The number of confirmed cases of COVID-19, the potentially deadly disease caused by the novel coronavirus, is climbing rapidly in the U.S. and now exceeds 100,000. The U.S. recently surpassed China (where the disease is believed to have originated) and Italy to become the nation with the greatest number of cases.

The number of people infected with the disease is growing exponentially in the U.S. Confirmed cases have doubled in roughly three days and have risen approximately tenfold in the past week. The number of confirmed cased of COVID-19 also continues to climb in nearly every country and now exceeds 590,000 worldwide.

"The pandemic is accelerating," World Health Organization Director-General Tedros Adhanom Ghebreyesus said at a recent press briefing. "It took 67 days from the first reported case to reach 100,000 cases, 11 days for second 100,000 cases, and just four days for the third 100,000 cases."

A person in medical attire holding a COVID-19 blood test vial.

COVID-19 cases are growing quickly in the U.S. and around the world. Image source: Getty Images.

The rapidly climbing number of cases in the U.S. coincides with improved access to diagnostic tests. Quest Diagnostics (NYSE:DGX) and Laboratory Corporation of America (NYSE:LH) recently began offering testing services for COVID-19. The two clinical lab giants told CNBC on Tuesday they're ramping up production and will soon be able to process more than 300,000 tests per week. But there's still a shortage of tests in many areas, as well as restrictions on who can get tested, so health officials say the actual number of COVID-19 cases is likely much higher.

Social distancing techniques are one of the best ways to reduce the transmission of COVID-19, according to the Centers for Disease Control and Prevention. In turn, numerous governors and local officials are issuing stay-at-home directives to slow the spread of the disease.

However, President Trump has so far resisted calls for a nationwide lockdown, even as health officials warn that a full-scale national containment effort is needed to slow the rate of new infections to a point where the country's healthcare system could effectively treat all patients in need of care. As a result, many states have chosen to forego issuing stay-at-home orders, which some doctors say is contributing to the rapid pace of disease transmission.

Microsoft co-founder Bill Gates, who is widely regarded as an expert on pandemics due to his foundation's role in combating infectious diseases around the world, reiterated calls for a unified national effort to combat COVID-19. "If we do it right, we'll only have to do it once for 6 to 10 weeks, but it has to be the whole country," Gates said.