Oro-Pharyngeal Carriage And Antimicrobial Susceptibility Of Streptococcus Pneumoniae From Healthy Children
Z Rashid, I Isahak, C Jeann, M Suki, N Mohamad, D Hussain, T Sim, H Jaafar, Y Yusof, M Rahman
antimicrobial susceptibility, children, colonisation, oropharyngeal carriage, serotype, streptococcus pneumoniae
Z Rashid, I Isahak, C Jeann, M Suki, N Mohamad, D Hussain, T Sim, H Jaafar, Y Yusof, M Rahman. Oro-Pharyngeal Carriage And Antimicrobial Susceptibility Of Streptococcus Pneumoniae From Healthy Children. The Internet Journal of Microbiology. 2013 Volume 11 Number 1.
Colonisation of the upper respiratory tract is the prerequisite for the development of infection and invasive pneumococcal disease. Epidemiology studies in western countries had shown a significant correlation between invasive pneumococcal disease in children with identification of asymptomatic carrier of
Recent years resistance of
The aim of this study was to determine the prevalence and antimicrobial susceptibility of
Materials and Methods
This cross-sectional study was conducted in the daycare nursery of Universiti Kebangsaan Malaysia Medical Centre (UKMMC) and Tengku Budriah Orphanage, Jalan Yaakob Latif, Kuala Lumpur
Children in ‘open community’ were those who attended the UKMMC daycare nursery during office hours. They were exposed to family members at home, other children and staff in the nursery. The children from the UKMMC daycare nursery age ranged between birth to 4 years old, and they were cared for by their parents after working hours. Children in ‘closed community’ were children who lived together in the same place and had less exposure or contact hours with the outside community. Tengku Budriah Orphanage is a government-managed orphanage under the Department of Social Welfare and the Ministry of Women, Family and Community Development, Malaysia. It adopts and provides shelter to children with problematic socio-economic background. These children stay full time in the centre, while attending the kindergarten set up within the orphanage.
Five final year medical students were involved in conducting this study, and were trained by Otorhinolaryngology surgeons in this centre on the correct throat swab procedure. Throat swabs were taken from all healthy children aged between birth to 6 years old after obtaining informed consents from the parents or the authorities of Department of Social Welfare, Malaysia. Sterile swabs were used to collect the samples from their oropharynx, and with the assistance of microbiologists the specimens were inoculated immediately onto 5% sheep blood agar plates and transported in a cooler box to the laboratory.
In the laboratory, the plates were streaked and incubated in 5% CO2 incubator at 37°C for 20-24 hours. The isolation and identification of
Data was analyzed using SPSS version 13.0. Percentages of oropharyngeal carriage of
A total of 120 children were included, where 84 were from the orphanage and 36 were from the daycare nursery. The mean age of these children was 30.8 months, where the oldest was 74 months old and the youngest was 2 weeks old. The demographics of the children are shown in Table 1. There were 64 males and 56 females (53.3% and 46.7% respectively). The children were of different ethnicity, namely Malay (78.8%), Indian (11.0%), Chinese (3.4%), and others (6.8%).
Serotyping showed serotype 11F for one isolate, while the other isolate was non-typable. Both isolates were susceptible to penicillin, and the MIC was 0.006 µg/mL (serotype 11F isolate) and 0.125 µg/mL (non-typable isolate). The serotype 11F isolate was susceptible while the non-typable isolate was resistant to erythromycin. The full antibiotic susceptibility results by disk diffusion method are shown in Table 3, and MIC results are shown in Table 4.
This was a community-based study in Malaysia. The results showed that the prevalence of
The colonisation rates of
The method used to obtain our oropharyngeal specimens for the isolation of
Although the results showed that there was no significant correlation between the age group of children and the prevalence of
The findings showed that there was a higher prevalence of carrier rate in the daycare centre or nursery compared to Tengku Budriah orphanage could mean that the children with more exposure to the community could be more susceptible to colonisation.
Limitations in our study include the small sample size, a total of 120 children up to age of 6 years. The study was conducted in a short span of time with a single sampling session. A likely explanation for the low prevalence in our population compared to other studies could also be attributed to the sampling method used, with the lower sensitivity of oropharyngeal compared to nasopharyngeal specimens.
Both our isolates were sensitive to penicillin. The serotype 11F isolate was susceptible while the non-typable isolate was resistant to erythromycin, while both were susceptible to azithromycin. The rate of penicillin-nonsusceptible
Approved vaccines for pneumococcal infections contained 23 serotypes (polysaccharide vaccine, PPV23), 7 and 10 serotypes (pneumococcal conjugate vaccines, PCV7 and PCV10). A recently approved 13-valent pneumococcal vaccine (PCV13) now succeeds PCV7 which has been used in routine childhood immunization schedule in several countries, such as the United States since 2000.29 PCV13 contains six other serotypes (1, 3, 5, 6A, 7F and 19A) in addition to the seven serotypes in PCV7 (4, 6B, 9V, 14, 18C, 19F and 23F).
Based on previous studies, serotype 11F has never been reported in Malaysia.3,4,9,11 Surveillance S
The results demonstrated a low prevalence of
This study was conducted with the grant from UKMMC Fundamental Research Fund, project code FF-158-2010. Authors are thankful to Director of the Department of Social Welfare, Principal of Government-managed orphanage and Principal of UKMMC Nursery. Authors are also thankful to Otorhinolaryngology surgeons, Mr Jeevanan Jahendran and Dr Mohd Iszuari Md Ismail who had trained the five medical students the technique of obtaining oropharyngeal specimens via throat swab. Authors are grateful to Dr Rohaidah Hashim, Bacteriology Unit, Institute of Medical Research, Kuala Lumpur for assistance in serotyping the isolates. Authors acknowledge the help of laboratory technologist Sukeri Kasni, postgraduate students Dr Adilahtul Bushro Zaini and Dr Hasni Mahayidin, and Infection Control Nurse Nor Rina Mahawar, during the study.