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A software error meant that eight local authorities did not have access to the full data on positive test results in their areas between 17 April and 17 May. These included Blackburn with Darwen, which has experienced a sharp rise in cases of the B.1.617.2 variant. The other local authorities were Blackpool, York, Southend-on-Sea, Thurrock, Bristol, North Somerset and Bath, and North East Somerset.
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