Evaluation of the Embryonic Pathological Lesions and Efficacy of Amantadine against H9N2 Influenza Virus Using Chicken Embryo Model

Various antiviral drugs such as amantadine are used to treat influenza. This drug is categorized in group C and few researches have been conducted about its toxic effects on human fetus. In the current study, the pathologic effects of the drug as well as drug efficacy in reducing influenza virus titer in the developing chicken embryo were assessed.
The experiment was done on 48 fertilized eggs. Amantadine and allantoic fluid containing 105 EID50/ml of H9N2 virus were inoculated into the egg albumen, then, the pathologic effects of the drug on embryos were evaluated using macroscopic and histopathologic examinations. Drug efficacy in reducing influenza virus titer, was also assessed using the hemagglutination test.
The study showed that amantadine has adverse effect on the survival, growth, weight and internal organs during embryonic development. Histopathological examinations of the internal organs showed that pathological effects of the drug occurred in the organs, including lungs, heart, liver, kidney and brain. Furthermore, it was found that amantadine can to reduce the replication of H9N2 virus and increases the viability of the embryo.
As regards to the endemic condition of the H9N2 virus in Iran and the possibility of virus transmission to human, the utilization of amantadine is inevitable, however, the hazard of the drug for human embryo must be taken seriously.