As the United States shatters record after record on coronavirus cases and hospitalizations, more warnings emerged from officials across the country urging residents to adjust their behavior and prepare for more possible changes on the horizon.

On the West Coast, the governors of California, Oregon and Washington urged their residents on Friday to avoid all nonessential interstate travel in the days ahead, joining their counterparts across the country in pleading with residents to take precautions.

In New York City, an early hot spot now facing a possible second wave, the mayor warned on Friday that public schools could close as early as Monday as the seven-day average positivity rate jumps. Private residential gatherings must be limited to 10 people beginning at 10 p.m.

Virus surge: Schools abandon classes, states retreat School systems in Detroit, Indianapolis, Philadelphia and suburban Minneapolis are giving up on in-person classes, and some governors are reimposing restrictions on bars and restaurants or getting... AP NEWS

School systems in Detroit, Indianapolis, Philadelphia and suburban Minneapolis are giving up on in-person classes, and some governors are reimposing restrictions on bars and restaurants or getting more serious about masks, as the coast-to-coast resurgence of the coronavirus sends deaths, hospitalizations and new infections soaring.

Thinking About a Holiday Gathering? Look at This Troubling Map First

An average of 1,193,000 tests per day we

U.S. prepares for worst four months of the pandemic as it stares down the 'darkest' days yet The U.S. is heading for a “dark winter,” a “Covid hell" that will make the next few months of the coronavirus pandemic unlike anything the nation has seen yet. Will Feuer CNBC

• Epidemiologists, scientists and public health officials are warning that the United States has yet to see the most difficult days of the coronavirus outbreak.

Can a nose-full of chicken antibodies ward off coronavirus infections? A novel project aims to temporarily protect humans from COVID-19 with a nasal spray Science | AAAS

While the world waits for a widely available, safe, and effective COVID-19 vaccine, scientists are becoming ever more creative in their search for other ways to protect people from the disease. Now, a clinical trial has begun in Australia to find out whether nasal drops that contain chicken antibodies to SARS-CoV-2 can offer temporary protection.