Coronavirus updates: Barron Trump also tested positive for COVID, Melania says
Melania Trump said she and her son have now tested negative.
A pandemic of the novel coronavirus has now killed more than 1 million people worldwide.
Over 38.4 million people across the globe have been diagnosed with COVID-19, the disease caused by the new respiratory virus, according to data compiled by the Center for Systems Science and Engineering at Johns Hopkins University. The criteria for diagnosis -- through clinical means or a lab test -- has varied from country-to-country. Still, the actual numbers are believed to be much higher due to testing shortages, many unreported cases and suspicions that some national governments are hiding or downplaying the scope of their outbreaks.
Since the first cases were detected in China in December, the virus has rapidly spread to every continent except Antarctica.
The United States is the worst-affected country, with more than 7.9 million diagnosed cases and at least 216,639 deaths.
California has the most cases of any U.S. state, with more than 865,000 people diagnosed, according to Johns Hopkins data. California is followed by Texas and Florida, with over 830,000 cases and over 741,000 cases, respectively.
More than 190 vaccine candidates for COVID-19 are being tracked by the World Health Organization, at least 10 of which are in crucial phase three studies. Of those 10 potential vaccines in late-stage trials, there are currently five that will be available in the United States if approved.
Latest headlines:
Italy records record 1-day rise in cases
Italian health authorities reported 7,332 newly diagnosed COVID-19 cases on Wednesday, topping the March 21 record when there were 6,557 new cases reported.
It should be noted that on March 21, there were only 26,336 tests done -- in the last 24 hours there were 152,196 tests.
There were an additional 43 deaths reported on Wednesday, bringing the nationwide total to 36,289. Some 539 patients are in intensive care, 25 more than Tuesday.
-ABC News' Christine Theodorou and Phoebe Natanson
Trump not spreading infectious virus, Fauci, NIH says
Tests show that President Donald Trump is not "shedding" COVID-19 after he contracted it weeks ago, medical experts say.
Anthony Fauci, director of National Institute of Allergy and Infectious Diseases, and Dr. Clifford Lane, medical director of the National Institute of Health, made the conclusion after reviewing the president's recent medical data, including a PCR test, the NIH confirmed to ABC News.
The officials believe "with a high degree of confidence" that the president is "not shedding the infectious virus."
NBC, which is holding a town hall with Trump on Thursday, first reported this information in a company press release.
ABC News' Ben Gittleson and Eric Strauss contributed to this report.
UK reports nearly 20,000 new cases as new restrictions take force
The United Kingdom registered another 19,724 positive cases of COVID-19 in the past 24 hours, a rise of 2,490 from the day before.
There were also 137 deaths within 28 days of a positive test, down slightly from the previous day's tally of 143.
The cumulative totals now stand at 654,644 positive cases and 57,690 fatalities with COVID-19 on the death certificate, according to the latest data from the U.K. government.
Fresh local restrictions were due to be implemented across swathes of England on Wednesday under a new three-tier system of COVID-19 alert levels, which British Prime Minister Boris Johnson announced on Monday.
The new measures come as England saw its number of infections quadruple in the last three weeks. There are now more patients hospitalized with COVID-19 than when the country went into lockdown in late March, according to Johnson.
White House coronavirus task force briefing shows 26 states in 'red zone'
Twenty-six U.S. states are currently considered in the "red zone" for COVID-19 cases, according to the latest White House coronavirus task force weekly briefing for governors.
Last week's briefing showed 24 states in the red zone for cases, up from 22 states the week prior. The red zone indicates more than 100 new cases per 100,000 population over the past seven days.
The latest briefing, dated Oct. 11, also shows 19 states and Washington, D.C. in the "orange zone," indicating between 51 and 100 new cases per 100,000 population last week.
Five states are in the "yellow zone," indicating between 10 and 100 new cases per 100,000 population last week, according to the latest briefing. For weeks, there was only one state -- Vermont -- listed in the green zone, but it has since been moved to the yellow zone.
Some of the states exhibiting particularly concerning trends, as detailed in the briefing, are Wisconsin, Indiana, Idaho, South Dakota, North Dakota and Montana.
ABC News' Josh Margolin and Arielle Mitropoulos contributed to this report.