A comprehensive timeline of the new coronavirus pandemic, from China's first COVID-19 case to the present

December 31, 2019: Chinese Health officials informed the World Health Organization about a cluster of 41 patients with a mysterious pneumonia. Most were connected to the Huanan Seafood Wholesale Market, a wet market in the city of Wuhan.

Though the first 41 cases were reported December 31, scientists determined that the virus could have started spreading from person to person as early as late November.

Case studies of how the virus has spread showed that the large gathering of people at the live animal market may have "boosted" the transmission of the virus among more people, researchers said.

Researchers think the new coronavirus originated in bats, then jumped to an intermediary species — most likely pangolins, pigs, or civets — that passed it to people. It can be spread among humans via respiratory droplets within six feet. The viruses can also survive for days on many surfaces.

The virus' pneumonia-like symptoms include fever and difficulty breathing.

January 1, 2020: Chinese authorities closed Huanan Seafood Wholesale Market.

Wuhan authorities banned the trade of live animals at all wet markets soon after the first cases. China also announced a temporary national ban on the buying, selling, and transportation of wild animals in markets, restaurants, and online marketplaces across the country — a ban later made permanent.

Farms that breed and transport wildlife to wet markets were also quarantined and shut down.

January 7: Chinese authorities identified the virus that caused the pneumonia-like illness as a new type of coronavirus (called novel coronavirus or nCoV).

Viruses in the coronavirus family can cause the common cold, pneumonia, and SARS.

January 11: China recorded its first death linked to the novel coronavirus.

January 13: The first coronavirus case outside of China was reported in Thailand.

A 61-year-old female tourist in Thailand was diagnosed on January 13. She'd recently spent time in Wuhan, China.

Airports in Hong Kong, Singapore, Thailand, and South Korea also began to closely screen passengers for fever.

January 20: The first US case is reported: a 35-year-old man in Snohomish County, Washington.

The man was evacuated from Wuhan, China, and landed back at the Seattle–Tacoma International Airport on January 15. Though he initially showed no symptoms, he reported to an urgent care clinic with symptoms of pneumonia on January 19. He was diagnosed with the virus a day later.

January 23: Chinese authorities placed the 11-million-person city of Wuhan under quarantine — and the rest of the Hubei province days later.

Though Wuhan has a population of 11 million residents, population estimates for the surrounding province placed the full lockdown at 60 million residents. This made China's action the largest quarantine in history.

January 30: WHO declared a "public-health emergency of international concern."

The WHO's determination of "global public-health emergency" has been around since 2005 and been used only five times before.

Those five include the ebola outbreak that started in 2013 in West Africa; another one that's been ongoing in the Democratic Republic of Congo since 2018; the 2016 Zika epidemic; polio emerging in war zones in 2014; and the swine-flu pandemic in 2009.

January 31: President Trump banned foreign nationals from entering the US if they had been in China within two weeks prior.

February 2: The first COVID-19-related death outside of China was recorded in the Philippines.

February 7: Chinese doctor and novel coronavirus whistleblower Li Wenliang died. At the onset of the outbreak, Wuhan-based Li warned some of his contacts from medical school about a new virus but was reprimanded by the authorities and forced to sign a letter acknowledging that he made "false comments."

Wuhan-based Li died a month after he sent out the warning message to other doctors, describing a cluster of patients with worrisome pneumonia-like symptoms at the hospital he worked at. Wuhan police had forced him sign a letter saying he was "making false comments."

Li caught the coronavirus himself after treating people who had it. Wuhan Central Hospital said at about 4 a.m. local time on February 6 that he died after "efforts to save him were ineffective."

Li died February 7, leaving behind a son and pregnant wife.

After Li's death, Chinese social media was filled with outpourings of grief and anger. Many posts featured a hashtag saying "We want freedom of speech."

February 8: A US citizen died in Wuhan from COVID-19 — the first from that country.

The US citizen was 60 years old, according to the United States Embassy in Beijing, but little else is immediately known about the American.

February 9: The death toll in China surpassed that of the 2002-2003 severe acute respiratory syndrome (SARS) epidemic, which killed about 774 people globally.

Both SARS and the new coronavirus come from the same family of viruses, and they share 80% of their genetic codes.

SARS emerged in Guangdong and infected 8,098 people globally over the course of eight months from 2002-2003, killing 774. Just a month after the first confirmed case of the novel coronavirus, the total global case count surpassed that of SARS. On February 9, the death toll from COVID-19 in China alone exceeded the total number of people killed worldwide by SARS.

The new coronavirus killed nearly three times as many people in eight weeks than SARS did in eight months.

February 11: WHO announced that the disease caused by the new coronavirus would be called "COVID-19."

"We had to find a name that did not refer to a geographical location, an animal, an individual, or group of people," WHO director-general, Tedros Adhanom Ghebreyesus, said in a press briefing.

WHO also wanted a name that was "pronounceable and related to the disease," he added.

February 12: Coronavirus cases started to spike in South Korea.

As China's number of new cases began to stabilize, South Korea's began to soar.

The Korean CDC believed that a 61-year-old female member of the controversial Shincheonji Church of Jesus, known as "Patient 31," triggered a "superspreader" event at the church's Daegu branch. She refused to be tested in hospital despite presenting symptoms, and coming into close contact with more than 1,000 churchgoers at several tightly packed services.

