Prevention and control of loiasis
To date only little is in our hands to effectively prevent Loa loa transmission. One first important measure is health education about the mode of transmission of loiasis, which is unknown to a majority of residents of high-transmission regions. Hence the avoidance of fly-bites during the daytime is of high importance. This can be achieved by wearing long-sleeved clothes of bright colours, or protective garments including mosquito-net geared hats when being outside and by screening of houses to avoid flies entering the dwellings. Despite an absence of systematic evaluation, it is assumed that repellents (e.g. DEET) are reducing the number of fly bites and may therefore be used as additional preventive tool.
Long-term travellers to endemic regions with exceptionally high risk for infection (e.g. forest workers, researchers, missionaries, military personnel) may consider weekly intake of DEC as prophylactic regimen.
To date no tools are readily available to control the transmission of loiasis on a population level. Fly control is notoriously difficult due to the breeding of Chrysops in the muddy vegetation of the rainforest and an absence of effective traps. Mass drug administration programs are hampered by the lack of easy to use and safe drugs. Therefore, no control program against loiasis is in place in any region of the endemic world. The development of tools that may be used in integrated control programs is therefore one of the main research priorities.
References:
Ramharter M, Butler J, Mombo-Ngoma G, Nordmann T, Davi SD, Zoleko Manego R. Lancet Infect Dis. 2024 Mar;24(3):e165-e178. doi: 10.1016/S1473-3099(23)00438-3.
