Coronavirus disease 2019 2020
2019-nCoV acute respiratory disease
Novel coronavirus pneumonia
Wuhan coronavirus, Wuhan virus, Wuhan pneumonia, Wuhan flu
“Coronavirus” or other names for SARS-CoV-2
Informally, sometimes simply “corona”
The spikes on the outer edge of the virus particles resemble a crown, giving the disease its characteristic name.
Specialty Acute respiratory infection
Symptoms Fever, cough, shortness of breath
Complications Pneumonia, ARDS, kidney failure
Risk factors Not taking preventative measures
Diagnostic method rRT-PCR testing, immunoassay, CT scan
Prevention Correct handwashing technique, cough etiquette, avoiding close contact with sick people or subclinical carriers
(3.4% of confirmed cases; significantly lower when non-reported cases are included)
Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
The disease was first identified in 2019 in Wuhan, China, and has spread globally, resulting in the 2019–20 coronavirus pandemic. Common symptoms include fever, cough and shortness of breath. Muscle pain, sputum production and sore throat are less common symptoms. While the majority of cases result in mild symptoms, some progress to pneumonia and multi-organ failure. The deaths per number of diagnosed cases is estimated at between 1% and 5% but varies by age and other health conditions
The infection is spread from one person to others via respiratory droplets, often produced during coughing and sneezing. Time from exposure to onset of symptoms is generally between 2 and 14 days, with an average of 5 days. The standard method of diagnosis is by reverse transcription polymerase chain reaction (rRT-PCR) from a nasopharyngeal swab or throat swab. The infection can also be diagnosed from a combination of symptoms, risk factors and a chest CT scan showing features of pneumonia
Recommended measures to prevent the disease include frequent hand washing, maintaining distance from other people and not touching one’s face. The use of masks is recommended for those who suspect they have the virus and their caregivers, but not the general public. There is no vaccine or specific antiviral treatment for COVID-19; management involves treatment of symptoms, supportive care, isolation and experimental measures.
The World Health Organization (WHO) declared the 2019–20 coronavirus outbreak a pandemic and a Public Health Emergency of International Concern (PHEIC). Evidence of local transmission of the disease has been found in many countries across all six WHO regions.
1 Signs and symptoms
5.1 Personal protective equipment
5.2 Mechanical ventilation
5.3 Experimental treatment
5.4 Information technology
5.5 Psychological support
6.1 Long-term health consequences
8.3 Passive antibody therapy
10 See also
12 External links
Signs and symptoms
Rate of symptoms
Dry cough 67.7%
Sputum production 33.4%
Shortness of breath 18.6%
Muscle pain or joint pain 14.8%
Sore throat 13.9%
Nausea or vomiting 5.0%
Nasal congestion 4.8%
Conjunctival congestion 0.8%
Those infected with the virus may either be asymptomatic or develop flu-like symptoms that include fever, cough and shortness of breath. Diarrhoea and upper respiratory symptoms such as sneezing, runny nose, or sore throat are less common. Cases can progress to pneumonia, multi-organ failure and death in the most vulnerable.
The incubation period ranges from two to 14 days, with an estimated median incubation period of five to six days, according to the World Health Organization (WHO). The median time from onset to clinical recovery for mild cases is approximately 2 weeks and is 3-6 weeks for people with severe or critical disease. Preliminary data suggests that the time period from onset to the development of severe disease, including hypoxia, is 1 week. Among people who have died, the time from symptom onset to outcome ranges from 2-8 weeks.
One study in China found that CT scans showed ground-glass opacities in 56%, but 18% had no radiological findings. 5% were admitted to intensive care units, 2.3% needed mechanical support of ventilation and 1.4% died. Bilateral and peripheral ground glass opacities are the most typical CT findings. Consolidation, linear opacities and reverse halo sign are other radiological findings. Initially, the lesions are confined to one lung, but as the disease progresses, indications manifest in both lungs in 88% of so-called “late patients” in the study group (the subset for whom time between onset of symptoms and chest CT was 6–12 days).
It has been noted that children seem to have milder symptoms than adults.
Main article: Severe acute respiratory syndrome coronavirus 2
The disease is caused by the virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), previously referred to as the 2019 novel coronavirus (2019-nCoV). It is primarily spread between people via respiratory droplets from coughs and sneezes.
