Mouse hepatitis virus: A betacoronavirus model to study the virucidal activity of air disinfection equipment on surface contamination.

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected millions of people worldwide. SARS-CoV-2 belongs to the Betacoronavirus genus, containing the mouse hepatitis virus (MHV), an extensively studied animal coronavirus. Since MHV and SARS-CoV-2 share the same genus, MHV could offer insights relative to SARS-CoV-2 studies. MHV-3 strain causes hepatitis and cellular injury, making MHV-3 infection one of the best models for this debilitating disease. Surrogate coronaviruses have been used for virus resistance and inactivation studies, and although real-life conditions using SARS-CoV-2 should be encouraged, their use needs to be balanced with safety and costs. MHV can be manipulated under BSL2 laboratory conditions, unlike SARS-CoV-2, making it a model for studying the virucidal effects on coronaviruses. In this study, we used the betacoronavirus MHV-3 as a model to investigate the virucidal activity of an air disinfection equipment named STR Solution®, an air sterilizer with patented technology. MHV-3 was dried on different surfaces and exposed at varying distances from the STR Solution® equipment and at different exposure times. The residual infectivity was evaluated using the endpoint method. There was not a significant reduction (mean p-value = 0.4) of the viral titer under STR Solution® exposition. STR Solution® caused a slight decrease of the infectious particles' titer (> 1 log10) only under the following conditions: polypropylene at 3 m, for 1 and 3 h (1.2 log10 reduction TCID50) and Sus domesticus skin at 0.05 m, for 1 h (1.3 log10 reduction TCID50), and at 3 m for 1 h (1.2 log10 reduction TCID50). These and other studies confirm the usefulness of this model to evaluate virucidal activity.

Natural Vaccinia Virus Infection: Diagnosis, Isolation, and Characterization.

Natural infections of Vaccinia virus (VACV)-the prototype species of the Orthopoxvirus genus, from the family Poxviridae and subfamily Chordopoxvirinae-cause an occupational emergent zoonotic disease that is primarily associated with the handling of infected dairy cattle. In humans, VACV infection is characterized by skin lesions, primarily on the hands, and accompanied by systemic symptoms such as fever, myalgia, headache, and lymphadenopathy. The diagnosis of VACV is usually performed according to the methods described for other orthopoxviruses. This unit describes the methods utilized to obtain clinical samples, the serological and molecular techniques used for diagnosis, and the isolation methods and techniques used for molecular and biological characterization of the viruses. © 2016 by John Wiley & Sons, Inc.

Intrafamilial transmission of Vaccinia virus during a bovine Vaccinia outbreak in Brazil: a new insight in viral transmission chain.

Bovine vaccinia (BV) is an emerging zoonosis caused by the Vaccinia virus (VACV), genus Orthopoxvirus (OPV), Poxviridae family. In general, human cases are related to direct contact with sick cattle but there is a lack of information about human-to-human transmission of VACV during BV outbreaks. In this study, we epidemiologically and molecularly show a case of VACV transmission between humans in São Francisco de Itabapoana County, Rio de Janeiro state. Our group collected samples from the patients, a 49-year-old patient and his son. Our results showed that patients had developed anti-OPV IgG or IgM antibodies and presented neutralizing antibodies against OPV. The VACV isolates displayed high identity (99.9%) and were grouped in the same phylogenetic tree branch. Our data indicate that human-to-human VACV transmission occurred during a BV outbreak, raising new questions about the risk factors of the VACV transmission chain.