Now officials are getting the word out for parents to be careful who performs the tradition.
It is a sacred and celebrated Jewish tradition: the circumcision, or bris, of newborn boys.
But among some Orthodox and Hasidic Jews, there is a controversial element: a mohel uses his mouth to suction blood from the wound.
And it's once again the talk of the town in heavily Orthodox communities like Monsey.
The Brooklyn district attorney is investigating the death of an infant at Maimonedes Hospital.
The 2-week old died last fall after contracting herpes during the ritual which is called Metzitzah b'peh.
Health officials warn the virus can be transmitted during direct oral contact.
Controversy over Metzitzah b'peh erupted almost a decade ago after three newborns contracted herpes.
The state Health Department barred Rabbi Yitzchok Fischer of Monsey from perfoming such procedures, but there is no official regulation regarding the practice.
At the time, other mohels told Eyewitness News there are safer ways to perform a bris.
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