Lungs are the organs most affected by COVID-19 because the virus accesses host cells via the enzyme ACE2, which is most abundant in the type II alveolar cells of the lungs. The virus uses a special surface glycoprotein, called “spike”, to connect to ACE2 and intrude the hosting cell. The density of ACE2 in each tissue correlates with the severity of the disease in that tissue and some have suggested that decreasing ACE2 activity might be protective, though another view is that increasing ACE2 using Angiotensin II receptor blocker drugs could be protective and that these hypotheses need to be tested. As the alveolar disease progresses respiratory failure might develop and death might ensue. ACE2 might also be the path for the virus to assault the heart causing acute cardiac injury. People with existing cardiovascular conditions have worst prognosis.
The virus is thought to have an animal origin, through spillover infection. It was first transmitted to humans in Wuhan, China, in November or December 2019, and the primary source of infection became human-to-human transmission by early January 2020. On 14 March 2020, South China Morning Post reported that a 55-year-old from Hubei province could have been the first person to have contracted the disease on 17 November 2019. As of 14 March 2020, 67,790 cases and 3,075 deaths due to the virus have been reported in Hubei province; a case fatality rate (CFR) of 4.54%.
Main article: COVID-19 testing
CDC rRT-PCR test kit for COVID-19
The WHO has published several testing protocols for the disease. The standard method of testing is real-time reverse transcription polymerase chain reaction (rRT-PCR). The test can be done on respiratory samples obtained by various methods, including a nasopharyngeal swab or sputum sample. Results are generally available within a few hours to 2 days. Blood tests can be used, but these require two blood samples taken two weeks apart and the results have little immediate value. Chinese scientists were able to isolate a strain of the coronavirus and publish the genetic sequence so that laboratories across the world could independently develop polymerase chain reaction (PCR) tests to detect infection by the virus.
As of 26 February 2020, there were no antibody tests or point-of-care tests though efforts to develop them are ongoing.
Diagnostic guidelines released by Zhongnan Hospital of Wuhan University suggested methods for detecting infections based upon clinical features and epidemiological risk. These involved identifying people who had at least two of the following symptoms in addition to a history of travel to Wuhan or contact with other infected people: fever, imaging features of pneumonia, normal or reduced white blood cell count, or reduced lymphocyte count. A study published by a team at the Tongji Hospital in Wuhan on 26 February 2020 showed that a chest CT scan for COVID-19 has more sensitivity (98%) than the polymerase chain reaction (71%). False negative results may occur due to PCR kit failure, or due to either issues with the sample or issues performing the test. False positive results are likely to be rare.
Typical CT imaging findings
CT imaging of rapid progression stage
See also: 2019–20 coronavirus pandemic § Prevention
An illustration of the effect of spreading out infections over a long period of time, known as flattening the curve; decreasing peaks allows healthcare services to better manage the same volume of people, and allows for more preparation time.
Alternatives to flattening the curve
Because a vaccine against SARS-CoV-2 is not expected to become available until 2021 at the earliest, a key part of managing the COVID-19 pandemic is trying to decrease the epidemic peak, known as flattening the epidemic curve. This helps decrease the risk of health services being overwhelmed and provides more time for a vaccine and treatment to be developed.
Preventive measures to reduce the chances of infection in locations with an outbreak of the disease are similar to those published for other coronaviruses: stay home, avoid travel and public activities, wash hands with soap and hot water often, practice good respiratory hygiene and avoid touching the eyes, nose, or mouth with unwashed hands. Social distancing strategies aim to reduce contact of infected persons with large groups by closing schools and workplaces, restricting travel and canceling mass gatherings.
According to the WHO, the use of masks is only recommended if a person is coughing or sneezing or when one is taking care of someone with a suspected infection.
To prevent transmission of the virus, the Centers for Disease Control and Prevention (CDC) in the United States recommends that infected individuals stay home except to get medical care, call ahead before visiting a healthcare provider, wear a face mask when exposed to an individual or location of a suspected infection, cover coughs and sneezes with a tissue, regularly wash hands with soap and water and avoid sharing personal household items. CDC also recommends that individuals wash hands often with soap and water for at least 20 seconds, especially after going to the toilet or when hands are visibly dirty, before eating and after blowing one’s nose, coughing, or sneezing. It further recommended using an alcohol-based hand sanitizer with at least 60% alcohol, but only when soap and water are not readily available. The WHO advises individuals to avoid touching the eyes, nose, or mouth with unwashed hands. Spitting in public places also should be avoided.