Public Health Northamptonshire revealed on Thursday night (December 2) that two people had tested positive with the mutant strain of the virus.
Director Lucy Wightman said: "The UK Health Security Agency are leading an investigation into these two confirmed cases in south Northamptonshire and we are working closely with them to ensure that all appropriate actions to identify close contacts are taken."
Both those who tested positive and their close contacts are self-isolating in line with Government guidelines and targeted testing will be rolled out to identify any more people who may have been at risk of picking up the virus.
Mrs Wightman added: "The aim is to understand whether any spread of the new variant within the local community may have occurred and limit the opportunity for any further infection.
“While investigations are underway it’s even more important that all Northamptonshire residents follow Covid-safe behaviours to reduce the risk of infection.
“If meeting inside now its colder, open windows as Covid-19 transmits mostly between people at close range through inhalation.
“Continue to take lateral flow tests at least twice a week, especially before going out or meeting with others.
“It’s also important to stay at home if you're not feeling well. If you have ANY Covid-19 symptoms, however mild, get a PCR test.
“Wearing a face covering in all crowded areas is advisable and now mandatory in shops and on public transport.
“Regular and thorough hand washing or hand sanitisation remains an essential part of good hygiene and prevents the spread of many viruses. As well as COVID-19 it can also reduce the spread of colds, flu and stomach bugs."
The UK's first Omicron cases were only confirmed six days ago but scientists who have analysed the variant say they are worried by what they see with signs it could be more infectious, cause more serious illness and is better at evading vaccines than other variants.
Research is still going on and nothing is certain, although the World Health Organization today (Friday) warned that all countries should prepare for potential surges of Covid.
Government figures showed more than 3,900 people tested positive in Northamptonshire during the last seven days while NHS England confirmed 49 Covid patients sadly died in the county's two main hospitals during November.
Around 90 patients were being treated for the virus in Northampton General and Kettering General hospitals when latest figures were collated on Tuesday (November 30), although the figure had risen over 100 before a spate of deaths late last week.
Plans to speed up delivery of booster jabs are due to be spelt out by the NHS in the next few days.
In Northamptonshire, more than 30,000 booster doses were delivered in the last week which officials described as 'encouraging'.
Mrs Wightman added: “Vaccination provides powerful protection against severe illness with Covid-19, so getting the jab is still the most important thing you can do to protect yourself.
"There is enough vaccine locally for everyone and we are happy to vaccinate those who have not yet had their first or second dose, as well as support people to access their booster jab."