The inactivation of the non-enveloped enterovirus 71 (EV71) by a novel disinfectant gel formulation for topical use.

BACKGROUND: Hand-foot-mouth disease may cause severe central nervous system complications and even death, that is induced mainly by enterovirus 71 (EV71), which is a non-enveloped virus. Inactivation of the EV71 on hands could effectively inhibit the transmission. However, the inactivations of the EV71 by conventional disinfectants including the alcohols are poor, due to the high stability of the EV71. A novel pyridyl imidazolidinone compound (TJAB1099) was designed to specifically inhibit EV71 replication in vitro. It may potentially be developed as formulations applied on hands for EV71 transmission control.

METHODS: The stress stability of TJAB1099 was first evaluated after storing in high temperature (60 °C, RH 10%), high humidity (25 °C, RH90%), and the high-intensity photolysis (4500 Lx ± 500 Lx) for 15 days, respectively. A wash-free antimicrobial gel containing the TJAB1099 was developed using the copolymer carrier. The antiviral activity, the acute oral toxicity, and the local irritation of the antimicrobial gel were evaluated accordingly.

RESULTS: The results indicated that the TJAB1099 was stable during the storage in high temperature and humidity. However, a significant change (p < .0001) was detected when TJAB1099 stored in the high-intensity photolysis. The antimicrobial gel containing 1 μM TJAB1099 could inhibit EV71 significantly higher than the ethanol (75%) (p < .0001) and commercialized disinfectant products (p < .0001). The results of acute oral toxicity and the local irritation suggest that the TJAB1099 containing antimicrobial gel was not causing skin irritations and acute oral toxicity symptoms.

CONCLUSIONS: The results suggest that the antimicrobial gel containing TJAB1099 was safe and could effectively inhibit EV71 transmission in vitro.