The outbreak seems to be affecting mostly men, with 615 of the 694 cases (nearly 89 percent) this year in Nevada being in males.
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Recent norovirus outbreaks, more on norovirus
Nevada health officials declare syphilis outbreak in Las Vegas
This transmission electron micrograph, TEM, revealed some of the ultra structural morphology displayed by norovirus virions, or virus particles. Noroviruses belong to the genus Norovirus, and the family Caliciviridae. They are a group of related, single-s
Amanda T. Harrington, PhD, assistant professor of clinical pathology at UIC, tests specimens on Tuesday Jan. 12, 2016 using the Verigene System, made by Nanosphere based in Chicago, which helps medical professionals identify gastrointestinal infections like norovirus on the molecular level. UIC is one of the universities/hospitals that has the system. (Phil Velasquez/Chicago Tribune/TNS via Getty Images)
The Norovirus has increased tenfold in Colorado in the last 6 years, with most of the outbreaks showing up in nursing homes. Raquel Rivera cleans the private rooms and the common areas at Chateau des Mons Care and Assisted Living in Englewood, and has a rigorous cleaning regime. Since the home had an outbreak of the virus just over a week ago, along with her everyday routine of soap and disinfectant, Rivera wipes everything down with a bleach solution. She will use the bleach for at least two weeks after the conclusion of the last outbreak. Kathryn Scott Osler, The Denver Post (Photo By Kathryn Scott Osler/The Denver Post via Getty Images)
WASHINGTON, DC - June 10: Rep. Diana DeGette, D-Colo., and Rep. Gene Green, D-Texas, during the House Energy and Commerce Subcommittee on Health markup of a bill to amend the Federal Food, Drug and Cosmetic Act with the goal of improving the safety of food in the global market. (Photo by Scott J. Ferrell/Congressional Quarterly/Getty Images)
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Syphilis can be cured fairly easily with the right antibiotics if detected early, but the symptoms aren't always apparent and can progress for years undetected.
Treatment will kill the syphilis bacterium, however damage caused by the STD will not be repaired.
Officials are urging people in the area to get tested.