A primary challenge in schistosomiasis elimination is the lack of sensitive, accurate, accessible, and affordable diagnostic tests, particularly during the pre-elimination stage of Schistosoma japonicum, the parasite causing schistosomiasis. The current microscopic approach involves three days of stool collection, which raises concerns about community fatigue, shared stool samples between household members, and the use of the same samples for multiple sample collections.
Schistosomiasis remains a significant public health concern in parts of Indonesia, notably in Central Sulawesi. Twenty-eight villages in the region still grapple with the disease, but Indonesia is working towards stopping disease transmission. WHO contributed to this mission among others by supporting annual mass drug administration (MDA) in affected villages with free medication, and in recent years Indonesia has thus managed to maintain a low infection rate. Despite an uptick in prevalence rates during the heights of the COVID-19 pandemic, the “heavy intensity infection” rate remained under 1%, satisfying WHO’s definition of the elimination of schistosomiasis as a public health problem.
WHO played a pivotal role in Indonesia's ambitious schistosomiasis elimination programme by organizing a comprehensive five-day capacity-building workshop focusing on the recombinant antigen-enzyme linked immunosorbent assay (RA-ELISA) test in Donggala, Central Sulawesi. RA-ELISA test plays a crucial role in screening efforts in pre-elimination scenarios, particularly when schistosomiasis cases are infrequently detected in endemic regions. RA-ELISA, which is more sensitive than previous diagnosis method and relies on blood samples instead of stool samples, improves screening efficacy and mitigates community fatigue associated with participating in annual stool surveys.
The training, held at the local National Institute of Health Research and Development (NIHRD) facility, brought together 29 participants from various stakeholders, ranging from health authorities and workers to local universities. The programme began with an opening ceremony graced by authoritative figures, setting the tone for the training's objectives and emphasizing the MoH's commitment to eliminating schistosomiasis in two endemic districts of Central Sulawesi: Poso and Sigi.
Lectures and hands-on practices under experts the University of Philippines Manila covered wide-ranging topics from the historical context of schistosomiasis and the parasite's life cycle to the significance of the conventional diagnostic method and microscopy as well the Kato-Katz technique. Importantly, participants were introduced to the novel RA-ELISA test with the SjTPX1 recombinant antigen, including reagent preparations and test protocols.
The training involved a field visit to Poso District in Central Sulawesi, during which participants visited endemic villages and collected blood samples from residents. A participant group also visited a snail breeding site to observe potential intermediate hosts. On the following day, participants meticulously performed the RA-ELISA test on the samples, learning about the details of entailed in this test. Concluded with an open forum to address participants’ concerns, this WHO-initiated training is expected to significantly bolster Indonesia's efforts to eliminate schistosomiasis by ensuring a more accurate and comprehensive approach to disease surveillance and control in the region.
Training participants screening serum samples from the field with RA-ELISA.
Credit: University of Philippines Manila/Dr Jose Ma. M. Angeles
“The state-of-the-art facilities at the Donggala NIHRD laboratories are truly impressive. Their advanced laboratory capabilities are an asset for the schistosomiasis elimination programme. We are confident that Indonesia's national health authorities can readily embrace and integrate the RA-ELISA testing to enhance their surveillance capacity in their ambitious pursuit of schistosomiasis elimination by 2029,” project leader Dr. Jose Ma. M. Angeles said in Palu.
The significance of the RA-ELISA training lies in its role in accelerating schistosomiasis elimination, facilitating access to advanced diagnostic methods, and fostering public health awareness and community involvement in disease control. By empowering healthcare professionals with this more sensitive diagnostic technique, Indonesia aims to enhance surveillance precision, identify affected areas more accurately, and improve the health and welfare of communities affected by schistosomiasis.
The implementation of RA-ELISA in Indonesia holds promises. The integration of the test into the national health system is expected to bolster surveillance activities, enabling targeted interventions and more accurate disease mapping. Going forward, the RA-ELISA test use will be expanded to the animals, facilitating the monitoring and control of animal-borne diseases. This expansion will help identify reservoirs of Schistosoma japonicum infection in animals, preventing transmission to humans and supporting the One Health approach to disease management. Through these comprehensive measures, Indonesia is taking steps towards achieving its goal of eliminating schistosomiasis by 2030 and safeguarding both human and animal populations from this parasitic threat.
Written by Achmad Naufal Azhari, National Professional Officer for Neglected Tropical Diseases, WHO Indonesia.