In the Region of the Americas, between epidemiological week (EW) 1 and EW 22 of 2021, a total of 728,831 cases of arboviral disease were reported. Of those, 673,148 (92.3%) were dengue cases, 49,671 were chikungunya cases, and 6,012 were Zika cases (Figure 1).
In the Region of the Americas, the total number of cases of arboviral disease reported in 2021 as of EW 22 (728,831 cases) represents approximately a 58% relative decrease compared to the same period in 2020 (1,734,951 cases), when the COVID-19 pandemic began (Figure 2).
Since 2020, the circulation of the dengue virus and other arboviruses has been occurring simultaneously with the active transmission of the SARS-CoV-2 virus in endemic countries and territories in the Region of the Americas. Meanwhile, vaccination campaigns against COVID-19 in the Region of the Americas is ongoing and public health measures are becoming more flexible. Therefore, while heterogeneous scenarios in different countries of the Region of the Americas must be considered, the syndemic of COVID-19 and arboviral diseases will most likely continue during the next epidemic period in arbovirus-endemic areas within the Region.
Based on previous experiences during dengue epidemics, the ongoing COVID-19 pandemic and the persistence of arboviral cases in endemic areas presents a challenge for health systems across all components and levels, including epidemiological surveillance.
During the COVID-19 and dengue syndemic, co-infection with the two viruses have been reported in countries and territories of the Region of the Americas (2, 3). According to the available evidence, the severity and prognosis of these coinfected patients is not yet clear. However, it will be important to prepare health systems to respond adequately and in a timely manner to potential scenarios.
Additionally, the hurricane and tropical storm season in countries and territories of the Caribbean, Central America, and the East Coast of the United States began in June, which, depending on its magnitude and impact on dengue endemic areas, could constitute an additional burden for health systems in affected areas.
The following is the epidemiological situation of dengue, chikungunya, and Zika in the Region of the Americas.