Trends in areas of Oncomelania hupensis snail habitats in Anhui Province from 2004 to 2023 based on the Mann-Kendall test

Abstract

To investigate the trends in areas of Oncomelania hupensis snail habitats in Anhui Province from 2004 to 2023, so as to provide insights into facilitating the progress of schistosomiasis elimination in the province. Areas of O. hupensis snail habitats in Anhui Province from 2004 to 2023 were collected, and the trends in and mutations of O. hupensis snail habitats in Anhui Province, and the trends in O. hupensis snail habitats in different types of schistosomiasis-endemic foci and in different cities of Anhui Province from 2004 to 2023 were analyzed using Mann-Kendall test. The areas of O. hupensis snail habitats reduced by 12.62% in Anhui Province in 2023 relative to in 2004. Mann-Kendall trend test showed that the areas of O. hupensis snail habitats appeared a tendency towards a decline in Anhui Province from 2004 to 2023 (Z = -3.926, P < 0.001, β = -215.66), with an annual average reduction of 215.66 hm2. Mann-Kendall mutation test showed that the areas of O. hupensis snail habitats appeared a tendency towards a decline in Anhui Province since 2015 (|Z| > U0.05, P < 0.05). The areas of O. hupensis snail habitats appeared a tendency towards a decline in marshland and lake regions (Z = -4.899, P < 0.001, β = -260.13), and a tendency towards a rise in hilly regions of Anhui Province from 2004 to 2023 (Z = 2.758, P < 0.01, β = 44.55). Among 9 cities endemic for schistosomiasis in Anhui Province, the areas of O. hupensis snail habitats appeared a tendency towards a decline in 5 cities of Ma'anshan, Tongling, Anqing, Huangshan and Chizhou (Z = -4.056 to -2.109, all P values < 0.05, β = -92.12 to -0.45). The average constituent ratios of areas of O. hupensis snail habitats were 88.19% and 11.81% in marshland and lake regions and hilly regions of Anhui Province from 2004 to 2023, respectively, and the ratio of areas of O. hupensis snail habitats in marshland and lake regions to areas of snail habitats in hilly regions reduced from 9.23∶1 in 2004 to 5.74∶1 in 2023 in Anhui Province, with the ratio appearing a tendency towards a decline (Z = -4.477, P < 0.001, β = -0.16). The areas of O. hupensis snail habitats appeared a tendency towards a decline in Anhui Province from 2004 to 2023, with a reduction in areas of O. hupensis snail habitats in marshland and lake regions and a rise in hilly regions. Targeted O. hupensis snail control interventions are required tailored to real snail status.