High rate of antibiotic resistance among pneumococci carried by healthy children in the eastern part of the Democratic Republic of the Congo

Abstract

BackgroundPneumococcal conjugate vaccines have been introduced in the infant immunisation programmes in many countries to reduce the rate of fatal pneumococcal infections. In the Democratic Republic of the Congo (DR Congo) a 13-valent vaccine (PCV13) was introduced in 2013. Data on the burden of circulating pneumococci among children after this introduction are lacking. In this study, we aimed to determine the risk factors related to pneumococcal carriage in healthy Congolese children after the vaccine introduction and to assess the antibiotic resistance rates and serotype distribution among the isolated pneumococci.MethodsIn 2014 and 2015, 794 healthy children aged one to 60 months attending health centres in the eastern part of DR Congo for immunisation or growth monitoring were included in the study. Data on socio-demographic and medical factors were collected by interviews with the children’s caregivers. Nasopharyngeal swabs were obtained from all the children for bacterial culture, and isolated pneumococci were further tested for antimicrobial resistance using disc diffusion tests and, when indicated, minimal inhibitory concentration (MIC) determination, and for serotype/serogroup by molecular testing.ResultsThe pneumococcal detection rate was 21%, being higher among children who had not received PCV13 vaccination, lived in rural areas, had an enclosed kitchen, were malnourished or presented with fever (p value < 0.05). The predominant serotypes were 19F, 11, 6A/B/C/D and 10A. More than 50% of the pneumococcal isolates belonged to a serotype/serogroup not included in PCV13.Eighty per cent of the isolates were not susceptible to benzylpenicillin and non-susceptibility to ampicillin and ceftriaxone was also high (42 and 37% respectively). Almost all the isolates (94%) were resistant to trimethoprim-sulphamethoxazole, while 43% of the strains were resistant to ≥3 antibiotics.ConclusionsOur study shows alarmingly high levels of reduced susceptibility to commonly used antibiotics in pneumococci carried by healthy Congolese children. This highlights the importance of local antibiotic resistance surveillance and indicates the needs for the more appropriate use of antibiotics in the area. The results further indicate that improved living conditions are needed to reduce the pneumococcal burden, in addition to PCV13 vaccination.Electronic supplementary materialThe online version of this article (10.1186/s12887-018-1332-3) contains supplementary material, which is available to authorized users.

Pathogens in the upper respiratory tract of Congolese children with radiologically confirmed pneumonia

“…Fifteen years ago, it was found that trimethoprim-sulfamethoxazole and amoxicillin were frequently used in self-medication in Congolese children having cough with or without fever [5]. We have recently showed a high level of resistance against trimethoprim-sulfamethoxazole in pneumococci colonizing healthy children in this area of DR Congo [18] and similar results were shown for healthy children in northern Tanzania [37]. Here we found that pre-hospitalisation medication by the peroral broad spectrum antibiotic trimethoprimsulfamethoxazole was more common in children with severe pneumonia than in children with nonsevere disease, and pre-hospitalisation treatment with trimethoprim-sulfamethoxazole was also associated with fatal outcome.…”

“…A nasopharyngeal specimen was obtained from all included children using an Eswab (Copan Diagnostics Inc., Murrieta, CA), following a standardised procedure as previously described [18]. The samples were shipped immediately to the Clinical Laboratory at Panzi Hospital for subsequent pneumococcal culture as described earlier [18].…”

“…A nasopharyngeal specimen was obtained from all included children using an Eswab (Copan Diagnostics Inc., Murrieta, CA), following a standardised procedure as previously described [18]. The samples were shipped immediately to the Clinical Laboratory at Panzi Hospital for subsequent pneumococcal culture as described earlier [18]. The nasopharyngeal samples were thereafter stored frozen at -20 °C before shipment to the Department of Infectious Diseases, University of Gothenburg, Gothenburg, Sweden, for further molecular analyses (see below).…”

“…Increased knowledge surrounding the clinical presentation and pathogens present in children with acute pneumonia may improve future clinical management and prevention of the infection, not least in low-income settings such as DR Congo which not only has a high disease burden [2] but also high rates of antibiotic resistance in the pneumococci colonizing young children [18]. In DR Congo the antibiotic treatments available are entirely empiric due to insufficient microbiological diagnostics and, to our knowledge no studies exist which have assessed the burden of respiratory pathogens in children hospitalized due to acute respiratory infection.…”

Carriage of penicillin-non-susceptible pneumococci among children in northern Tanzania in the 13-valent pneumococcal vaccine era

“…Initially, the detection of 40 different serotypes was performed using a multiplex real-time PCR protocol published by the US Centers for Disease Control and Prevention (CDC) with slight modifications, as described previously (Birindwa et al, 2018). For cpsA-positive samples in which the serotype could not be detected by the multiplex PCR, the serotypes/serogroups were determined using a modified Sequetyping protocol (Birindwa et al, 2018). Briefly, two PCR reactions were set up to amplify the whole cpsB gene.…”