Age-shifting in malaria incidence as a result of induced immunological deficit: a simulation study

Malaria Journal

Table 1 Simulation parameters

Variable	Levels simulated for PEV and SMC
Model variants	(1) R0000 base model
	(2) R0068 heterogeneity in transmission: within-host variability
	(3) R0131 immunity decay in effective cumulative exposure
	(4) R0132 immunity decay in immune proxies
	(5) R0133 immunity decay in both immune proxies & effective cumulative exposure
	(6) R0670 heterogeneity in susceptibility to co-morbidity
Population size	100,000
Age-group upper bounds (years)	1, 2, 3, 4, 5, 6, 10, 12, 16, 20, 30, 40, 50, 60, 70, 99
Survey intervals	Yearly surveys for 20 years
Transmission pattern	Seasonal, West Africa
EIR (infectious bites per person per year)	0.1^a, 1, 2, 4, 8, 16, 64, 256
Uncomplicated case management^b (%)	0, 5, 40
Inpatient care for severe cases^c (%)	0, 100
Vaccination coverage (%)	0, 100

	PEV only	SMC only
Cohort age	EPI cohort 6, 10, 14 weeks old	All children aged between 3–59 months
Initial efficacy against infection (%)	62.7	100
Half-life (years)	1.12	0.175
Weibull decay shape parameter (k)	1 (exponential decay)	3.300 (slow decay, followed by quick decay)
Number of simulations	67,680	10,080

^aEIR of 0.1 was not simulated, but any predictions for this level are taken as 10% of EIR 1.
^bProbability of access to treatment for uncomplicated disease during a 5-day period.
^cProbability of access to hospital care (or equivalent) for severe disease during any 5 day period.

ISSN: 1475-2875