Childhood Rashes & DNA Virus Infection
Viral Infectious Disease Chickenpox, Erythemia infectiosum & Roseola
A viral or bacterial infection that causes the skin to erupt in a rash covering most of the body is called an exanthem. Initially six distinct childhood exanthems were identified from what was once called the “measles.” Today, there are many recognized exanthems.
This article series covers some of the virus mediated rashes most commonly encountered during childhood; those caused by DNA viruses (chickenpox, erythemia infectiosum, roseola) and those caused by RNA viruses (rubella and rubeola), as well as transmission and immunization.
DNA Viruses that Cause Childhood Infectious Rashes
Chickenpox
Infectious Agent
Chickenpox is caused by the Varicella zoster virus (VZV) of the Herpesviridae family. This enveloped DNA human herpes virus (HHV-3) is one of the eight herpes viruses known to affect humans.
Symptoms and Course
This virus causes hundreds of itchy, fluid-filled blisters that burst & form crusts. Pox appear 10 to 21 days after exposure. Those infected are contagious one to two days before pox appear and remain contagious as long as uncrusted blisters present.
At Risk
Chickenpox usually occurs in children under ten years old. When adults and older children contract this disease, they usually get sicker than younger children do.
Re-emergence
After initial infection, this virus remains in the body for life, usually kept in check by immune system. However, some infected adults will experience shingles, a painful skin rash that is the result of the Varicella zoster virus re-emerging during periods of stress, when the human immune system is compromised.
Erythemia Infectiosum
Infectious Agent
Also called Fifth Disease and Slapped Cheek syndrome, erythemia infectiosum is caused by human parvovirus B19 (PV-B19). This nonenveloped DNA virus is of the Parvoviridae family, a group of some of the smallest viruses known (Parvus = Latin for small.)
Many types of mammals have strain of parvovirus associated with them, each parvoviruses specific to the taxon of animal they will infect. For example, all strains of canine parvovirus will affect dogs, wolves, and foxes, but only some of them will infect cats.
Symptoms and Course
Bright red cheeks are a defining symptom of the infection in children. A lacy rash may also develop on the rest of the body. This rash can last a couple of weeks (some cases lasting for several months) and may itch. Patients are usually no longer infectious once the rash has appeared.
The disease is usually mild. Teenagers and adults may present with a self-limited arthritis. In certain groups, erythemis infectiosum can have serious consequences, such as infection in 1st trimester of pregnancy potentially causing spontaneous abortion.
Roseola
Infectious Agent
Roseola is caused by two enveloped DNA human herpesviruses, HHV-6 and HHV-7 of the Herpesviridae family. These viruses are also called Roseolovirus.
There are several common names for this infectious disease, including exanthem subitum (meaning sudden rash), roseola infantum (or rose rash of infants), sixth disease (as the sixth rash-causing childhood disease), baby measles, three day fever.
Symptoms and Course
Roseola’s incubation period is 5 to 15 days. Then symptoms begin with a sudden, high fever.
Between the second and fourth day of illness, the fever falls dramatically, and a rash appears on the trunk, spreading to the limbs, neck, and face. The body rash may last a few hours to a few days.
At Risk
This acute disease occurs primarily in infants and very young children. There is no vaccine against rosella, since most children with the disease are not seriously ill. A child with fever should be given plenty of fluids and medication to control the high fever.
This article is for informational purposes only and is not meant to be used for the diagnosis or treatment of infectious disease. If you or your loved ones are sick, please see a doctor, not a computer.
Sources
The Immunization Schedule page of the CDC's website provides many printable files of child and adults immunization schedules.
National Library of Medicine, Medline Plus
Bauman, R. (2005) Microbiology. Pearson Banjamin Cummings.
Park Talaro, K. (2008) Foundations in Microbiology. McGraw-Hill.