On February 23, South Korean president Moon Jae-in warned that the country faced "a grave turning point" in its efforts to contain the outbreak.

South Korea implemented widespread testing as a response measure. The country soon began conducting as many as 10,000 tests per day and built drive-through testing clinics that can detect coronavirus cases in just 10 minutes. Officials said the clinics reduced testing time by a third.

South Korea has tested nearly 250,000 people for the new coronavirus and confirmed more than 8,000 cases.

February 14: A Chinese tourist who tested positive for the virus died in France, becoming Europe's first death tied to the outbreak.

February 19: An outbreak of the novel coronavirus began in Iran.

With about 18,400 confirmed coronavirus cases, Iran is currently the third most-affected country in the world outside mainland China and Italy.

All of the country's schools and universities closed down February 23, along with many movie theaters and cultural centers.

Neighboring countries like Turkey and Pakistan also closed their borders with Iran. Iraq has also imposed an entry ban on any incoming Iranians.

The country released 54,000 prisoners to prevent outbreaks in its prisons.

According to Reuters, 23 members of Iran's parliament — 8% — developed the coronavirus, as well. One member, Fatemeh Rahbar, a conservative lawmaker from Tehran, died.

About 1,300 people have died.

The Iranian government has been accused of covering up the scale of the coronavirus and censoring the media's reporting on the outbreak. It also threatened the death penalty to those who hoard necessary materials or equipment.

February 21: The number of COVID-19 cases spiked in Italy, signaling that an outbreak in the country was beginning.

The country's coronavirus caseload has skyrocketed — more than 41,000 people have been infected and more than 3,400 have died. It has become the most-affected nation by the coronavirus aside from China.

February 29: The US confirmed its first death from COVID-19 on American soil.

The US's first publicly confirmed death related to the coronavirus was a man in his 50s who had chronic underlying health issues. He died at EvergreenHealth, a hospital in King County, Washington.

The US has reported more than 13,000 coronavirus cases across all 50 states and Washington, DC. COVID-19 has also spread to Guam, Puerto Rico, the US Virgin Islands, and other territories.

More than 175 people in the US have died from the coronavirus, with Washington state leading the death toll. Due to its population density and cosmopolitan makeup, though, New York is soon expected to lead in cases and deaths.

February 29 - March 19: Nearly all US states declared a state of emergency.

Nearly all US states have declared an emergency.

The strategic announcements can help states activate emergency response plans and spend more money on preparedness actions. Such declarations also authorize leaders to use funds to deploy additional personnel, buy equipment, and prepare stockpiles.

March 9: Italy placed all 60 million of its residents on lockdown.

Italy is the hardest-hit nation by the coronavirus outside of China.

The country initially saw two regions near Milan and Venice in the north become hotspots for cases, and locked down almost a dozen town in them on February 23, affecting an estimated 50,000 people.

The country's leadership shut down schools, museums, and public venues, and discouraged large gatherings.

On March 9, the government expanded the coronavirus restriction zone to encompass the entire nation. All stores closed, save for grocery markets and pharmacies.

March 11: WHO declared the outbreak a pandemic.

The WHO made the designation is based on the geographic spread of the disease, the severity of illnesses it causes, and its effects on society.

"Pandemic is not a word to use lightly or carelessly," WHO's director-general, Tedros Adhanom Ghebreyesus, told reporters at a press briefing announcing the determination in Geneva on March 11.

March 11: President Trump banned all travel from 26 European countries.

President Donald Trump announced a ban on travel from many European countries and the US in response to the coronavirus outbreak.

The ban came into effect on March 13 night for 26 European countries. The UK and Ireland were later added. However, the ban does not stop US citizens and some other groups from entering the country from Europe.

The ban has caused crowds and long wait times at airports across the country.

March 13: A US national emergency is declared over the novel coronavirus outbreak.

The declaration, made by President Trump, triggered the Stafford Act and allowed for more federal aid to states and municipalities. Trump said that his decision would open up access to $50 billion in aid money for US states and territories.

Meanwhile, multiples outlets reported that Congress was working on a roughly $1 trillion stimulus package to boost the economy amid the pandemic.

March 17: Italy reported 475 COVID-19 deaths, the highest single-day death toll for any country since the outbreak began.

The Italian government has launched an all-out battle against its coronavirus outbreak: The entire country, home to over 60 million people, was put on lockdown.

March 17: A leaked federal plan warns the new coronavirus pandemic "will last 18 months or longer" and may come in "multiple waves" of infections.

The New York Times reported it had seen a 100-page federal plan, marked "For Official Use Only // Not For Public Distribution or Release," to tackle the ongoing pandemic.

The plan's forecast was dire. As Business Insider's Rosie Perper wrote, the plan reportedly said product shortages could exacerbate the current situation, "impacting health care, emergency services, and other elements of critical infrastructure."

It also allegedly said there may be "potentially critical shortages" of staffing, diagnostic capabilities, and medical supplies, including personal protective equipment and pharmaceuticals.

March 19: Globally, authorities reported more than 235,000 confirmed cases of COVID-19, with about 140,000 being active and ongoing cases, roughly 85,000 recoveries, and 10,000 deaths.

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