Decline of serum antibody in splenectomized children after vaccination with pneumococcal capsular polysaccharides.

Asplenic persons are at increased risk of overwhelming sepsis caused by Streptococcus pneumoniae. Vaccination with polyvalent pneumococcal polysaccharide has been shown to stimulate a nearly normal antibody response in these individuals, indicating that active vaccination might prevent pneumococcal disease in this population. To obtain information on the duration of protective levels of pneumococcal antibody, 33 asplenic children were vaccinated and antibody levels were measured at intervals for up to 4 1/2 years after vaccination. Significant antibody decline was observed in children who had undergone splenectomy because of trauma, but antibody decline was not observed in children whose spleens had been removed because of hereditary spherocytosis. There was a highly significant difference in rates of antibody decline among the 12 antibody serotypes measured: types 1, 4, 6A, 7F, 8, 19F, and 23F showed the greatest decline. Based on measured rates of antibody decline, subprotective antibody levels (antibody nitrogen less than 300 ng/ml) for types 7F, 8, and 19F would be reached 1 to 2 years after vaccination; type 6A never reached the protective level; and antibodies against the remaining eight types either were within the protective range initially or did not show significant decline. Asplenic children may benefit from revaccination with certain antigen types (7F, 8, and 19F) 1 to 2 years after initial vaccination.

Teichoic acid serology in staphylococcal infections of infants and children.

Counterimmunoelectrophoresis and gel diffusion were utilized for the detection and titration of antibodies to staphylococcal teichoic acids in various disease states caused by coagulase-positive staphylococcus in infants and children. Serum samples were obtained on admission and serially for 2 to 12 weeks during illness. Teichoic acid antibodies were found by CIE in 12 of 21 patients (57%) with invasive CPS disease with bacteremia (Group A), in two of 17 patients (12%) with CPS infection without bacteremia (Group B), in none of 27 patients with bacteremia and/or invasive infections caused by organisms other than CPS (Group C), and in none of 24 noninfected, hospitalized patients or healthy children (Group D). Gel diffusion was useful for titrating antibodies in seropositive sera. Teichoic acid serology is a useful adjunct in the diagnosis of invasive CPS infections. The presence of these antibodies by CIE and gel diffusion may help to identify patients with endothelial or metastatic infections associated with staphylococcal bacteremia.

The lack of nurse-infant transmission of type B hepatitis in a special care nursery.

Twenty-four infants cared for by a nurse who developed acute B hepatitis with HBsAg present in her serum and saliva were examined for serologic evidence of hepatitis B virus transmission. None of the infants had HBsAg by radioimmunoassay or anti-HBc by complement fixation. One infant had anti-HBs whose transient presence was consistent with passive acquisition. Using sensitive serologic tests, no identifiable risk to newborn infants in a special care nursery could be documented as a result of exposure to a nurse who developed acute type B hepatitis during their period of care.