Epidemiologic Tendencies of Dengue in U.S. Territories, 2010–2020

Outcomes

Throughout 2010–2020, a complete of 30,903 instances had been reported to ArboNET from American Samoa, Guam, Puerto Rico, and USVI; 21,705 (70.2%) had been confirmed and 9,198 (29.8%) had been possible (Table 1). The best variety of dengue instances occurred amongst individuals aged <20 years, accounting for roughly half (15,640 (50.6%)) of reported instances. A majority of instances occurred in males, accounting for 16,808 (54.4%) of all instances. Roughly 2% (584) of all instances had been categorized as extreme dengue. A complete of 10,037 (32.4%) individuals with dengue had been hospitalized, and 68 (0.2%) deaths had been reported. Journey to a rustic with native transmission of dengue within the 2 weeks earlier than symptom onset was reported in 28 (0.1%) instances.

Puerto Rico

Throughout 2010–2020, the bulk (29,862 (96.6%)) of dengue instances had been reported from Puerto Rico (Figure 1). Annual incidence per 1,000 inhabitants was highest throughout the two outbreaks in 2010 and 2013, 2.9 and a pair of.6, respectively (Figure 2). Amongst all reported instances from Puerto Rico, 20,675 (69.2%) had been confirmed and 9,187 (30.8%) had been possible; 54.6% of dengue instances had been in males. Roughly 50% of reported instances in Puerto Rico occurred amongst individuals aged <20 years, with the ten–19-year-old age group accounting for 37.3% of instances. The best incidence and hospitalization charges additionally occurred amongst youngsters aged 10–14 and 15–19 years (Figure 3). In Puerto Rico, 32.6% of individuals with dengue had been hospitalized and 68 dengue-associated deaths had been reported throughout 2010–2020; the best variety of deaths (n = 10) occurred amongst individuals aged >70 years, though six (8.8%) of the deaths occurred amongst individuals aged <20 years (Figure 4). Virtually all (>99%) instances of dengue in Puerto Rico had been domestically acquired.

American Samoa

Throughout 2010–2020, American Samoa accounted for 660 (2.1%) of all reported instances within the U.S. territories (Determine 1). Annual incidence per 1,000 inhabitants was highest in 2017, reaching 10.2 per 1,000 inhabitants (Determine 2). All dengue instances had been confirmed, and 50.3% had been in females. The best case numbers and charges occurred amongst individuals aged <20 years; 68.0% of reported instances occurred amongst individuals aged <20 years, and 45.9% occurred amongst individuals aged 10–19 years. The proportion of individuals with dengue instances hospitalized in American Samoa (45.5%) was just like Puerto Rico (Desk 1); the best incidence charges and hospitalizations occurred within the 10–14 and 15–19-year-old age teams (Figure 5). No dengue-associated deaths had been reported, and one travel-associated case was reported.

U.S. Virgin Islands

Throughout 2010–2020, USVI accounted for 353 (1.1%) of all reported instances within the U.S. territories (Determine 1). Annual incidence per 1,000 inhabitants was highest throughout the 2012–2013 outbreak with an annual incidence of 1.6 in 2013 (Determine 2). Virtually all (96.9%) reported instances in USVI had been confirmed, and 53.3% had been in females. Roughly one third of reported instances occurred amongst youngsters and adolescents aged <20 years, with a majority (21.5%) within the 10–19-year-old age group. The 20–29-year-old age group was the second most affected age group with 15.0% of instances. Three (0.8%) individuals with dengue had been hospitalized, and no dengue-associated deaths had been reported. The best incidence fee occurred amongst youngsters aged 10–14 years (Figure 6). All reported instances had been domestically acquired.

Guam

Throughout 2010–2020, Guam accounted for 28 (0.1%) of all reported instances within the U.S. territories. All instances had been confirmed and occurred in 2019 and 2020; nevertheless, practically one half of all reported instances (13 (46.4%)) had been journey related. A couple of half (60.7%) of instances had been in males. Just like the opposite U.S. territories, the ten–19-year-old age group was most affected, with roughly 25% of reported instances. Not like the opposite territories, the following most affected age group was individuals aged 30–39 years, accounting for 21.4% of instances. Thirty-two p.c of individuals with dengue had been hospitalized, and no dengue-associated deaths had been reported (Desk 1).

Serotype Distribution in Puerto Rico, USVI, and American Samoa

A complete of 21,329 confirmed instances from Puerto Rico (21,194), USVI (119), and American Samoa (16) had DENV serotype knowledge reported to or carried out by the CDC Dengue Department Laboratory (Table 2). In Puerto Rico, the bulk (72.9%) of instances had been DENV-1, adopted by DENV-4 (24.1%), which had been related to the big dengue outbreaks throughout 2010–2013 (Figure 7). Concurrent with the emergence of chikungunya in 2014 and Zika in 2016, total dengue case counts decreased from 2015 to 2019, with all 4 DENV serotypes circulating at low ranges. In 2019 and 2020, dengue exercise elevated barely, with all domestically acquired instances recognized as DENV-1, along with a number of travel-associated instances of DENV-2 and DENV-3. In USVI, DENV-1 and DENV-4 had been the 2 circulating dengue serotypes throughout the outbreaks throughout 2012–2013, with DENV-1 accounting for 80.7% of instances with serotype obtainable. In American Samoa, restricted serotype knowledge had been obtainable, though DENV-2 (n = 2) and DENV-3 (n = 14) instances had been reported.