We compared pneumococcal isolation rates and evaluated the benefit of using oropharyngeal (OP) specimens in addition to nasopharyngeal (NP) specimens collected from adults in rural Kenya. Of 846 adults, 52.1% were colonized; pneumococci were detected from both NP and OP specimens in 23.5%, NP only in 22.9%, and OP only in 5.7%. Ten-valent pneumococcal conjugate vaccine strains were detected from both NP and OP in 3.4%, NP only in 4.1%, and OP only in 0.7%. Inclusion of OP swabs increased carriage detection by 5.7%; however, the added cost of collecting and processing OP specimens may justify exclusion from future carriage studies among adults.

BACKGROUND: Vaccination of children with 13-valent pneumococcal conjugate vaccine (PCV13) led to declines in vaccine-type pneumococcal nasopharyngeal carriage among adults through indirect effects. In August 2014, PCV13 immunization of all U.S. adults >/=65years of age was recommended. This study sought to define prevalence and serotype distribution of pneumococcal carriage among adults >/=65years of age and to describe risk factors for colonization soon after introduction of PCV13 in adults. METHODS: A cross-sectional survey of non-institutionalized U.S. adults >/=65years of age was conducted in four states in 2015-2016. Demographic information, risk factors for disease, PCV13 vaccination history, and nasopharyngeal (NP) and oropharyngeal (OP) swabs were collected. NP and OP swabs were processed separately and pneumococcal isolates were serotyped by Quellung reaction. Antimicrobial susceptibility of pneumococcal isolates was performed. NP swabs also underwent real-time PCR for pneumococcal detection and serotyping. RESULTS: Of 2989 participants, 45.3% (1354/2989) had been vaccinated with PCV13. Fifty-five (1.8%) carried pneumococcus (45 identified by culture and 10 by real-time PCR only) and PCV13 serotypes were found in eight (0.3%) participants. Almost half (22/45) of pneumococcal isolates were not susceptible to at least one of the antibiotics tested. Vaccine-type carriage among vaccinated and unvaccinated individuals was similar (0.2% vs. 0.1%, respectively). Respiratory symptoms were associated with higher odds of pneumococcal colonization (adjusted OR: 2.1; 95% CI=1.1-3.8). CONCLUSIONS: Pneumococcal carriage among non-institutionalized adults >/=65years of age was very low. Less than 0.5% of both vaccinated and unvaccinated individuals in our study carried vaccine-type serotypes. Over a decade of PCV vaccination of children likely led to indirect effects in adults. However, given the low vaccine-type carriage rates we observed in an already high PCV13 adult coverage setting, it is difficult to attribute our findings to the direct versus indirect effects of PCV13 on adult carriage.

Polymerase chain reaction-based surveillance for bacterial meningitis including 841 children revealed 246 with bacterial DNA in cerebrospinal fluid samples of which 53% were Streptococcus pneumoniae, 19% Neisseria meningitidis, and 16% Haemophilus influenzae type b. The most common S. pneumoniae serotypes/serogroups were 1, 19F, 6A/6B, 23F, 5, 14, 18 and 19A. Among 47 meningococci, 86% were serogroup B, 6% serogroup C, 3% serogroup A, 3% serogroup X and 3% serogroup W.

OBJECTIVE: Haemophilus influenzae type b (Hib) conjugate vaccine has dramatically reduced invasive Hib disease worldwide. Yet, data on protection against pneumonia and among children with HIV are limited. We evaluated the impact of Hib conjugate vaccine introduction in 2009 in a rural, high-HIV prevalence area in Mozambique. STUDY DESIGN: From 2006-2011, we conducted hospital-based surveillance for invasive Hib disease and clinical pneumonia (classified as severe and very severe) among children <5 years of age. Incidences calculated using population denominators were compared between baseline (2006-2008) and post-Hib conjugate vaccine (2010-2011) periods. Surveillance data for radiologically-confirmed pneumonia among children <2 years of age in 2011 were compared with baseline data from 2004-2006. RESULTS: Among 50 cases of invasive Hib disease, 5 occurred after Hib conjugate vaccine introduction; 1 case-patient was age-eligible for Hib conjugate vaccine (and had received 3 doses). Four post-Hib conjugate vaccine case-patients (including Hib conjugate vaccine failure) had HIV. Among children <1 and <5 years of age, significant reductions occurred in rates of invasive Hib disease (91% and 85%, respectively) and very severe pneumonia (29% and 34%, respectively). Radiologically-confirmed pneumonia incidence fell significantly (33%) in children <2 years of age. Severe pneumonia incidence did not decline. CONCLUSIONS: We demonstrate important reductions in invasive disease and pneumonia following Hib conjugate vaccine introduction in a high-HIV area. Continued surveillance is needed to monitor long-term Hib conjugate vaccine effects, particularly among children with HIV.

