Chinese passengers arrive at a Beijing railway station amid the coronavirus outbreak. Kevin Frayer/Getty Images
A new coronavirus first reported in the Chinese city of Wuhan in late 2019 has spread worldwide, reaching more than one hundred countries by March 2020. It has infected more than 125,000 people and killed over four thousand.
The World Health Organization (WHO) declared the crisis a public health emergency and eventually designated it a pandemic. Governments around the globe have ramped up efforts to limit the virus’s spread, including quarantines, border closures, and intensified medical research. Many economies are already under stress as measures to contain the virus disrupt supply chains and bring some businesses to a halt.

What are coronaviruses? 

They are a family of viruses common in animals, including bats, camels, and cows, and can sometimes be transmitted to humans. They are named for the crown-like spikes on their surface, which scientists believe the virus uses to enter cells and delay the immune system’s response. Common symptoms of coronaviruses, including the new virus, are fever, cough, and shortness of breath; in more severe cases coronaviruses can cause kidney failure, acute respiratory illnesses such as pneumonia, and even death.

Have they caused outbreaks before?

Several coronaviruses have spread from animals to humans, leading to outbreaks in recent years. Middle East Respiratory Syndrome (MERS) was first transmitted to humans from camels in 2012 in Saudi Arabia. It has been fatal in one-third of patients, and has led to more than 850 deaths.

Until 2019, the most widespread coronavirus outbreak was that of Severe Acute Respiratory Syndrome (SARS). It was first reported in southern China in late 2002, and is believed to have been transferred to humans from civets, a cat-like species. An epidemic of SARS swelled across four continents in the months after its discovery, ultimately infecting more than eight thousand people across twenty-six countries and killing close to eight hundred before the virus was contained in July 2003.

On December 30, 2019, Chinese officials notified the WHO of an outbreak of a new coronavirus disease, known as COVID-19, that was first detected in the city of Wuhan, in the central province of Hubei. The virus rapidly spread across China, as well as to dozens of other countries, including the United States. By March, the death toll surpassed four thousand, far higher than the number of people killed during the SARS epidemic. Most of these deaths happened in China, though by that point many more new cases, including fatal ones, were being reported outside of China than within it.

How is the new virus transmitted?

Like other coronaviruses, it is transmitted primarily through close contact with an infected person. Droplets generated by coughing or sneezing, saliva, mucus, and fecal matter can carry the virus and transfer it to nearby people. Health experts believe contact within about six feet is typically required for transmission. They estimate that the virus can survive on surfaces for a few hours to several days.  Crucial aspects of the virus’s spread, including:

  • how contagious it is;
  • the time it takes for an infected person to show symptoms, known as the incubation period;
  • to what extent the virus can be spread by people showing no symptoms;
  • whether animal-to-human transmission is ongoing;
  • what animal the virus was first transmitted from; and
  • whether the virus can be passed down from pregnant mothers to their babies.

Older people and those with preexisting health conditions are believed to be more at risk of developing severe symptoms.

Is there a vaccine?

No medicines to prevent or treat the virus are currently available, though researchers in both the public and private sectors are searching for possible medications, including vaccines, to be tested in clinical trials. Officials at the U.S. National Institutes of Health said a vaccine would likely be ready to be administered to the public within twelve to eighteen months.

To lower the chances of getting sick, the WHO has urged people to wash their hands frequently, cover their noses and mouths when sneezing, and avoid anyone who appears sick. It advises anyone who is feeling sick or who was in close contact with someone who has the virus to call their medical providers. Wearing a medical mask can help limit the spread, though it is not necessary unless a person is coughing, suspected to have the coronavirus, or caring for someone suspected to have the virus. The U.S. Centers for Disease Control and Prevention (CDC) has also urged people to get flu shots and take similar precautionary measures, as a particularly deadly U.S. flu season has coincided with the coronavirus outbreak.

How deadly is the new coronavirus?

Scientists say it’s too soon to tell how deadly the virus is. They believe that a large number of cases worldwide likely have not been reported, which could lead to an artificially high or inaccurate fatality rate, the percentage of people who die after contracting the disease. WHO Director-General Tedros Adhanom Ghebreyesus said the global fatality rate was about 3.4 percent as of early March. In comparison, the fatality rate from the seasonal flu, which is in a different family of viruses, is about 0.1 percent, according to WHO estimates.

What has been China’s response?

