Coronaviruses correspond to a group of viruses belonging to the Coronaviridae family that is responsible for respiratory infections that may be mild or severe enough, depending on the coronavirus responsible for the infection.
Most coronaviruses do not infect people or cause disease, however, there are two types that were associated with severe respiratory diseases, or SARS-CoV and MERS-CoV, responsible for the Severe Respiratory Syndrome and the Middle East Respiratory Syndrome respectively. Recently, another type of coronavirus named COVID-19 was identified and is related to respiratory diseases in China; This virus has also been identified in Thailand, Japan, South Korea, and the United States.
Coronaviruses can be transmitted from animals to people, which is what happens most frequently, but they can also be transmitted from person to person, as in the case of COVID-19. The symptoms are similar to those of the flu, however, in the case of viruses transmitted from animals to people, gastrointestinal symptoms may also appear.
Types of Coronavirus
7 types of coronaviruses are known, which are:
Type COVID-19 (Coronavirus of China)
This type of coronavirus is the most recent and was first identified in China, however, there are already reported cases of infection with this type of coronavirus in Thailand, Japan, South Korea, the United States, and Canada. There is not much information about this type of coronavirus yet, however, it is known that it also causes a serious respiratory infection, which can cause respiratory failure and cause death, as also occurs in the SARS-CoV and MERS-CoV viruses.
In relation to the transmission of this type of virus, it was found that people who went to a Wuhan market in China, where wild animals were marketed, were infected by the virus, checking the transmission of animal for the person. However, other people, who were not present in the market but who were in contact with sick people, were also infected with this same virus, confirming the hypothesis that the coronavirus of the type COVID-19 is also transmitted from person to person through the inhalation of respiratory drops and direct contact, without proper precautions with infected people.
Types 229E, NL63, OC43 and HKU1:
Normally, these types are associated with common colds and are responsible for mild respiratory diseases, which are naturally fought by the immune system itself. These types of viruses are transmitted from person to person and cause the appearance of typical symptoms of the common cold or mild pneumonia, depending on the activity of the person’s immune system.
SARS-CoV and MERS-CoV types:
These types are associated with serious respiratory infections, in which it is normally necessary for the person to be hospitalized for monitoring and thus prevent complications. These viruses are transmitted from animals to people and, for this reason, end up triggering a more serious immune and inflammatory response, resulting in more complicated complications and symptoms.
Also, the severity of infection by these viruses may be related to the person’s immune system, since it is more common to arise in people who have the compromised immune system, due to diseases such as HIV or cancer treatment, for example, mainly in the case of the MERS-CoV virus. The first case of MERS-CoV infection was in Saudi Arabia in 2012, however, the virus was easily transmitted to other countries in the Middle East.
The first described case of SARS-CoV infection was in 2002 in Asia and the virus was then associated with a severe respiratory infection, due to the fact that it could spread rapidly among the population through the small drops released into the air through the cough and sneeze of infected people.