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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.
Losonczy KG, White LR, Brock DB.Losonczy KG, et al.Public Health Rep. 1998 May-Jun;113(3):273-80.Public Health Rep. 1998.PMID: 9633876Free PMC article.