LONDON, Nov. 20 (Xinhua) -- Scientists have said the United States could see significant increases in COVID-19 cases this winter, particularly in the nation's colder regions, The Guardian reported Thursday.

The paper said a steep rise in COVID-19 cases in Europe should serve as a warning to the United States because only 58.6 percent of the U.S. population is vaccinated, lower than vaccination rates in some European nations now struggling with a spike in COVID-19 cases, such as in Germany and France.

Furthermore, it also said vaccine distribution is highly uneven across the United States, which could worsen the problem.

Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine and co-director of the Texas Children's hospital's center for vaccine development, predicted "a pretty bad winter wave" and believed "it looks like it's starting to happen."

"There's just too many unvaccinated and too many partially vaccinated (people)" to stop the "aggressive" Delta variant, the paper quoted Hotez as saying.