slap cheek disease

HEALTH & FITNESS

Slapped cheek disease or fifth disease is also medically referred to as erythema infectiosum. It is an infection caused by the parvovirus B19 virus. It most commonly occurs in children aged 4-12 years, but anyone can be affected. It is infectious, which means it can be passed on from one person to another. The infectious period is for 4-20 days before the rash appears. By the time the rash develops, it is usually no longer infectious.

A number of individuals have had this infection in the past, usually without realising it. One normally has slapped cheek disease only once in a lifetime. This is because antibodies made during the infection protect one from future infections with this same virus.

Parvoviruses are among the smallest DNA-containing viruses known to infect mammals (hence the name parvus, which is Latin for small). The only parvovirus known to be pathogenic in humans is parvovirus B19, discovered in 1974 whilst testing for serum hepatitis B antigens. It was so called because it occurred in serum sample 19, panel B. It is a single-strand DNA virus with no lipid coat, which makes it very resistant to the normal means of killing viruses, such as disinfectants and freezing.

Parvovirus is an extremely common infection. Approximately 60% of adults are seropositive to parvovirus B19 by the age of 20 years. The most common clinical encounter with parvovirus B19 is as the causative agent of erythema infectiosum (fifth disease).

Infectivity and transmission
•Transmission is usually via respiratory secretions, but it can also be passed on via blood transfusion, bone marrow transplant, other blood products (but not intramuscular immunoglobulins), and from mother to baby via the placenta.
•The incubation period for clinical erythema infectiosum is 13-18 days. The illness is infective from 10 days pre-rash until the onset of the rash. Once the rash appears, it is no longer infectious.
•Infectivity is medium. For susceptible individuals during epidemics, the attack rate is 50% for household contacts and schoolchildren, and 30% for teachers.
•One attack confers lifelong immunity

Symptoms of slapped cheek disease
May be asymptomatic (about 25 percent of infections); or may present only with nonspecific coryzal symptoms (common).
Prodromal symptoms are mild but may include headache, rhinitis, low-grade fever and malaise. Less commonly, nausea, diarrhoea, abdominal pain or arthropathy may develop.
After 3-7 days, the classic ‘slapped cheek’ rash appears as erythema on the cheeks, sparing the nose, regions around the eyes and the mouth. This disappears after 2-4 days.

Rash
Typically, the rash looks like a bright red scald on one or both cheeks. It looks as if the cheek(s) have been slapped. Sometimes there is just a blotchy redness on the face. The rash is painless.
Sometimes a more widespread faint rash appears on the body, arms, and legs. Occasionally, the rash on the face and body keeps fading and returning several times for up to four weeks. However, it is more common for the rash to come and go completely within a few days.

Other symptoms
Although the rash can look quite dramatic, the illness itself is usually mild. Usually one feels not so ill. Headache or mild temperature (fever) for a few days may occur before the rash appears. Occasionally, mild pain and stiffness develop in one or more joints for a few days. This is more common in adults than children.
One the other hand, around one in five people who become infected with this virus do not develop any symptoms at all. Some people just have a fever and feel generally unwell, without any rashes.

Tests for slapped cheek disease
This condition is usually diagnosed by the appearance of the classical rash on the cheeks.
A blood test is sometimes performed. This will show if one has the disease and can also show if you have had this disease in the past, although, if you have had the disease in the past (even if you had it without developing any symptoms) then you will be immune to it.

Complications
Usually there are no complications. Rarely, the aching joint symptoms last for some time after the other symptoms have gone. The only times the illness may become more serious are:

Sickle cell disease
In children with some types of hereditary anaemia such as sickle cell disease, beta-thalassaemia and hereditary spherocytosis. This virus can cause these types of anaemia to become suddenly much worse.

Reduced immunity
In people with a weakened immune system. If you have leukaemia or cancer, have had an organ transplant or have HIV infection then you may develop a more serious illness with this infection.

Risk to pregnancy
In pregnant women. Most pregnant women are immune to this virus, or will not be seriously affected if they become infected by it. However, like some other viruses, the virus that causes slapped cheek disease can sometimes harm an unborn child. Miscarriage is more common in women who are infected with this virus before 20 weeks of pregnancy. Therefore, if you are pregnant, keep away from people who have slapped cheek disease. If you are pregnant and have been in contact with a person with the virus then your doctor may arrange for you to have a blood test.

Treatment
One does not usually need any treatment. If you have a headache, temperature or aches and pains, then painkillers such as paracetamol or ibuprofen will help.
Although, in those who develop complications (which is very rare) treatment and special hospitalization may be required.

Preventing slapped cheek disease
There is no vaccine or treatment that prevents this infection. Frequent handwashing reduces the risk of this infection been transmitted to other people, hence promoting the culture of routine hand washing with soap remain ever a very important public health message.
There is no benefit of disallowing the child from going to school or one not going to work. since if one has this infection one is only infectious before the rash developed and not after, when it only becomes obvious.