Temperature dependence of Opisthorchis felineus infection in the first intermediate host snail, Bithynia troschelii

• Published in: Acta tropica 2024-05, Vol.253, p.107166-107166, Article 107166
• Main Authors: Ponomareva, Natalia M., Orlova, Tamara V., Vlasenko, Pavel G., Serbina, Elena A., Yurlova, Natalia I.
• Format: Article
• Language: English
• Subjects: Animals; Bithyniidae; Climate change; Gastropoda; Hibernation; Humans; Opisthorchiasis - epidemiology; Opisthorchiasis - veterinary; Opisthorchis; Opisthorchis felineus; Snails; Temperature; Water; Western Siberia
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2024.107166

•Infection rate of B. troschelii by trematoda O. felineus increased with increasing of water temperature. A possible increase in opisthorchiid infection of snails under global warming must be taken into account when planning epidemiological measures.•The autumn-winter diapause in snails life causes a “delay” in the development of intramolusken stages of opisthorchiid. Cercariae of O. felineus from B. troschelii in Western Siberia emergence only the next year after snail's infection.•Сomplete hibernation of B. troschelii In Western Siberia is observed at 10 °C.•The prevalence of O. felineus infection in B. troschelii under experimental conditions was significantly higher (30–45 %), compare with 0.19 % in natural infection survey. Opisthorchiasis is one of the most serious trematodiases in Russia, where the world's largest focus is located in the Ob basin. Temperature is an important factor affecting the metabolism of cold-blooded animals. It determines the development of the causative agent of opisthorchiasis, Opisthorchis felineus, and the success of infection of an intermediate host, the snail Bithynia troschelii. In the present study, the effect of water temperature on the development of the liver fluke O. felineus in the host snail was assessed, as was the temperature threshold at which B. troschelii hibernation initiates. Adult uninfected B. troschelii individuals collected from natural bodies of water were infected with O. felineus and maintained at different temperatures of water (18–30 °C, intervals of 3 °C) in the laboratory. Each snail was fed with embryonated uterine eggs of O. felineus at 24 °C. O. felineus infection in snails was detected using polymerase chain reaction (PCR) using specific primers. The prevalence of O. felineus infection in B. troschelii depends on the water temperature in which the snails are maintained. The highest infection rate of 45.2 % ± 12.1 % was observed at 27 °C (p ≥ 0.1). The longest lifespan of infected and uninfected B. troschelii was recorded at water temperatures of 24 and 27 °C. The snails were more successfully infected at the beginning of the warm season. Among the infected individuals, the majority (up to 85 %) were large snails. Cercarial shedding was not detected in experimentally infected snails. Apparently, this is due to the natural physiological state of Bithynia snails during the autumn–winter diapause, when opisthorchiids development in snails stops. At 10 °C, complete hibernation of all B. troscheli