The recent discovery of psittacosis in avian species and human beings in this country emphasized the disirability of a more extensive survey of this disease. In diagnosis of the disease the complement fixation test has been extensively used. The hemagglutination inhibition test of psittacosis developed by Hilleman et al. is also available for this purpose, although it is not extensively utilized at the present. For 2 years and 3 months from October, 1956 to December, 1958, 125 cases of primary atypical pneumonia, 78 cases of acute bronchitis, 3 cases of middle lobe syndrome and 137 cases of other miscellaneous diseases were tested by the hemagglutination inhibition test. 1. Titers of 1:20 or higher were found in 23.4 and 21.7 per cent of patients with primary atypical pneumonia and with acute bronchitis, respectively, while the incidence in the control group of patients was only 6.7 per cent. This finding suggests that in the groups of patients with those respiratory diseases psittacosis patients were present. No significant trend in the antibody distribution by age was demonstrated in any of the groups of patients. No change in incidence of antibodies according to weeks after onset of disease was observed. 2. No difference in incidence of antibodies was found between male and female. 3. In the group of patients with miscellaneous diseases other than acute respiratory infections the antibody titer was generally low. None of the patients showed titers of 1:80 or higher. In the groups of patients with primary atypical pneumonia and acute bronchitis patients with high titers were frequently found. This also suggests that there are psittacosis patients in those groups. 4. Patients with four-fold increase or decrease in titer or unusually high titers (1:80 or higher) were found in 13.6 (17 cases) and 6.6 (5 cases) per cent in the groups of patients with primary atypical pneumonia and acute bronchitis, respectively. Those patients showed the same clinical symptoms as described for psittacosis. Of 3 cases with middle lobe syndrome 2 were serologically diagnosed to have recent infection with psittacosis virus. The syndrome of those cases was probably caused by psittacosis infection. The appearance and persistence of the antibody in those serologically diagnosed cases were analized. 5. Parakeets, pigeons, bengalees, Java Sparrows and canaries were suggested to be of primary importance as the source of psittacosis infection by statistical analysis of the correlation between the presence of the antibody in the patient and pet birds in his household. A similar analysis concerning domestic animals such as cattle, sheep, goats and cats revealed no correlation between the antibody of the patient and the domestic animals in the household.
A supernatant of bouillon cultures of S. miami contains a kind of phage. This is the phage which S. miami liberates and it is temporarily called λ phage. This phage is weak and is mostly inactivated by heating of 60°C for 30 minutes. This has closely serological relation with palos phage (this is the phage which S. paratyphi A komatsubara liberates) among the phages which we have studied in our laboratory. Futhermore, in the other characteristics its morphology of plaque and host-range are the same with the palos phage and only one step growth curve is different from the palos phage, and therefore we cannot say the two to be equal. On the other hand S. miami retains O [I] antigen. However, λ phage which is liberated from S. miami in the above mentioned method, is consequently of no use to convert O [I] antigen. Then, what controls O [I] antigen of S. miami? In case of superinfection of S. miami with s2 phage which S. typhimurium 4066 liberates by the same method as was followed on S. sendai at our laboratory, although it is a very small amount, the rate of 50 phages can be expelled from bacteria of 3×108/ml. This expelled phage was quite the same with that of p3 phage which is liberated from S. pullorum. Thus, as can be seen from this study, in respect of the phage, S. miami is the double lysogenic strain. Namely, it might be considered that λ phage existed as prophage in it and p3 phage attached to the bacterial chromosome of S. miami at the shape of “defective prophage”, and it proves that this p3 defective prophage controls O [I] antigen of S. miami. In this case also we did not use the word “defective lysogeny” but used the word “abnormal lysogeny” as in the case of S. sendai.
The status of outbreaks of poliomyelitis patients from 1956 to 1958 and neutralizing antibodies against the 3types of poliomyelitis virus in the normal population in 1957 and 1958 of Gifu Prefecture were investigated. 1) Although 117 cases were recognized in infants under 15 years old, attack rate was 88% under 5 years old and 60.7% in the 7/12 to 2 year group. 2) The majolity of patients broke out in summertime and seasonal index was 2.1 in 1956, 2.7 in 1957, and 5 in 1958, respectively. 3) Age distribution of neutralizing antibodies indicated that level of antibody was lowest in infants aged 7/12 to 2 years (no antibody except 16.6% for Type I), after which it jumped to 30-50% in the 3 to 5 years and the level of positives increase to 92.7% for Type I, 85.7% for Type II, and 75% for Type III over 16 years old. 4) The highest incidence and the lowest level of antibodies were both in the 7/12 to 2 year age group. It was recognized that decrease of incidence and increase in antibodies were nearly pararell with age, and some relation between attack rate and distribution of antibodies was exist.
An active turnover of RNA-phosphorus assimilated after phage infection has been revealed. It was also found that chloramphenicol, when added 10 minutes after T2 infection, blocked the breakdown of RNA formed after infection, but not the synthesis of new RNA, indicating a correlation between RNA breakdown and protein synthesis. From these results it is concluded that the RNA, which is formed after infection, is distinct from the RNA of the host cell in metabolic activity.
In order to investigate the inapparent infection of poliovirus, isolation of the virus from feces and neutralization tests (NT) were carried out on fifty healthy infants and children who were randomly selected from general population in Arakawa and Shinagawa area, Tokyo, and forty one healthy infants and children of two nurseries in Tokyo from May to Oct. of 1957. The feces for the virus isolation were collected from those infants and children once a month during that period. The NT antibodies was examined on two serum samples taken in May and October, during which poliovirus infection might be prevalent. The results were as follows: 1) Poliovirus and the other enteroviruses were isolated from 12% of 183 fecal specimens collected in Arakawa and Shinagawa areas, and 38% of them were poliovirus and 8.1% the enteroviruses. 5.9%, of 17 sera collected from the children in Arakawa area and 33.3%, of 9 sera collected from the children in Shinagawa area showed positive conversion of the NT antibody against poliovirus between May and October. 2) These investigations indicatedd that 21.1%, of 38 infants and children from general population of Tokyo who were successivelly observed during six months, suffering from the inapparent infection with poliovirus, namely, the inapparent infection rate of poliovirus was 21.1% of healthy infants and children under 2 years of age in Arakawa and Shinagawa areas during 6 months of the summer of 1957. Since the population under 2 years of age in Arakawa and Shinagawa areas was 27, 128, and four had developed paralytic poliomyelitis during the same period, it was calculated that a patient with paralysis was probably surrounded by 1431 individuals of the inapparent infection. 3) The age distributions of the inapparent infection rate were 21.4% from 6m to 11m old, 25% from 1y to 2y old, but that of children elder them 2 years old was not clear. 4) In K and H nurseries the inapparent infections were found in 93.3 and 100 percent of 15 and 17 infants respectively. It reveales quite high infection, rate of poliovirus in such groups as nursery or household, if the virus is once introduced. 5) The high incidence of infection with ECHO type 6 and ECHO type 7 were observed in K and H nursery respectively about the same time to the poliovirus episode. The age distribution of NT antibodies against ECHO type 7 virus isolated from H nursery were tested in 71 sera collected in Tokyo; the results indicated that the rate of antibody positives was lower than that of polio NT antibodies even in higher age groups.