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Awofisayo-Okuyelu A, Hall I, Adak G, Hawker JI, Abbott S, McCARTHY N.Awofisayo-Okuyelu A, et al.Epidemiol Infect. 2017 Aug;145(11):2241-2253. doi: 10.1017/S0950268817001303. Epub 2017 Jul 3.Epidemiol Infect. 2017.PMID: 28669361Free PMC article.Review.