The World Health Organization's Strategic Advisory Group of Experts on Immunization is recommending boosters for moderately and severely immunocompromised people. The group is also recommending a third dose of China's Sinovac and Sinopharm vaccines for people 60 and older.

The WHO's Director-General had previously called for a moratorium on boosters, citing inequities in access to vaccines. High-income countries have administered 35 times more vaccine doses than low-income countries. Countries in the WHO Africa Region have only fully vaccinated 3% of their populations.

-ABC News' Christine Theodorou

All in-person runners must be fully vaccinated two weeks ahead of next month's Philadelphia Marathon, officials announced. Runners with only a negative test won't qualify.

The race is set for Nov. 21.

Although daily deaths have declined by about 17% in the last four weeks, the U.S. is still reporting an average of 1,465 new deaths each day, according to federal data. Over the last four days alone, the U.S. reported another 7,500 confirmed COVID-19 deaths.

The death average is nearly eight times higher than in mid-July when the national average had dropped to a near pandemic low of 192 daily deaths, according to federal data.

But hospitalization admissions have dropped by about 11.4% in the last week, according to federal data.

There are currently about 65,000 COVID-19 patients in U.S. hospitals, down from 104,000 patients in late August.

In the Mountain Region -- Colorado, Montana, North Dakota, South Dakota, Utah and Wyoming -- hospital admissions are steadily trending up, federal data show. In the Northeast, hospital admissions are no longer trending down.

-ABC News' Arielle Mitropoulos

The Boston Marathon returned with 18,000 runners on Monday following a two-year hiatus.

The field size was reduced by 36% this year while another 28,000 runners participated in the race virtually.

Runners were required to provide proof of vaccination or a negative COVID-19 test. Although masks were not mandated for the 26.2-mile course, face coverings were enforced on participant transportation, as well as for volunteers who interacted with participants.

According to the Boston Marathon Association, 95% of all Boston Marathon volunteers were vaccinated and 100% of Boston Marathon medical volunteers were vaccinated.

In recent weeks, cases have been creeping up in several states in the Upper Midwest and Northeast. Colorado, New Hampshire, Vermont, Montana, Michigan and Minnesota have seen their case rates jump by 20% or more in the last month, according to federal data.

Alaska currently has the country's highest infection rate, followed by Montana, Wyoming, North Dakota, Idaho and West Virginia, according to federal data. California currently has the nation's lowest infection rate.

Since the beginning of September, the U.S. has seen a drop of more than 42,000 COVID-19 patients in hospitals. Daily COVID-19-related hospital admissions are also down by 8.8% in the last week, and by more than 40% in the last month, according to federal data.

West Virginia currently has the country's highest death rate, followed by Idaho and Georgia. Texas alone is reporting thousands of deaths each week.

-ABC News' Arielle Mitropoulos