By: Emily Robie, MSc
As a clinician at Kapit Hospital in Sarawak, Malaysia, Dr. King-Ching Hii noted an increase in leptospirosis cases at the 110-bed jungle hospital. The illness, caused by bacterial infection from Leptospira-contaminated soil and water, is typically mild to moderate with non-specific symptomatology, however in severe cases patients can experience organ failure or even death.
In order to gain insight on leptospirosis presentation in the region, Dr. Hii designed a study with Duke One Health team members through which local Medical Officers at three hospitals across Sarawak collected and studied clinical samples from patients presenting at their care centers with non-specific febrile illness.
Sera samples were studied with the standard local diagnostic approach, using an antibody-based latex agglutination test before sending apparent positives to a central laboratory for confirmatory microagglutination testing (MAT). As a comparison, sera samples were also tested using a commercially available Leptospira IgM ELISA assay. Paired sera and urine samples from each participant were additionally subjected to qPCR analysis to assess for molecular evidence of Leptospira infection, which can typically be detected prior to antibody development in infected patients.
A high proportion of enrolled patients were confirmed to have leptospirosis, with 55 out of 147 (37.4%) participants displaying either molecular or serologic evidence of the illness. Among these patients, common risk factors for leptospirosis such as contact with rodents or recent flooding in homes were not found to differ between patients with and without confirmed infections, however having completed primary school, and washing clothes in the river weekly were associated with a higher risk of leptospirosis.
This study identified a high prevalence of leptospirosis infections in Sarawak. Overall, the antibody-based tests were found to be less sensitive and specific than qPCR testing, though they were able to detect ten additional cases missed by qPCR. Nevertheless, this highlights a need to develop more effective screening tools that can be used early in the disease progression when medical treatments have the best chance of supporting patient recovery.
The full article will soon be available on the journal’s web site: Tropical Diseases, Travel Medicine and Vaccines.