The outbreak of coronavirus disease 2019 (COVID-19) began in Wuhan, China in December 2019 [1, 2], and the total number of confirmed COVID-19 cases has exceeded 40 million in 211 countries around the world [3, 4]. The most severe epidemic areas are mainly located in Asia and the Americas . The impact on children has so far been relatively small compared to that on adults. The novel coronavirus (severe acute respiratory syndrome coronavirus; SARS-CoV-2) spread rapidly, sweeping across China in just a few days, causing varying degrees of respiratory disease and, in severe cases, death . Accordingly, the SARS-CoV-2 outbreak poses a massive threat to public safety, and the World Health Organization (WHO) has declared a public hygiene emergency.
Since the outbreak, we have a reached a deeper understanding of SARS-CoV-2. The genome of SARS-CoV-2 has a high degree of similarity with the coronavirus carried in bats  and the spike protein of the coronavirus is the key target of antibodies . The virus can bind to target cells via angiotensin-converting enzyme Ⅱ (ACE).
Yao et al. reported the first full three-dimensional fine structure of SARS-CoV-2 , while Zhou et al. reported the full-length genome of 2019-nCoV. It has the characteristics of a high infection rate, a wide range of transmission modes, and a high mortality rate. Therefore, people must find effective treatment and prevention methods. But at present, no vaccine or drug that is highly effective against SARS-CoV-2 has been approved for production and application [10, 11].
The SARS-CoV-2 is a respiratory disease that can be spread by direct transmission, aerosol transmission, or contact transmission. SARS-CoV-2 has a typical incubation period of 3–7 days and rarely more than 14 days. After infection, patients often develop fever, cough, fatigue, and other symptoms.
The virus can be present in the oral cavity and saliva of patients, presenting a high risk of infection and cross-infection to the medical staff in stomatological hospitals . Thus, killing the virus in the mouth is extremely important  if we are to minimize the chance of iatrogenic infections, which can have serious consequences if they occur. Accordingly, the virucidal effects of oral disinfectants on SARS-CoV-2 to reduce the possibility of oral cavity transmission of SARS-CoV-2 is an active area research at present .
Traditional disinfectors can have virucidal effects , and the oral disinfectant hexadecyl pyridinium chloride has been shown to be effective for oral sterilization  as well as having activity against the hepatitis B virus  and bacteria that cause periodontitis . Hexadecyl pyridinium chloride is a widely used personal care product that has been listed by the FDA as Generally Regarded as Safe (GRAS). More importantly, it exhibits a certain action against SARS-CoV-2 that can destroy the structure of the virus surface .
Nevertheless, there is no significant research on SARS-CoV-2 disinfection using mouthwash disinfectant. Therefore, in the present study we evaluated the inhibitive effect of hexadecyl pyridinium chloride against SARS-CoV-2 in the Vero cell model. It is hoped that this study will provide invaluable information for the use of disinfectants in oral clinical treatment during the epidemic.