Coronavirus or CoV is the name of a type of virus wrapped in the coronavirid family. Coronaviruses have a viral envelope with a positive RNA genome and an incredibly large kilobases capsid for an RNA virus. The crown virus takes its name from the appearance of virions under an electron microscope, with a fringe of large bulbous projections that resemble the solar corona. Coronaviruses rank among Nidovirales, since all viruses of this order produce a nested interlocking interlocking set of sub genomic mRNs during infection. Peak-shaped proteins, envelopes, membranes and capsids contribute to the overall structure of all coronaviruses.

Coronaviruses were discovered in the 1960s. The first discoveries were those of infectious chicken bronchitis, then two viruses from the nasal cavities of human patients with colds, later called human coronavirus 229E and human coronavirus OC43. Seven types of coronavirus commonly infect humans, four of which are non-serious and three causing serious infections. Benign infections are colds with fever and sore throats due to swollen adenoid vegetation, mainly in winter and early spring. Severe infections are caused by coronaviruses that are not found naturally in humans but are usually found in mammals such as bats.

The first serious infection in 2003 triggered a global alert by WHO. The name of the disease is severe acute respiratory syndrome associated with coronavirus. This epidemic began in China. The beginning of this epidemic is the consumption of a wild animal in a Chinese restaurant: the masked palm civet. This disease, which killed about 10% of people with the disease, or 774, is considered eradicated. The second in 2012. It began in Saudi Arabia and was named Middle East Respiratory Syndrome. This disease was triggered by the consumption of camel milk and by the proximity to camels. Its mortality rate was 35%. Only 449 people died as a result of the infection due to the small number of people infected. This disease still exists because in order to eradicate it, people who traditionally use camels would have to be able to do without it. The last one in 2019. It is the disease known as coronavirus disease 2019 or Covid-19 in short. The origin of the disease is not certain although it is thought that the consumption of pangolin meat may be the cause.

Depending on the virus involved, the severe forms of the disease have their peculiarities. For example diarrhea was very common in SARS but rare in coronavirus disease 2019. Transmission and contagiousness also vary depending on the coronavirus, and perhaps its strain within an epidemic. Early data on COVID-19 shows that its virus is transmitted by contact with respiratory droplets. An epidemic requires an infected person to infect on average more than one. Prophylaxis requires primary prevention to adopt and adopt behaviours that defy the transmission of the virus.

The main recommendations are: Wash your hands frequently with soap or alcohol-based disinfectant, effectively destroying the coronaviruses on the hands. Avoid touching your face, eyes, nose and mouth as hands touch many potentially virus-carrying surfaces. Once infected, the hands can transmit the virus to the eyes, nose or mouth; from there, the virus can enter the body and trigger the disease. Do not come into contact with obviously sick animals, do not consume meat from sick animals, and do not consume undercooked animal products or raw vegetables if they have not been washed with uncontaminated water.

Like all viruses, coronavirus is insensitive to antibiotics and bacteriophagic preparations; these can only be useful against bacterial over infections, which are secondary to the disease. Since March 2, 2020, the Chinese authorities have been working in partnership with Gilead Sciences on a treatment trial for infected patients, the results of which are not yet known. In terms of vaccines, the rapid eradication of the previous SARS epidemic has not given way to clinical trials. Inactivated virus vaccines, and others based on S and N proteins, have been under study for several years.