The NB.1.8.1 variant is currently responsible for more than half of locally sequenced COVID-19 cases in Singapore, according to health authorities [1, 2, 3]. Experts have confirmed that symptoms linked to NB.1.8.1 are broadly similar to those seen in earlier waves and strains.
Associate Professor Lim Poh Lian said, "Current evidence shows that symptoms associated with NB.1.8.1 are largely similar to those seen in previous waves or earlier strains, which range from mild upper respiratory illness to severe disease such as pneumonia. Commonly reported symptoms include fever, chills, cough, sore throat, runny nose, headache, fatigue, muscle aches, and in some cases, gastrointestinal symptoms such as nausea, vomiting or diarrhoea. There is no indication that NB.1.8.1 or other currently circulating variants, are more transmissible or cause more severe disease compared to previously circulating variants" [1].
Common indicators of COVID-19 remain fever, cough, and respiratory symptoms. Some patients may also experience gastrointestinal issues or fatigue. There is no evidence that NB.1.8.1 spreads faster or leads to more severe illness than prior variants [1, 2, 3].
The Health Ministry dismissed circulating text messages falsely claiming NB.1.8.1 causes no fever and is harder to detect. Professor Paul Tambyah said the texts contained information from early in the pandemic but included some accurate points about how symptoms can vary. He said, "Some people do not have a fever with Covid-19. We have known that for six years. We have also known that the symptoms can include sore throat, loss of taste, body aches and gastrointestinal symptoms as well as dizziness especially on standing up even some time after recovering from SARS CoV2 infection" [1].
Singapore experienced a 59% rise in COVID-19 cases during the week before August 19, reaching 12,700 infections and increased hospitalisations [1, 2, 3]. Authorities continue to urge at-risk groups to get annual booster shots, noting vaccines remain effective against NB.1.8.1 [1, 2, 3].
