Erythromycin Estolate Is a Potent Inhibitor Against HCoV-OC43 by Directly Inactivating the Virus Particle.

In addition to antibacterial effects, macrolide antibiotics exhibit other extensive pharmacological effects, such as anti-inflammatory and antiviral activities. Erythromycin estolate, one of the macrolide antibiotics, was previously investigated to effectively inhibit infections of various flaviviruses including Zika virus, dengue virus, and yellow fever virus, but its antiviral effect against human coronavirus remains unknown. Thus, the current study was designed to evaluate the antiviral efficacy of erythromycin estolate against human coronavirus strain OC43 (HCoV-OC43) and to illustrate the underlying mechanisms. Erythromycin estolate effectively inhibited HCoV-OC43 infection in different cell types and significantly reduced virus titers at safe concentration without cell cytotoxicity. Furthermore, erythromycin estolate was identified to inhibit HCoV-OC43 infection at the early stage and to irreversibly inactivate virus by disrupting the integrity of the viral membrane whose lipid component might be the target of action. Together, it was demonstrated that erythromycin estolate could be a potential therapeutic drug for HCoV-OC43 infection.

Montelukast Inhibits HCoV-OC43 Infection as a Viral Inactivator.

Coronaviruses (CoVs) consist of a large group of RNA viruses causing various diseases in humans and in lots of animals. Human coronavirus (HCoV) OC43, the prototype of beta-coronavirus discovered in the 1960s, has been circulating in humans for long time, and infection with other emerging strains of beta-coronavirus (SARS-CoV, SARS-CoV-2, and MERS-CoV) can lead to severe illness and death. In this study, we found that montelukast, a leukotriene receptor antagonist, potently inhibited the infection of HCoV-OC43 in distinct cells in a dose- and time- dependent manner. Additionally, the results showed that montelukast induced release of HCoV-OC43 genomic RNA by disrupting the integrity of the viral lipid membrane, and irreversibly inhibited viral infection. Considering the similarity among HCoV-OC43, MERS-CoV, and SARS-CoV-2, it suggests that montelukast may be a potential candidate for the treatment of human beta-coronavirus infection.

Coronavirus disease 2019(COVID-19)

On December 8,2019, the first case of unexplained pneumonia was found in Wuhan, Hubei Province, China. Genetic analysis and virus isolation confirmed that the disease was caused by a new coronavirus. From mid-January 2020, the epidemic rate of the disease in China has accelerated and some cases have been transmitted abroad through tourism, and by the end of mid-April, more than 200 countries and regions have reported cases of the disease imported and caused locally. As of 11:30 April 24, the number of new coronavirus infections worldwide exceeded 2.64 million, with more than 100,000 associated deaths. A brief review of the pathogen, epidemiological characteristics, clinical treatment and prevention and treatment of the disease (COVID-19) is presented.