The two practices, which operate from the County Oak Medical Centre in Brighton and serve a total patient population of around 17,000, were closed along with their branch surgeries on 10 and 11 February.
While the surgeries were closed, calls to the Warmdene Surgery or the Carden Surgery were met with a recorded message directing patients towards NHS 111 that explained their premises had been forced to close due to 'an urgent operational health and safety reason'.
A Brighton GP has been named in media reports as one of two doctors understood to have contracted the coronavirus after being on holiday with a man who had become infected in Singapore.
The two reopened surgeries posted a message on their websites which reads: 'We would like to sincerely thank all patients, carers, colleagues and friends for their patience, understanding and kind words, while we have been dealing with some health and safety concerns at the medical centre.
'Please be absolutely assured that the facilities have been extensively and rigorously cleaned throughout, in accordance with public health advice. The interior of the building was also recently redecorated providing you with enhanced assurances.
'Both Warmdene and Carden surgeries would like to take this opportunity to thank all staff for their help and support to bring about a swift re-opening of the practices under difficult circumstances.
'Please note that some services may initially be affected by resource constraints as we endeavour to return all clinical and administrative services to normality over the coming one or two weeks. We hope you will understand this.'
The reopening of the two practices came a day after health and social care secretary Matt Hancock told MPs that eight cases of coronavirus had been confirmed in England.
He said all patients affected were 'receiving expert care from the NHS, which is well prepared and equipped to deal with this kind of situation'.
'Contact tracing of the first four cases has been undertaken rapidly and is now complete, while tracing for the latest four cases is ongoing,' the health and social care secretary told parliament.
'This contact tracing itself identified five of the cases – a tribute to the skill and tenacity of Public Health England staff – as well as finding a further five British nationals in France who have also tested positive for the virus.'
Mr Hancock added: The situation will get worse before it gets better. We will be guided by the science. Be in no doubt, we will do everything that is effective to tackle this virus and keep people safe.'