Omicron is on the cusp of becoming the North East Lincolnshire’s dominant coronavirus strain.
Public health officials have warned that the number of cases are doubling approximately every three days.
208 probable cases were discovered between December 8 and 18.
The area’s overall infection rate has remained steady despite a surge in the rest of the country.
However, the new strain is so transmissible that cases are expected to rise in future, according to North East Lincolnshire Council’s latest epidemiology report.
The latest infection rate for the area is 448 cases per 100,000 – down from 592 the week before.
Covid infection rates in the borough are now highest in young people, particularly primary school children.
The Omicron strain was first found in the area last week.
It is spreading so quickly in parts of the country that the government are considering new restrictions to curb it.
The council’s report says: “Omicron has progressed rapidly to become the dominant strain of Covid-19 circulating in London and the South East and even though we only had our first confirmed case in North East Lincolnshire last week it already appears to be the on the cusp of becoming the dominant strain in our area too.
“At this point there is no evidence that Omicron is producing a more severe illness than earlier variants.”
It adds: “Although there has been a decrease in the number of Delta cases in the last two weeks it is likely that there will be an increase in new infections of the Omicron variant due to the highly transmissible nature of the variant.”
2,059 new Covid cases have been confirmed since the start of December.
Humberston and New Waltham ward had the highest number of cases (73) and West Marsh Ward had the lowest (15).
Grimsby hospital is treating 11 patients with coronavirus as of Thursday morning, of which one is in intensive care.
There is only one case in a care home in North East Lincolnshire. Two care homes are closed and one is partially closed, all others remain open.
The government is carefully watching Omicron data to determine whether new restrictions should be brought in.
Although the illness is thought to be milder, there is concern that the sheer number of cases could overwhelm hospitals.
More than 100,000 cases were reported for the first time in the UK on Wednesday.