How many serotypes of Dengue virus exist?

Dengue virus is known to exist in four distinct serotypes, which are classified as DEN-1, DEN-2, DEN-3, and DEN-4. Each serotype is capable of causing the illness known as dengue fever, which can range from mild to severe. The existence of these four serotypes is critical for understanding the epidemiology and potential complications associated with dengue infections.

Infections with one serotype can lead to immunity to that specific serotype but do not confer immunity to the others, which can increase the risk of severe disease upon subsequent infections with a different serotype. This characteristic plays a significant role in the patterns of dengue outbreaks globally and is essential for vaccine development strategies and public health management of the disease.

The options suggesting fewer or more than four serotypes do not align with the current scientific consensus, underpinning the significance of recognizing the established four serotypes of the dengue virus.