Experts investigating an outbreak of a deadly infection in Essex say it is not linked to two earlier cases identified in the south of the county.

East Anglian Daily Times: Twelve people have died from an outbreak of a killer infection in Essex Picture: ARCHANTTwelve people have died from an outbreak of a killer infection in Essex Picture: ARCHANT (Image: Eastern Daily Press � 2003)

Last week, bosses at the Mid Essex clinical commissioning group said the total number of deaths from an outbreak of the rare invasive Group A Streptococcus (iGAS) infection in Maldon, Braintree and Chelmsford had risen to 13 - but this afternoon, that number was brought back down to 12.

DNA analysis has determined that two cases of iGAS in Basildon and Southend are not part of the mid Essex outbreak, experts said.

The total number of patients affected is now 32, they added.

"As part of the investigation, Public Health England has undertaken Whole Genome Sequencing of the GAS bacteria found in patients within the outbreak," a spokesman for the CCG said in an update this afternoon.

East Anglian Daily Times: Dr Anna Davey, of the Mid Essex clinical commissioning group, delivered an update on the Strep A deaths this week Picture: MID ESSEX CCGDr Anna Davey, of the Mid Essex clinical commissioning group, delivered an update on the Strep A deaths this week Picture: MID ESSEX CCG (Image: MID ESSEX CCG)

"This work has demonstrated that the iGAS case in Basildon in 2018 and the iGAS case in Southend in February 2019 are not part of the outbreak in mid Essex. Therefore, the rest of the cases are linked to the iGAS outbreak in mid Essex. The total number of patients affected is now 32 and sadly, 12 of those patients have died.

"Of the 32 patients affected by the iGAS outbreak in mid Essex, 30 are confirmed cases and two are probable."

What is iGAS?

This rare kind of bacteria can be found in the throat and on the skin and will not cause any illness for most people.

Most infections can cause mild illnesses such as a sore throat, also known as strep throat, scarlet fever or a skin infection.

For most healthy people, this will cause no more than a mild illness.

However, on rare occasions, Group A streptococcus bacteria can enter the body and cause severe, and sometimes life-threatening conditions.

While it is rare, it is not new and has been seen in the UK before, said Dr Anna Davey, chair of the CCG's board.

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How are experts testing for the infection?

Whole Genome Sequencing is used within a Public Health laboratory setting to investigate differences and similarities in the DNA sequence of bacteria.

This method allows PHE to check which iGAS cases are genetically linked and which are not.

This is done by analysing the DNA sequence of each bacterial sample collected from patients within this outbreak.

Any further information from the Whole Genome Sequencing work will be shared in future updates by the CCG, bosses said.

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