Infectious erythema is a disease caused by parvovirus B19 infection. Usually it concerns several-year-old children. The characteristic symptoms are a garland-like rash and a butterfly-shaped erythema on the face. This symptom usually lasts about 11 days and resolves without peeling. Children with a rash are generally not contagious.

Infectious erythema

Infectious erythema is one of the common rash diseases in children, characteristic of preschool and early school age. The infection is transmitted from person to person via droplets and sometimes also via infected blood or plasma preparations. The source of the parvovirus infection is a sick child or a carrier that does not show any symptoms of the disease. Vaccine against infectious erythema does not exist, although it is not necessary, as erythema is generally mild (50% asymptomatic). The disease resolves spontaneously, thus giving life-long immunity.

The hatching period of the infectious erythemais approx. 14 days.

Infectious:Slight, most often children with a rash are not contagious.

Characteristics of the parvovirus B19

Parvovirus B19is responsible for the formation of infectious erythema. It belongs to the group of DNA-viruses, which means that its genetic data is transmitted by deoxyribonucleic acid. Parvovirus B19 is transmitted by airborne droplets and blood and is difficult to destroy with chemical and physical agents. In larger groups of people, this virus can cause an epidemic, but infection does not always lead to symptoms such as rashes or other symptoms. According to many studies, most people have been exposed to parvovirus B19 at least once in their life because it has specific antibodies.

Other forms of parvoviral infection

Infectious erythema is actually one form of parvovirus B19 infection.There are also other ailments caused by this microorganism:

1. haemolytic crisis – this is an ailment, or rather a series of symptoms, occurring as a result of a sudden breakdown of red blood cells; the consequence of the disease is enlarged spleen, changes in the bone marrow and anemia with jaundice;
2. parvoviral arthritis – is a condition that usually affects adults, mostly women; the characteristic symptom is pain and swelling in the joints (usually the hands);
3. fetal death– Parvovirus B19 infection is particularly dangerous in pregnant women as it may result in serious complications of the fetus and even lead to its death;
4. anemiaandneuropathy– is characterized by low levels of red and white blood cells, which results from bone marrow disorders due to viral infection; abnormalities arise after exposure to parvovirus B19 in immunocompromised patients.

Infectious erythema – symptoms

Infection with parvovirus B19 does not mean that we will immediately develop a rash. Outbreaks can occur in large clusters of children, such as schools and kindergartens. Infectious erythema is more common in younger children, and the first symptoms appear about two weeks after infection.

There are usually no prodromal symptoms. The course is fever-free or with a slightfever, sore throat, runny nose and sometimes muscle pains. These symptoms are flu-like and appear before the characteristic rash. Of course, not all symptoms can appear simultaneously, and in addition, none of them is alarming or specific, so making an accurate diagnosis is not easy.

Very often, the only symptom of infectious erythema is arashwith a characteristic garland-like appearance. Initially, a vivid erythema appears on the face, mostly in the cheeks, leaving a pale around the mouth, then the arms, torso and limbs are affected. The spots turn pale in the central part, creating erythematous rings, which creates its characteristic appearance. It is worth noting that the rash does not extend to the palms and soles of the feet.

The duration of the rash varies, usually 11 days. It is oftenitchyand passes without peeling. Periodically, it may renew itself in a warm bath, after exercise, rubbing the skin, or with violent emotions.

Important:A parvovirus B19 infection does not mean that you will get symptoms 100 percent. Disease epidemics usually occur in nurseries and kindergartens.

Infectious erythema diagnosis

When suspecting infectious erythema, it is important to consult a doctor and differentiate the disease with other ailments. The rash characteristic of an infectious erythema can also be associated with other conditions. The doctor assesses the skin changes – their appearance and location.

Serological tests areneeded to confirm the suspicions about the presence of infectious erythema . They are aimed at detecting antibodies that are created by the human body as a defense against infection. Antibodies are attached to the virus, thereby destroying it. For this reason, IgM antibodies are usually measured in the patient’s serum, high levels of which suggest a recent infection. On the other hand, IgG antibodies indicate a past infection, i.e. the development of immunity. In any case, virus contact is necessary to build up immunity.

Another diagnostic method isthe direct determination of the genetic material in the patient’s blood serum. It is performed in those people who cannot be diagnosed solely on the basis of serological tests, i.e. patients with ailments that disturb the functioning of the immune system. Serological testing may be negative in these patients, which does not mean that they are not infected. Therefore, the above study is carried out for confirmation.

In addition to the above-mentioned methods,classical laboratory testsin the form of peripheral blood counts are also performed. In the patients in the study, low blood protein levels are observed with a simultaneous increase in lymphocytes (relative lymphocytosis). In addition, hemolytic anemia is diagnosed. In pregnant women, ultrasound is an auxiliary examination.

Infectious erythema and pregnancy

Infection in pregnancy is dangerous, especially in the first trimester. At this stage, it may pose a risk to the developing inside the fetus. Therefore, anyone who develops a rash of infectious erythema should inform any pregnant woman with whom they come into contact within two weeks. Subsequently, each woman expecting a child should notify her attending physician about this contact. He or she will probably order a serological test to determine if the pregnant woman has antibodies against parvovirus B19. After analyzing the test results, the doctor will decide on further treatment.

How to treat infectious erythema?

It is impossible to cure the causes of infectious erythema, and prescribing antiallergic preparations and antibiotics will not bring any effect. In patients with a normal immune system, the disease is eliminated on its own. Radical treatment is implemented in immunocompromised patients. It is very rare for children to need antibodies to stimulate their immune system to fight the infection. On the other hand, people suffering from immune deficiencies have been a source of infection for the environment for much longer than people without this defect. The indications for hospitalization are situations in which anemia or infection of the fetus has occurred.

Attention!The sick person is most contagious before the onset of the rash!

In people with normal immunity, the prognosis of the disease is generally good. After the rash has cleared, you can return to your normal lifestyle.

Infectious erythema – complications

The most common complication of infectious erythema is:

1. arthritis (most often of the knees, hands and wrists),
2. anemia (due to a reduction in the production of red blood cells).

People who have previously struggled with anemia or have a lowered immune system should be under constant medical supervision.