الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Meningococcal meningitis is a major public health problem in many parts of the world particularly following prevalence of sulfonamide resistant strains, as well as evidence of beginning resistance to some antibiotics. Acti ve immunization has been suggested as an alternative control measure. Over the last few years, clinical trials undertaken in many parts of the world have shown clearly that meningococcal polysaccharide vaccines prevent meningococcal diseases, whether meningococcal vaccination prevents transmission of meningoccoci is less certain. It was pointed out that the ideal vaccine should not only protect the immunized host against clinical disease but also interrupt the chain of transmission of pathogenic organism, thus, interfering with the carrier state and diminishing the spread of the disease. Therefore, it was considered worthwhile to immunize the central security forces - a group at maximum risk -with the meningococcal polysaccharide vaccine to test its effectiveness against meningococcal carriage. This study was carried out on 400 individuals - who had not been previously vaccinated selected from Elamria training security forces centre in Alexandria. All relevant information were collected from every individual including the age, level of education, residence, previous history of meningitis, and number of members in each barracks. Four throat culture surveys were performed on all the members of the sample with an intervals of 1-2 weeks between each (WO consecutive surveys with the aim of determining the carrier state. Out of 400 individuals 173 were vaccinated with the serogroup A and C meningococcal polysaccharide vaccine. Another four throat culture surveys were carried out on all the members of the sample 2 weeks after vaccination as mentioned before with the aim of studying the efficacy of the meningococcal vaccine against meningococcal carriage. Throat swabs were taken with sterile polyester fiber tipped applicators inoculated immediately on Thayer Martin plates and incubated at 37°C in 5-10 CO2 by candle jar for 24-48 hours. The isolated colonies were subjected to Gram .” stain, oxidase test, sugar fermentation, sero-agglutination and antibiotic sensi tivi ty. The main results of the study were as follows: 1 - The carrier rate increased gradually during the period of study from 33.25 in the first survey to 39.26 in the last survey. This can gradual be attributed to Increase overcrowding as recruits live together in close contact in barracks (About 200 each). 2 - The most frequent meningococci isolated were serogroup B, followcd i.n frequency by serogroup Z, non typable, A and serogroup X. Serogroups Y, C and D remained clearly at lower level. This suggests that serogroups Band Z become an important meningococcal agents in Egypt. 3 - Serogroup replacement was observed during the follow up study which would suggest that some strains are able to live together in the host (as evidenced by the occasional detection of carriers of more than one serogroup) and one of them may predominate ’. Serogroup B was the most frequent one (15.4). 4 - A considerable proportion (15.3 ) of the meningococcal strains diagnosed sero non-typable the first as In agglutination after subculture became typable. This means that subculture is indispensable to find the true relative distribution of the serogroups.