Penicillin resistance and serotype distribution of Streptococcus pneumoniae in nasopharyngeal carrier children under 5 years of age in Dar es Salaam, Tanzania

Abstract

This study aimed to determine the magnitude of nasopharyngeal carriage, antimicrobial resistance and serotype distribution of Streptococcus pneumoniae in healthy children under 5 years of age in Tanzania. Nasopharyngeal swabs were obtained from 300 healthy children attending a child health clinic at Muhimbili National Hospital in Dar es Salaam, Tanzania. S. pneumoniae was isolated and identified using conventional methods. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disc diffusion method. Penicillin MICs and serotypes were determined by an agar gradient diffusion method and the Quellung reaction, respectively. A total of 105 samples (35 .0%) were positive for S. pneumoniae and 115 serotypes were detected (ten specimens yielded two serotypes each). Overall, 78 of 115 isolates (67.8 %) were penicillin-non-susceptible pneumococci (PNSP). The resistance levels of S. pneumoniae to trimethoprim-sulfamethoxazole, tetracycline, erythromycin, chloramphenicol and ceftriaxone were 82.6, 10.4, 6.0, 3.5 and 0.0 %, respectively. Multidrug resistance was detected in 19 isolates (16.5 %). The most prevalent serotypes were 19F (n525, 21.7 %), 6B (n515, 13.0 %), 9V (n514, 12.2 %) and 13 (n514, 12.2 %). Of the 64 pneumococcal isolates potentially covered by the seven-valent pneumococcal conjugate vaccine (PCV7), 44 (68.8 %) were PNSP. A high prevalence of PNSP, common pneumococcal serotypes circulating worldwide, was found, and many of the resistant pneumococci strains are covered by the PCV7. These findings indicate that the carriage rate of such resistant strains could be influenced by an appropriate vaccination programme in the study setting and by reinforcing regulations on the rational use of antimicrobial agents.

Penicillin resistance and serotype distribution of Streptococcus pneumoniaein Ghanaian children less than six years of age

“…This difference might be due to the age differences between our study subjects (≤6 years of age) and those of the previous study, which included children ≤13 years of age [18]. The overall carriage in our study was relatively low when compared with prevalence rates reported in other African countries; 22%-60% in Kenya [22,23], 62% in Uganda [24], 90% in Gambia [25] and 35% in Tanzania [26]. This may be due to the low numbers of children below the age of two years included in this study (Table 1).…”

Carriage of Streptococcus pneumoniae and Other Respiratory Bacterial Pathogens in Low and Lower-Middle Income Countries: A Systematic Review and Meta-Analysis

“…In addition, NVT were acquired faster (median age at acquisition, 152 days vs. 174; p = 0.004) and had a shorter duration of carriage (median duration, 43 vs. 70 days; p<0.001) than PCV7-serotypes [50]. Between 36% and 56% of the pneumococcal isolates detected in unvaccinated healthy children <5 years of age in Africa were of PCV-7 serotypes [50], [51], [57], [63], [64], whereas the proportions were 37%–56% for PHiD-CV (10-valent pneumococcal Haemophilus influenzae protein D conjugate vaccine) and 50%–64% for PCV-13 (13-valent pneumococcal conjugate vaccine) [51], [63]. Non-typeable S. pneumoniae represented between 0.7% [55] and 20.6% [60] of the isolates.…”

“…The pooled prevalence for carriage o f S. pneumoniae in healthy children <5 years of age was 64.8% (95% CI, 49.8%–76.1%) for the five populations from low income countries [52], [53], [55], [63], [65] and 47.8% (95% CI, 44.7%–50.8%) for the six populations from lower-middle income countries (Figure 2) [36], [56], [66]–[69]. However, studies were highly heterogeneous in the low income countries (I 2  = 98%), in contrast to those in the lower-middle income countries (I 2  = 0%).…”

Avaliação dos efeitos da inflamação na infecção respiratória por<i> Streptococcus</i> <i>pneumoniae</i> em camundongos.

“…(Constenla, 2008). O uso de agentes antimicrobianos está entre as principais estratégias de combate as infecções pneumocócicas, porém a dificuldade em estabelecer um tratamento eficaz é devido ao surgimento de cepas resistentes a antibióticos, principalmente ß-lactâmicos (Kim et al, 2012;Moyo et al, 2012).…”