This article was published by the Yale School of Medicine and written by Kathy Katella
While doctors need to learn more, it’s important to take precautions.
At the end of last year, an unusual outbreak of pneumonia in China presented a medical mystery that has been solved, in part at least, with the identification of a never-before-seen coronavirus. Though some people are using the broad term “coronavirus,” this particular one is known as the 2019 novel coronavirus. Many more questions are yet to be answered.
As doctors, epidemiologists, and medical researchers work to learn more about the new coronavirus, including such basic questions as how dangerous it is, how it spreads, and how it should be treated, people are understandably on edge as thousands of cases have been identified in China and the number of deaths continues to climb. The World Health Organization declared the new coronavirus to be a global health emergency as cases were reported internationally in a growing number of countries, including the United States.
The U.S. State Department issued its highest travel alert warning Americans not to travel to China, and warned travelers that new restrictions may be made with little or no notice. It advised Americans in China to leave using commercial transportation. Meanwhile, Chinese officials have put restrictions on travel and other activities in the area of Wuhan and throughout the country.
Relatively little is known about the 2019 novel coronavirus at this point, and there is no standard diagnosis, medication, or other treatments beyond making sure a patient gets enough hydration and oxygen. “Mostly, the advice is stay tuned, but here in the U.S., don’t unduly worry about it,” says Joseph Vinetz, MD, a Yale Medicine infectious disease specialist. “The bottom line is that there is a new flu-like bug. With a new virus in a culture dish, they can start looking at the biology and making drugs to treat it. Viral sequences have become available and will jump-start understanding the biology of this virus, including diagnosis and spread in human populations.”
The Centers for Disease Control and Prevention (CDC) still considers the risk from the virus to the American public to be low, and investigations are underway to learn more about the disease. “We really don’t know much yet,” Dr. Vinetz says, adding that there is no indication yet that the 2019 novel coronavirus is worse than influenza. “This is a time of watchful waiting.”
1. This is a new illness that doctors have never seen before
The name coronavirus refers to spikes seen (under a microscope) on the surface of the virus (corona is the Latin word for crown). Coronaviruses cause respiratory tract illnesses that range from the common cold to such potentially deadly illnesses as severe acute respiratory syndrome (SARS), also first identified in China, and Middle East Respiratory Syndrome (MERS).
Until SARS was identified, coronaviruses known as 0C43 and 229E, were the only known coronaviruses causing human infections. (OC43 and 229E are frequent causes of the common cold.) After the SARS coronavirus was identified, other coronaviruses, namely NL63 and HKU, were identified and have been found to cause human infections worldwide.
The 2019 novel coronavirus is a coronavirus that scientists haven’t seen before. Like other viruses—including Ebola (a deadly infectious disease that originated in Africa) and influenza—it is believed to have started in animals and spread to humans.
2. The virus is contagious, even before symptoms appear
Many of the first people to be diagnosed with the new coronavirus were linked in some way to a large animal and seafood market in Wuhan,which suggests animal-to-person transmission. The CDC now says there is evidence that the virus is able to spread person-to-person, though the exact mechanism for transmission is still unclear.
“We don’t know how contagious it is,” Dr. Vinetz says. “We don’t know how casual the contact has to be or how close the contact has to be.”
The CDC believes the new virus is contagious during the incubation period, which is believed to be 14 days, and symptoms can appear anytime between two and 14 days after exposure. Chinese officials reported person-to-person transmission as the virus spreads there. The CDC also has confirmed person-to-person transmission in the U.S.
According to the CDC, human coronaviruses are common throughout the world, and there are several known coronaviruses that can infect people, making them sick. Experience with those illnesses is informing our attempts to understand of this one. With SARS and MERS, transmission was thought to be similar to influenza, spreading among people in the vicinity of an infected person who spreads respiratory droplets by coughing or sneezing.
