Fifth disease is caused by a virus called parvovirus B19. It commonly infects children and typically causes a mild rash that may resemble a “slapped-cheek”. Other symptoms that can occur include joint pain (arthralgia), fever and general flu-like symptoms. Fifth disease does not have any lasting effects in healthy children and adults. However if contracted when pregnant or immuno-compromised (a weak immune system), complications may arise.

Yes! An adult or child who is not immune can be infected with fifth disease and either have no symptoms at all or have one or all of fever, arthralgia and flu-like symptoms. In cases of pregnant women and the immuno-compromised, special vigilance should be practised. When symptoms appear, an individual is no longer infectious. This is the primary reason why fifth disease is very difficult to avoid. If you are concerned that you may not be immune to the disease (i.e. that you have never had fifth diseae), you should contact your doctor and ask to have a test.

How does somebody get infected with fifth disease?

Fifth disease is transmitted through respiratory droplets and contact with infected blood products. The incubation period (the time between the initial infection and the onset of symptoms) is usually between 4 and 21 days. People with fifth disease are most contagious before the onset of symptoms.

Does everyone who gets the infection become sick?

No. Approximately 20% of people who get parvovirus B19 (fifth disease) never show symptoms. Therefore, individuals who are infected often never realise it. Hence, the only definitive way to know if you have been infected is to have a test. If you are concerned, contact your health care provider.

How is fifth disease diagnosed?

Often a clinician can diagnose fifth disease by observing the characteristic “slapped-cheek” rash. In some cases, however, where symptoms are not evident; a blood test must be carried out. When your sample of blood arrives in the laboratory, testing is carried out for specific antibodies that your body produces in response to fifth disease. If immunoglobulin M (IgM) antibody to parvovirus B19 is detected, the test result shows that you have had or currently have a recent infection. If immunoglobulin G (IgG) antibodies are present, immunity to fifth disease is indicated. If IgG and IgM antibodies are absent, you are at risk of picking up the infection.

How are parvovirus B19 infections treated?

Treatment of symptoms such as fever, arthralgia or itching can be undertaken with medication (e.g. ibuprofen, aspirin etc.).The small minority of people with immune problems may need to be hospitalised to receive blood transfusions.

How am I treated if I am pregnant and contract fifth disease?

Pregnant women who contract the disease may have to have weekly ultrasound scans to ensure the fetus is unaffected. If the fetus is infected, an intrauterine blood transfusion may need to be carried out. This procedure prevents the fetus becoming dangerously anemic. For more information on this procedure, please click on treatment & diagnosis or contact your health care provider. A simple blood test can tell you if your baby has fifth disease or if you have it yourself.

My dog has been diagnosed with parvovirus, can I catch it?

No! There are many different types of parvoviruses. Each type is species-specific. This means that canine parvovirus (dog parvovirus) only affects dogs, human parvovirus only affects humans and cat parvovirus only affects cats.

Is there a way that I can be protected from fifth disease while pregnant?

Unfortunately there is no vaccine or medication to prevent fifth disease infection. Frequent hand washing and being aware of any outbreaks in your area is recommended when pregnant.

How will I know if I am at risk of infection?

Approximately 50-60% of adults have been infected with fifth disease at some stage in the past. However, if you are unsure as to whether you have the infection, a simple blood test can be carried out. Your doctor will be happy to discuss this test for you. Please click on our printable Information for the Doctor, which will give your doctor up-to- date information on fifth disease.