An outbreak of hepatitis A continues to spread across the country
Michigan has seen 22 deaths and 658 cases
(CNN)An outbreak of hepatitis A has spread from Southern California to states across the country, killing dozens of people and potentially sickening thousands. Michigan has been hardest-hit in terms of deaths, with 22.
The outbreak therebegan in August 2016 and, after a dropoff during the winter, continued to climb last year, according to the Michigan Department of Health and Human Services. As of January 4, there have been 658 cases in Southeast Michigan.
Fighting the outbreak was challenging in many jurisdictions due to a national shortage of the vaccine for hepatitis A.
The outbreak can be traced to transient camps and illicit drug users in San Diego, officials say.Now, California is in the middle of the biggest person-to-person outbreak of hepatitis A since the vaccine first became available in the mid-'90s, according to the California Department of Public Health. Though the virus has spread across the state, San Diego has seen the most deaths: 21, out of a reported 686 cases.
Officials say movement among the homeless population has also spread the virus to Utah and possibly Arizona and Colorado. Cases of hepatitis A in Colorado doubled in 2017, and health officials there say they are increasing specifically among "gay, bisexual and other men who have sex with unvaccinated men."
Over the weekend, officials in Utah announced a new outbreak at a convenience store in Salt Lake County that can be traced to San Diego.
"We have 97 outbreak-related cases in our county," Salt Lake County Health Department spokesman Nicholas Rupp said, adding that those cases were tied to a worker at a 7-Eleven who tested positive for the same strain of the virus as that in San Diego. "We are seeing similar hospitalization rates as San Diego, about 60%, but we have fortunately not seen any deaths."
Just south of Salt Lake, workers at two Utah County restaurants also tested positive for the virus in late December.
"In Utah, we don't require vaccinations for food workers against hepatitis A, but we are encouraging everyone who handles food to be vaccinated, and this is why," Rupp said. "And everyone should practice handwashing after being in public places to protect themselves from exposure."
Consumers who used the restroom at or ate at the two restaurants are at risk, health officials said, and those who visited the 7-Eleven and consumed any self-serve beverage, fresh fruit or items from the hot food case, such as pizza, hot dogs or chicken wings, may have been exposed. Packaged foods are not affected, according to the Health Department.
Hepatitis A is a highly contagious liver disease caused by the HAV virus. The virus is found in the feces of people with the disease and is most frequently transmitted by eating food or drinking water handled by someone who has not properly washed their hands. It also can be transmitted by sex and by illicit drug use.
Some of the most common symptoms include nausea, vomiting, fever, fatigue, loss of appetite and jaundice, or yellowing of the skin or eyes. It can take 15 to 50 days to show symptoms of the infection; however, an infected person is most contagious during the two weeks before their skin turns yellow.
Most people recover from the virus and are immune to further infection, according to the CDC, but some can develop liver failure that leads to death. That is most common in people with compromised immune systems, those older than 50 and those with other liver diseases.
According to the CDC, the hepatitis A virus is very hard to kill and can live for months outside the body. Hand sanitizers are not effective against the virus, so frequent handwashing is critical to controlling any outbreak.
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Outbreaks of hepatitis A are normally small, because the vast majority of the US population was inoculated at approximately 1 year old. GlaxoSmithKline and Merck are the only companies approved by the Food and Drug Administration to sell a hepatitis A adult or pediatric vaccine in the US.
The current outbreaks of hepatitis A, virus genotype IB, is normally not found in the US; it's more common to the Mediterranean, Turkey and South Africa. However, the current vaccine is effective against all strains of the virus.