Survival of first-stage larvae of the cat lungworm Troglostrongylus brevior (Strongylida: Crenosomatidae) under different conditions

Troglostrongylus brevior has recently been recognised as a neglected causative agent of broncho-pulmonary infestation in domestic cats. Nonetheless, information on the biology and ecology of this nematode is still scarce. In this study, the survival of T. brevior first-stage larvae (L1) was evaluated in water and in faecal samples at different controlled temperatures in the laboratory (i.e., 4 and 26°C) or in the outdoor environment (mean temperature 14±3.1°C). Vitality of larvae was microscopically assessed every 7days, until their death. Larval survival ranged from 7days in both water and faeces at 26°C up to 142days at 4°C, respectively. Larvae maintained in the environment (14°C) survived from 35 up to 63days in faeces and water, respectively. Data herein presented clearly indicate that the survival of T. brevior L1s is negatively correlated with temperature (P<0.001). According to the results of this study, the infection in mollusc intermediate hosts in the Mediterranean area may easily occur during winter/spring, while during hot and dry seasons a reduction of transmission should be expected.