When the first cases appeared in early December, Wuhan officials silenced doctors who warned of the new virus, and did not alert the public of a possible outbreak. (One of those doctors, Li Wenliang, later died from the virus.) By the time authorities issued warnings and alerted the WHO on December 31, the virus had already spread to an unmanageable level, experts say. Authorities closed an animal market where the virus was thought to have originated, but wildlife trading was not immediately banned throughout the city and province.

The virus spread rapidly. By January 30, every Chinese province had reported a case of the virus, cases appeared abroad, and 170 people had died, at which point Beijing, as well as local and provincial governments, took dramatic steps. Fifteen cities throughout Hubei Province were placed on full or partial lockdown, restricting the travel of more than fifty million people.

As the outbreak worsened, China faced shortages of medical workers and supplies, including diagnostic test kits and hospital beds. The central government sent thousands of medical personnel, including military doctors, to help. Thousands of health-care workers have contracted the disease and several have died. The central government was criticized for its initial slow response and later offered a rare admission of its “shortcomings and deficiencies,” vowing to improve the emergency management system. CFR’s Elizabeth C. Economy described the outbreak as “the worst humanitarian and economic crisis of [Chinese President Xi Jinping’s] tenure.”

By early March, the outbreak appeared to be slowing, with China reporting its fewest number of new cases since tracking began in January. China closed several makeshift hospitals in Wuhan that were built earlier in the year, and many schools started to reopen.

What is the rest of the world doing to contain the outbreak?

WHO. On January 30, the WHO declared the outbreak a public health emergency of international concern, and soon after shepherded a global preparedness and response plan that asks for $675 million in funding from donors to last through April. The plan seeks to facilitate research; improve country readiness, particularly where health systems are weak; and boost surveillance, among other measures. By March 11, donors had pledged just over $100 million for the plan, of which the WHO had received half. That same day, the WHO designated the outbreak a pandemic, urging countries to develop and implement national emergency plans to control the virus’s spread.

East Asia. By early March, South Korea had more than seven thousand cases. President Moon Jae-in issued a red alert, the country’s highest, which allowed the government to restrict domestic travel and lock down cities, and Seoul and Washington postponed joint military exercises. The government has conducted an estimated fifteen thousand tests per day, which experts believe has contributed to a relatively low number of deaths. Hundreds of passengers aboard the Diamond Princess cruise ship, which was quarantined in Japan for two weeks in February, tested positive for the virus. Japan closed schools through early April. Tokyo also said it planned to host the 2020 Summer Olympics as scheduled in July.

Southeast Asia. Southeast Asian countries, which largely depend on tourism and economic ties with China, have differed in their responses to the virus. By mid-March, Malaysia and Singapore each had more than one hundred cases, while the Philippines and Vietnam reported several dozen. The Philippines temporarily banned noncitizens who had recently visited China shortly before the first death from the virus outside China was reported there in early February. Vietnam closed its land border with China and temporarily barred most flights from mainland China. Singapore denied entry to all visitors who recently traveled to China and suspended visas for Chinese passport holders. In March, India announced it would suspend all tourist visas for at least one month.

Europe and Eurasia. The hardest-hit country outside China has been Italy, where the number of cases passed twelve thousand in March, leading the government to place its entire population of sixty million people on lockdown. The European Union, which has recorded thousands of cases in addition to Italy’s, has taken actions to contain the spread of the virus across its member states. In January, the bloc mobilized to bring hundreds of its citizens home from the Wuhan area. It also dedicated €10 million to investigate the virus, and later named five commissioners to lead a response team. The outbreak has raised questions about the bloc’s ability to work together: the Czech Republic, France, and Germany blocked exports of protective gear amid fears they could run out of supplies at home. Mongolia and Russia, two of China’s neighbors, closed their land borders until at least early March.

Middle East. Iran has had one of the highest death tolls outside China, with more than 350 killed, including several prominent political figures. The government closed schools and cultural centers in fourteen provinces. After cases linked to Iran were reported elsewhere in the Middle East, including in Bahrain and Iraq, several of Iran’s neighbors closed their borders with the country. Months ahead of the annual Hajj pilgrimage, Saudi Arabia suspended entry visas for foreigners planning to travel to the holy city of Mecca and other religious sites.

