The Clinical Impact and Cost-effectiveness of Measles-Mumps-Rubella Vaccination to Prevent Measles Importations Among International Travelers From the United States

Abstract

Background Measles importations and the subsequent spread from US travelers returning from abroad are responsible for most measles cases in the United States. Increasing measles-mumps-rubella (MMR) vaccination among departing US travelers could reduce the clinical impact and costs of measles in the United States. Methods We designed a decision tree to evaluate MMR vaccination at a pretravel health encounter (PHE), compared with no encounter. We derived input parameters from Global TravEpiNet data and literature. We quantified Riskexposure to measles while traveling and the average number of US-acquired cases and contacts due to a measles importation. In sensitivity analyses, we examined the impact of destination-specific Riskexposure, including hot spots with active measles outbreaks; the percentage of previously-unvaccinated travelers; and the percentage of travelers returning to US communities with heterogeneous MMR coverage. Results The no-encounter strategy projected 22 imported and 66 US-acquired measles cases, costing $14.8M per 10M travelers. The PHE strategy projected 15 imported and 35 US-acquired cases at $190.3M per 10M travelers. PHE was not cost effective for all international travelers (incremental cost-effectiveness ratio [ICER] $4.6M/measles case averted), but offered better value (ICER <$100 000/measles case averted) or was even cost saving for travelers to hot spots, especially if travelers were previously unvaccinated or returning to US communities with heterogeneous MMR coverage. Conclusions PHEs that improve MMR vaccination among US international travelers could reduce measles cases, but are costly. The best value is for travelers with a high likelihood of measles exposure, especially if the travelers are previously unvaccinated or will return to US communities with heterogeneous MMR coverage.

Vaccine Refusal and Measles Outbreaks in the US

“…Modeled analyses of various targeted vaccination strategies to mitigate this risk suggested that increased vaccine uptake among schools with the lowest coverage, specifically among individuals with nonmedical exemptions, was projected to have the greatest effect on outbreak potential. Similarly, Hyle et al evaluated the cost-effectiveness of vaccination strategies for international travelers during pretravel health encounters for preventing importation-related measles outbreaks and concluded that targeted vaccination of individuals traveling to destinations with a high risk of measles exposure and those returning to communities with heterogeneous vaccination rates would be expected to provide the most value.…”

Epidemics, Air Travel, and Elimination in a Globalized World: The Case of Measles

“…For the United States and other governments concerned with importation of diseases like measles, this work highlights two important priorities. First, reducing the risk contributed by resident travelers is essential, accomplished through increased risk awareness 55 and vaccination coverage 56 among travelers (particularly high-risk travelers and those from communities with heterogeneous vaccination coverage 57 ). Second, this work stresses the tremendous value of information to both domestic biosecurity and global disease control.…”

The Clinical and Economic Impact of Measles-Mumps-Rubella Vaccinations to Prevent Measles Importations From US Pediatric Travelers Returning From Abroad

“…We adapted a previously published decision tree (TreeAge, Williamstown MA) for MMR vaccination in travelers and compared 2 strategies among pediatric international travelers: (1) No pretravel health encounter (PHE) and (2) PHE [ 12 ]. Travelers in both strategies begin the simulation with an age-dependent “baseline vaccination status” of 0, 1, or 2 MMR vaccination(s).…”