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van den Hof S, Meffre CM, Conyn-van Spaendonck MA, Woonink F, de Melker HE, van Binnendijk RS.van den Hof S, et al.Emerg Infect Dis. 2001;7(3 Suppl):593-7. doi: 10.3201/eid0707.010743.Emerg Infect Dis. 2001.PMID: 11485681Free PMC article.