An “exceptionally” virulent variant of HIV has been detected in the Netherlands, where it has been circulating for several years, Without treatment, the variant – referred to as VB – appears capable of accelerating patients’ usual progression to advanced HIV and AIDS-related complications. The variant, which is thought to have arisen in the late 1990s, has infected 109 people in the country .People infected with VB were present in all regions of the Netherlands, but with a different distribution relative to that of non-VB individuals. Why has it taken so long to have a Hiv/AIDS vaccine ?

