Snail Invasions and Schistosomiasis

Schistosomiasis has been successfully eliminated in Martinique, a country whose story represents one of the most well documented cases of inadvertent schistosomiasis control resulting from successful, widespread invasion by non-competent competitor snail species. Beginning in the 1950s – prior to widespread advocacy of snail control – many countries used integrated control measures to respond to increasing schistosomiasis prevalence rates. On Martinique, S. mansoni had been prevalent in Biomphalaria glabrata snails since the 19th century [1]. The prevalence of S. mansoni was estimated at 6.4% in 1951 and 8.4% in 1961 [3]. By 1977, the prevalence of S. mansoni had reached 12% in the human population. In the years following, Martinique initiated integrated control efforts, including improved sanitation measures and sanitary education as well as detection and treatment of patients, but snail control provided the greatest prevalence reduction [1]. The History of Schistosomiasis in Martinique