Diagnosis of influenza

The diagnosis of influenza is usually based on the symptoms of the affected patient. For this purpose, a detailed doctor-patient consultation (anamnesis) is of primary importance. During this conversation, the doctor asks the patient about possible previous illnesses and the type and extent of the current symptoms.

In addition, allergies, regularly taken medications and different life habits play a decisive role in this conversation. In a second step, the physician obtains an initial overview of the patient’s condition (general condition). This is done by carrying out a comprehensive physical examination.

The doctor checks all organ systems relevant for influenza: In this way, the suspected diagnosis “flu” can be confirmed in most cases. In addition, a nasal swab is usually taken from the back of the nasal cavity. Alternatively, a deep throat swab can also be taken.

The tracheal secretion (secretion from the trachea) or secretions of the bronchial system can also be used to detect the influenza virus.

Auscultation (listening) of the lungs and heart
Palpation of the abdomen.

In addition, many physicians rely on the collection of patient blood to diagnose influenza. In a special laboratory, the submitted material is examined in various ways for the influenza virus or metabolic products of the pathogen.

The most important method for detecting the influenza virus is the so-called influenza PCR (polymerase chain reaction), in which the genome of the pathogen is amplified and then assigned to the influenza virus. In addition, in many cases pathogens can be directly detected by electron microscopy or cell culture. From the second week after the outbreak of influenza, influenza-specific antibodies can also be detected in the blood.

At the beginning of the disease phase, the affected organism usually does not have enough antibodies to guarantee a proper detection. This is the reason for the delayed significance of the antibody test. Furthermore, other parameters measurable in the blood also indicate a viral infection.

As a rule, the so-called blood sedimentation rate is significantly increased in the presence of a viral infection such as influenza. A measurement of the white blood cells (if leukocytosis is suspected), on the other hand, is of little significance, as they can behave quite variably in the presence of viral infections. Both an increase and a decrease in white blood cells is possible.

In the meantime, there are various rapid tests that can diagnose influenza within a few minutes. These rapid tests have color-coded antibodies that react to different proteins of the influenza virus. In this way, metabolic products of the influenza virus can be displayed in color.

A result of these tests can be read after about 15 minutes. The therapy in the presence of a real influenza can be carried out in two different ways. On the one hand, the focus is on alleviating the symptoms, but in individual cases it may also be necessary to combat the causative pathogen directly.

1 Antiviral therapy A number of antiviral drugs are now available to treat influenza. If taken early, the duration of the illness can be significantly reduced. In addition, it has been shown that patients who receive antiviral treatment for influenza at an early stage are significantly less likely to develop life-threatening complications.In general, two different classes of substances are used to treat influenza.

In addition to inhibitors of a specific membrane protein (M2), which acts as a proton pump on the viral envelope, the so-called neuraminidase inhibitors in particular are frequently used today. By taking neuraminidase inhibitors, the activity of the viral surface enzyme neuraminidase is throttled, thus blocking the release of the virus when it is released from a host cell. Neuraminidase inhibitors thus prevent the infection of other, previously uninvolved cells.

It should be noted, however, that both substance classes only prevent the flu virus from multiplying. Viruses already present within the organism cannot be inactivated or eliminated by these drugs. For this reason, the time at which the antiviral drugs are taken has a decisive influence on the success of the treatment.

Experts consider flu treatment with antiviral drugs to be appropriate only if the first symptoms do not appear more than 48 hours after the start of treatment. Otherwise, there is no positive effect on the course of the disease even if the drugs are taken. 2 Symptomatic therapy Since an immunocompetent organism is in most cases able to cope with an infection with the flu virus itself, the symptomatic therapy is in the foreground in many cases.

The aim of this treatment strategy is to relieve the typical symptoms of influenza and to increase the well-being of the affected patient. In cases of high fever and for headache, muscle pain and pain in the limbs, drugs such as Ibuprofen® or Paracetamol® can be taken. Both drugs have both analgesic and antipyretic effects.

For this reason they are particularly suitable for the symptomatic treatment of influenza. If necessary, one tablet can be taken about every 5-6 hours. In many cases it has also been shown that the alternation between ibuprofen and paracetamol leads to an improved antipyretic effect of the preparations.

This means, for example, that affected patients start taking one tablet of ibuprofen if necessary and then take a dose of paracetamol five to six hours later. Painkillers such as Aspirin® (acetylsalicylic acid; ASA) should never be used in children under 12 years of age. Taking Aspirin® in the presence of a viral infection can lead to dangerous and 25% fatal Reye’s syndrome in children under 12 years of age.

In addition, affected patients should drink enough fluids during the disease phase and stay in bed if possible. The body needs sufficient rest to contain the virus and to promote recovery. 3 Other treatment options Although influenza is an infectious disease caused by a virus, the use of an antibiotic may also be useful. The reason for this is that infection with the influenza virus weakens the immune system to such an extent that it can occur frequently at the same time.

Bacterial throat infections
Acute bronchitis
Pneumonia or
Meningitis