In recent years, several high-profile attacks on hospitals providing medical aid in conflict settings have raised international concern. The International Humanitarian Law prohibits the deliberate targeting of health care settings. Violation of this law is considered a war crime and impacts both those delivering and receiving medical aid.

While it has been demonstrated that both aid workers and health care settings are increasingly being targeted, little is known about the trends and characteristics of security incidents involving aid workers in health care compared to non-health care settings.

Data from the publicly available Aid Worker Security Database (AWSD) containing security incidents involving humanitarian aid workers world-wide were used in this study. The security incidents occurring from January 1, 1997 through December 31, 2016 were classified by two independent reviewers as having occurred in health care and non-health care settings, and those in health care settings were further classified into five categories (hospital, health clinic, mobile clinic, ambulance, and vaccination visit) for the analysis. A stratified descriptive analysis, χ2 Goodness of Fit test, and Cochran-Armitage test for trend were used to examine and compare security incidents occurring in health care and non-health care settings.

Among the 2,139 security incidents involving 4,112 aid workers listed in the AWSD during the study period, 74 and 2,065 incidents were in health care settings and non-health care settings, respectively. There was a nine-fold increase from five to 45 incidents in health care settings (χ2 = 56.27; P < .001), and a five-fold increase from 159 to 852 incidents in non-health care settings (χ2 = 591.55; P < .001), from Period 1 (1997-2001) to Period 4 (2012-2016). Of the 74 incidents in health care settings, 23 (31.1%) occurred in ambulances, 15 (20.3%) in hospitals, 13 (17.6%) in health clinics, 13 (17.6%) during vaccination visits, and six (8.1%) in mobile clinics. Bombings were the most common means of attack in hospitals (N = 9; 60.0%), followed by gun attacks (N = 3; 20.0%). In health care settings, 184 (95.3%) were national staff and nine (4.7%) were international staff.

Security threats are a growing occupational health hazard for aid workers, especially those working in health care settings. There is a need for high-quality data from the field to better monitor the rapidly changing security situation and improve counter-strategies so aid workers can serve those in need without having to sacrifice their lives.