The symptoms of NB.1.8.1 are largely consistent with those of previous Omicron variants. Commonly reported symptoms include:
Sore throatFatigueMild coughFeverMuscle achesCongestion
Reportedly, in some cases, individuals have experienced persistent low-grade hyperthermia, a condition where the body temperature is elevated beyond normal due to failed thermoregulation, differing from typical fever. Other reported symptoms include headaches, nausea, loss of appetite, and gastrointestinal issues.

NB.1.8.1 has demonstrated a higher transmissibility rate compared to some earlier variants. Preliminary data suggest that this variant has an enhanced ability to bind to human cells, potentially leading to increased infection rates. The variant has been detected in travelers arriving at major U.S. airports, including those in California, Washington, Virginia, and New York. Its spread underscores the importance of continued surveillance and public health measures.