Therapeutic efficacy of n-Docosanol against velogenic Newcastle disease virus infection in domestic chickens

INTRODUCTION: The control of Newcastle disease virus (NDV) infection depends solely on vaccination which in most cases is not sufficient to restrain the consequences of such a highly evolving viral disease. Finding out substances for preparing an efficient anti-ND drug would be of high value. n-Docosanol is a saturated fatty alcohol with an inhibitory effect against many enveloped viruses. In this study, we evaluated the therapeutic effect of n-docosanol on NDV infection and shedding in chickens. METHODS: Chickens infected with a highly virulent NDV were treated with low to high concentrations of n-docosanol (20, 40, and 60 mg/kg body weight) for 4-successive days, once they showed the disease symptoms. Survival and curative rates, virus load, histopathological scoring, and virus shedding were defined. RESULTS: Symptoms development was found to discontinue 24–72 hours post-treatment. Survival rate in the NDV-infected chickens raised 37.4–53.2% after the treatment. n-Docosanol treatment was also found to significantly reduce virus load in the digestive (26.2–33.9%), respiratory (38.3–63%), nervous (26.7–51.1%), and lymphatic (16.4–29.1%) tissues. Histopathological scoring of NDV lesions revealed prominent rescue effects on the histology of different tissues. Importantly, n-docosanol treatment significantly reduced virus shedding in oropharyngeal discharge and feces thereby allowing the restriction of NDV spread. CONCLUSION: Our findings suggest n-docosanol as a promising remedy in the control strategy of Newcastle disease in the poultry industry.