Understanding COVID-19, , North Star Editions, Hustad Douglas,Health & Daily Living/Diseases, Illnesses & Injuries,JUVENILE NONFICTION, science behind covid; testing covid; treating covid; symptoms of covid; transmission of covid; nonfiction; COVID-19; coronavirus; virus; pandemic; hospitals; health care; infection; symptoms; airborne virus; contagion; kids books about covid; middle grade covid books,, Core Library Guide to COVID-19, United States, en-UShttps://northstareditions.comscience behind covid; testing covid; treating covid; symptoms of covid; transmission of covid; nonfiction; COVID-19; coronavirus; virus; pandemic; hospitals; health care; infection; symptoms; airborne virus; contagion; kids books about covid; middle grade covid books, [BLURB],[CITY],,books, ebooks, biblet, Book2look