A new COVID-19 variant, designated NB.1.8.1, has been detected in the United States. This variant has been linked to a recent increase in cases in China and Hong Kong. The Centers for Disease Control and Prevention (CDC) has confirmed its presence. However, current US case numbers are low.
CDC Confirms NB.1.8.1 Presence
The CDC has identified multiple instances of the NB.1.8.1 variant. A CDC spokesperson confirmed these findings to Fox News Digital. Despite these detections, the number of confirmed cases remains small. There are currently fewer than 20 sequences of NB.1.8.1 in the US baseline surveillance data.
Tracking Threshold Not Yet Met
Due to the low number of cases, NB.1.8.1 has not yet met the threshold for inclusion. It is not currently featured on the CDC’s official COVID Data Tracker dashboard. The CDC continuously monitors all SARS-CoV-2 sequences. If this variant increases in proportion, it will be added to the public dashboard. This ensures transparency in tracking dominant strains.
Detection Methods
Reports from CBS News suggest the cases were detected through the CDC’s airport screening program. However, the CDC spokesperson did not explicitly confirm this detail to Fox News Digital. Traveler-based genomic surveillance and wastewater testing are common methods for early variant detection. This helps monitor global circulation of communicable diseases.
Current COVID-19 Landscape in the US
Despite the emergence of NB.1.8.1, the overall situation regarding respiratory illnesses in the US remains stable.
Low Emergency Room Visits
The CDC reported on May 23 that emergency room visits for influenza, COVID-19, and RSV are currently “very low.” Their two-week predictions for COVID-19 and influenza suggest these low levels will likely continue. This indicates a general period of reduced respiratory virus activity.
Wastewater Surveillance Data
A CDC map utilizes wastewater (sewage) testing data to show viral activity. This map indicates that most US states are experiencing either low or very low levels of the virus. Wastewater surveillance is an effective tool for tracking community viral loads. As of the latest data, South Dakota is the only state showing a high level of viral activity.
International Context and Variant Severity
The NB.1.8.1 variant’s appearance in the US follows its link to surges in Asia.
Surge in China and Hong Kong
The COVID-19 NB.1.8.1 variant has been associated with a significant increase in cases in China and Hong Kong. It is a descendant of the Omicron sublineage JN.1, and some preliminary data suggests it may have increased transmissibility. This means it might spread more easily than some earlier variants.
Hong Kong’s Public Health Advice
Earlier this month, Hong Kong authorities issued a public statement. They urged residents, especially high-risk individuals, to wear surgical masks. This recommendation aims to mitigate spread in crowded areas. Importantly, the statement also noted that there is no current evidence to suggest NB.1.8.1 causes more severe illness than other circulating COVID-19 variants. Symptoms reported for NB.1.8.1 are largely consistent with previous Omicron strains, including sore throat, fatigue, mild cough, fever, muscle aches, and congestion.
Ongoing Monitoring and Precautions
The detection of the NB.1.8.1 variant highlights the ongoing evolution of SARS-CoV-2. The CDC continues to monitor all new variants closely. While case numbers are currently low in the US and there’s no evidence of increased severity, public health vigilance remains important. Staying informed and following general health guidelines are key.
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