3. The 2019 novel coronavirus may be mild—but, in some cases, can be very serious
Scientists say it’s possible that the 2019 novel coronavirus is a mild one that often causes mild symptoms that are slower to develop than symptoms in SARS and MERS. However, similar to other infectious diseases, older adults and people who have underlying health conditions are considered to be at increased risk for more severe symptoms. The symptoms that have been identified so far include:
- Fever
- Cough
- Difficulty breathing that can be severe enough to cause people to seek hospital care
As with a cold, there is no vaccine for the coronavirus—and a flu vaccine won’t protect people from developing it. To protect yourself from the 2019 novel coronavirus, Dr. Vinetz says, “The best thing you can do at this point is take care of yourself the way you would to prevent yourself from getting the flu. You know you can get the flu when people sneeze and cough on you, or when you touch a doorknob. Washing hands—especially after eating, going to the bathroom, and touching your face—and avoiding other people who have flu-like symptoms are the best strategies at this point.”
4. We don’t know what we don’t know, so precautions are extremely important
Given that the symptoms tend to be mild and the number of people infected worldwide remains small, you may wonder why so much attention is being paid to this particular illness. For one thing, public health specialists are mapping exponential growth in infections worldwide and expect that the rate will continue to climb, given the long incubation period. Second, extreme caution is warranted because of how little is known about this new virus. New diseases aren’t discovered often and some (such as Ebola) turn out to be deadly. For now, spreading awareness, keeping people updated as scientists learn more, and screening people who might be at risk are the best tools available. So, if you travel or if you visit a health care provider or facility, it may be helpful to know that the coronavirus-related signs you see and questions you may be asked are important.
Since threats like the 2019 novel coronavirus can lead to the circulation of misinformation, it’s important to trust information only from reputable health organizations and government sources such as the CDC.
5. Guidelines will evolve as doctors learn more
Here’s the latest information everyone should have to minimize the risk of exposure to the 2019 novel coronavirus. Because knowledge about the new virus is evolving rapidly, you can expect recommendations to change, sometimes on a daily basis.
The CDC advises people who travel anywhere, locally or internationally, to:
- Avoid contact with sick people
- Avoid animals, whether they are dead or alive, as well as animal markets, and animal products
- Wash hands often with soap and water for at least 20 seconds. If soap and water are not available, use an alcohol-based hand sanitizer.
The CDC is conducting public health entry screenings of passengers on direct and connecting flights from Wuhan, China, at several U.S. airports, including John F. Kennedy in New York.
Anyone who has traveled to Wuhan and is experiencing fever or respiratory symptoms should:
- Seek medical care immediately. Call ahead to their doctor or emergency room to let them know about recent travel and symptoms.
- Avoid contact with others
- Avoid travel if they are sick
- Cover their mouth and nose with a tissue or sleeve (not hands) if they must cough or sneeze
- Wash hands often with soap and water for at least 20 seconds. If soap and water are not available, use an alcohol-based hand sanitizer.
Infection prevention specialists at Yale Medicine and Yale New Haven Health and other hospitals are now recommending the screening of patients with acute respiratory infections to determine whether they have been to Wuhan within the 14 days before they got sick, or if they’ve been exposed to anyone who may have been ill due to the 2019 novel coronavirus.
While the risk in Connecticut is considered to be low at this point, a doctor who suspects a patient may have the virus will follow standard infection control procedures. This includes giving the patient a face mask and putting them into their own room (if possible, an airborne infection isolation, or negative pressure room designed to contain airborne pathogens). Staff caring for these patients will notify infection prevention specialists immediately, while also wearing special face masks and taking other measures to avoid infecting themselves or others.
While there is no vaccine for coronavirus, public health authorities strongly advise everyone to get their annual flu shot if they have not done so already. In addition to preventing or mitigating the severity of flu, the vaccine will simplify the evaluation of patients with flu-like symptoms if potential cases of 2019 novel coronavirus surface in the community.
For more information, visit Yalemedicine.org.
[Originally published: January 23, 2020. Updated: January 31, 2020.]