Microbiology and paediatric research
Microbiology and non-malaria child health research at SMRU is conducted mainly in Maela camp. Current research themes are focussed on epidemiological studies of acute respiratory infection and neonatal sepsis.
Pneumonia
Pneumonia is the leading cause of childhood mortality (outside of the neonatal period) in the developing world, with an estimated two million children dying each year. The epidemiology of pneumonia in rural SE Asia is poorly defined.
SMRU is currently undertaking a longitudinal cohort study, following one thousand infants born in Maela from birth until the age of two years. The aims of the study are to determine the incidence, causes, and outcomes of pneumonia in infancy. Infants are seen in the clinic where blood and respiratory specimens are collected when pneumonia is diagnosed and a chest x-ray is performed. Babies are diagnosed and treated using standard WHO protocols.
The main pathogens of interest are bacteria (Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus) and viruses (human metapneumovirus, influenza viruses, and respiratory syncitial virus).
The nasopharynx is the reservoir of the commonest bacterial respiratory pathogen, Streptococcus pneumoniae. Infants are frequently colonised with this bacterium, but the natural history, outcomes, and modulators of this colonisation are incompletely understood. As part of the cohort study, each infant undergoes nasopharyngeal swabbing each month to determine carriage status and, in a sub-group, a monthly blood sample is also collected to monitor the development of anti-pneumococcal antibody levels.
Influenza surveillance
In partnership with the US Centers for Disease Control (US-CDC) SMRU undertakes acute respiratory infection surveillance in Maela. Patients presenting with influenza-like illness or pneumonia undergo virological testing to determine the burden of influenza virus infection in the refugee population. The surveillance also acts as an early warning system to detect outbreaks of unusual respiratory infections.
Neonatal sepsis
Four million neonates die a year, the majority in the developing world from sepsis. Little is know about the aetiology of such cases. In the developed world Group B Streptococcus (GBS) is the most common causative organism. Maternal vaginal or rectal carriage of GBS is a prerequesite for newborn infection. Neonatal GBS infection may be less common in many developing world areas, but the causes for this discrepancy are not well undertood since maternal carriage rates are similar in most regions of the world.
SMRU is about to commence a study in Maela to define both the maternal GBS carriage rates, and the burden of GBS in newborn infections in this population, with the long term goal of the introduction of prevention strategies. The study has two components:
The GBS carriage study, in which vaginal-rectal swabs of 500 women following antenatal care at the SMRU clinic in order to calculate GBS carriage rate. GBS isolates will be sero-typed and the antibiotic sensitivities established. Maternal and cord blood will be taken to determine the prevalence of serum antibodies to common GBS capsular serotypes in the pregnant women, the influence of carriage on serotype (ST)-specific antibody and the ST-specific antibody concentrations in the mothers of cases of confirmed and clinical GBS disease.
The study of neonatal sepsis, which comprises treatment and investigation of 200 newborn infants with sepsis, with the aim of establishing the aetiology for each case.
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