Projections of epidemic transmission and estimation of vaccination impact during an ongoing Ebola virus disease outbreak in Northeastern Democratic Republic of Congo, as of Feb. 25, 2019

Worden, Lee; Wannier, Rae; Hoff, Nicole A.; Musene, Kamy; Selo, Bernice; Mossoko, Mathias; Okitolonda-Wemakoy, Emile; Muyembe Tamfum, Jean Jacques; Rutherford, George W.; Lietman, Thomas M.; Rimoin, Anne W.; Porco, Travis C.; Kelly, J. Daniel

The stochastic model estimated likelihoods of the three scenarios of zero, low, and high vaccination coverage, based on how often models using the different coverage assumptions were able to pass the particle filtering step. In the estimate based on data through February 25, zero vaccination coverage was estimated substantially more likely than low or high coverage, as was also true in most earlier estimates. The lower vaccination coverage scenario was estimated more likely than the higher one. Higher vaccination coverage scenarios were estimated more likely in estimates made before October, at which time the outbreak epicenter shifted into the Projections of an EVD outbreak in Northeastern DRC conflict zone and situation reports described an increase in case counts (S5 Fig). Assuming that other transmission factors were held constant, our result may provide evidence that that geographical shift in transmission contributed to a decreased likelihood of a high vaccination scenario.