1Question : What exactly is COVID-19 (Coronavirus disease 2019)?
COVID-19 is an infectious disease caused by a virus of the Coronaviridae family. The scientific name of the virus (Severe Acute Respiratory Syndrome CoronaVirus 2 = SARS-CoV-2) comes from the severe pneumonia that it may cause in susceptible individuals. The coronaviruses are largely found in animals and have only recently spread to man. Because this is a new disease, there are uncertainties still.
Earlier coronavirus outbreaks causing serious illness were: SARS-CoV (2002/2003 in China) and MERS (Middle East Respiratory Syndrome)-CoV (2012, mainly in Saudi Arabia).
- Description: RNA virus with a protective cover of proteins.
- Effects: infection of the chest and lungs, ranging from fever and dry cough to severe pneumonia.
- Spread to Man: from bats to pangolin (a scaly anteater found in Asia and parts of Africa), and now to humans; then it spreads from human to human.
2Question: Do we have any immunity?
As this is a new virus in man, it is not thought we have any natural immunity. We usually develop some immunity after viral illnesses but at present the degree of immunity after a coronavirus infection is not yet well known.
It is too early to know exactly how long the immunity developed by humans to the SARS-CoV-2 will last. Experimentally, mice have been shown to develop protective immunity and this opens the road for the development of a vaccine.
Like all coronaviruses, SARS-CoV-2 might mutate frequently as the disease spreads in the population. We do not know yet whether these mutations will modify the infectivity or the severity of the illness.
3Question : What are the symptoms?
The main symptoms of the disease are: fever, non-productive cough, shortness of breath, joint and muscle pain, headache, malaise, sore throat, diarrhea and less often vomiting, and skin lesions. The loss of smell and taste early in the illness is an unusual and distinctive feature.
The Incubation period is 5 - 6 days during which there are usually no symptoms. The average duration of symptoms is around 14 days.
COVID-19 infection may be totally asymptomatic, perhaps in more than 50% of cases. These people who have no symptoms at all may nevertheless transmit the virus. We will know this better when we have widespread testing available for the population.
The severity of the disease is very variable, ranging from mild illness to severe pneumonia and sepsis (shock).
The mortality rate appears to be significantly higher than for usual seasonal influenza.
4Question: How is the diagnosis made?
Clinical symptoms are sometimes quite suggestive, particularly if there has been contact with someone with known COVID-19. The diagnosis is supported by laboratory tests.
5Question: What are the different tests available and their reliability?
The diagnostic test which is the most widely used is by identifying the virus from a swab taken from the nose or throat using a technique called PCR (Polymerase Chain Reaction) . This method reveals the genetic material of the virus and is highly reliable, if taken at the right time.
Other fast blood tests are being developed to detect the presence of antibodies to the virus that are associated with the development of immunity. Isolation of Immunoglobulin M (IgM) antibodies at an early stage can confirm diagnosis of the disease and, some weeks later, the development Immunoglobulin G (IgG) antibodies can confirm that the individual has had the disease, even if it was not diagnosed at the time.
6Question: Why is isolation so important? Why are there different recommendations in different countries?
As coronavirus, like most infectious diseases, spreads from one human to another it makes sense for anyone with symptoms should avoid contact with other people. There are different policies between countries about how exactly this should be regulated due to different healthcare systems, organizations and cultures. Differences especially arise where the use of blood tests are concerned.
Some nations are or have been faced with shortage of proper face masks, intensive care beds, ventilators.
7Question: How is the virus transmitted?
Transmission of the virus occurs through people and objects. The main mode of transmission is due to direct spread of respiratory droplets (coughing, sneezing, talking face-to-face at close distance) and by touching contaminated surfaces. Some uncertainties remain about the way of transmission of the virus.
What is the survival of the virus outside the human body? The virus can survive for hours on surfaces: metal, tissues and plastic material. The virus can easily be destroyed by carefully washing hands using soap and water or common disinfectants.
