1. Occurrance of patients during recent endemic of Shichito fever was only 12 cases. Only one isolation of R. tsutsugamushi (Rt) (Karp type Miyake strain) from field rodents and chiggers was successful from an antibody negative Rattus norvegicus in nude mice. This might be due to few virulent Rt harboring field rodents and chiggers in nature. Miyake strain could grow only in nude mice and not pathogenic for conventional hairy mice. These results were quite different from previous one and recent endemic might be caused by the avirulent strain of Rt. 2. Karp type Rt was isolated in BALB/c (+/+) mice from a patient in Niijima Island who showed typical clinical signs. 3. Chiggers: L. scutellare, L. pallidum. L. fuji, L. kitasati and G. sadasky were collected through 4 field surveys and most of them were former 2 species. The dominant species was L. scutellare during the occurrence of patients.
Karp type R. tsutsugamushi (Rt), Miyake strain, was isolated in BALB/c nu/nu mice (A nude mice) from an antibody negative Rattus norvegicus captured in November 30, 1977 at Miyake Island. Its characters are follows: 1. Miyake strain could grow only in nude mice and would'nt grow in conventional mice. For the maintenance of this strain, nude mice passages were necessary. 2. MID50 and MLD50 of Miyake strain titrated in A nude mice were 10-5.2. Mean survival day of infected A nude mice was 12.6 days when challenged intraperitoneally with the dose of 1, 000 MLD50. It was grown only in peritoneal cavity. These findings were proportional to the amount of infected Rt. When infected subcutaneously, average survival day of nude mice was 17-18 days and it was grown poorly in mesothelial cells in peritoneum. Splenomegaly and lymphnode swellings were prominent and it was well grown in these organs. Anti-Rt antibody was not detected in these mice. 3. MID50 and MLD50 in another homozygous nude mice (B nude mice) were 10-4.8 and they were not so different from the values in A nude mice. When infected intraperitoneally (1, 000 MLD50) in nude mice, mean survival day was elongated up to 17.0 days. Slight splenomegaly was noted, however there was no viscous exudate in peritoneal cavity. Transdate in a pleural and peritoneal cavity and adhesion of intestine were observed. Proliferation of Rt in mesothelial cells was milder than that in A nude mice. These finds were correlated well with infected dose. No antibody was detected in B nude mice. 4. Miyake strain was not grown in DDD mouse. Antibody produced in this mouse was proportional to the infected dose. 5. Proliferation of Miyake strain in nude mice could not be prevented by passive transfer of homologous antibody.
According to the statistics of protozoal and metazoal infected patients admitted to our hospital during 1965-1979, malaria was the most frequently encounted infection (104 cases) and filariasis (43), taeniasis saginata (29), diphillobothriasis latum (15), and giardiasis (8) followed in that order. Number of eosinophils were as follows. (Mean±S.D./mm3) malaria: 69±79, toxoplasmosis: 195±167, giardiasis: 1237±2387, clonorchiasis: 341±279, paragomiasis: 6165±3786, diphillobothriasis latum: 210±89, taeniasis saginata: 507±423, and filariasis: 252±260. As for malaria, eosinophils were decreased in number, especially in Plasmodium falciparum infected patients, 33.939.3/mm3. In two out of eight patients of giardiasis, eosinophilia was revealed, but these two patients have another parasites. So it is not clear whether the eosinophilia was caused by giardiasis or not. In four out of eight patients, serum alkaline-phosphatase was found to be increased. In patients with paragoniasis, eosinophilia was most marked. In taeniasis saginata, eosinophilia was observed, but in diphillobothriasis latum, it was not. Eosinophilia was not always reavealed in these diseases. It may be depend on the nature and stage of diseases.
