Covid is making a resurgence, with a new strain known as ‘Nimbus’ or NB. 1.8.1 causing unusual symptoms that could be mistaken for other illnesses. This variant has been detected in Northern Ireland and is now on the World Health Organization’s watchlist, following a surge in global cases from 2.5% in March to over 10% by late April.
The Public Health Agency has reported seven cases of this new strain in the past eight weeks. According to its latest respiratory surveillance report from June 18, Covid-19 levels increased during week 24 of 2025 (June 9 – 15), with 137 unique episodes identified compared to 108 in week 23.
The highest Covid-19 episode rate in week 24 was among the 75+ age group (33.0 per 100,000 population). Ards and North Down had the highest episode rate in week 24 (11.6 per 100,000 population). In week 24, there were 1,449 Covid-19 tests, 148 of which were positive (10.2% positivity). This is higher than week 23 (7.6% positivity), reports Belfast Live.
One Covid-19 outbreak was reported in a care home setting. Between April 14 and June 8, a total of 119 Covid-19 samples were sequenced, with 8 identified as the NB. 1.8.1 variant, accounting for 6.7% of all sequenced samples. The Public Health Agency (PHA) has indicated that due to the limited number of samples sequenced, there is a low level of confidence in the precision of this estimate, and the percentages of each variant could shift as more data becomes available.
The new strain doesn’t seem to cause more severe illness, but there are concerns it may be more transmissible, and its symptoms are surprising many, according to the Irish Mirror. Unlike previous variants which resembled a bad cold or flu, NB.1.8. 1 is associated with gastrointestinal issues such as nausea, vomiting, diarrhoea, constipation, bloating, abdominal pain, and even heartburn.
Dr Lara Herrero, an Associate Professor and Virology Research Leader at Griffith University, noted: “Common symptoms [of NB.1.8.1] include sore throat, fatigue, fever, mild cough, muscle aches and nasal congestion. Gastrointestinal symptoms may also occur in some cases.”
Covid symptoms can encompass:
The PHA continues to urge those eligible in Northern Ireland to get their spring Covid-19 vaccination before the campaign concludes at the end of June.
This year’s spring vaccine is available to:
The Covid-19 Spring 2025 vaccination drive kicked off on April 7 and is set to run until June 30. The campaign is being rolled out by a variety of providers, including GPs, community pharmacies, and Health and Social Care Trusts. As of June 8, the total number of jabs given was 67,569, with the highest uptake seen amongst care home residents (57.9%) and those aged 75 years and over (39%).