The New York Department of Health suspects that an outbreak of measles in the Chasidic community may have originated in London.

Twelve cases have been confirmed over the past two months, the majority of them in Williamsburg, home to around 70,000 Satmar Chasidim, and two in Borough Park, a Bobover enclave.

“We have not identified any source yet,” said Dr Jane Zucker, assistant commissioner for immunisation at New York City’s Department of Health and Mental Hygiene, “but in the past we have had measles imported from the UK and other European countries.

“There is a lot of movement between the Jewish communities in London and New York, so it certainly would not be a surprise if there were travel links.”

Although successful vaccination campaigns had eliminated local transmission of measles in the UK — as well as in the US — the Health Protection Agency announced last year that the highly contagious disease was once again endemic. There have been sporadic outbreaks of measles in Charedi areas, and an outbreak of mumps in Stamford Hill earlier this month.

Dr Joseph Spitzer, a Stamford Hill doctor, said that he had no evidence that immunisation levels were lower in the Orthodox community in Hackney than any other group, but said that they were short of getting “herd” protection, which required 95 per cent immunisation rates in a community.

He believed that the local health authority, City and Hackney Primary Care Trust, needed to do more to issue reminders when children from large families were due to receive MMR vaccinations.

“It’s hard enough to remember one’s own dates for immunisations, but when you’ve got several children you need to receive written reminders over vaccination dates.”

A representative of the Charedi Jewish Community Health Forum said: “There’s a close relationship between the New York and Stamford Hill Orthodox communities so diseases can spread fast between us. There’s no evidence that we caused the recent measles outbreak in New York.”

According to Dr Zucker, levels of immunisation amongst New York Chasidim are also low.

“Eighty per cent of cases could have been prevented if children had been properly vaccinated.”

She concedes that children are generally immunised by the time they enter school — as required by New York law — but says parents often delay vaccination until enrollment time, leaving children vulnerable for several years.

Most of the victims in the recent outbreak had not yet started school.

Rabbi David Niederman, head of Williamsburg’s United Jewish Organisation, said that the community has worked closely with schools and the department of health to prevent the spread of measles.

Most local children start school early, just after turning two, and claims about widespread resistance to vaccination in Jewish Williamsburg are “just nonsense”.

The children who got measles “were obviously not vaccinated,” he says, but delaying vaccination is “less than not the norm”.

There were more than 1,000 cases of measles in Israel between August 2007 and May 2008, many of them in Charedi areas, where vaccination is also low.

The outbreak began when a 22-year-old Satmar Chasid from London, who had the disease, attended a Jerusalem wedding along with 2,000 others.