SARS

SARS: description

SARS is the abbreviation for “severe acute respiratory syndrome” – in English “severe acute respiratory syndrome”. The name already describes some of the complaints that patients with SARS have: “Respiratory” means that the disease affects the respiratory system.

A new disease

In November 2002, SARS was first reported. It initially appeared only in Southeast Asia. Within six months, the disease had spread worldwide. In total, about 8,000 people fell ill with SARS, 744 of whom died from the disease.

Mainly adults were affected by SARS. Until that time, viruses that belonged to the same group as the SARS virus (coronavirus) were known only as causative agents of mostly harmless colds in adults.

Since 2003, only a few cases of SARS have occurred that originated in research laboratories conducting research on the virus.

Similar diseases

In 2012, another coronavirus was discovered. Especially in the Arabian Peninsula, people were infected who subsequently suffered from respiratory complaints and kidney failure. About half of them died. The virus that was detected there is called MERS-CoV (middle east respiratory syndrome coronavirus).

SARS: symptoms

The time between infection and the onset of SARS disease (incubation period) is about two to seven days. In the first days of the disease, SARS usually announces itself

• fast rising fever
• a headache
• Muscle aches
• strong general malaise

After about three to seven days begins the phase of the actual SARS, in which especially the respiratory organs are affected (respiratory phase). The patients then suffer from

• dry cough
• Shortness of breath (dyspnoea)
• Lack of oxygen in the blood (hypoxemia) and the organs

About 70 percent of patients additionally suffer from fluid diarrhea. In some of them, this occurs already in the first week of illness.

If the lungs are damaged so severely by the SARS virus that they can no longer provide sufficient gas exchange, this is called lung failure. Without intensive medical help, patients would die. However, numerous cases of SARS have also been reported that were mild or symptomless.

SARS: causes and risk factors

The cause of SARS is infection with the SARS virus. Viruses are particles that consist of an envelope and an inherited genetic material. The SARS virus belongs to the coronaviruses and is correctly called SARS coronavirus. “Corona” is the name of the envelope of this type of virus that looks like a wreath under the microscope.

Animals carry the virus

It is believed that the SARS virus comes from an animal reservoir. This means that originally animals carried the virus in themselves and the viruses could multiply in them. It is believed that Asian bats formed this reservoir. SARS was eventually transmitted to humans via other animals such as cats. This is why we also speak of a zoonosis in connection with SARS. Zoonosis refers to diseases that can be transmitted from animals to humans and vice versa.

This is how the virus damages the body

A human-to-human transmission of SARS takes place as a droplet infection over the air. Only patients who are acutely ill are infectious. The SARS viruses then infect the cells lining the respiratory tract. They are referred to in the bronchi as ciliated epithelium, as they have small, like eyelash-looking formations on their surface (cilia). These cilia are normally used to clean the respiratory tract, for example, by transporting mucus that has formed through a beating movement to the outside.

The viruses multiply in the cells of the ciliated epithelium and paralyze the cilia movements. As a result, the defense against pathogens, pollutants and mucus is inhibited. In addition, in the lungs, the release of carbon dioxide and the uptake of oxygen (gas exchange) can no longer take place properly, as well as the alveoli, in which the gas exchange takes place, are damaged by the virus.

Who is at risk?

Basically, anyone can get infected with SARS that comes in contact with the virus. Observations show that certain groups of people are particularly at risk. During the 2002 and 2003 outbreaks, it was found that children rarely had SARS. Men died more often than women, especially if they were already suffering from other, chronic illnesses.

When pregnant women became infected with SARS, the unborn child died more frequently during the first few months of pregnancy. In the later pregnancy, on the other hand, the mortality of expectant mothers increased.

SARS: examinations and diagnosis

In order to make the diagnosis “SARS”, your doctor first asks you in detail about your medical history. He will ask you the following questions:

• Since when do you feel sick?
• Do you have fever?
• Do you have muscle aches?
• Do you get good air?
• Have you been abroad recently?

Subsequently, your doctor will examine you physically. Your temperature is measured and the lungs are monitored. In addition, an X-ray of the chest can be made. This can detect changes in the first few days of SARS disease.

All results from anamnesis interview and physical examination may also indicate another condition, such as flu. If there is a suspicion that it may be SARS, for example, because a variety of illnesses have occurred again, a blood test is performed. Only then can SARS be established beyond doubt. For this blood is taken from you and examined in a special laboratory under high security conditions. In this case, a method is used with which the genome of the virus can be directly detected.

Other evidence of SARS disease can be obtained by searching for specific antibodies in the patient’s blood. These are formed in the course of the disease by the body to fight the viruses.

SARS: treatment

A causal therapy of SARS does not exist. So there are no drugs that could kill the SARS virus in the human body. Therefore, the treatment is purely symptomatic. So you treat the individual signs of disease such as fever or pain, without remedy the cause.

In the case of SARS, one uses respiratory masks with oxygen to relieve breathlessness, antipyretic agents such as paracetamol or ibuprofen, and infusions to maintain the body’s hydration, especially in cases of severe diarrhea.

Interferon alpha (IFNα) has been found to aid the healing process in SARS. Interferons are proteins that are also formed by the body itself and support the immune system, especially in the fight against viruses.

An important goal of the therapy is to prevent the disease spreading in the population. Therefore, SARS patients are isolated. Care should be taken that persons such as medical personnel approach the patient only with a mask and a protective coat. In addition, hands must be thoroughly disinfected after each contact.

SARS: disease course and prognosis

The time between infection and the onset of SARS disease (incubation period) is about two to seven days. Subsequently, the infection often proceeds in two phases. In the first week mainly flu-like symptoms appear, while in the second week of illness shows the full screen of SARS.

About ten percent of patients die of SARS. It is also reported by mild forms that remain almost asymptomatic. The patients survive one SARSInfection, the disease usually heals without consequences.