Federal health officials said the new data justified a campaign of booster shots. But some scientists disagreed, saying not every American needs another dose.
Author: APOORVA MANDAVILLI
Early Data Hints at a Rise in Breakthrough Infections
With the arrival of the contagious Delta variant, Covid hospitalizations and deaths among vaccinated Americans also may have increased, according to preliminary figures.
Breakthrough Infections and the Delta Variant: What to Know
Scientific understanding of the coronavirus variant is changing quickly. Here’s a recap of the most important findings.
Vaccinated People May Spread the Virus, Though Rarely, C.D.C. Reports
The agency cited an outbreak in Provincetown, Mass., in which most of the infected were immunized. An internal C.D.C. document paints an even more harrowing picture.
The Delta variant is a ‘serious threat’ as contagious as chickenpox, the C.D.C. finds.
An internal agency document paints a grim picture of the fast-spreading coronavirus variant, saying it appears to cause serious illness and health officials must “acknowledge the war has changed.”
C.D.C. Internal Report Calls Delta Variant as Contagious as Chickenpox
Infections in vaccinated Americans are rare, compared with those in unvaccinated people, the document said. But when they occur, vaccinated people may spread the virus just as easily.
How Often Do the Vaccinated Spread Covid-19?
The C.D.C.’s new masking advice was based in part on data showing that the virus can thrive in the airways of vaccinated people. The findings are expected on Friday.
PEPFAR Is Still Without a Leader. H.I.V. Activists Want to Know Why.
“Can we not think and act on two pandemics at a time?” asked one epidemiologist.
J.&J. Vaccine May Be Less Effective Against Delta, Study Suggests
Many who received the shot may need to consider boosters, the authors said. But federal health officials do not recommend second doses.