Hepatitis A infections are surging this year across Colorado - with dozens of people most recently exposed at a Colorado Springs homeless shelter.
Across the state, one person has died and at least 57 people have tested positive for the liver disease this year - more than double Colorado's typical annual caseload, said Dr. Rachel Herlihy, the Colorado Department of Public Health and Environment's state epidemiologist.
El Paso County ranks as the hardest hit, with 12 cases so far this year, said Shannon Rowe, a county epidemiologist. Half of those people infected needed to be hospitalized, and all are recovering.
The surge comes as several other states deal with outbreaks of the virus, which is found in fecal matter and is spread through sex or through contaminated food or water. Poor hand washing is often to blame.
"What Colorado is experiencing is sort of mirroring what's happening across the country, and even actually in Western Europe, other parts of the globe as well," Herlihy said.
Some outbreaks, such as one San Diego, ran rampant through homeless communities.
In Colorado and El Paso County, most cases involved men having sex with men, or people visiting adult bookstores or adult arcades, health officials said.
Few of the infected people here have been homeless. But one who was recently forced El Paso County health officials to swiftly open two temporary clinics to halt its spread.
Last week, county health officials gave vaccination and immunoglobulin shots to 62 people exposed to a person with hepatitis A who stayed at the Salvation Army's homeless shelter, 709 S. Sierra Madre St.
That person had recently been in San Diego, though lab tests have yet to confirm whether that person's infection was linked to the outbreak there, Rowe said.
County health officials remain concerned that not everyone possibly exposed at the shelter received prophylaxis shots.
They are working with several homeless service providers to help them identify symptomatic clients. For example, the city's two largest homeless shelters have been asked to screen visitors for signs of the illness.
"We're trying to hit it from all the angles we can," said Danielle Oller, a county health department spokeswoman.
Health officials also are urging other residents to get vaccinated - especially those at higher risk for the disease. They include anyone in those affected populations, people with chronic liver disease or people traveling to places where the disease is common.
"It is a vaccine that is given now routinely to all children - but not all adults, because that recommendation has only been in place for a number of years," Herlihy said. "So we do know there is a substantial proportion of the adult population in Colorado that is quite vulnerable to infection."
The disease can damage the liver, and it can be deadly.
Symptoms include jaundice, fatigue, severe stomach pain, nausea and diarrhea. They typically don't show for two weeks to nearly two months after a person becomes infected - meaning people exposed to the disease can spread it without knowing they're sick. That makes controlling the virus difficult, Herlihy said.
Hepatitis A differs from hepatitis B and C in that it is not chronic - meaning people can recover and gain immunity from it.
The last time so many people in El Paso County were infected was in 2013, when 17 cases were reported. Eleven of those people were sickened in an outbreak tied to contaminated pomegranate seeds.
