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Schillie S, Vellozzi C, Reingold A, Harris A, Haber P, Ward JW, Nelson NP.Schillie S, et al. Among authors: vellozzi c.MMWR Recomm Rep. 2018 Jan 12;67(1):1-31. doi: 10.15585/mmwr.rr6701a1.MMWR Recomm Rep. 2018.PMID: 29939980Free PMC article.