Pneumococcal Carriage and Serotype Distribution in Children With Otitis Media in Malaysia.

Overview

The purpose of this research is to conduct a multi-center prospective surveillance study focusing upon pneumococcal carriage and serotype epidemiology in patients with otitis media (OM).The data generated will be crucial especially as baseline data for future assessments on the long-term impacts of pneumococcal conjugate vaccine 10 (PCV10) coverage, compared to that of pneumococcal conjugate vaccine 13 (PCV13) that is being used in the majority of other countries. Pneumococcal carriage in patients with OM and serotype distribution will be assessed, including changes in antibiotic resistance. With the establishment of sentinel surveillance in the country, we hope to provide detailed data on the epidemiology of OM in Malaysia; working towards the development of a national surveillance programme for the monitoring of OM burden in the country.

Otitis media (OM) is a condition defined as an inflammation of the middle ear and is one of the most commonly diagnosed infections in children, especially amongst those aged below 5 years (1). By 3 years of age, approximately 80% of children have experienced at least one episode of acute otitis media (AOM) in developed countries. More than 700 million AOM cases are reported annually worldwide at an incidence rate of 10.8%, with Southeast Asia reporting a yearly incidence of 8.2% and disease burden varying substantially by geographical location (2). In Malaysia, based on data published from a population based survey (n=7,041) conducted by the Ministry of Health in 2005 (3),OM with effusion (OME) prevalence was found to be 2.9% amongst individuals all ages, of which 46.5% suffered from hearing loss. Amongst children, OME prevalence was 3.8% in those aged ≤17 years, 1.4% in 13-17 year olds and 2.3% in children ≤12 years of age. The survey also found that prevalence was higher in rural settings (3.2%) compared to urban settings (2.7%). These findings were in contrast to an earlier cross-sectional study based on 5 to 6 years olds from kindergartens in 1993 (n=1,097), where prevalence was 17.9% in the urban district of Kuala Lumpur compared to 9.5% in rural Kuala Selangor (4). AOM was found in Malaysia to have a negative impact on both parental and child quality of life (QoL), with significant indirect healthcare costs and thus substantial economic burden in the population (5). Studies on the epidemiology of AOM, especially those reliant upon clinical diagnosis and following the uptake of pneumococcal conjugate vaccination (PCV) are few and far between. In Malaysia the prevalence of OME, as described above, has been reported although limited to specific settings and locations, with even fewer assessments on AOM prevalence. Immunisation programmes against Spn have an impact on carriage, and consequently the causative pathogen and infecting strains of Spn in OM infections. There has been a consistent observed association between PCV introduction and a decline of AOM infections caused by Spn. As Malaysia is one of the more recent countries to start the PCV National Immunisation Programme (NIP), this presents an excellent opportunity to begin surveillance on pneumococcal carriage and serotype distribution allowing for a detailed assessment of the epidemiology of OM in the country. Specific Objectives 1. To determine the prevalence of Streptococcus pneumoniae (Spn) nasopharyngeal carriage among children 5 years of age and below with OM 2. To determine Spn serotypes in children diagnosed with OM