Symptoms | Rabies

Symptoms

Rabies is an inflammation of the brain (encephalitis) with the three most important symptoms (symptom triad) excitement, cramps and paralysis.

  • Prodromal stage (melancholic stage): This stage is of varying length and is characterized by pain at the wound, an unspecific feeling of illness, a slight increase in temperature, headaches, nausea, depressed mood and changes in character such as nervousness.
  • Excitation stage: Pain and disturbing sensations such as tingling (paresthesia) in the area of the wound develop, as well as breathing problems, high fever, anxiety, confusion and mental excitability, which leads to tantrums even on the slightest occasion. In addition, there is increased salivation and tears, whereby the saliva can no longer be swallowed properly due to paralysis of the throat muscles and therefore runs out of the mouth.

    The sight of liquid triggers violent pharyngeal muscle cramps, which is known as an aversion to drinking (hydrophobia). The hydrophobia and the difficulty in swallowing prevent the virus from diluting, which increases the toxic effect of the virus.

  • Paralytic stage: After 1-3 days there is a decrease in excitability and progressive paralysis of the muscles (motor) and senses of touch (sensitive). Death comes from central respiratory paralysis and circulatory failure.

    At this stage the fatal outcome is unstoppable.

The diagnosis of rabies is difficult with initially unspecific symptoms. Initially, the suspicion of rabies is based on observation of the symptoms and questioning the patient according to his or her medical history (anamnesis). The DNA of the rabies virus can be detected in saliva, cornea of the eye and cerebrospinal fluid (liquor cerebrospinalis) by means of polymerase chain reaction (PCR), a method for amplifying DNA.

However, pathogen and antibody detection is only of limited use, since negative pathogen detection does not rule out rabies and antibodies can only be detected in blood and cerebrospinal fluid with a delay of about 7 to 10 days. In the tissue of the brain, the already mentioned negri-bodies can be found after death. There is no specific therapy, only the symptoms can be treated (symptomatic therapy).

The bite wound must first be rinsed extensively with water and cleaned with soap. Then it is disinfected as usual and must be kept open. It may be necessary to surgically remove tissue from the wound (excision).

Furthermore, intensive care measures can help the patient in the final stage of the disease. For this purpose, the patient is admitted to the intensive care unit, where the vital signs are monitored, the patient is made calm and sleepy with medication, and lastly ventilation is provided. If there is a justified suspicion of rabies, a simultaneous vaccination must be carried out immediately, which means that the patient receives rabies antibodies (passive vaccination) and the rabies vaccine (active vaccination) at the same time.

About half of the rabies antibodies should be injected around the wound so that the viruses remaining in the tissue are directly neutralized. However, the vaccination is only effective during the early stage, the prodromal stage. In addition, the tetanus protection must be controlled.

It is also possible, after contact with the pathogen, to take a measure to protect the body and thus escape the outbreak of the disease. People at high risk are vaccinated against rabies. The HDC (human diploid cell) vaccine contains inactivated rabies viruses that can no longer cause the disease.

The viruses are cultivated in human cells or in chicken cells. After the injection, the body then forms antibodies against the viruses. This active vaccination is relatively painless and is administered in several doses into the arm at intervals of a few days or a week.

The exact vaccination schedule depends on the preparation and is specified by the manufacturer.Usually this includes 3 doses on days 0, 7, 21 or 28. The vaccination must be repeated after one year and then every 3-5 years. Only in 30 to 40% of infected people the disease breaks out, which then always ends fatally without treatment. In most cases death occurs by respiratory arrest. However, if the simultaneous vaccination is administered in time and according to the regulations, the probability of contracting rabies is very low.