The strain (adenovirus #7) is affecting medically-fragile children with severely compromised immune systems, the department said.
"I am heartbroken by the news that several children have lost their lives in an adenovirus outbreak at the Wanaque Center for Nursing and Rehabilitation, and pray for the full recovery of the other children impacted", Murphy said.
The Department of Health today is confirming 18 cases of adenovirus among pediatric residents at the Wanaque Center for Nursing and Rehabilitation in Haskell.
Adenoviruses can cause a wide range of illnesses such as common cold, sore throat, bronchitis, pneumonia, diarrhea, pink eye, fever, bladder inflammation or infection, stomach and intestine inflammation, and neurologic disease, according to the CDC.
"This is an ongoing outbreak investigation", the department said in its statement.
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In January, two pupils in the city of Perm near the Ural mountains attacked a teacher and her fourth-grade class with knives. The blast happened at around noon at the school, which is located on a peninsula between the Sea of Above and the Black Sea.
The department had reportedly been notified by the 227-bed facility of cases of respiratory illness on October 9.
Adenoviruses typically cause "mild illness" but the children affected are "medically fragile", officials say.
Adenoviruses are a type of virus usually spread through close contact (like touching an infected surface or shaking hands), coughing, and sneezing, according to the Centers for Disease Control (CDC). They also note this strain has been particularly associated with disease in communal living facilities.
The health facility in Haskell is privately owned. A team at the facility on Sunday found minor handwashing deficiencies.
An inspection team from the state health department responded to the facility on Sunday and another team from the agency returned to the center on Tuesday.