Efficacy of Hydroxychloroquine Sulphate for Treating Disease Caused by Cryptocaryon irritans Brown, 1951 in Marine Ornamental Fish
Pedro Henrique Magalhães Cardoso, Simone De Carvalho Balian, Herbert Sousa Soares, Beatriz Dos Santos Neves Kahwage, Liura Sanchez Lauri, Maurício Laterça MartinsCryptocaryon irritans is a ciliate protozoan parasite of wild and cultivated marine fish and causes the clinical signs of white spot disease. It results in significant losses for aquarists and commercial fishermen worldwide and infects various marine teleosts. This study reports on the efficacy of the administration of hydroxychloroquine sulphate as a treatment for white spot disease caused by C. irritans. Nine marine ornamental fish of different species showed behavioural changes such as flashing and had white spots on their skin and fins. Four fish with higher numbers of white spots were subjected to skin scraping to confirm the diagnosis under a microscope, through which the presence of C. irritans was confirmed. The aquarium containing these fish species was treated with 20 mg L-1 of hydroxychloroquine sulphate for fifteen days. One day after the addition of hydroxychloroquine sulphate to the tank, positive behavioural changes were observed among the fish. On the third day, none of the nine fish had signs of white spots visible, and no parasites were found on the skin scraping sample. In the study, it was concluded that hydroxychloroquine improved the clinical signs and prognosis of the disease caused by C. irritans in the fish species examined.