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.     

Viremia in hospitalized children with enterovirus infections

In a prospective study during the summer and fall of 1982, enterovirus was isolated from 48 hospitalized children; in 29 (60%) enterovirus was isolated from CSF or blood, and in 19 (40%) only a presumptive diagnosis was established. Blood was positive in 21 (44%) and was the only positive specimen in two children. A presumptive diagnosis was provided within 4 days of admission in 38 (80%) and within 48 hours in 19 (40%) of the children from whom enterovirus was isolated. Viremia was most often detected in febrile infants younger than 3 months of age with a clinical picture simulating bacterial sepsis. The presence of viremia was inversely related to the presence of CSF pleocytosis and to virus isolation from CSF. The diagnosis of diseases caused by enterovirus is more accurate when blood culture is added to CSF stool and throat cultures.     

Immunization of 2-month-old infants with protein-coupled oligosaccharides derived from the capsule of Haemophilus influenzae type b

We studied an immunogen consisting of oligosaccharides derived from Haemophilus influenzae type b capsular polysaccharide (PRP) coupled to CRM197, a nontoxic relative of diphtheria toxin. Subcutaneous injections were given to eight subjects at ages 2, 4, and 6 months, simultaneously with conventional diphtheria-tetanus-pertussis (DTP) vaccine. After the first immunization, total serum anti-PRP antibodies declined in all subjects, but increased in most after the second immunization and after the third in seven of seven subjects analyzed. In these seven infants, the geometric mean level at age 9 months (0.73 micrograms/ml) exceeded by at least 40 times the means of historical control groups given DTP only or DTP plus (uncoupled) PRP vaccine. An isotype-specific assay showed that IgM antibodies increased after the first immunization with the coupled vaccine in all eight infants. Against the background of declining maternal IgG antibody, elevations in IgG antibody were detected after the second or third immunization in six of the eight. These six at age 9 to 11 months were immunized with (uncoupled) PRP vaccine, and a "boost" in anti-PRP antibody, including an IgG component, was found.     

Interferon production in children with respiratory syncytial, influenza, and parainfluenza virus infections.

To better understand the recovery process of infants with lower respiratory tract disease due to respiratory syncytial virus, the production of interferon by 129 children (ages 10 days to 24 months) with RSV infection was compared to that of 20 children with influenza (ages 1 to 36 months), and 37 children with parainfluenza virus infection (ages 4 to 66 months). Interferon assays of 285 nasal washes from children with RSV revealed that interferon production occurred in only 5 (4%) of the children. Significantly more children infected with infleunza virus, 55% (P less than 0.001), and parainfluenza virus, 30% (P less than 0.001), produced interferon. In addition, the quantity of interferon produced by children with RSV (geometric mean titer = 2) was significantly less than that of children with influenza (GMT = 26.8, P less than 0.001) and parainfluenza virus (GMT = 23.5, P less than 0.001). In the children infected with RSV, in constrast to those with influenza, interferon detection was not associated with diminished shedding of virus.     

Concurrent outbreaks of rhinovirus and respiratory syncytial virus in an intensive care nursery: epidemiology and associated risk factors

An outbreak of viral respiratory disease occurred in eight infants in a neonatal intensive care unit during the 1980 winter respiratory season. Four infections with respiratory syncytial virus and four infections with rhinovirus were identified. Epidemiologic investigation revealed that viral respiratory infection was significantly associated with intubation with orotracheal tubes (P = 0.001), with the presence of both a nasal feeding tube plus an orotracheal tube together (P = 0.007), and with assisted ventilation (P = 0.009) when compared to uninfected controls. Twenty-seven of 85 (30.6%) personnel working in the unit at the time of the outbreak reported a history of upper respiratory illness during the week prior to the outbreak, and 46 (54.1%) of them had had contact with patients in areas of the hospital where patients infected with RSV and rhinovirus were housed. The data suggest that both viruses were transmitted to the babies by hospital personnel. Rhinoviruses can be nosocomial pathogen in neonates with compromised pulmonary function, and the clinical presentation of rhinovirus infection in neonates may be difficult to distinguish from that produced by RSV.     

Respiratory syncytial virus infections in infants: quantitation and duration of shedding.

Infants hospitalized with respiratory syncytial virus infection were studied to delineate the quantitative shedding patterns and duration of shedding of RSV. Nasal wash specimens collected daily from 19 infants contained a mean maximal titer of 4.34 log10 50% tissue culture infective doses per milliliter. On admission, the mean titer was 4.14 log10 TCID50, with no consistent decline until after Day 6. The mean duration of shedding for 23 patients until they were virus negative was 6.7 days with a range of 1 to 21 days. Quantities of RSV shed were significantly greater in infants less than one month of age and in infants with evidence of pulmonary consolidation on chest roentgenogram. Shedding extended for a significantly longer time in infants with lower respiratory tract disease than in those with clinical manifestations limited to the upper respiratory tract.     

Parainfluenza viral infections in children: correlation of shedding with clinical manifestations.

Children presenting with acute respiratory disease to a private group practice in the fall of 1975 were studied to: (1) evaluate the efficacy in a pediatric office of a simple technics of obtaining nasal washes for the diagnosis of parainfluenza virus infections and (2) to determine the quantities of virus shed in relation to clinical characteristics. The nasal wash technic proved feasible for an office or clinic. Parainfluenza virus type 1 was recovered from 26 (74%) of 35 children with croup and from 40 (56%) of the total 72 children presenting with any form of respiratory illness. Virus was recovered significantly more often from children with croup and from those of younger age. The mean quantity of virus in 26 nasal washes was 2.97 log10 TCID50/ml. The shedding of greater quantities was correlated with younger age and the more frequent occurrence of laryngitis, pharyngitis, and fever.