Modeling the spread of polio in an IPV-vaccinated population: lessons learned from the 2013 silent outbreak in southern Israel

Table 1 List of the transmission model parameters

Parameter	Meaning	Value/prior distribution	Source/ref
N	Modeled population size^a	From 49,692 on September 15, 2012, to 67,248 on December 31, 2014^b (Additional file 1: Figure S2)	Israeli Ministry of Health [11, 12]
d _L	Mean duration of latent period	4 days	[35, 36]
d _I	Mean duration of infectious period	U (7,49) days	[8, 25–30]
\( \overline{R} \)	Mean reproductive number	U (1,10)	[37]
δ	Amplitude of seasonal variation in transmission^c	N (1,0.414)^d	[16]
ϕ	Peak day of seasonal transmission	N (156,17.55)^d	[16]
ρ	Per-dose efficacy of OPV	N (0.56,0.23)	[23]
t ₀	Initiation time of the outbreak	U (Sep 15, 2012 to Feb 6, 2013)^e	[4, 5]

^aThe number of children under 10 in the Bedouin population of southern Israel that were not vaccinated with OPV as part of their routine vaccination schedule prior to the outbreak (including children born after the initiation of the outbreak)
^bBased on available data from the Israeli Ministry of Health for October 2013 and extended for the whole time period using a birth rate of 3.5 % and a population size of 220,000 for the whole Bedouin population in southern Israel on 2013 (see Additional file 1 for details)
^cDefined using the normalized mean seasonal variation estimated across 10 southern US states during the pre-vaccine era, so that δ = 0 means no seasonal variation while δ = 1 means seasonal variation equal to the normalized mean seasonal variation of the southern US states (see Additional file 1 for details)
^dBased on the variance in the estimates of the seasonal variation in 10 southern US states during the pre-vaccine era (see Additional file 1 for details)
^eBased on the results of a phylogenetic analysis and the initial finding of WPV1 using ES (see Additional file 1 for details)

ISSN: 1741-7015