Journal Article

Common Laboratory Mice Are Susceptible to Infection with the SARS-CoV-2 Beta Variant

Freitag, Tobias L., Sironen, Tarja, Strandin, Tomas, Kant, Ravi, Saksela, Kalle, Alitalo, Kari, Vapalahti, Olli, Kareinen, Lauri, Kipar, Anja, Meri, Seppo, Smura, Teemu, Jha, Sawan Kumar

2021

Overview

Small animal models are of crucial importance for assessing COVID-19 countermeasures. Common laboratory mice would be well-suited for this purpose but are not susceptible to infection with wild-type SARS-CoV-2. However, the development of mouse-adapted virus strains has revealed key mutations in the SARS-CoV-2 spike protein that increase infectivity, and interestingly, many of these mutations are also present in naturally occurring SARS-CoV-2 variants of concern. This suggests that these variants might have the ability to infect common laboratory mice. Herein we show that the SARS-CoV-2 beta variant attains infectibility to BALB/c mice and causes pulmonary changes within 2–3 days post infection, consistent with results seen in other murine models of COVID-19, at a reasonable virus dose (2 × 105 PFU). The findings suggest that common laboratory mice can serve as the animal model of choice for testing the effectiveness of antiviral drugs and vaccines against SARS-CoV-2.

• Publisher: MDPI AG,MDPI
• Subject: Animal models / Animals / Antibodies / Antiviral agents / Antiviral drugs / Brain - virology / COVID-19 / COVID-19 - pathology / COVID-19 - virology / COVID-19 infection / Disease Models, Animal / disease susceptibility / Female / Infections / Infectivity / Inflammation / Laboratories / Laboratory animals / laboratory mice / Lung - pathology / Lung - virology / Lungs / Male / Mice / Mice, Inbred BALB C / Mutation / Nose - virology / pathogenicity / Pulmonary Alveoli - pathology / RNA polymerase / SARS-CoV-2 - isolation & purification / SARS-CoV-2 beta variants / SARS-CoV-2 variants / SARS-CoV2 / Severe acute respiratory syndrome coronavirus 2 / Spike protein / Viruses