. 2017 May 3;216(3):305–316. doi: 10.1093/infdis/jix199

Table 4.

Incidence Rates and Hazard Ratios for Protection With Prior Rotavirus Infection

No. of Previous Rotavirus Infections	Subsequent Rotavirus Infection
	Overall				Countries Using Vaccine				Countries not Using Vaccine
	Events	IR	Unadjusted HR	Adjusted HR (95% CI)	Events	IR	Unadjusted HR	Adjusted HR (95% CI)	Events	IR	Unadjusted HR	Adjusted HR (95% CI)
0	1657	1.376			571	1.333			1086	1.399
1	929	0.649	0.471	0.439^a (.401–.481)	248	0.425	0.319	0.286^a (.241–.338)	681	0.802	0.573	0.531^a (.478–.590)
2	307	0.509	0.369	0.304^a (.261–.355)	68	0.450	0.337	0.271^a (.205–.358)	239	0.528	0.377	0.319^a (.266–.383)
≥3	92	0.424	0.307	0.222^a (.176–.280)	26	0.719	0.539	0.360^a (.238–.545)	66	0.365	0.260	0.197^a (.150–.258)
	Subsequent Rotavirus Diarrhea
0	139	0.115			13	0.030			126	0.162
1	178	0.124	1.077	1.178 (.916–1.515)	46	0.079	2.601	1.305 (.564–3.022)	132	0.156	0.958	1.161 (.889–1.516)
2	64	0.106	0.918	0.795 (.561–1.125)	17	0.112	3.703	1.254 (.490–3.210)	47	0.104	0.640	0.750 (.509–1.105)
≥3	27	0.124	1.077	0.673 (.409–1.106)	3	0.083	2.733	0.495 (.114–2.152)	24	0.133	0.816	0.774 (.456–1.315)

Age- and site-adjusted incidence rates and hazard ratios.

Abbreviations: CI, confidence interval; HR, hazard ratio; IR, incidence rate.

^a P < .001.