FACTBOX-Latest on the worldwide spread of the coronavirus

* The U.S. FDA released guidance on its conditions for approving a vaccine for the coronavirus, saying a vaccine has to prevent or decrease disease severity in at least 50% of people who are vaccinated. ECONOMIC FALLOUT * Global M&A activity tumbled to its lowest level in more than a decade in the second quarter, according to data provider Refinitiv. * China's factory activity grew at a faster clip in June after the government lifted lockdown measures and ramped up support steps, but the health crisis continues to pressure exports and jobs, a private business survey showed.

New U.S. COVID-19 cases rose by more than 47,000 on Tuesday according to a Reuters tally, the biggest one-day spike since the start of the pandemic, as the government's top infectious disease expert warned that number could soon double.

DEATHS AND INFECTIONS

AMERICAS

* Three asylum seekers have tested positive for coronavirus in sprawling encampment steps from the U.S. border in Matamoros, Mexico, marking the first cases in a settlement that advocates have long viewed as vulnerable amid the pandemic.

* Canada is extending a global travel ban and mandatory quarantine measures that require most travelers to Canada, including citizens returning home, to self-isolate for 14 days upon the arrival.

* U.S. senators called for a government analysis of foreign influence in the U.S. pharmaceutical supply chain.

ASIA-PACIFIC

* South Korea has started distributing stocks of the COVID-19 treatment remdesivir which have been donated by Gilead Sciences Inc and plans to begin talks to purchase more supplies in August, its disease control agency said.

* Authorities will lockdown around 300,000 people in suburbs north of Melbourne for a month from late on Wednesday.

EUROPE

* The European Union has excluded the United States from its initial "safe list" of countries from which the bloc will allow non-essential travel from Wednesday.

* China has halted almost all imports of pork from the Netherlands, apparently motivated by COVID-19 outbreaks at some of the largest Dutch slaughterhouses.

MIDDLE EAST AND AFRICA

* The United Nations raised $7.7 billion in humanitarian aid for Syria.

* Nigeria will allow travel between its states outside curfew hours from July 1.

MEDICAL DEVELOPMENTS

* An experimental coronavirus vaccine developed by Inovio Pharmaceuticals Inc showed promise and was found to be safe in an early-stage human trial, the company said.

* The U.S. FDA released guidance on its conditions for approving a vaccine for the coronavirus, saying a vaccine has to prevent or decrease disease severity in at least 50% of people who are vaccinated.

ECONOMIC FALLOUT

* Global M&A activity tumbled to its lowest level in more than a decade in the second quarter, according to data provider Refinitiv.

* China's factory activity grew at a faster clip in June after the government lifted lockdown measures and ramped up support steps, but the health crisis continues to pressure exports and jobs, a private business survey showed.

* Japanese manufacturers' confidence sank in the second quarter to levels not seen since the 2009 global financial crisis.

* Up to $140 billion in loans for small business could be refocused to support restaurants, hotels and other industries hit hardest by the pandemic, U.S. Treasury Secretary Steven Mnuchin said.