Chickenpox: Overview, Causes, and Symptoms
The varicella zoster virus causes chickenpox. You can get more information on symptoms, infection and treatment of the chickenpox disease here…
Chickenpox: In brief
Typical of chickenpox is the rash, in which red spots, blisters and already scabbed areas appear next to each other – the so-called “starry sky”. Chickenpox during pregnancy is dangerous for the baby. The virus is highly contagious and can be transmitted to others one or two days before the rash appears. About a week after the start of the rash, the blisters are scabbed and visits to communal facilities are allowed again. A vaccination can protect against the disease.
What is chickenpox?
Chickenpox (varicella) is a highly contagious viral disease. The most important symptoms are a rash with red spots and blisters all over the body and a slight fever. Rare but possible complications include pneumonia or meningitis and bacterial infection of the blisters. Years later, shingles can occur due to viruses remaining in the body. Since the vaccination was recommended in 2004, the disease has become much rarer.
Causes and infection
The varicella zoster virus (VZV) is the causative agent of chickenpox. It belongs to the herpes viruses and is so contagious that most people were infected with the pathogen as children before the introduction of vaccination. Anyone who has been infected once is usually protected against the virus for the rest of their lives. For this reason, chickenpox was counted among the children’s diseases. However, adults who have not had chickenpox or have not been vaccinated against it can get the disease.
It is transmitted through the air (the “wind”) by droplet nuclei containing the virus, which are excreted by sick people when breathing and coughing and can cause people within a radius of several metres to become infected. The content of the blisters appearing on the skin is also infectious.
The disease is already contagious one or two days before the rash appears. The risk of further spread is greatest in the following two to three days, while new blisters are constantly appearing. A good five days after the last episode, when the blisters are completely scabbed, the patient is no longer at risk of infection. Only then – about a week after the onset of the disease – are they allowed to return to community facilities such as schools and kindergartens in accordance with the Infection Protection Act. A written certificate is not required.
Shingles can only be infected with chickenpox via the contents of the blisters. This means that it is usually sufficient to cover affected areas with clothing.
Symptoms
The incubation period is between eight days and three weeks. Usually the typical skin rash appears about 14 to 16 days after infection. Sometimes it is preceded by an indeterminate feeling of illness with headache, loss of appetite and slight fever, but often this is not noticed at all.
Suddenly red spots and itchy blisters appear. If one could think of mosquito bites at first, the rash spreads to areas of the body that are actually covered by clothing, making the diagnosis easier. The blisters can also appear under the eyelids, on the mucous membrane of the mouth, the hairy head and the genitals. Since red spots, blisters and already opened vesicles are usually visible at the same time, one also speaks of a “starry sky” image. Usually there is only a slight fever.
Complications
Bacteria such as staphylococci and streptococci are always present on our skin without being noticed. If the blisters are opened, these can lead to infections, so that a therapy with antibiotics may be necessary. If the patient scratches the blisters, scars can form later.
Pneumonia caused by the chickenpox virus cannot be treated directly. It occurs about three to five days after the onset of the disease and is much more common in adults than in children. Inflammation of the cerebellum (cerebellitis), which usually manifests itself with balance problems, can also occur acutely, but also not until three weeks later. Very rare are inflammation of the brain (encephalitis) or changes in the blood vessels, up to and including a stroke in children. In individual cases, complications such as inflammation of the heart muscle, changes to the cornea of the eye, inflammation of the kidneys, inflammation of the joints, tendency to bleed and inflammation of the liver can also occur.
Chickenpox during pregnancy
During pregnancy chickenpox is a danger for the unborn child. If an expectant mother falls ill with it before the 20th week of pregnancy, there is a risk of damage to the child of one percent. It can lead to brain damage, limb malformations, growth disorders or a congenital cataract.
If the mother is infected five days before or two days after the birth date, the risk of the child becoming ill is particularly high. Special treatment measures are necessary for the so-called newborn varicella. The course of the disease is particularly severe with such small babies and the risk of the child dying of the disease is about 20 percent.
