Mexican billionaire Carlos Slim, considered one of the world's richest men, has tested positive for COVID-19 and is suffering mild symptoms.

This was confirmed by the 80-year-old Mexican billionaire's family and his spokesperson on Monday. Carlos Slim Domit, the tycoon's son, tweeted that his father is very well and making good progress after more than a week of minor symptoms.

The announcement that Carlos Slim was diagnosed with COVID-19 came after Mexican President Andrés Manuel López Obrador announced that he was infected with the virus, too, AFP reported.

Slim's son said his father is getting "tests, monitoring, and timely treatment" from the National Nutrition Institute, according to CBS 17 report.

"He is very well and has had a very favorable development," Slim Domit said in the report.

Slim's fortune is estimated to be at $59.9 billion, making him the world's 21st richest person. The Mexican billionaire's most valuable asset is his stake in America Movil, a Latin American mobile telecom firm.

According to a Forbes report, Carlos Slim was included in Forbes' list of billionaires in 1991 with a fortune of $1.7 billion, which mainly depend on his Grupo Carso stake.

His most notable success started with the privatization of state-owned phone company Telmex in 1990, which was led by his industrial conglomerate Grupo Carso with France Telecom and Southwestern Bell, which is now part of AT&T.

Carlos Slim was the world's richest person in 2012, with a worth amounting to $69 million. Forbes put him on the cover then.

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Mexico's COVID-19 Death Toll

Mexico's COVID-19 death toll has surpassed 150,000, according to the government's count a day after López Obrador announced that he had contracted COVID-19.

The health ministry reported over 659 deaths in its daily update, making the total number at 150,273. According to a Yahoo News report, this makes Mexico behind the United States, Brazil, and India.

Since mid-December, Mexico City has been in a state of maximum alert. More than 90 percent of hospital beds are full due to rising infections. Meanwhile, non-essential sectors and activities have been suspended in the capital.

The country began mass immunization on Dec. 24 using the vaccine developed by U.S. drugmaker Pfizer and its German partner BioNTech. However, the nation is facing a limited supply.

A senior official from the World Health Organization said Monday the high rate of positive COVID-19 tests in Mexico likely meant the country was screening too few people. Also, hospitals in Mexico have been overwhelmed by surging cases, and the country sets two daily coronavirus death records this week.

According to The Guardian report, despite the death toll continuing to rise, the country has offered the market restriction-free travel to international tourists.

Mexican health officials have also refused to implement some specific evidence-based pandemic response measures, including mass testing. Mexico has one of the lowest testing rates in the world.

Dr. Laurie Ann Ximenez-Fyvie, director of the Molecular Genetics Laboratory at Mexico's Autonomous National University, said the country's failure to create enough testing network would make complying with new U.S. travel requirements difficult.

Ximenez-Fyvie further noted that meeting the demand of passengers traveling abroad will be a problem as the country's testing capacity is not up to the needed level. 

Related story: Residents of Mexico Are At Higher Risk for COVID-19, Says Health Professionals