Tolerance to diethylcarbamazine-medicated salt in individuals infected with Onchocerca volvulus

Area of Science:

• Tropical Medicine
• Parasitology
• Public Health

Background:

• Filariasis, including Onchocerca volvulus and Wuchereria bancrofti infections, poses a significant global health burden.
• Diethylcarbamazine (DEC) is a key drug for lymphatic filariasis control, but its use in areas with co-infections needs careful evaluation.
• Assessing the safety and efficacy of DEC-medicated salt in mixed infection scenarios is crucial for public health strategies.

Purpose of the Study:

• To evaluate the tolerance and adverse reactions to DEC-medicated salt in individuals infected with Onchocerca volvulus, Wuchereria bancrofti, or both.
• To determine the impact of DEC-medicated salt on microfilarial loads of O. volvulus and W. bancrofti.
• To explore the feasibility of using DEC-medicated salt for bancroftian filariasis control in regions with incidental O. volvulus infections.

Main Methods:

• A double-blind, placebo-controlled hospital-based trial was conducted in Tanzania in 1996.
• Four groups of 10 adult males each were enrolled, with varying microfilarial infections (O. volvulus only, W. bancrofti only, or mixed).
• Participants received either DEC-medicated salt (0.33% w/w) or normal salt for 10 days, with adverse reactions and microfilarial geometric mean intensities (GMIs) monitored.

Main Results:

• Mild-to-moderate itching and rash were the most common adverse reactions in groups receiving DEC-medicated salt, resolving within 20 days post-treatment.
• DEC-medicated salt did not significantly affect Onchocerca volvulus microfilarial geometric mean intensities (GMIs).
• A significant reduction in Wuchereria bancrofti microfilarial GMIs was observed in individuals treated with DEC-medicated salt.

Conclusions:

• DEC-medicated salt is generally well-tolerated, with manageable side effects, in individuals with O. volvulus infections.
• DEC-medicated salt demonstrates efficacy in reducing W. bancrofti microfilarial loads.
• The findings support the potential use of DEC-medicated salt for controlling bancroftian filariasis, even in areas where O. volvulus infections may co-exist.