Global Health Alert: Rising SARS-CoV-2 Activity and the Emergence of New Variants in 2025
The global health landscape is once again shifting, with the World Health Organization (WHO) reporting a notable increase in SARS-CoV-2 activity since mid-February 2025. This resurgence, accompanied by the emergence of new variants like NB.1.8.1, underscores the persistent and evolving nature of COVID-19. As we navigate 2025, understanding these global COVID trends and adapting our public health recommendations is crucial for maintaining collective well-being.
The Global Picture: A Resurgence in Activity
After a period of relatively lower circulation, global SARS-CoV-2 activity has seen a significant uptick. Data from sentinel sites indicates that the test positivity rate reached 11% as of mid-May 2025, a level not observed since July 2024. This SARS-CoV-2 activity increase 2025 is primarily concentrated in the Eastern Mediterranean, South-East Asia, and Western Pacific regions, prompting increased vigilance from health authorities worldwide. While countries in the African, European, and American regions are currently reporting lower positivity rates, continuous monitoring remains essential as the virus demonstrates a lack of clear seasonality.
Introducing NB.1.8.1: A Variant Under Monitoring
Driving much of this renewed activity is the NB.1.8.1 variant, an Omicron-descendant that has been classified as a "variant under monitoring" by both the WHO and the European Centre for Disease Prevention and Control (ECDC). This new COVID-19 variant is rapidly gaining ground globally, accounting for over 10% of infections in multiple regions, including Europe, Asia, and North America, and is particularly dominant in areas like China and Hong Kong.
Preliminary data suggest that NB.1.8.1 may exhibit increased transmissibility and a partial ability to evade certain immune defenses. Fortunately, the reported COVID-19 symptoms 2025 for NB.1.8.1 remain similar to recent Omicron variants, typically involving fatigue, fever, sore throat, and congestion, with occasional gastrointestinal issues. Crucially, there is currently no indication that this variant causes more severe illness, and existing vaccines and boosters are still expected to offer strong protection against severe disease.
What This Means for Public Health
The ongoing evolution of SARS-CoV-2, highlighted by the NB.1.8.1 variant, emphasizes the need for continuous adaptation in public health strategies.
- Vigilant Surveillance: Continued genomic surveillance is vital to track the emergence and spread of new variants, assess their characteristics, and inform timely public health responses.
- Vaccination Remains Key: Staying up-to-date with COVID-19 vaccinations and booster shots, particularly for at-risk groups, is crucial for maintaining protection against severe outcomes.
- Personal Protective Measures: Basic practices like hand hygiene, ensuring adequate ventilation in indoor spaces, and considering face masks in crowded public settings, especially for high-risk individuals, continue to be effective.
- Risk-Based Approach: The WHO advises Member States to maintain a risk-based, integrated approach to managing COVID-19, focusing on preventing severe disease and death.
Key Takeaways
- Global SARS-CoV-2 activity has risen significantly since February 2025, reaching an 11% test positivity rate by mid-May.
- The NB.1.8.1 variant, an Omicron descendant, is now a "variant under monitoring" and is spreading globally.
- NB.1.8.1 may be more transmissible and partially evade immunity, but symptoms are similar to previous Omicron strains, and severe illness is not currently linked.
- Vaccination, ongoing surveillance, and adherence to public health guidelines are crucial in managing the evolving pandemic.
The dynamic nature of SARS-CoV-2 means that vigilance and adaptability remain our strongest tools. By staying informed about WHO COVID update 2025 and adhering to recommended public health measures, communities can continue to mitigate the impact of the virus and protect vulnerable populations.