CDC warns that delta variant is as contagious as chickenpox and may make people sicker than original Covid

CDC warns that delta variant is as contagious as chickenpox and may make people sicker than original Covid "The war has changed," CDC officials wrote in a confidential document given to lawmakers this week. Berkeley Lovelace Jr. CNBC

A confidential CDC document said delta is more transmissible than the common cold, the 1918 Spanish flu, smallpox, Ebola, MERS and SARS.

People infected with the delta variant carry up to 1,000 times more virus in their nasal passages than other strains, resulting in higher transmissibility, even among the vaccinated, according to federal health officials. The CDC noted that studies in Canada, Singapore and Scotland found higher odds of hospitalization, ICU admission, oxygen needs, pneumonia or death among people infected with the delta variant.

While the variant, which surfaced in India, continues to hit unvaccinated people the hardest, some vaccinated people could be carrying higher levels of the virus than previously understood and are potentially transmitting it to others, CDC Director Dr. Rochelle Walensky said Tuesday. She added the variant behaves “uniquely differently from past strains of the virus.”