In just over a month since a new COVID variant known as BQ.1 was first named, that strain and a descendant called BQ.1.1 have already grown to make up more than 10% of new infections across the country, according to updated estimates published Friday by the Centers for Disease Control and Prevention.  "When you get variants like that, you look at what their rate of increase is as a relative proportion of the variants, and this has a pretty troublesome doubling time," Dr. Anthony Fauci, the president's chief medical adviser, said in an interview with CBS News.  It comes as federal health authorities have been bracing for a widely-expected resurgence of COVID-19 this fall and winter. BQ.1 variants have already outpaced many rival strains in European nations from England to Germany, which have already seen renewed waves begin. The CDC had previously bundled BQ.1 and BQ.1.1 with their shared parent BA.5 in the agency's weekly "Nowcast" estimates. BQ.1 was first named by scientists in early