A field experiment was carried out with influenza vaccines prepared from various strains. Its purposes were to examine each vaccine for effect on the living body to increase in titer of hemagglutination-inhibiting (HI) antibody and neuraminidase-inhibiting antibody and for effect of inoculation. 1. Inoculation was done with three vaccines, vaccine prepared from the A/Kumamoto/22/76 (H3N2) strain and A 1 (OH) 2-added adjuvant vaccines from the A/Kumamoto/22/76 (H3N2) strain (800 and 400 CCA/ml, respectively). Neuraminidase-inhibiting antibody in the serum was estimated before and one month after inoculation. No rise in antibody titer was seen in those inoculated with the first vaccine. A two-to fivefold increase in antibody titer was noticed in three of nine persons inoculated with the adjuvant vaccine (800 CCA/ml) one month after inoculation. An increase 40-70 times on the average was observed in those inoculated with the adjuvant vaccine (400 CCA/ml) one month after inoculation. Some persons were selected from among those inoculated with these vaccines, except the adjuvant vaccine (400 CCA/ml). In each of them the effect of vaccination was compared between HI and neuraminidase-inhibiting antibodies. The same degree of increase in titer was not always seen in both antibodies. 2. Ability to produce antibody was compared between vaccine prepared from highly multiplicableinfluenza virus [A/Kumamoto/22/76-A/PR/8/34 (H3N2) strain] and vaccine from the A/Kumamoto/22/76 (H3N2) strain. When the vaccine strain was used as antigen, a more than fourfold increase in HI antibody titer was found in 60% of those inoculated with the latter vaccine one month after inoculation. It was found in 73% of the same inoculated persons at the same time when the former strain was used as antigen. When the vaccine strain was used as antigen, a more than fourfold increase in HI antibody titer was noticed in 76% of those inoculated with the former vaccine one month after inoculation. It was noticed in 64% of the same inoculated persons at the same time when the A/Kumamoto/22/76 strain was used as antigen. There was no large difference in ability to produce antibody in human beings between vaccine prepared from the original strain and recombinant virus vaccine.
TC resistant Shigella strain was obtained by selecting on TC containing agar media after mixed culturing of antibiotic resistant E. coli and sensitive prototrophic Sh. flexneri 3a.Comparison of biochemical and serological characters between the TC resistant Shigella strain and the Cd, Zn resistant one, which was reported in the previous paper, was carried out. The reduced type of sulfur compound was strictly required for the growth of the Cd, Zn resistant strain, but not for the TC resistant one. The Cd, Zn resistant factor was more stable than the TC resistant factor against the treatment with acriflavine as well as with ethidium bromide. So the Cd, Zn resistant strain might be adopable as one of useful markers on the experimental study of Shigella infection. Cd uptake of the Cd, Zn resistant strain was decreased, while Mg uptake was increased as compared with those of the original strain and the TC resistant strain. There was no difference on Zn or Mn uptake among these three strains. These strains gave identical results concerning biochemical and serological characters, and it was found that an acquisition of Cd, Zn or TC resistance had nothing to do with the toxicity of these organisms.
This is a case report of a 37-year-old housewife who died on the 2nd day of admission. She had continuous fever at over 38°C for 3 months prior to admission and did not receive any antibiotics. Shehad an acute onset of severe pain in the left upper quadrant of abdomen on the day before admissionand was admitted on May 22, 1979. She had a history of cardiomegaly and heart murmur since the age of 20. On admission, physical examination revealed heart murmur and friction rub in splenic area. Three separate blood cultures showed all grew alpha-hemolytic streptococcus. She was diagnosed subacute bacterial endocarditis and treated with a large doses of Penicillin G, but developed shock and died on the 2nd day of admission. Autopsy revealed a ruptured mycotic aneurysm of 2 cm in diameter of the superior mesenteric artery. There was massive hemorrhage into intraabdominal cavity. There were also splenic infarction and large vegetations on the aortic valve. It may be considered that this is the first case of subacute bacterial endocarditis associated with mycotic aneurysm of the superior mesenteric artery in Japan.