Worldwide coronavirus cases top 30 million

The total number of global cases has doubled since July 22.

A pandemic of the novel coronavirus has now killed more than 942,000 people worldwide.

Over 30 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.

The United States is the worst-affected country, with more than 6.6 million diagnosed cases and at least 197,397 deaths.

California has the most cases of any U.S. state, with more than 773,000 people diagnosed, according to Johns Hopkins data. California is followed by Texas and Florida, with over 697,000 cases and over 674,000 cases, respectively.

Nearly 170 vaccine candidates for COVID-19 are being tracked by the World Health Organization, at least six of which are in crucial phase three trials.

Global COVID-19 cases top 30 million

The number of confirmed COVID-19 cases has surpassed 30 million worldwide.

There are 30,019,763 cases globally as of Thursday evening, according to a tally by Johns Hopkins University.

The total number of cases has doubled in the two months since July 22, when the globe crossed the 15 million mark, based on the university's tally.

It took about six months to reach 15 million cases from the time the pandemic began near the start of the year.

The United States has the highest number of COVID-19 cases, followed by India, which on Thursday recorded the highest one-day jump in new cases anywhere in the world since the pandemic began, with 97,894.

Utah reports highest single-day case count

Utah on Thursday reported its highest single-day case count since the beginning of the pandemic, said Gov. Gary Herbert.

"This week, the state has seen a troubling spike in COVID cases after a promising August," Herbert tweeted, calling this "a wake up call."

"Fortunately, we have not yet seen a spike in hospitalizations or deaths related to this current spike -- but as those are lagging indicators -- we may see increased hospitalizations and deaths, much like we did from the surge in July," he said.

Herbert said he called an emergency meeting of Utah's Unified Command and is meeting with "local stakeholders, epidemiologists and medical experts to develop a targeted plan to contain these outbreaks." The governor also urged local leaders to make sure their policies are in the best shape possible.

ABC News' Matt Fuhrman contributed to this report.

Texas businesses to soon up capacity to 75%

In Texas -- which has the second highest number of coronavirus cases in the U.S. -- most of the state will allow businesses to operate at 75% capacity, up from 50%, beginning on Monday.

Rules for reopening are based on Texas' 22 "hospital regions." Nineteen of the 22 regions have less than 15% of hospital patients diagnosed with COVID-19, so those regions can reopen restaurants, retail, offices, museums, libraries and manufacturing at 75% capacity.

The only parts of the state where businesses cannot reopen at 75% capacity are the Rio Grande Valley, the Laredo area and the Victoria area. To qualify for a 75% capacity reopening, those locations must get their hospitals to under 15% COVID-19 patients for at least one week.

Bars across Texas are required to stay closed because they are "nationally recognized as COVID spreading locations," said Gov. Greg Abbott.

California has the most COVID-19 cases of any state, with more than 772,000 people diagnosed, while Texas ranks No. 2 with over 696,000 cases, according to Johns Hopkins data.

ABC News' Matt Fuhrman contributed to this report.

Abu Dhabi using smartwatch tech to enforce self-quarantines

All travelers arriving at Abu Dhabi International Airport are required to undergo thermal screening, take a COVID-19 test and self-quarantine for two weeks.

After clearing immigration, those who arrive will also be required to wear a free, medically approved wristband during their self-quarantine, Etihad Airlines confirmed in a statement to ABC News.

Only United Arab Emirates (UAE) nationals are allowed to fly into Abu Dhabi International Airport. UAE nationals arriving at the airport would be exempt from wearing wristbands if they hold diplomatic passports, are under the age of 18, over the age of 60, or have a chronic disease.

According to the UAE government portal, authorities in Abu Dhabi have been using the technology to track and monitor people diagnosed with COVID-19 to make sure they are self-quarantining.

The UAE has over 81,000 COVID-19 cases and at least 402 fatalities, according to the state-run WAM news agency.

ABC News' Christine Theodorou, Clark Bentson and Ibtissem Guenfoud contributed to this report.