Sub-Saharan Africa. African countries have been on high alert, due to the expanded economic ties many of them have with China and concerns about their health systems’ capacity to deal with the virus. Many countries increased surveillance at airports and other ports of entry; some, including Kenya and Ethiopia, made quarantines mandatory for Chinese travelers. By March, however, relatively few cases had been reported across sub-Saharan Africa compared to other regions: just over two dozen cases in total had been confirmed from eight countries.

Latin America. In late February, Brazil confirmed its first case, marking the virus’s spread to all continents but Antarctica. By early March, several other countries in the region had reported cases, including Argentina, Chile, Ecuador, and Peru. Many governments said they were monitoring the situation and expanding testing at airports.

As fear of the virus grows, the United Nations and the WHO have worked to tackle disinformation that has fueled discrimination, racism, and xenophobia against Chinese people around the world. The CDC has urged people not to assume that someone of Asian descent is more likely to have the virus.

The United States declared the coronavirus outbreak a public health emergency in late January. As person-to-person spread was detected in other countries, the CDC said the virus would likely become a pandemic and start spreading in the United States, and it urged Americans to prepare for “significant disruptions,” including school and office closures. The response has been marred by the use of faulty test kits. By mid-March, more than 1,200 people in the country had contracted the virus, and at least thirty-six had died, according to the CDC.

The Donald J. Trump administration launched a coronavirus task force, which banned Chinese travelers and non-U.S. citizens who recently visited mainland China from entering the United States, and Vice President Mike Pence was tapped to oversee the U.S. response. The State Department evacuated U.S. citizens from Wuhan and issued travel advisories for China, Iran, Italy, Japan, and South Korea because of high numbers of cases there. Trump later announced a ban on most travel from Europe through mid-April, blaming the spread of the virus to the United States on the EU’s decision to not bar travelers from China and other hotspots. U.S. airlines, including Delta and United, canceled flights between highly affected countries and the United States.

The CDC has led the U.S. public health response, which has included expanding screenings of travelers at airports, quarantining sick patients, offering public health guidance, and deploying hundreds of personnel to assist state and local health departments. It developed a test to diagnose the virus, but its widespread use by health departments and hospitals was delayed after it sometimes produced inconclusive results.

In early March, Congress approved more than $8 billion of emergency funding for the outbreak, more than three times the amount requested by the White House. Around $3 billion will go to the Department of Health and Human Services, and close to $1 billion will be used to assist state and local health departments. Additionally, the Federal Reserve moved to calm panicked investors by injecting more than $1.5 trillion into the short-term lending market and expanding its bond-buying program, currently at $60 billion monthly, into longer-term Treasury bonds.

What are the economic consequences?

The outbreak has already disrupted global supply chains and global tourism, and affected markets for commodities such as oil. Months into the crisis, economic turmoil has sparked fears of a global recession, with Bloomberg analysts warning that the global economy could lose up to $2.7 trillion. For comparison, the SARS crisis caused the global economy to lose an estimated $40 billion in 2003. Growing alarm has sparked calls for a concerted financial response.

In China, which has already experienced an economic slowdown from the trade war with the United States, the government ordered thousands of restaurants, movie theaters, factories, and other businesses to close to prevent person-to-person transmission; some had reopened by the end of February. It encouraged people to avoid traveling and asked airlines and other transportation providers to issue refunds. Experts say economic growth could slow dramatically in the first quarter of 2020.

Demand for oil has plummeted in China—the world’s biggest oil importer—and around the world. In early March, the Organization of the Petroleum Exporting Countries (OPEC) failed to reach a deal on production cuts, causing oil prices to fall to their lowest level since 1991. The closure of Chinese factories has disrupted the supply chains for vehicles, jets, pharmaceuticals, and smartphones, among other products. For example, Hyundai slowed production at its factories in South Korea because of a lack of parts from China. The outbreak has devastated the tourism industry, including hotels and air and cruise lines. Around the world, conferences, concerts, sporting events, and other large gatherings were postponed or canceled. The U.S. National Basketball Association and the National Hockey League suspended their seasons.


Think Global Health, a CFR initiative, analyzes regional responses to the coronavirus outbreak.

In Foreign Affairs, CFR’s Yanzhong Huang writes that distrust of the U.S. and Chinese governments has led to the spread of coronavirus conspiracy theories.

The CDC shares information, including recommendations for the public, on its website.

The WHO provides daily updates and guidance regarding the outbreak on its novel coronavirus page.

The Johns Hopkins Center for Systems Science and Engineering maps coronavirus cases throughout the world.

The New York Times documents life in Wuhan during the city’s lockdown.