The new coronavirus (COVID-19) infection, which began in China in late 2019, is spreading worldwide. As more and more people are infected from all over the world, “fake news” related to this has made many people nervous. Here are 10 questions and answers that are most commonly asked and answered to help you get a better understanding of the new coronavirus COVID-19.
1. What is COVID-19 from China and how is it different from previously known viruses?
Coronavirus is a common virus that causes colds in humans. These human coronaviruses (CoVs) evolve over time and adapt to humans, causing only mild symptoms such as colds. However, this time, COVID-19 is a type of animal-derived coronavirus that has passed directly from animal to human, that is, across the species barrier. Examples include SARS-CoV, which was transmitted from bats to musk cats in 2003, and then spread to humans, and MERS-CoV, which was spread from bats to camels in 2015 and spread to humans.
A bat-derived coronavirus with the gene most similar to the newly emerged COVID-19 was discovered. However, it has not been determined whether the virus has passed directly from a bat to humans, or whether there are other wild animals as intermediate hosts, as in the previous examples.
Among the existing coronaviruses, the gene is 78% identical to the SARS coronavirus, but the spike protein gene that COVID-19 uses to attach to human cells is different from the SARS coronavirus. Therefore, it is thought that it has different biological characteristics from SARS coronavirus. In other words, unlike the SARS coronavirus, COVID-19 still has a lot of unknowns about how quickly it spreads, what transmission characteristics it has, clinical symptoms, and mortality.
2. How do you get infected? What are the symptoms?
The exact path of propagation requires further study, but is believed to be transmitted by droplets and contact. If an infected patient speaks or coughs, small droplet particles can reach 1 to 2 m. At this time, the droplets go directly into another person’s respiratory tract or are buried in a desk or a handle, etc., and then come into contact with another person’s hand and enter the mucosa or respiratory tract again. For COVID-19, there have been no reports of suspected airborne infections.
According to data from a recent analysis of 1,099 Chinese patients infected with COVID-19, about half of them had fever. However, it is known that most of the hospitalized patients (88%) have fever. It is unusual that fever is not pronounced at the beginning of the disease, as compared to SARS and MERS. Other symptoms include dry cough, body aches, acute helplessness, and difficulty breathing. In other words, it is presumed that fever is not pronounced at the beginning of the disease, there are mild symptoms similar to colds, and then symptoms such as fever appear.
3. Are asymptomatic infections likely to spread the virus?
Recently, patients with COVID-19 infection have been reported who have no symptoms and are not apparent on simple chest radiographs, but computed tomography (CT) scans have confirmed pneumonia. In addition, according to a paper published in the New England Journal of Medicine (NEJM) on January 30, 2020, cases of secondary infection of two Germans by Chinese traveling from Shanghai to Germany were reported. The Chinese contacted the Germans two or three days before the onset of symptoms. The Chinese stated that there were only symptoms of a little unwell due to jet lag. In short, the infected person has been infected with the COVID-19 virus 2 to 3 days before the onset of symptoms. Therefore, data suggests that COVID-19 may spread from mild symptoms without obvious symptoms such as fever.
A patient in Korea is also believed to have been transmitted from a daughter-in-law who has only mild cough symptoms after visiting Guangdong, China. This is very different from the SARS and MERS coronaviruses, which start spreading after the fever has occurred. It is clear, however, that there are some cases of transmission in patients with no apparent symptoms such as fever, but it is presumed that these minor patients do not constitute an important part of the widespread transmission of the community. However, this part has different epidemiological characteristics from SARS and MERS, so it is necessary to further study the infectivity in mild symptoms.
4. Is COVID-19 transmission through eye or skin contact possible?
Coronavirus has the ability to stay alive longer when buried on a desk or handle than the influenza virus. So, if we touch a contaminated desk or handle, it can spread. A contaminated hand with a virus comes into contact with the mucous membrane, such as the eye, or the nose or mouth, and the virus enters the respiratory system. Therefore, care for hand hygiene with a hand sanitizer can help prevent infection. It does not enter the human body directly through the skin.
5. Can pets transmit COVID-19?
Because each animal has different viral receptors in the respiratory tract, infecting humans does not mean that it can infect pets. In the case of SARS and MERS coronaviruses, for example, mice do not have a receptor that accepts them.
6. Are infectious and mortality rates lower than SARS-CoV or MERS-CoV?
It is known that the MERS mortality rate is about 20% and the SARS mortality rate is around 10%. However, caution is required for interpretation. Patients with MERS were older and had more underlying diseases than patients with SARS.
The age and underlying disease of patients infected with COVID-19 seems to be similar to SARS. The current confirmed mortality rate for COVID-19 is around 2-3%.
Mortality among patients in Wuhan, Hubei, China is much higher than in other regions. It is estimated that the death rate is high due to the lack of medical staff and facilities to care for the critically ill as the number of patients suddenly increases in Wuhan. In addition, outside of Wuhan, we are experiencing so-called travel-related infections and limited community outbreaks associated with them. In other words, it can be interpreted as having a low mortality rate outside of Wuhan, as infections occur in relatively healthy adults and are detected early and can be treated in a timely manner.
In general, infectious diseases tend to have a lower mortality rate (e.g. swine flu, measles) as the infectivity increases, and a higher mortality rate (e.g., MERS, H5N1) as the infectivity decreases. What matters here is the total number of deaths rather than the fatality itself. In other words, if the mortality rate is very high even if the mortality rate is low, the impact on us is inevitable because many people are infected and eventually the number of deaths increases.
Although the exact mortality rate of COVID-19 is currently unknown (estimated between 0.1% and 5%), it has already been confirmed that the infection rate is high. In addition, there are currently no antiviral drugs and vaccines.
7. The effect of wearing a mask is controversial. What is the most effective way to prevent COVID-19 transmission?
First, there are currently no treatments and vaccines for COVID-19. Therefore, it is most important to prevent viral infections through personal hygiene measures such as wearing a mask and hand hygiene.
For masks, disposable masks are most effective. It is also important to keep your hands away from contaminated areas on the front of the mask when removing it. If you think your hands are contaminated, we recommend disinfecting your hands immediately.
In general situations other than tracheal intubation or high-risk patient care, surgical and N95 masks are known to have the same protective effect against viruses. The N95 mask must be properly applied to the face for maximum effect. However, it is important to note that wearing N95 masks in real time often feels cramped, so long-term wearing is not easy.
8. Is the place (hospital, restaurant, etc.) that the patient has passed by is safe after disinfection?
Coronavirus can survive in the environment for a long time, but is quickly removed with heat and disinfectants. Even where the confirmed patient has passed, you can rest assured that it will be safe if it has been properly disinfected.
9. How far have treatments and vaccines been developed for COVID-19?
There are currently no treatments and vaccines. There are reports that some other treatments, such as HIV treatments, are effective, but this is not yet established and there are practically no treatments available. Treatments and vaccines take a long time to develop, so it is impossible to use them to end the current epidemic.
10. Should I refrain from seminars or meetings?
It is advisable to refrain from gathering people as much as possible, as there are currently reports of cases of community infection even in people with less pronounced symptoms.