Perceptions and Practices of Mass Bat Exposure Events in the Setting of Rabies Among U.S. Public Health Agencies

Abstract

Current guidelines in the setting of exposures to potentially rabid bats established by the Advisory Committee on Immunization Practices (ACIP) address post-exposure prophylaxis (PEP) administration in situations where a person may not be aware that a bite or direct contact has occurred and the bat is not available for diagnostic testing. These include instances when a bat is discovered in a room where a person awakens from sleep, is a child without an adult witness, has a mental disability or is intoxicated. The current ACIP guidelines, however, do not address PEP in the setting of multiple persons exposed to a bat or a bat colony, otherwise known as mass bat exposure (MBE) events. Due to a dearth of recommendations for response to these events, the reported reactions by public health agencies have varied widely. To address this perceived limitation, a survey of 45 state public health agencies was conducted to characterize prior experiences with MBE and practices to mitigate the public health risks. In general, most states (69% of the respondents) felt current ACIP guidelines were unclear in MBE scenarios. Thirty-three of the 45 states reported prior experience with MBE, receiving an average of 16.9 MBE calls per year and an investment of 106.7 person-hours annually on MBE investigations. PEP criteria, investigation methods and the experts recruited in MBE investigations varied between states. These dissimilarities could reflect differences in experience, scenario and resources. The lack of consistency in state responses to potential mass exposures to a highly fatal disease along with the large contingent of states dissatisfied with current ACIP guidance warrants the development of national guidelines in MBE settings.

Keywords: Bats; exposures; guidelines; human; prophylaxis; rabies.

Fig. 1

The number and percentage of public health agencies (N = 45) and their reported mass bat exposure (MBE) protocol status (absent or present) based on the agency’s prior experience. Little or no MBE experience = agencies reporting no confirmed MBE events in the previous 5 years of survey; prior MBE experience = agencies with MBE event reported in previous 5 years of survey. Number of agencies are reported above each bar.

Fig. 2

The number and percentage of public health agencies (N = 45) reporting on the clarity of ACIP on investigation recommendations and PEP recommendations in the setting of mass bat exposures. Number of agencies are above each bar.

Fig. 3

Bubble graph comparing the months public health agencies (N = 45) are willing to administer PEP prior to suspected bat exposure versus the months public health agencies are willing to investigate an MBE event prior to suspected bat exposure. Bubbles that fall on the dashed lines represent agencies that retrospectively recommend PEP and investigate MBE events within the same time frame. Bubbles that are above the dashed line are agencies that are more likely to recommend PEP beyond the time span of a retrospective investigation while bubbles that fall under the dashed line are agencies that are less likely to recommend PEP during the time span of a retrospective investigation. Bubble area correlates with the number of agencies. Red = agencies with little or no experience, Blue = agencies with prior experience.