Measles outbreak response vaccination in the Federated States of Micronesia

Measles is an acute, highly infectious, viral disease transmitted through respiratory droplets and aerosolized droplet nuclei.1 It is characterized by fever, cough, coryza, conjunctivitis and generalized maculopapular rash typical of the disease (Figure 1). ... After 20 years with no reported measles cases, a widespread outbreak occurred in the Federated States of Micronesia (FSM), an Oceanic island nation just north of the Equator.2 From February to August 2014, a multi-state outbreak affected three of the four FSM states. As part of a systematic outbreak-response following the first laboratory-confirmed case of measles, an emergency mass vaccination campaign was launched successively in each FSM state, to interrupt transmission and contain the outbreak. Vaccinating the target population of 82 472—80% of the national population—required concerted collaborative efforts of FSM state and national immunization programmes with support from all three levels of government and international partners. Mass vaccination campaigns are major logistical undertakings which require extensive preparation and planning for the procurement, management and distribution of measles vaccines and supplies (Figure 2). The campaign logistics and implementation were even more challenging in FSM, due to its unique geographical expanse, scattered over 607 widely dispersed islands spanning 1700 miles across the western Pacific Ocean. Some of the nation’s isolated islands and atolls are only accessible by boat, an important mode of transportation for the outreach vaccination teams (Figure 3). When boats could not reach the shore during low tides, immunization staff had to carry the campaign supplies over the reef (Figure 4).