This investigation describes the development of a solid and a liquid medium (Gonococcal Genetic Medium; GGM) which support the rapid growth of 41 gonococcal clinical isolates and laboratory strains with a minimum number of nutritional components. The complete medium contains minimal salts, eight amino acids, two nitrogen bases, vitamins, coenzymes, key metabolic intermediates, and some miscellaneous components. Results indicate that GGM can be modified and simplified even further than we described. In liquid GGM, several gonococcal strains grew logarithmically after a 2-to 3-h lag period with generation times ranging from 72 to 115 min, reaching optical densities of 175 to 320 Klett units in the presence of seven amino acids and in the absence of a CO2 atmosphere. The development of a solid and a liquid defined minimal medium such as GGM should greatly broaden the avenues of experimentation for biochemical genetic studies with N. gonorrhoeae, especially gonococcal genetic transformation. N. gonorrhoeae can be classified into eight major and minor phenotypic groups, depending on its growth responses on GGM to just five amino acids: cysteine and cystine, arginine, proline, isoleucine, and serine. Such results demonstrate the feasibility of using GGM as a simple, sensitive, rapid probe for investigating the epidemiological patterns of gonorrhea.

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Abstract:The relationship between feeding method and risk of rotavirus infection was studied by following a cohort of 197 infants from low income households through the winter diarrhea season of 1983-84. Fecal specimens were systematically collected and tested for the presence of rotavirus particles by electron microscopy, confirmed by ELISA. The attack rates of rotavirus gastroenteritis were similar for breast-fed and bottle-fed infants (20 per cent, 17 per cent, respectively); however, the clinical course of rotavirus gastroenteritis was quite different. Infants who were breast-fed had IntroductionBoth nutritional and immunologic properties of human milk make it the preferred diet for infants. While there is consistent epidemiologic evidence to suggest that infants fed breast milk are at lower risk of enteric illness caused by bacterial agents, the evidence for viral-related gastroenteritis

Cerebrospinal fluid (CSF) specimens from pediatric patients with meningitis were examined for their concentration of microbes and the relationship of this count to the bacteremia levels, microscopy results, and polymorphonuclear leukocyte concentration. A total of 2,031 consecutive CSF specimens were analyzed, of which 63 (3.1%) were positive by culture from the same number of patients. We observed that 85% of the total CSF specimens positive for Haemophilus influenza type b, Streptococcus agalactiae, Streptococcus pneumoniae, and Neisseria meningitidis had counts in excess of 103 CFU/mI, with 56% of the specimens exceeding 105 CFU/ml. A correlation existed between the number of organisms present in the CSF and blood. For example, from a total of 22 patients who had counts of H. influenza >î03 CFU/ml in the CSF, 16 or 73% had levels of bacteremia >103 CFU/ml. It was also noted that the bacterial concentration had a profound effect on the sensitivity of microscopy. The percentage of positive results increased from 25% with sO03 CFU/ml to 60% in the range of >103 to 105 CFU/ml and to 97% at concentrations of >105 CFU/ml. Furthermore, a significant correlation (P < 0.01) was noted between the concentration of bacteria in the CSF and the number of polymorphonuclear leukocytes observed on microscopy.

During a 1-year period, three bacteriological systems for detecting bacteremia in children were analyzed, namely, the BACTEC system (Johnston Laboratories, Inc., Cockeysville, Md.), the Fisher/Lederle bottle (Lederle Diagnostics, Pearl River, N.Y.), and a direct plating method of blood, termed quantitative direct plating (QDP). Of 2,123 blood cultures, 135 (6.4%) were positive; Haemophilus influenza type b, Neisseria meningitidis, and Streptococcus pneumoniae accounted for 3.4%, representing 61 patients, other pathogens accounted for 0.6%, and contaminants accounted for 2.4%. Of 72 cultures yielding H. influenza, N. meningitidis, and S. pneumoniae, 60 were recovered by both broth systems, 2 by BACTEC only and 10 by Fisher/Lederle bottle only. The BACTEC system failed to register a positive growth index reading by 24 h in 15 cultures which were positive for H. influenza, even though growth had occurred, as shown by positive subculture and microscopy at this time. QDP detected 89% of the cultures positive for H. influenza and N. meningitidis, of which 55% yielded results before either broth procedure. Only 50% of the cultures positive for S. pneumoniae yielded growth on QDP. This difference in the recovery rates probably is accounted for by the number of organisms in the blood. Thus, more than 100 organisms per mI of blood were found in 71% of cultures positive for H. influenza and N. meningitidis but in only 7% of those positive for S. pneumoniae. These studies, then, have revealed that H. influenza, which grew well in BACTEC broth, did not, however, give a significant growth index reading during day 1 of incubation, in contrast to N. meningitidis and S. pneumoniae. The QDP system not only provided information on the magnitude of bacteremia due to H. influenza and N. meningitidis but frequently allowed earlier diagnosis and, thus, proved to be a valuable, simple, and inexpensive supplementary technique for broth cultures, although not for the diagnosis of S. pneumoniae bacteremia.