Why does McCarthy likely mention John Service and Gustave Duran in paragraphs
12-14?

MacCarthy most likely introduces John Service and Gustave Duran from the paragraphs 12 to 14 as he wished to prove that they both were communists and dignified men. He wanted to show that they were the assets to the country and to prove his point he offers a variety of evidences like Gustave's job at 'Communist International Brigade ' and claims put forwards by John Service. He further substantiates his stand on both of them by asserting that Communism is a hope for the United States.

the red coloration of the lungs looks alarming and adds to the overall message that the flu is threatening apex