Kim Sampson and Samantha Mulcahy died after giving birth in two East Kent NHS Trust hospitals.
The likely source of herpes infections in two mothers was during the surgical procedures to deliver their babies, an inquest has heard.
Kim Sampson, 29, and Samantha Mulcahy, 32, died in 2018 in hospitals run by the East Kent Hospitals NHS Trust.
The same obstetrician carried out their Caesareans seven weeks apart, the inquest has heard.
A herpes specialist said the chance they had picked up the virus before being admitted was “vanishingly small”.
Ms Sampson died after giving birth at the Queen Elizabeth the Queen Mother Hospital (QEQM) in Margate, and Ms Mulcahy died at the William Harvey Hospital in Ashford.
Peter Greenhouse, a gynaecologist and venereologist with an expertise in the herpes virus, told the inquest the virus samples taken from both women were “exceptionally closely related but they were not identical”.
He told the inquest in Maidstone there were very small differences in the viral genome which showed there had been no contamination of the samples.
He said there was a very high chance there had been a common source of infection.
Mr Greenhouse said: “Unquestionably the most likely time was during the surgical procedure.”
Infection during surgery
Evidence from the post mortem, Mr Greenhouse added, indicated the herpes virus had been introduced into the abdomen rather than having spread through the body.
He said the mode of infection could have been through sweat and saliva, or the use of fingers during the surgery, but how it got into the abdomen he admitted was “pure conjecture”.
Mr Greenhouse said the wearing of gloves and masks did not remove the possibility of infection.
He said that since 2014 there had only been two such deaths – those of Ms Sampson and Ms Mulcahy – out of 6.4 million pregnancies.
The inquest continues.
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