In September 2017, we wrote about an outbreak of hepatitis A in San Diego that prompted the city’s Public Health Officer to declare a health emergency. Interestingly, the outbreak was propagated through person-to-person contact and injection drug use rather than contaminated food or water, which is traditionally the more common route of hepatitis A transmission. Since this outbreak, multiple other states across the nation have reported similar hepatitis A outbreaks, including Colorado , Michigan (also the topic of a previous Outbreak Thursday post), Utah, Arizona, and Kentucky. The highest impact of these outbreaks has been seen in homeless individuals and users of illicit drugs.

Now Indiana is reporting an outbreak of hepatitis A, with 76 cases already reported this year, well above their annual average of 20 cases. According to the Indiana Department of Health, the viral genotype from 2 cases matches that of ongoing outbreaks in the states listed above. And similar to the other outbreaks, transmission is thought be occurring through person-to-person contact and injection drug use. Thus far, 38 hepatitis patients have been hospitalized, but there have been no reported deaths.

In the past few months, the Indiana Department of Health has taken numerous steps to help mitigate continued disease transmission. In late April, they released a clinical advisory urging those who are considered at increased risk of exposure—including homeless individuals, drug users, and men who have sex with men—to get vaccinated. The advisory recommend that healthcare providers statewide screen patients for risk factors and offer the hepatitis A vaccine to anyone in these populations. Additionally, healthcare providers in jurisdictions with ongoing outbreaks should offer the vaccine to individuals with frequent close contact with individuals who are homeless or use illicit drugs—including those who work in “homeless shelters, jails, food pantries, [or] drug rehabilitation programs.” So far, health officials have administered 5,000 vaccines to high-risk individuals. Additionally, the health department wrote letters to owners/operators of restaurants notifying them of the outbreak and reminding them of the importance of good hygiene to prevent further transmission via contaminated food. Correctional facilities have also been recommended to increase surveillance for hepatitis A, as some cases have been identified in incarcerated individuals.

Other affected states have taken similar measures to help stop the spread of hepatitis A. In San Diego, health officials administered nearly 138,000 hepatitis A vaccinations as of April 4, 2018—a coordinated effort that entailed nurses, outreach workers, law enforcement officers, and others proactively seeking out obscure locations such as alleyways and riverbeds where those at the highest risk might congregate. Other public health interventions included installing hand-washing stations and portable toilets for homeless populations to access and decontaminating city sidewalks with bleach solution. The local health emergency declaration ended in San Diego on January 23, and there have been only 11 reported cases since that date (588 total). With similar interventions, Indiana—and the other affected states—will hopefully also succeed in quelling their hepatitis A outbreak.

Outbreak Observatory aims to collect information on challenges and solutions associated with outbreak response and share it broadly to allow others to learn from these experiences in order to improve global outbreak response capabilities.

Photo: Indianapolis, Indiana. Courtesy of Pixabay.