An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Rodríguez-Guardado A, Asensi Alvarez V, Rodríguez Perez M, Mejuto Alvarez P, Flores-Chavez M, Alonso González P, Cartón Sánchez JA.Rodríguez-Guardado A, et al.Epidemiol Infect. 2011 Apr;139(4):539-43. doi: 10.1017/S0950268810001305. Epub 2010 Jun 14.Epidemiol Infect. 2011.PMID: 20546632