Abstract. The Pediatric Health Information System (PHIS) database collects admission, diagnostic, and treatment data among 44 children's hospitals across the United States (U.S.) and presents an opportunity for travel-associated infectious disease (TAID) surveillance. We calculated cumulative incidence rates among children admitted to 16 PHIS hospitals for dengue, malaria, and typhoid, and pooled TAID using discharge codes from 1999 to 2012. We compared incidence rates before, during, and after the 2007-2009 economic recession. Among 16 PHIS hospitals during the study period (1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012), incidence of dengue and pooled TAID (malaria, dengue, typhoid fever) increased significantly, and rates of malaria and typhoid trended upward. Admissions for dengue and pooled TAIDs increased significantly among 16 children's hospitals across the United States from 1999 to 2012. The PHIS database may provide a useful surveillance tool for TAIDs among children in the United States.International travel to other countries has increased 5% in the United States and 48% worldwide in the last decade, and more travelers visit low-and middle-income countries (LMICs) than ever before.1 As many as 8% of U.S. travelers seek medical care, and many more suffer from milder illness while abroad.2-4 A significant proportion of the 62 million annual U.S. international travelers develops illness after returning to the United States with infections that may be unfamiliar to local health-care providers.5-7 Estimating incidence rates of non-endemic diseases may help public health officials direct educational resources and raise awareness among local practitioners.Currently, surveillance systems for travel-associated infectious diseases (TAIDs) in the United States are limited. Many TAIDs are reportable to state health departments, but reporting is often unreliable. 8 The GeoSentinel Surveillance Network (GSSN) is a system of 57 travel disease clinics worldwide, including 15 clinics in the United States. Although the GSSN obtains robust clinical and diagnostic information, it surveys only those seeking care at specialty travel clinics, and only 7% of GSSN patients are children.
1The Pediatric Health Information System (PHIS) database was established to collect administrative and financial data from pediatric hospitals across the Unites States. More recently, the database has been augmented (PHIS+) to also collect clinical, laboratory, treatment, and outcome data at multiple health-care settings (inpatient, outpatient, and emergency departments [EDs]) among 44 freestanding children's hospitals across the United States. 9,10 It offers an opportunity for objective hospitalized TAID surveillance among the greater than 5 million children hospitalized annually at these institutions. 11 We evaluated the PHIS database as a potential TAID surveillance tool by determining cumulative incidence rates of three TAIDs (malaria, dengue, and typhoid fever) among PHIS hospitals over a 14-year peri...