Slapped cheek syndrome, also known as Fifth Disease, is a viral infection caused by the human parvovirus B19. It is most commonly found in children aged between five and fifteen, but can occur in adults as well.
The syndrome is highly contagious and is spread through respiratory secretions, such as saliva and mucus, as well as contact with infected blood. The period of contagiousness is usually from two weeks before the onset of the rash until five days after the rash appears. This means that an infected individual can spread the virus to others during this time even if they are not showing any signs or symptoms of the disease.
Once the virus is contracted, it can take anywhere from four to twenty days for the infected person to start exhibiting symptoms of the disease. When the rash appears, the contagiousness of the virus usually begins to decrease. After five days, the virus is no longer considered contagious and the infected individual is unlikely to pass it on to others.
In summary, Slapped cheek syndrome is highly contagious and can be spread through contact with respiratory secretions and infected blood. The period of contagiousness is usually from two weeks before the onset of the rash until five days after the rash appears. After five days, the virus is no longer considered contagious.