were obtained from 225 pregnant women in Fukuoka city September through December in 1969. Rubella HI antibody was detected in 88% of the specimens tested. The fact indicated that this 88% of the population tested had experienced rubella at some time in their lives and also indicated that 12% of this population did not have antibody and were susceptible to rubella. The frequency of rubella HI antibody was 15%, 13% and 5% in the age groups 21-25 years, 26 30 years and 31-35 years, respectively, and the difference was not significant. There was no significant difference in the frequency of pregnant women susceptible to rubella before and after the epidemic. The 1966 rubella epidemic in Fukuoka city was not extensive as usual and 12% of the pregnant women were still at risk in the rubella infection, and that is the reason why rubella vaccine is needed there. We should examine the frequency of rubella antibody among children and then discuss the rubella vactination program in this district.