To avoid infection from contaminated surfaces, it is very important to avoid touching your face, which many people do without being aware of it, whenever you are outside in public spaces, unless you wash your hands or use a hand sanitiser first.
8Question: Why are we in quarantine?
In order to prevent transmission of the virus to people who has been in close contact with person who is carrying the infection. Individuals with respiratory symptoms are more likely to transmit the virus than people with none.
By isolating much of the general population, it is hoped to interrupt the chain of transmission of the virus. This would avoid a sudden peak of ill patients needing hospitalization, including intensive care, at the same time, which could rapidly overwhelm the capacity of hospitals. Social isolation is the most effective way to prevent virus spread.
9Question: Do we need face masks?
As the virus is spread by droplets from the nose and mouth, protective masks and clothing are essential for health workers looking after patients with the disease (personal protection equipment, PPE). Face masks are also recommended for people at home or outside in the case of people suspected of having the illness without test confirmation.
However, the wearing of face masks by the general public as the protection against contracting the virus is widely recommended. Gloves are recommended in case of handling food or other material susceptible to contamination.
10Question: What treatment is available?
Paracetamol is recommended for fever and joint and muscle aches. Supportive treatment of which oxygen is mainstay. Ventilator support in case of respiratory failure.
Unfortunately, there are no proven treatment available against the virus itself. Some antiviral medications (such as ritonavir or lopinavir) have been tested without success. Another antiviral drug, remdesivir, is being studied and appears to be promising.
A combination of the antibiotic azithromycin plus the antimalarial drug hydroxychloroquine has been proposed and is still under study, but is nonetheless being used in many countries. A powerful anti-inflammatory drug (anti-Interleukine-6), tocilizumab has been used in severe cases and is being studied.
Finally, administration of plasma from recovered patients, presumably containing neutralizing antibodies against the virus, holds some promise and is currently being tested.
Until now no drug/treatment has been officially approved. Many clinical trials are in progress. Work on vaccine development is ongoing, and hopefully a vaccine will be available in the future.
11Question: What is the course of the illness in severe cases?
Of the patients severe enough to be admitted to hospital, a significant proportion require intensive care, when the disease spreads throughout the lungs making it increasingly difficult to breathe. They then require artificial respiration using a ventilator, and it is a shortage of these machines that has made treatment so difficult at the peak of the epidemic. The duration of stay in the intensive care unit is 22 - 24 days.
The death rate depends on the severity of the illness. Recent data indicate overall mortality in the range of 0.5 – 5 %, while in critically patients the mortality rate may be as high as 60 %. These figures probably will change over time.
Why do patients die? Respiratory failure (mainly), cardiac complications and overwhelming infection/sepsis.
Who is most at risk? The elderly and frail; those with underlying chronic disorders (hypertension, diabetes, obesity, chronic cardiovascular or respiratory disorders, and cancer). Men are twice as likely to get coronavirus infections than women.
When do patients die? Usually after the second week of severe illness.
12Question: Does the spread of the virus decrease with heat?
The prefered temperature of the virus is around 8 degrees Celsius. With much higher temperature the virus may eventually fade out, but this is still speculative.
13Question: Can an infected person catch the virus again without it mutating, and if so, would the attack be more severe?
At this stage there are no existing data suggesting that a person could be reinfected. Some cases of suspicious reinfections have been described, but they were probably people that never cleared the virus from their body.
14Question: Are there people who have a natural immunity to this virus?
Females seem to have a lower risk of developing a severe form of illness. Some initial data seems also to suggest that people with blood group O are at lower risk for more severe forms of illness.
15Question: Is there any kind of international collaboration in medicine that is effective?
There are multiple examples of strong international collaboration, including at the level of the WHO and European agencies. Moreover there are European and National and International infectious disease and internal medicine societies. Obviously, ,this pandemic was not expected because the previous SARS and MERS outbreaks have been more localized and the last pandemic occurred more than 100 years ago (Spanish flu). If we had been better prepared, the impact of the pandemic would indeed probably have been smaller.