BackgroundThe bacteria Streptococcus pneumoniae (pneumococcus) and Haemophilus influenzae type b (Hib) are leading causes of childhood pneumonia and meningitis and are major contributors to worldwide mortality in children younger than 5 years of age. Asymptomatic nasopharyngeal carriage of pneumococcus and Hib was determined for healthy children in Shanghai in 2009.MethodsChildren from 5 immunization clinics were enrolled in this study. Specimens from the nasopharynx were collected and cultured in Columbia and chocolate agar to identify pneumococcal and Hib carriage. Pneumococcal specimens were serotyped with the Neufeld test, and antibiotic resistance for pneumococcal and Hib specimens used the E-test method. Significance of risk factors for carriage was assessed through chi-square tests.ResultsAmong 614 children, 16.6 % had pneumococcal carriage and 8.0 % Hib carriage. The predominant serotype of pneumococcus that was isolated was 19 F (52.9 %); serotype coverage was 68.6 % for both 7-valent pneumococcal conjugate vaccine (PCV) and PCV-10, and 82.3 % for PCV-13. Household residency and father’s education were both significantly related to pneumococcal and Hib carriage. The majority of S. pneumoniae isolates were sensitive to most antimicrobials but there were high levels of resistance to azithromycin (51.0 %) and erythromycin (51.0 %). Haemophilus influenzae isolates were sensitive to almost all antimicrobials tested although 12.2 % of isolates were resistant to ampicillin.ConclusionsThe pneumococcal and Hib vaccines require payment, and the children with the highest burden of disease may not be receiving these vaccines. Moreover, the presence of high antibiotic susceptibility towards pneumococcus, and to a lesser extent towards Hib, underscores the need for preventive protection against these diseases. Public funding of pneumococcal and Hib vaccines would be one mechanism to increase uptake of these vaccines.

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Growth of cubic normalSiC has been carried out on Si (111) and (100) substrates and on 6H‐normalSiC Lely crystals using chemical vapor deposition at atmospheric pressure. Hexamethyldisilane (HMDS) was used as the only precursor and pure Ar or a nonflammable mixture of 4% H2 in Ar was used as the carrier gas. The crystallinity was characterized by x‐ray diffraction and transmission electron microscopy, while the stoichiometry was revealed by Auger electron spectrometry (AES). It was found that polycrystalline layers were obtained at low growth temperatures and with pure Ar as the carrier gas, while the crystallinity improved at temperatures above 1300°C and when H2 was added. Under optimum growth conditions most of the grains are oriented with parallel epitaxy or with twinned epitaxy with respect to the substrate. In every case, however, there are some grains which are randomly oriented. The AES data show carbon accumulation on the surface of thick normalSiC layers. It is thought that the major problem in growing single‐crystalline normalSiC with HMDS in a H2‐normalpoor atmosphere is the presence of excess carbon.