OBJECTIVES: Bacterial meningitis is associated with high mortality and long-term complications. This study assessed the impact of Haemophilus influenzae type b (Hib) conjugate vaccine on childhood bacterial meningitis in Ulaanbaatar, Mongolia. STUDY DESIGN: Prospective, active, population-based surveillance for suspected meningitis in children aged 2-59 months was conducted (February 2002-January 2011) in 6 hospitals. Clinical data, blood, and cerebrospinal fluid were collected. The impact of Hib conjugate vaccine was assessed by comparing Hib and all cause meningitis data in the 3 years preceding pentavalent conjugate vaccine implementation (2002-2004) with 3 years postimplementation (2008-2010). RESULTS: Five hundred eleven cases of suspected meningitis were identified from 2002-2011. Pentavalent conjugate vaccine coverage in December 2005 in Ulaanbaatar city was 97%. The proportion of suspected cases confirmed as Hib meningitis decreased from 25% (50/201) in the prevaccination era to 2% (4/193) in the postvaccination era (P < .0001). The annual incidence of Hib decreased from 28 cases per 100 000 children in 2002-2005 to 2 per 100 000 in 2008-2010 (P < .0001). CONCLUSIONS: This article demonstrates the marked impact of Hib conjugate vaccine introduction on meningitis in Mongolia. It is important to sustain this surveillance system to monitor the long-term impact of Hib conjugate vaccine, as well as other interventions such as pneumococcal and meningococcal vaccines.

We developed and validated a real-time PCR assay consisting of 7 triplexed reactions to identify 11 individual serotypes plus 10 small serogroups representing the majority of disease-causing isolates of Streptococcus pneumoniae. This assay targets the 13 serotypes included within the 13-valent conjugate vaccine and 8 additional key serotypes or serogroups. Advantages over other serotyping assays are described. The assay will be expanded to 40 serotypes/serogroups. We will provide periodic updates at our protocol web site.

During a pneumococcal disease outbreak in a pediatric psychiatric unit in a hospital in Rhode Island, USA, 6 (30%) of 20 patients and staff were colonized with Streptococcus pneumoniae serotype 15A, which is not included in pneumococcal vaccines. The outbreak subsided after implementation of antimicrobial drug prophylaxis and enhanced infection control measures.

Pneumococcal nasopharyngeal carriage isolates recovered from Brazilian children attending day-care centres in 2005 were assessed for serotype, genotype and penicillin susceptibility phenotype. As 124 of the 253 isolates (49 %) were characterized previously with respect to serotype and penicillin susceptibility, the primary objectives were to examine clonal associations and penicillin susceptibility within major serotypes and to assess the suitability of conventional multiplex PCR for deducing carriage serotypes within this population. Using a combination of PCR-based serotyping and the Quellung reaction, serotypes were identified for 81 % (205/253) of the isolates, with serogroups or types 14, 6, 23F, 19F and 18 being predominant. Included within the 205 isolates successfully serotyped by PCR were 28 isolates that had become non-viable. Forty-eight isolates were non-typable using both the PCR method and the Quellung reaction. Penicillin non-susceptibility was observed within 16 of the 18 multilocus sequence types detected. Thus, this study provides further evidence from a diverse collection of pneumococcal clones that PCR-based serotype deduction is useful for providing supportive evidence for pneumococcal conjugate vaccine implementation.

According to population-based invasive pneumococcal surveillance in the United States during 2007, 898 (26%) of 3,511 isolates were penicillin nonsusceptible. Non-7-valent pneumococcal conjugate vaccine (PCV7) serotypes other than 19A accounted for 40% of these penicillin-nonsusceptible isolates; of these, serotypes 15A (11%), 23A (8%), 35B (8%), and 6C (5%) were most common (cumulatively 32% of penicillin-nonsusceptible isolates). Each except 6C represented a single serotype and clonal complex combination that predated the introduction of PCV7. We evaluated the genetic characteristics and nonsusceptibility to penicillin of non- PCV7 serotypes, and we found increased proportions of specific penicillin-nonsusceptible clones in serotypes 15A, 23A, 35B, and 6C, which potentially indicates a basic change of population structure within these individual serotypes.