BACKGROUND: On 20 September 2022, the Ugandan Ministry of Health declared an outbreak of Ebola disease caused by Sudan ebolavirus. METHODS: From 6 October 2022 to 10 January 2023, Centers for Disease Control and Prevention (CDC) staff conducted public health assessments at five US ports of entry for travellers identified as having been in Uganda in the past 21 days. CDC also recommended that state, local and territorial health departments ('health departments') conduct post-arrival monitoring of these travellers. CDC provided traveller contact information, daily to 58 health departments, and collected health department data regarding monitoring outcomes. RESULTS: Among 11 583 travellers screened, 132 (1%) required additional assessment due to potential exposures or symptoms of concern. Fifty-three (91%) health departments reported receiving traveller data from CDC for 10 114 (87%) travellers, of whom 8499 (84%) were contacted for monitoring, 1547 (15%) could not be contacted and 68 (1%) had no reported outcomes. No travellers with high-risk exposures or Ebola disease were identified. CONCLUSION: Entry risk assessment and post-arrival monitoring of travellers are resource-intensive activities that had low demonstrated yield during this and previous outbreaks. The efficiency of future responses could be improved by incorporating an assessment of risk of importation of disease, accounting for individual travellers' potential for exposure, and expanded use of methods that reduce burden to federal agencies, health departments, and travellers.

On September 20, 2017, Hurricane Maria made landfall in Puerto Rico as a Category 4 storm, with sustained winds of 130–156 miles per hour, and 15–40 inches of rain causing catastrophic flash floods. The storm destroyed electricity and communication systems, left large areas without water service, and caused widespread damage to critical infrastructure, transportation, health care, and agriculture. On the sixth day after the event, 58 (84%) of 69 hospitals on the island had no electric power or fuel for generators (1). The devastation led to declaration of a major disaster, just 10 days after a similar declaration for Hurricane Irma, a Category 5 storm that left 1 million Puerto Ricans without electricity after its center passed approximately 57 miles north of Puerto Rico (2,3). Although the island’s entire population was affected by Hurricane Maria, the poorer, more remote, and economically disadvantaged communities, as well as those with larger numbers of bedridden and elderly persons, fared worse (4) because they had less access to already depleted health care services, more fragile homes, and no alternative means for electricity generation.