Table 3. Univariable and multivariable mixed-effects logistic regression model analysing socio-demographic characteristics and risk factors^a associated with HEV infection in blood donors, Italy 2017–2019 (n = 6,235).

		n	IgG anti-HEV (%)	Univariable logistic model			Multivariable logistic model
				OR	95% CI	p value	OR	95% CI	p value
Sex	Female	1,870	7.3	1	Reference		1	Reference
	Male	4,365	8.9	1.25	1.01–1.56	0.041	1.15	0.85–1.56	0.364
Age (years)	< 40	2,421	5.4	1	Reference		1	Reference
	≥ 40	3,774	10.3	1.94	1.56–2.41	< 0.0001	1.81	1.36–2.41	< 0.001
Nationality	Italian	5,883	8.6	1	Reference		1	Reference
	Foreign	74	14.9	1.81	0.91–3.60	0.089	2.77	1.06–7.24	0.038
District of birth	Urban area	5,065	7.9	1	Reference		1	Reference
	Rural area	1,170	10.6	1.33	1.05–1.67	0.017	0.87	0.60–1.27	0.479
District of residence	Urban area	4,848	8.0	1	Reference		1	Reference
	Rural area	1,387	10.0	1.25	1.00–1.57	0.049	1.13	0.79–1.60	0.506
Work experience with wild or farm animals	No	5,350	7.9	1	Reference		1	Reference
	Yes	669	13.5	1.58	1.22–2.05	0.001	1.02	0.69–1.51	0.913
Domestic contact with animalsb	No	4,187	7.6	1	Reference		1	Reference
	Yes	1,663	9.1	1.14	0.92–1.42	0.221	0.79	0.56–1.11	0.171
Contacts with pigs, wild boars or wild animals	No	4,948	6.9	1	Reference		1	Reference
	Yes	1,051	13.1	1.55	1.23–1.94	< 0.001	0.99	0.67–1.46	0.955
Contacts with other animalsc	No	3,974	6.7	1	Reference		1	Reference
	Yes	2,063	10.6	1.45	1.19–1.77	< 0.001	0.98	0.68–1.42	0.923
Hunting	No	5,898	8.0	1	Reference		1	Reference
	Yes	270	16.7	1.99	1.39–2.86	< 0.001	1.61	0.99–2.62	0.056
Gardening	No	3,753	6.8	1	Reference		1	Reference
	Yes	2,213	11.2	1.55	1.28–1.89	< 0.001	1.23	0.88–1.71	0.222
Vegetable gardening	No	4,229	7.0	1	Reference		1	Reference
	Yes	1,942	11.2	1.45	1.19–1.76	< 0.001	0.90	0.61–1.33	0.588
Eating pork liver salamid	No	4,983	6.1	1	Reference		1	Reference
	Yes	733	21.7	2.95	2.31–3.77	< 0.001	1.25	0.86–1.82	0.238
Eating uncooked liver sausagesd	No	5,098	5.5	1	Reference		1	Reference
	Yes	919	24.2	3.67	2.92–4.62	< 0.001	2.23	1.55–3.20	< 0.001
Eating uncooked pork sausagesd	No	2,418	3.1	1	Reference		1	Reference
	Yes	3,668	12.0	3.51	2.69–4.58	< 0.001	1.22	0.81–1.84	0.343
Eating uncooked wild boar sausagesd	No	4,317	6.6	1	Reference		1	Reference
	Yes	1,697	13.3	1.80	1.47–2.21	< 0.001	0.89	0.67–1.20	0.449
Eating homemade sausagesd	No	2,613	3.3	1	Reference		1	Reference
	Yes	2,560	13.6	4.15	3.20–5.39	< 0.001	3.63	2.50–5.27	< 0.001
Eating uncooked game meatd,e	No	4,779	7.4	1	Reference		1	Reference
	Yes	1,333	11.9	1.40	1.14–1.73	0.002	1.06	0.79–1.42	0.691
Eating raw seafood	No	3,566	7.7	1	Reference		1	Reference
	Yes	2,293	9.9	1.19	0.98–1.46	0.078	0.93	0.71–1.22	0.607
Eating vegetables from your own garden	No	3,241	6.9	1	Reference		1	Reference
	Yes	2,549	10.6	1.38	1.13–1.69	0.001	1.05	0.73–1.51	0.798
Travel abroad	No	1,661	8.4	1	Reference		1	Reference
	Yes	4,476	8.5	0.94	0.75–1.18	0.603	0.97	0.70–1.33	0.829

AOR: adjusted odds ratio; CI: confidence interval; HEV: hepatitis E virus; OR: odds ratio.

Missing values for each variable were not included in the analysis, they ranged from 0.6% to 8.3% for the evaluated risk factors.

^a Exposure to risk factors was assessed over a lifetime.

^b I.e. presence of an animal in the family, including farms, family livestock, etc.

^c Horses, sheep, cattle, goats, cats, dogs etc.

^d Raw or undercooked.

^e Wild boar, deer etc.