The number of confirmed hepatitis A infections has surged to 533 cases, including six deaths, in New Jersey in the last 11 months as health officials issued a new alert that a ShopRite deli worker could have exposed people to the highly-infectious disease over an 18-day span last month.

The outbreak that began Dec. 1 and includes cases in all 21 New Jersey counties has infectious disease specialists increasingly concerned. New Jersey had just 66 hepatitis A cases in the same time period the previous year.

“This has become a public heath issue for the state," said Dr. Nikolaos Pyrsopoulos, the director of gastroenterology and hepatology at Rutgers New Jersey Medical School. “We need to raise awareness in the state that this exists and help people take steps to prevent it from happening."

The New Jersey Department of Health says 332 people have required hospitalization among the 396 cases for which officials have data.

“In my experience that’s the most I’ve ever seen have to be hospitalized," Pyrsopoulos said.

Hepatitis A cases considered part of the New Jersey outbreak since Dec. 1, 2018.N.J. Department of Health

The total number of cases is also far above typical amounts in recent years. From 2013 to 2017, there were never more than 74 total cases in New Jersey in a single year, according to the U.S. Center for Disease Control.

The homeless, drug users, homosexual men and prisoners usually account for a significant share of those sickened, state health officials said.

But the possible exposure at the ShopRite in Somerville reported Monday by Somerset County health officials and another prominent case involving an infected food handler at Mendham Golf & Tennis Club have created broader concerns. In addition, a worker was diagnosed over the summer with hepatitis A at Camp Somers, which is on the 1,000-acre Mount Allamuchy Scout Reservation in Stanhope.

The Mendham Golf & Tennis Club exposure led to one death among the 27 people who contracted hepatitis A, likely between June 9 and 30.

The Somerville ShopRite deli worker infected with hepatitis A was contagious between Oct. 13 and Oct. 30. Anyone who bought food from the deli should throw it away, according to a joint statement the New Jersey and Somerset County health departments.

Anyone who ate products the store’s deli or used the store’s bathrooms between those dates and was not previously vaccinated against hepatitis A should consider getting a vaccine as soon as possible, but no later than two weeks after eating food from the deli, the statement said. For most people, the latest date would be Nov. 13.

Health care providers have been directed to help vaccinate those most at risk for infection to stop the outbreak.

Hepatitis A is a highly contagious disease involving an inflammation of the liver. Unlike hepatitis B and C, which are blood-born diseases, hepatitis A usually spreads when a person unknowingly ingests the virus from objects, food, or drinks contaminated by small, undetected amounts of stool from an infected person.

The best and easiest way to prevent spreading the disease is for people to throughly wash their hands after using the bathroom, Pyrsopoulos said.

“It is preventable so it’s imperative that people wash and clean their hands well," Pyrsopoulos said.

A vaccine that can prevent hepatitis A is 95 percent effective and lasts about 11 years, according to Pyrsopoulos.

Most people who gets hepatitis A recover in a few weeks, according to the Centers for Disease Control and Prevention. In severe cases, illness can last longer — upwards of around a few months and in rare cases, the virus can kill.

Jeff Goldman may be reached at jeff_goldman@njadvancemedia.com. Follow him on Twitter @JeffSGoldman. Find NJ.com on Facebook.

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