Coronaviruses families have been causing problems for humanity for a long time. Several versions are known to trigger common colds and more recently two types have set off outbreaks of deadly illnesses: Severe Acute Respiratory Syndrome (SARS) and Middle East respiratory syndrome (MERS). But their impact has been mild compared with the global havoc unleashed by the novel coronavirus that is causing the Covid-19 pandemic. This novel coronavirus was identified last year in the city of Wuhan, in Hubei Province in China and was named Covid -19. It is an infectious disease caused by a new virus that has not been previously detected in humans. In only a few months Covid-19 has triggered lockdowns in most countries and claimed hundreds of lives and as the disease continues to spread affecting majority of the nations across the world with Nigeria not excluded.
If an individual is been infected by a viral infection, the virus is capable of reproducing thousands of identical copies in the host. COVID-19 is one of the members of the coronaviruses known to infect humans and the third in the past thirty years to be transmitted from animals to humans (zoonotic disease). Coronaviruses are a family of hundreds of viruses that cause respiratory illness (like the flu) with symptoms such as cough, fever, sometimes gastrointestinal discomfort and in more severe cases, difficulty in breathing, pneumonia, kidney failure and even death.
The severity of the infection depends on couple of factors, one is the part of the body the virus attaches, the less serious strains of coronavirus like the ones that causes common cold attaches to the cells in the higher respiratory tract like the nose and throat .The more deadly strains like Covid -19 which can cause kidney failure in addition to respiratory problem and death attaches to the lungs and bronchial tubes.
Another factor that contributes to the severity of infection is the proteins the virus produces. Different genes mean different proteins, more virulent strains such as COVID-19 produce different proteins which can destroy the immune system and when even higher immune system are produced by infected individual’s body they get even more sick.
MODE OF TRANSMISSION
When an infected person sneeze or cough without covering his/her mouth/nose, the droplets from such individual contains the virus which can remain in the air for few minutes thereby transmitting it to healthy individuals around.
Close or personal contact such as touching or handshakes with an infected individual
Touching surfaces with the virus on it and then touching ones mouth, nose and eyes without washing.
“A Covid-19 infection is thought to be generally mild, and that really is the secret of the virus’s success. Many people don’t even notice they have got an infection and so go around their work, homes and supermarkets infecting others.”
By contrast, Sars – which is also caused by a coronavirus – makes patients much sicker and kills about one in 10 of those infected. In most cases, these patients are hospitalized and that stops them infecting others – by cutting the transmission chain.
In other words the ability of a person to be Covid positive and not show symptoms makes it easy for spread unnoticed.
WHY THEN DOES THE VIRUS SOMETIMES CAUSE DEATH?
The virus can cause severe problems in some people. This happens when it moves down the respiratory tract and infects the lungs, which are even richer in cells with Ace-2 receptors. Many of these cells are destroyed, and lungs become congested with bits of broken cell. In these cases, patients will require treatment in intensive care
Even worse, in some cases, a person’s immune system goes into overdrive, attracting cells to the lungs in order to attack the virus, resulting in inflammation. This process can run out of control, more immune cells pour in, and the inflammation gets worse. This is known as a cytokine storm. (In Greek, “cyto” means cell and “kino” means movement.) In some cases, this can kill the patient.
Just why cytokine storms occur in some patients but not in the vast majority is unclear. One possibility is that some people have versions of Ace-2 receptors that are slightly more vulnerable to attacks from the coronavirus than are those of most people.
SYMPTOMS OF COVID-19
The incubation period is between 2-14 days In order words that is how long it may take the virus to show noticeable symptoms in any infected individual.
Some individuals will not show any symptoms.
The symptoms of Corona Virus include but not limited to:
Running nose, chest pain, Continuous cough, Chills, , Headache , Fever, Feeling of being unwell, loss of appetite, loss of smell, diarrhea, Shortness of breath ,difficulty in breathing, rapid heartbeat, Pneumonia, etc
People with underlying medical disease such as high blood pressure, heart diseases or diabetes, or chronic respiratory conditions, tthose with other infectious disease such as HIV/AIDS,and immuno suppression state, and the elderly are at a greater risk of serious illness from Covid-19…………………………………..…
References/Credit: World Health Organization, Guardian.com(uk),NCDC.