Women who wish to have children and who have not been vaccinated against chickenpox should therefore be vaccinated at least four weeks before trying to become pregnant. This is because you should not be actively vaccinated against chickenpox during pregnancy. However, after contact with chickenpox, the administration of antibodies against the virus is possible. Pregnant women who have come into contact with varicella should therefore contact their gynaecologist as soon as possible.
Diagnosis
The doctor can usually recognise a chickenpox disease simply by the appearance of the rash and how it spreads over the body. Antibodies against the varicella zoster virus (VZV) can later be detected in the blood.
It is also possible to detect the viruses directly from the vesicle secretion. This is done using the polymerase chain reaction (PCR) method. For this, the genetic material DNA is amplified in the test tube. This method allows the rapid detection of chickenpox viruses, but is only indicated in isolated cases. It can be important, for example, in the case of an expectant mother if the birth has to be artificially delayed for a few days because of chickenpox or if a special therapy has to be initiated.
Treatment
In the normal course of the disease, the main aim is to relieve the itching. If the patient scratches open the blisters, infections occur more easily and scars remain. For a long time, a zinc shaking mixture for dabbing on chickenpox has proven to be effective, it helps the blisters to dry out. The fingernails of the sick child should be cut short. Medicines against itching, so-called antihistamines, as known from allergy treatments, are available in drop form, for example. If necessary, have your doctor recommend a suitable preparation and make sure that you take the correct dosage!
In case of fever or pain, drugs with the active ingredients paracetamol or ibuprofen in a dosage suitable for the child’s weight can help. If in doubt, talk to your doctor or pharmacist about which medicine is suitable for your child.
If a baby falls ill shortly before or after birth, there is an urgent need for treatment. Before the birth, the expectant mother receives special immunoglobulins within one to three days after the possible infection. These are ready-to-use antibodies against the varicella zoster viruses. After birth, the antibodies are injected into the baby. In addition, the baby is usually given a virus-inhibiting drug (active ingredient: Aciclovir), especially if the baby already shows symptoms of the disease.
The preventive administration of antibodies against the virus after contact with a sick person can also be useful for patients with a weakened immune system, such as cancer patients or patients with immune defects.
Vaccination
Without an effective vaccination, varicella zoster viruses cause almost 43,000 complications every year, about 5700 of the patients have to be treated in hospital and 25 to 40 die. Therefore, according to the 2004 STIKO recommendation, all babies aged between 11 and 14 months and between 15 and 23 months should be vaccinated not only against measles, mumps and rubella (MMR) but also against chickenpox. This is also possible with a quadruple vaccination: the MMRV vaccination. The minimum interval between the two vaccinations is four to six weeks. Older children and young people should also receive two vaccinations up to their 18th birthday if they have not yet contracted chickenpox. This also applies to adults who have not yet been immunised and who are particularly at risk, such as women who wish to have children and people with an immune deficiency or severe neurodermatitis.
Shingles: reactivation of the chickenpox virus
The varicella zoster viruses are only suppressed by the immune system and usually not completely eliminated. They then migrate from the skin via the sensitive nerve tracts into the nerve cells (spinal ganglia) along the spinal column and hide here without causing further damage. If the strength of the immune system decreases, for example in stressful situations or due to illness, the risk increases that the viruses become active again and then cause shingles.
Shingles or herpes zoster manifests itself with vesicles similar to chickenpox. However, these only develop on the part of the skin surface that is supplied by the nerve tract in whose spinal ganglia the viruses are located. This is usually on the trunk. Sometimes the trigeminal nerve is also affected, then the rash forms on the face and is called facial erysipelas. The rash, which is arranged like half a “belt”, is often accompanied by severe pain, which can sometimes persist as nerve pain even longer after the disease has been overcome.
Important notice: This article contains only general information and must not be used for self-diagnosis or self-treatment. It cannot replace a visit to the doctor. Unfortunately, it is not possible for our experts to answer individual questions.
We also recommend you to read our article on shingles.