Dengue infection raises risk of future infection

A new study details how becoming infected with the dengue virus once can put people at greater risk for infection in the future.

A team of researchers from the University of California Berkeley has examined the mechanism behind the changing dengue virus genetics and dynamics of host immunity, and have published their results in the journal Science of Translational Medicine, according to

The virus that causes dengue can be divided into four serotypes that can then be further divided into subtypes.

The Berkeley study demonstrated that a person’s prior immune response to one serotype can influence their reaction to another serotype during a subsequent infection. The difference in reactions could be significant - a mild fever versus dengue shock syndrome.

The findings could have major implications on the effort to find a cure for the disease, which infects between 50-100 million people every year.

It was known that when confronted with dengue, the human immune system reacts normally by creating antibodies to fight the infection. Unfortunately, when faced with a new serotype during a subsequent infection, those antibodies can become confused. A similar reaction can even take place within subtypes of the same serotype.

“With the second infection, the antibodies sort of recognize the new type of viruses, but not well enough to clear them from the system,” lead author Molly OhAinle of UC Berkeley’s School of Public Health said, reports. “Instead of neutralizing the viruses, the antibodies bind to them in a way that actually helps them invade the immune system’s other cells and spread.”