Dengue transmission is cyclic and large outbreaks every 3-4 years can be expected. During the COVID-19 pandemic, we saw moderate transmission of dengue in some regions and low transmission in others leading to an accumulation of people without immunity to certain dengue virus serotypes. However, the data on the circulating dengue serotypes is limited.  

Since the beginning of 2023, ongoing transmission, combined with an unexpected spike in dengue cases has resulted in close to a historic high of over five million cases and more than 5000 dengue-related deaths reported in over 80 countries/territories and five WHO regions: Africa, Americas, South-East Asia, Western Pacific and Eastern Mediterranean Regions globally (Figure 1). Close to 80% of these cases, or 4.1 million, have been reported in the Region of the Americas. Dengue is the most widespread arbovirus and causes the highest number of arboviral disease cases in the Region of the Americas, with cyclic epidemics recurring every 3 to 5 years. In addition, clusters of autochthonous dengue have been reported in the WHO European Region. However, these numbers are likely an underestimate of the true burden as most of the primary infections are asymptomatic and dengue reporting is not mandatory in many countries.