The health secretary has chipped away at the idea that immunizing children against measles and other diseases is a public health good.

© Niki Chan Wylie for The New York Times

The nation’s health secretary addressed agency employees, asking them to shed any corporate influence. But he did not address the mass layoffs that have gutted oversight of tobacco and vapes, food safety and drug reviews.

© Ash Ponders for The New York Times

The health secretary has chipped away at the idea that immunizing children against measles and other diseases is a public health good.

© Niki Chan Wylie for The New York Times

The vets had no symptoms, and one worked only in states where no dairy infections had been reported.

President Trump pledged to lower costs on “Day 1” as a candidate. His administration now acknowledges it will take more time.

The facility in western Ohio was licensed to house about 280,000 young hens raised to lay eggs. The destruction came amid egg shortages linked to an avian influenza outbreak.

A new version of the virus is widespread in wild birds but had not previously been detected in cows.

I’ve seen U.S.A.I.D. operate around the world, and it’s not woke — it’s lifesaving.

Scientists were slow to recognize that Covid spreads through the air. Some are now trying to get ahead of the bird flu.

When we face some risk of a bird flu pandemic, do we want to entrust our health to a man who has fought lifesaving vaccines?

In recent months, bird flu has started raising red flags among scientists and public health officials. Apoorva Mandavilli, a New York Times reporter who covers infectious diseases, explains why we need to start taking bird flu seriously.

A pandemic is not inevitable, scientists say. But the outbreak has passed worrisome milestones in recent weeks, including cattle that may have been reinfected.

Avian influenza has led to a shortage of eggs and wholesale prices that are through the roof. Consumers can expect to feel the pain for a while.

The cases have spurred new pet food safety rules and poultry surveillance efforts.

The highly infectious H5N1 strain has caused outbreaks across the country. Now, Long Island’s last duck farm must kill its entire flock and may go out of business, its owner said.

Scientific meetings were canceled, and research data on the bird flu outbreak was delayed, amid confusion over the directive.

The deceased was over 65 and had other medical conditions, state officials said.

The administration is committing an additional $306 million toward battling the virus, and will distribute the money before President-elect Donald J. Trump takes office.

Tiny genetic alterations could help the bird flu virus enter cells in the upper respiratory tract, the C.D.C. said. But there is no sign that mutations are widespread in nature.