Covid-19

Cause

Covid-19 is believed to be a zoonosis. That means it's transferable from vertebrates to humans. The coronavirus has most likely been spread from an exotic animal in China to humans.
Between people, disease transmission occurs because the virus spreads from the mouth and pharynx of an infected person through mucus in fluid droplets in the air by, among other things, sneezing and coughing. By touching the face with hands, it is possible to contaminate each other by mutual contact, and possibly also through contaminated surfaces. Fecal contamination is uncertain.
The coronavirus has multiple variants. The incubation period is two to fourteen days, but in most cases three to six days. The disease is highly contagious.

Symptoms

The disease is characterized by flu-like symptoms, including fever, cough, shortness of breath, muscle pain and fatigue. Loss of smell and taste may also occur. The disease affects the lungs. In severe cases, it leads to viral pneumonia, acute respiratory distress syndrome (ARDS), sepsis, kidney failure and septic shock that may be fatal.
The majority of patients have no, mild or moderate symptoms, develop antibodies between six to twelve days and then become more resistant to the virus (immune) for a period of time. Fewer antibodies may be produced in case of mild symptoms. Mild symptoms include a sore throat, mild cough and an increase in body temperature to 38.0 °C.

Diagnosis

The diagnosis of Covid-19 is based of the following tests:

• PCR-test (Polymerase chain reaction test). The standard diagnostic method by means of a reverse PCR-test (rRT-PCR) on a sputum sample or a nasopharyngeal swab.
• Antibody test. An antibody prevents the virus from infecting a person. An antibody against SARS-CoV-2 has been discovered that can help detect and prevent Covid-19.
• Radiology. In an X-ray examination, a normal image may be indicative of suspicion of pneumonia. In the case of a proven Covid-19 infection, a CT scan is often performed, as it may detect changes before they are visible on a normal image. Characteristic are opaque changes of the lung parenchym that resemble milk glass.

Treatment

As yet, there is no proven cure for the disease, therefore patients are placed in (home) isolation. However, the symptoms can be reduced, so that the immune system gains time to fight the virus.
In the case of serious infections, the following drugs may be administered to patients: Paxlovid, Remdesivir, Dexamethason and monoclonal antibodies. In very seriously ill patients, complications of the disease may occur, such as a bacterial superinfection. These patients are given antibiotics. Some of the patients need extra oxygen through ventilation.
Since the end of 2020, a vaccine for the SARS-CoV-2 virus is available.

Prognosis

Four out of five people who contract Covid-19 have a mild course and the disease cures in about two weeks. People with serious symptoms generally need more time to recover (three to six weeks).
Potential risk factors for a poor prognosis include higher age, high SOFA score and a d-dimer amount greater than 1 μg/ml. Among those who died from Covid-19, many had pre-existing conditions, including diabetes, hypertension and cardiovascular disease. The average time of initial symptoms to death was fourteen days.
Some people have long-term symptoms after an infection with SARS-CoV-2. This is called 'Long Covid' or 'PASC' (Post-Acute Sequelae or SARS-CoV-2 Infection). These symptoms can last up to a few weeks and sometimes even several months or years after infection with the coronavirus.

Considerations

The main measures that can be taken to prevent spread of the coronavirus:

• Wash hands regularly with soap and water.
• Cough and sneeze inside the elbow.
• Use paper handkerchiefs.
• Don’t shake hands.
• Stay at home if you have a cold.
• Social distancing: keep sufficient distance from each other (minimal 1.5 meters or two arm lengths).
• Use face masks.
• Ventilate rooms.

Most of these measures apply to all viruses that may cause flu and colds, so it’s always important to follow these.

Facts

• The outbreak of the new coronavirus started in December 2019 in the Wuhan region of China.
• The coronavirus is a common cold virus. But there are special forms of that virus. For example, SARS and MERS are both diseases caused by a coronavirus. Covid-19 can now be added to that list too.
• There are some cases worldwide of pets infected with the new coronavirus, including cats and dogs.