2019 Novel Coronavirus (2019-nCoV) (COVID-19)

Updated: Feb 14, 2020
  • Author: David J Cennimo, MD, FAAP, FACP, AAHIVS; Chief Editor: Michael Stuart Bronze, MD  more...
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Overview

Practice Essentials

2019-nCoV is a novel coronavirus that was first identified amid an outbreak of respiratory illness cases in Wuhan City, Hubei Province, China. [1] It was initially reported to the WHO on December 31, 2019. On January 30, 2020, the WHO declared the 2019-nCoV outbreak a global health emergency. [2, 3]

Illness caused by 2019-nCoV is now termed COVID-19 by the WHO, the new acronym derived from "coronavirus disease 2019." The name was chosen to avoid stigmatizing the virus's origins in terms of populations, geography, or animal associations. [4, 5]  On February 11, 2020, the Coronavirus Study Group of the International Committee on Taxonomy of Viruses issued a statement announcing an official designation for 2019-nCoV: severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). [6]

2019-2020 Outbreak

As of February 14, 2020, COVID-19 has been confirmed in more than 64,000 individuals (mostly in China) and has resulted in more than 1300 deaths. Outside of China, infections have been reported in an increasing number of countries, including Hong Kong, Macau, Taiwan, Australia, Belgium, Cambodia, Canada, Finland, France, Germany, India, Italy, Japan, Malaysia, Nepal, Philippines, Russia, Sri Lanka, Singapore, Spain, Sweden, Thailand, The Republic of Korea, United Arab Emirates, United Kingdom, United States, and Vietnam. [7]

In the United States, 15 cases have been reported as of February 14, 2020, in the states of Washington, Illinois, California, Arizona, Wisconsin, Texas, and Massachusetts. [8, 9] The Centers for Disease Control and Prevention (CDC) has concluded, at least currently, that the health risk in the United States is generally low, although they are taking proactive preparedness precautions. Person-to-person spread of 2019-nCoV has been reported in the United States. [10, 11] Individuals who believe they may have been exposed to 2019-nCoV should immediately contact their healthcare provider.

Currently, travellers from Wuhan, China, are undergoing entry screening at several major US airports, including Atlanta (ATL), Chicago (ORD), Los Angeles, (LAX) New York City (JFK), and San Francisco (SFO). [12] This number may increase as needed to screen travelers.

Healthcare personnel are also referred to the article Novel Coronavirus (2019-nCoV): Frequently Asked Questions for Clinicians.

Route of transmission

Transmission is believed to occur via respiratory droplets from coughing and sneezing, as with other respiratory pathogens, including influenza and rhinovirus. [13] According to the WHO, the spread of 2019-nCoV in China seems to be largely limited to family members, healthcare providers, and other close contacts and is probably being transmitted by respiratory droplets. WHO officials project that the outbreak is containable if that pattern holds. Severe cases in China have mostly been reported in adults older than 40 years old with significant comorbidities and have skewed toward men. [9] A family cluster of infections has been recently described, including a child with asymptomatic infection. [14]

An initial report of 425 patients with confirmed COVID-19 in Wuhan, China, attempted to describe the epidemiology. Many of the initial cases were associated with direct exposure to live markets, while subsequent cases were not. This further strengthens the case for human-to-human transmission. The incubation time for new infections was found to be 5.2 days, with a range of 4.1-7 days. The longest time from infection to symptoms seemed to be 12.5 days. At this point, the epidemic had been doubling approximately every 7 days, and the base reproductive number was 2.2 (meaning every patient infects an average of 2.2 others). [15] Further data will likely better define the clinical course, incubation time, and duration of infectivity.

Diagnostic testing

The CDC has developed a diagnostic test for detection of the virus and has requested special emergency authorization from the FDA for its use. [16] The test is a real-time reverse transcription–polymerase chain reaction (rRT-PCR) assay that can be used to diagnose the virus in respiratory and serum samples from clinical specimens. [12]

Of note, commercially available molecular tests for respiratory viruses (even those detecting endemic coronaviruses) have not demonstrated the ability to detect 2019-nCoV. Australian scientists have successfully grown the virus in cultures. [17]

Treatment of COVID-19

No specific antiviral treatment is recommended for COVID-19. Infected patients should receive supportive care to help alleviate symptoms. Vital organ function should be supported in severe cases. [18]

No vaccine is currently available for 2019-nCoV. Avoidance is the principal method of deterrence.

Infection control

Patients who are under investigation for 2019-nCoV infection should be evaluated in a private room with the door closed (an airborne infection isolation room is ideal) and asked to wear a surgical mask. All other standard contact and airborne precautions should be observed, and treating healthcare personnel should wear eye protection. [19]

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Background

Coronaviruses comprise a vast family of viruses, 7 of which are known to cause disease in humans. Some coronaviruses that typically infect animals have been known to evolve to infect humans. 2019-nCoV is likely one such virus, postulated to have originated in a large animal and seafood market. Recent cases involve individuals who reported no contact with animal markets, suggesting that the virus is now spreading from person to person. [20]

Severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) are also caused by coronaviruses that “jumped” from animals to humans. More than 8,000 individuals developed SARS, nearly 800 of whom died of the illness (mortality rate of approximately 10%), before it was controlled in 2003. [21] MERS continues to resurface in sporadic cases. A total of 2,465 laboratory-confirmed cases of MERS have been reported since 2012, resulting in 850 deaths (mortality rate of 34.5%). [22]

