4Flu - an individual based simulation tool to study the effects of quadrivalent vaccination on seasonal influenza in Germany

Table 4 Sensitivity analysis exploring the influence of the basic reproduction number R ₀

R ₀	Influenza A		Influenza B			Prevented
R ₀	No vaccination	TIV or QIV	No vaccination	TIV	QIV	QIV-TIV	%
1.2	5880	1954	3054	1400	1075	325	9.5
1.2	(5823–5936)	(1923–1985)	(3018–3089)	(1379–1422)	(1056–1095)	(306–344)	(8.9-10.1)
1.3	7221	3061	3754	1999	1626	373	7.3
1.3	(7151–7290)	(3018–3104)	(3709–3798)	(1970–2028)	(1599–1652)	(350–396)	(6.8-7.7)
1.4	8359	4106	4363	2541	2167	374	5.5
1.4	(8276–8442)	(4055–4158)	(4311–4415)	(2506–2577)	(2133–2201)	(350–398)	(5.2-5.9)
1.5	9302	5009	4889	3063	2677	386	4.8
1.5	(9209–9395)	(4946–5071)	(4830–4947)	(3021–3105)	(2638–2717)	(360–411)	(4.4-5.1)
1.575	9820	5597	5229	3346	2951	395	4.3
1.575	(9750–9891)	(5550–5643)	(5183–5275)	(3313–3379)	(2920–2982)	(376–414)	(4.1-4.5)
1.6	10154	5787	5345	3482	3086	396	4.2
1.6	(10051–10256)	(5716–5858)	(5280–5410)	(3435–3529)	(3041–3132)	(370–422)	(3.9-4.5)
1.7	10893	6510	5736	3880	3469	411	3.9
1.7	(10784–11002)	(6433–6587)	(5664–5809)	(3826–3934)	(3419–3518)	(385–437)	(3.7-4.2)
1.8	11494	7116	6060	4218	3820	398	3.5
1.8	(11374–11614)	(7032–7200)	(5982–6138)	(4160–4277)	(3765–3875)	(372–424)	(3.3-3.7)
1.9	12063	7669	6383	4523	4139	383	3.1
1.9	(11935–12190)	(7578–7760)	(6301–6466)	(4461–4584)	(4081–4198)	(357–409)	(2.9-3.3)
2.0	12354	8183	6640	4790	4404	385	3.0
2.0	(12227–12480)	(8087–8279)	(6550–6731)	(4724–4855)	(4342–4467)	(359–411)	(2.8-3.2)

Average annual results (with 95% confidence intervals) obtained for the 20 year evaluation period (calculated from 1,000 simulations for each combination of R ₀ and vaccination strategy in a simulated population of about 80,000 individuals (2,000 simulations each for the baseline value of R ₀ = 1.575; boldface line). The last column shows what percentage of all influenza A and B infections which occur under TIV vaccination can additionally be prevented by QIV.