Investigations of Meningococcal Infection. I. Bacteriological Aspects 1

Investigations of Meningococcal Infection. Ii. Immunological Aspects 1

“…On the other hand, if a strain was generally resistant in fresh normal serum, it was also resistant when antiserum and normal serum were combined, but was destroyed when defibrinated blood was used as complement. Except for those differences in susceptibility, the strains were indistinguishable in their general characteristics, including morphology, agglutinability, quellung, and virulence for mice (17).…”

“…The results of this investigation have been reported in detail elsewhere (17,23), but the observations which are pertinent to the present study may be summarized as follows: (1) It was found that Group I meningococci could be divided roughly into two classes-those which were susceptible and those which were resistant to the bactericidal action of fresh normal human serum, as indicated by their failure or ability to survive (17). Some variation was al5o encountered in the bactericidal property of sera from different normal individuals; for example, occasional sera were found in which the usually susceptible strains were able to survive.…”

“…In the preceding paper (17), it was shown that the Group I carrier strains were of the same order of virulence for mice as the Group I strains from the cerebrospinal fluid of cases. In the present study, 4 Group I carriers were found to possess antibody levels which were as high as or higher than those in convalescent patients.…”

“…amounts, 30 minutes before the injection of organisms. The preparation of mucin suspensions was made in the same manner as that described for the virulence titrations in the preceding paper (17). White Swiss mice from a single breed, each weighing between 14 and 16 grams, were employed in all of the tests.…”

Serological Relationships Among Meningococci

“…With the advent of World War II, the usual increase in meningococcus infection again appeared, the highest incidence occurring during 1942 and 1943. Reports from France (54, 68), from Great Britain (24), and from Chile (53), as well as from the United States (36,66), indicated that Group I was again overwhelmingly predominant. According to Phair and Schoenbach (51) 91.6% of the cases of meningococcus infection in the U. S. Army during this time were due to Group I.…”