The full genome of 2019-nCoV was first posted by Chinese health authorities soon after the initial detection, facilitating viral characterization and diagnosis. [12] The CDC analyzed the genome from the first US patient who developed the infection on January 24, 2020, concluding that the sequence is nearly identical to the sequences reported by China. [12] 2019-nCoV is a group 2b beta-coronavirus that has at least 70% similarity in genetic sequence to SARS-CoV. [22]

Prognosis and Severity of COVID-19 Compared With SARS and MERS

Early reports have described COVID-19 as clinically milder than MERS or SARS in terms of severity and case fatality rate. [22] Thus far, the fatality rate for COVID-19 appears to be around 2%. [9]

Early in the outbreak, WHO reported that severe cases in China had mostly been reported in adults older than 40 years old with significant comorbidities and skewed toward men, although this pattern may be changing. [9]

In an initial report of 41 patients infected in Wuhan, China, Huang et al reported a 78% male predominance, with 32% of all patients reporting underlying disease. The most common clinic finding was fever (98%), followed by cough (76%) and myalgia/fatigue (44%). Headache, sputum production, and diarrhea were less common. The clinical course was characterized by the development of dyspnea in 55% of patients and lymphopenia in 66%. All patients with pneumonia had abnormal lung imaging findings. Acute respiratory distress syndrome (ARDS) developed in 29% of patients, [23] and ground-glass opacities are common on CT scans. [14]

History, Symptoms of Infection, and Potential Complications

Although data are limited early in the 2019-nCoV outbreak, presentations of the illness have ranged from asymptomatic/mild symptoms to severe illness and mortality. Symptoms may include fever, cough, and shortness of breath. [24] Other symptoms, such as malaise and respiratory distress, have also been described. [22]

Symptoms may develop 2 days to 2 weeks following exposure to the virus. [24] Although initial reports have centered on patients with severe illness leading to hospitalization, milder and even asymptomatic cases may be possible. Further research is needed to address the full spectrum of clinical illness.

Clinicians evaluating patients with fever and acute respiratory illness should obtain information regarding travel history or exposure to an individual who recently returned from China. [25]

Patients with suspected COVID-19 should be reported immediately to infection-control personnel at their healthcare facility and the local or state health department. Current CDC guidance calls for the patient to be cared for with airborne and contact precautions (including eye shield) in place. [19] Patient candidates for such reporting include those with fever and symptoms of lower respiratory illness who have travelled from Wuhan City, China, within the preceding 14 days or who have been in contact with an individual under investigation for COVID-19 or a patient with laboratory-confirmed COVID-19 in the preceding 14 days. [25]

Early in the outbreak, one patient with COVID-19 (a 61-year-old man with an underlying abdominal tumor and cirrhosis) was admitted with severe pneumonia and respiratory failure. Complications of infection included severe pneumonia, septic shock, acute respiratory distress syndrome (ARDS), and multiorgan failure, resulting in death. [22]

Diagnostic Testing and Workup

Currently, diagnostic testing for 2019-nCoV can be conducted only by the CDC. [13]

State health departments with a patient under investigation (PUI) should contact CDC’s Emergency Operations Center (EOC) at 770-488-7100 for assistance with collection, storage, and shipment of clinical specimens for diagnostic testing by the CDC. Specimens from the upper respiratory tract, lower respiratory tract, and serum should be collected to optimize the likelihood of detection. [25]

Laboratory testing

If laboratory testing confirms an alternate pathogen, 2019-nCoV can be excluded, although this recommendation may change in the future. [26]

The CDC has developed a diagnostic test for detection of the virus and has requested special emergency authorization from the FDA for its use. [16] The test is a real-time reverse transcription–polymerase chain reaction (rRT-PCR) assay that can be used to diagnose the virus in respiratory and serum samples from clinical specimens. [12]

In patients with suspected COVID-19, virus isolation in cell culture or initial characterization of viral agents recovered in cultures of specimens is not recommended for biosafety reasons. [25]

Leukopenia and lymphopenia were common among early cases. [22, 23]

Chest radiography

Chest radiography may reveal pulmonary infiltrates. [27]

CT scanning

CT scan may reveal ground-glass infiltrates or consolidation, almost always bilateral. [23]

Treatment and Prevention of COVID-19

No specific antiviral treatment is recommended for COVID-19. Infected patients should receive supportive care to help alleviate symptoms. Vital organ function should be supported in severe cases. [18]

No vaccine is currently available for 2019-nCoV. Avoidance is the principal method of deterrence.

General measures for prevention of viral respiratory infections include the following: [18]

  • Handwashing with soap and water for at least 20 seconds. An alcohol-based hand sanitizer may be used if soap and water are unavailable.
  • Individuals should avoid touching their eyes, nose, and mouth with unwashed hands.
  • Individuals should avoid close contact with sick people.
  • Sick people should stay at home (eg, from work, school).
  • Coughs and sneezes should be covered with a tissue, followed by disposal of the tissue in the trash.
  • Frequently touched objects and surfaces should be cleaned and disinfected regularly.

Infection control

Patients who are under investigation for COVID-19 should be evaluated in a private room with the door closed (an airborne infection isolation room is ideal) and asked to wear a surgical mask. All other standard contact and airborne precautions should be observed, and treating healthcare personnel should wear eye protection. [19]

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