Diagnosis and treatment of schistosomiasis in children in the era of intensified control

Abstract

In the current era of intensified and integrated control against schistosomiasis and other neglected tropical diseases, there is a need to carefully rethink and take into consideration disease-specific issues pertaining to the diagnosis, prevention, control and local elimination. Here, we present a comprehensive overview about schistosomiasis including recent trends in the number of people treated with praziquantel and the latest developments in diagnosis and control. Particular emphasis is placed on children. Identified research needs are offered for consideration; namely, expanding our knowledge about schistosomiasis in preschool-aged children, assessing and quantifying the impact of schistosomiasis on infectious and noncommunicable diseases, developing new antischistosomal drugs and child-friendly formulations, designing and implementing setting-specific control packages and developing highly sensitive, but simple diagnostic tools that are able to detect very light infections in young children and in people living in areas targeted for schistosomiasis elimination.

Keywords::

• behavior change
• co-infection
• control
• diagnosis
• elimination
• praziquantel
• sanitation
• schistosomiasis
• snail control
• treatment

Financial & competing interests disclosure

This work is part of the NIDIAG network (collaborative project; www. NIDIAG.org) supported by the European Commission under the Health Cooperation Work Programme of the 7th Framework Programme (grant agreement no. 260260). S Knopp acknowledges additional financial support from the Schistosomiasis Consortium for Operational Research and Evaluation (sub-award no. RR374-053/4893196). The research of K. Ingram and J Keiser is financially supported by the Swiss National Science Foundation (PPOOA-114941 and PPOOP3_135170) and the Scientific & Technological Cooperation Program Switzerland-Russia. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• • The impact of acute and chronic schistosomiasis on children’s physical fitness, cognition and nutritional disorders remains to be investigated in well-designed, confounder-adjusted trials to contribute to accurate burden estimates.

• • The impact of schistosomiasis on the susceptibility, development and transmission of co-infections and on their treatment and prevention remains to be studied.

• • There is a pressing need to develop new drugs and vaccines that are efficacious against all stages of the Schistosoma parasites, particularly in view of up-scaling the current administration of praziquantel, which holds the risk of developing drug-resistant parasites.

• • Highly sensitive diagnostic tools to detect light-intensity infections are needed for an accurate assessment of control interventions, and for monitoring and surveillance once interruption of transmission has been achieved and for verification of local elimination.

• • Integration of preventive chemotherapy with other control measures such as snail control, access to clean water, improved sanitation and health education is necessary to escalate from morbidity control to transmission interruption and ultimately elimination.

• • Control interventions must be adapted to the social–ecological settings and accepted and supported by the local government and communities to become successful.

• • Effective partnerships between scientists, control managers and public health experts, the private sector and intersectoral collaboration are necessary for long-term sustainable control/elimination of schistosomiasis.