Three Jewish day schools in New York were closed on Tuesday after a Jewish man in his 50s was taken to hospital suffering from coronavirus.
New York Mayor Bill de Blasio said the patient was “in a serious condition”.
The schools, one of which was attended by one of the man’s sons, were closed for the day as a precaution.
According to Yeshiva World News, the son had no symptoms, but his brother, a student at New York’s Yeshiva University, has been showing symptoms associated with the illness.
In addition, the Young Israel synagogue of New Rochelle in Westchester County, where the man lives, has been told not to hold services by the local health commissioner.
People who attended the synagogue on February 22 or for a funeral or a barmitzvah the following day have been asked to self-isolate until Sunday “at the very earliest”.
The man reportedly travelled to Miami and Israeli in recent months though not, it is believed, within the past fortnight.
The website gave his Hebrew name - for the purpose of saying prayers for his recovery - as Eliezer Yitzchok ben Shifra.