Global COVID-19 Enters Endemic Phase as Mild Winter Uptick Prompts Renewed Vaccination Efforts

As the Northern Hemisphere moves deeper into winter, a modest resurgence of COVID-19 driven by SARS-CoV-2 subvariants KP.3, KP.2, and the FLiRT lineage (descendants of JN.1) is being observed worldwide. The World Health Organization (WHO) reports that weekly global COVID-19 deaths have fallen to fewer than 3,000—dramatically down from over 100,000 per week during the pandemic’s peak in 2020—signaling a transition to a “low-level endemic phase.”

According to WHO, these Omicron-derived subvariants exhibit enhanced immune evasion but have not shown increased disease severity. Since October 2025, countries including the United States, the United Kingdom, Germany, Japan, South Korea, and China have reported mild increases in cases, coinciding with the typical seasonal rise in respiratory illnesses such as influenza and respiratory syncytial virus (RSV), creating a so-called “tripledemic” pressure on health systems.

In response, multiple nations launched updated vaccination campaigns this autumn. Newly authorized vaccines targeting KP.2/JN.1—including mRNA boosters from Pfizer and Moderna, as well as protein-based vaccines from Novavax and China’s Zhifei Biological—have been rolled out across the European Union, the U.S., Canada, Japan, China, and other regions. These updated shots primarily prioritize adults aged 65 and older, individuals with underlying health conditions, and immunocompromised populations.

Notably, in March 2025, WHO officially recommended integrating COVID-19 vaccination into routine adult immunization programs—a strategic shift reflecting the global move from emergency pandemic response to long-term disease management.

Public health experts stress that while the acute threat of the pandemic has subsided, regular booster doses with updated formulations remain critical for vulnerable groups. They also advise maintaining basic respiratory hygiene, especially during winter months.

WHO continues to urge countries to sustain genomic surveillance, case monitoring, and healthcare capacity to ensure rapid readiness in the face of ongoing viral evolution.