Research notes

Research notes

96 I n f e c t i o u s Diseases N e w s l e t t e r cost $91~995/year. A program to immunize high-risk medical center personnel and to accomodate res...

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96 I n f e c t i o u s Diseases N e w s l e t t e r

cost $91~995/year. A program to immunize high-risk medical center personnel and to accomodate residual hepatitis B virus problems in nonimmunized individuals would cost $206,304 in the first year. Dr. Hamilton calculates that by seven years the cumulative costs of an immunization program would equal those without a program and at ten years would be cost saving. Given these assumptions, he believes that HBV is a cost beneficial alternative for a major employee health hazard. Detailed analyses are presented in his article. JAMA 250:2145, 1983 RESEARCH NOTES Meningococcus an~ Human Nasopharyngeal Mucosa: Stevens and colleagues investigated the mechanisms whereby Neisseria menin@iditis established a carrier state or invaded mucosal surfaces of a host. They developed an experimental model of human columnar nasopharyngeal tissue in organ culture and examined the interaction of encapsulated, piliated meningococci with this mucosal surface. Electron-microscopic studies showed that meningococci attach selectively to nonciliated columnar cells of the nasopharynx. Following attachment, the microvilliae of these nonciliated cells elongated and surrounded the organisms. Six to twelve hours after infection endocytic vacules containing meningococci were seen in some nonciliated columnar cells. Later, diploeocci were seen in the subepthelial tissues adjacent to lymphoid tissue. This observation suggested that meningococci had penetrated the epthelial layer. The interaction of meningococci with the nasopharyngeal epithelium may be an important means for meningococcus to establish a carrier state or invade the host. J Infect Dis 148:369, 1983 Reye's Syndrome: There were 97 cases of Reye's syndrome in southwestern Pennsylvania during ii years of surveillance. Ruben and colleagues investigated the epidemiologic features of these instances of Reye's syndrome. They note that the peak incidence was in February and March which corresponded to periods of influenza A and B activity in the community. Influenza was associated with 45% of patients, varicella with 19% and the remaining 36% of cases did not occur during periods of influenza activity. Reye's syndrome occurred significantly more frequently in suburban and rural areas than in the central cities, and more frequently among white persons than black, and more frequently in counties where the total population was young (under 17 years of age). The mean age of

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cases was 7.~ years with 57% female. Case fatality declined over the period of observation from 55% in 1970-75 to 16% in 1976-80. The authors' data suggest an apparant specificity of certain influenza A strains for Reye's syndrome. No case of Reye's syndrome occurred during a particularly large outbreak of A-England whereas cases did occur when A-Hong Kong, A-Port Chalmers, A-Victoria, and A-USSR were the only influenza s t r a i n s r e c o v ered. The study did not take into account the various factors that have been implicated in the causation of Reye's syndrome and although the authors conclude that the geographical distribution suggest environmental factors, they have no direct data to support this contention. Am J Publ Health 73:1063, 1983 Passive Trans-placental Immunization in New Zealand White Rabbits: Kleinman and colleagues immunized female rabbits with bovine serum albumin (BSA) and then tested litters which had never suckled from immunized and nonimmunized rabbits at 4 hours, 24 hours, and 48 hours after birth. After obtaining initial blood sample, all infant rabbits were gavaged with 100 mg bovine serum albumin plus tracer amounts of radioactive labeled BSA. Infant rabbits born to immunized mother had circulating antibody before feeding and pups from nonimmunized mothers had no detectable antibody to BSA. The fed animals were sacrificed at 3 to 4 hours after gavage. Serum obtained from cardiac and portal vein blood was examined for protein bound radioactivity and for the presence of immunoreactive BSA. All infant rabbits had radioactivity in their blood. Approximately 50% of the radioactivity in the serum of infant rabbits from nonimmunized does was protein bound and all of these animals had immunoreactive BSA in portal or cardiac serum samples. Of the 33 infant rabbits from immunized does, only 4 had protein bound radioactivity in their serum which seemed to be associated with circulating immune complexes. None of the 33 infant rabbits had immunoreacrive BSA detectable by electroimmunodiffusion. The authors suggest that one possibility for passive provision of systemic antibodies to the neonate is that IgG antibodies provide a back-up system for effectively removing enteric antigens that have avoided mucosal exclusion mechanisms. They suggest that this back-up mechanism might be especially useful during the neonatal period when intestinal secretions are deficient in antibodies that contribute to immune exclusion of food and other antigens. Pediatr Res 17:449), 1983

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