Lewisham is not hitting many immunisation targets, with a “way to go” before the borough has protection from highly-contagious viruses like measles.

And changes in the way immunisation data is shared between health services has “hindered” work to target the groups not getting vaccinated.

Herd immunity works when a high percentage of the population is immune to a disease, stopping the spread.

It also protects people who can’t get vaccinated because they’re too ill or because they’re having treatment that damages their immune system.

There was a measles outbreak last year, with 913 cases of the virus reported across the country between January and October.

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To achieve herd immunity for measles at least 90 to 95 per cent of the population needs to be vaccinated.

Lewisham saw an improvement in the number of children getting the MMR vaccine against measles, mumps, and rubella.

But there was a “way to go to get herd immunity” Lewisham Council health and wellbeing population intelligence manager, Patricia Duffy, said.

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Speaking at a health and wellbeing board, she said: “Certain groups are at a greater risk of not being immunised, including BME [black and minority ethnic] children.”

But there were also “glaring gaps” in the data, executive director for community services Aileen Buckton said. 

This was because of changes in how information was collected from GPs.

“We are going to have to do some detailed work to start to identify which categories we should be looking at,” she added.

Lewisham clinical commissioning group chair Dr Faruk Majid said “more sophisticated data” was needed “to target people in a way that has impact.”

Work to access the data on immunisations was “in progress”, according to Lewisham Council documents.

“However current difficulty accessing this level of data hinders understanding and reactivity.

“There is a continued need to enhance information systems to allow live feedback,” the  documents explain.