Chemotherapy in the control of urinary schistosomiasis in Nigeria

Area of Science:

• Tropical Medicine
• Infectious Diseases
• Pharmacology

Background:

• Schistosomiasis is a significant public health concern, particularly in endemic areas.
• Praziquantel is a primary drug for schistosomiasis treatment, but optimal dosing for cost-effectiveness requires study.
• Intestinal helminth co-infections are common and may impact treatment strategies.

Purpose of the Study:

• To determine the minimal cost-effective dose of praziquantel for treating schistosomiasis in Nigerian school children.
• To evaluate the efficacy and safety of praziquantel in a selective chemotherapy program.
• To assess the drug's impact on co-existing intestinal helminth infections.

Main Methods:

• A selective chemotherapy approach was used involving 135 school children aged 6-15 years.
• Praziquantel dosage was evaluated, focusing on the minimal effective dose.
• Treatment outcomes, including infection clearance and side effects, were monitored over 18 months.

Main Results:

• Praziquantel cleared urinary schistosomiasis in 99.1% of subjects at the dosages used.
• The lowest effective dose (20 mg/kg body weight) cleared light infections.
• Prevalence of schistosomiasis decreased from 16.0% to 0.59% post-treatment.
• Praziquantel showed no significant effect on heavy intestinal helminth loads.
• Minimal side effects were reported, and reinfection rates were low (0.59% after 18 months).

Conclusions:

• Low-dose praziquantel is a cost-effective treatment for light to moderate schistosomiasis in Nigerian school children.
• Selective chemotherapy with praziquantel significantly reduces schistosomiasis prevalence.
• The drug is well-tolerated, making it suitable for mass drug administration programs.