Erythema infectiosum (synonym: ringworm, E. infantum febrile, E. infectiosum, exanthema variegatum, megalerythema infectiosum, 5th disease) is an infectious disease.
Occurrence: The infection occurs worldwide.
The contagiousness (infectiousness or transmissibility of the pathogen) is very high, but not as highly contagious as measles or varicella (chickenpox). It exists even before clinical symptoms appear!
Ringworm viruses are resistant to most disinfectants (resistant).
Epidemiologically, endemic cycles are observed every 3-4 years. The disease occurs more frequently in spring and winter.
Transmission of the pathogen (route of infection) is aerogenic (droplet infection in the air) or by smear infection or contact with body fluids such as saliva or blood.Parvovirus B19 can also be transmitted with breast milk.
The incubation period (time from infection to onset of disease) is usually 6-18 days.
Peak incidence: The disease occurs predominantly in young children and schoolchildren, between 6 and 15 years of age. Up to 50% of children and adolescents have antibodies to human parvovirus B19 (in their blood). In the elderly, the rate of contamination rises to 80%.
Seroprevalence (percentage of patients tested serologically positive) is approximately 40-60% depending on age; 95% in those over 75 years of age. Women of childbearing age have a seroprevalence of 69-72%.
Cause
Transmission is from person to person by droplet infection-for example, sneezing-that is, via nasal and pharyngeal secretions. The causative agent is parvovirus B19.
Symptoms – Complaints
The following symptoms may indicate a ringworm infection:
- Mild fever
- Headache
- Itchy rash
Special features during pregnancy
During pregnancy, the virus can be transmitted to the unborn child through the placenta (placenta).consequences of infection for the unborn child are:
- Severe anemia (anemia)
- Hydrops fetalis – accumulation of water in fetal tissues.
- Amniotic death
Note!The majority, or 60% of infections, progress without signs of illness in the mother.
Diagnostics
The diagnosis of ringworm is made by blood testing (serology).
In case of suspected infection or contact with an infected child, a blood test should be performed immediately. This is necessary to clarify the initial immunologic situation, i.e., whether an infection already existed in the past and thus immune protection exists so that the unborn child cannot become ill, or whether a fresh infection or no infection is present.Laboratory parameters 1st order – obligatory laboratory examinations.
- Parvovirus B-19 lgG antibody.
- Parvovirus B-19 lgM antibody
If IgG antibodies are detectable, but no IgM antibodies, then there is immune protection!IgM antibodies are detectable 7-10 days after infection and remain positive for up to 3 months.
Caution!If there is no immune protection, repeat blood testing after 2 weeks is essential to rule out possible infection.
Benefits
The detection of an initial infection with ringworm during pregnancy, allows targeted surveillance ultrasound diagnosis, so that in the event of hydrops fetalis – water accumulation in the fetal tissues – early blood exchange can be performed in the child.
