COVID-19 Is Spreading Again as a Summer Wave Grows Across the U.S.
Learn how COVID-19 is spreading across the U.S., what is driving the summer wave, and how health officials are tracking it.
As the summer months progress, COVID-19 is once again gaining a foothold across the United States, according to the latest data from the Centers for Disease Control and Prevention (CDC). With infections proliferating or likely proliferating in all 50 states as of August 12, 2026, the virus has joined a roster of health concerns that includes measles outbreaks, Ebola cases, and foodborne illnesses linked to jalapeños.
The CDC's weekly summary underscores heightened activity in the South and West regions, while infections are also climbing in the Northeast and Midwest. Though activity remains relatively low in several areas, the overall trend points to an upward trajectory nationwide. Although many locales still report low levels of transmission, this upward trajectory is evident across the nation.
This summer's COVID-19 resurgence aligns with a June 2026 CDC projection that warned of increased transmission in Southern and Western areas that had seen comparatively little of the virus during the 2025-2026 winter. The CDC reasons that these regions may now possess less immunity from prior infections. The Northeast and Midwest, which experienced more winter activity, are projected to witness smaller summer increases.
However, the underlying reasons behind this pattern remain uncertain. COVID-19 waves can emerge during any season, and the timing often varies between regions. Scientists are actively investigating how waning immunity, new virus variants, human behavior, and environmental factors interact to influence each wave.
The CDC derives its state-level estimates from emergency department data and models transmission changes from one week to the next. One crucial metric is R(t), which approximates the average number of new infections generated by each infected individual. In addition, wastewater testing provides an early warning signal. Laboratories can identify viral particles released by both symptomatic and asymptomatic individuals, sometimes detecting the virus before an increase in cases becomes apparent in clinical settings.
While wastewater data indicates a community's growing viral presence, it does not accurately quantify the number of infections.
Traditional case counts have become increasingly unreliable due to the widespread use of at-home tests, whose results are frequently unreported. To address this gap, the CDC draws on emergency department visits, lab results, hospital data, and wastewater information. Transmission rates and severe outcomes are not rising at the same rate.
According to the CDC, national hospitalization peaks have diminished since the 2023-2024 winter. Several factors may contribute to this decline, such as broader population immunity, the absence of a dominant virus variant with significant immune evasion, and potentially lower disease severity.
Despite these improvements, a negative home antigen test result may still miss an infection in its early stages. The FDA advises individuals with symptoms to test again 48 hours later. Those without symptoms should conduct three tests, spacing them 48 hours apart. People at higher risk should seek medical attention promptly upon symptom onset, as Paxlovid must be initiated within five days, and remdesivir within seven, per CDC guidelines.
Additionally, the FDA has approved Xocova (ensitrelvir) for post-exposure COVID-19 prevention in individuals aged 12 and older when administered within 72 hours of exposure.
The CDC advises individuals with respiratory illnesses to remain home until their symptoms improve for at least 24 hours and any fever has subsided without medication. The agency also recommends additional precautions for an additional five days. While variant estimates lag behind transmission models, the CDC's latest projection indicates that XFG.1.1 accounted for 29.7 percent of circulating variants over the two weeks ending July 4, 2026.
The FDA has selected an XFG strain for incorporation into the 2026-2027 vaccine, set to be administered starting this fall. Despite growing transmission, older adults and other high-risk individuals remain particularly vulnerable to severe outcomes. However, even with declining hospitalization peaks, not every infection poses a negligible risk. This report offers information only and should not be considered medical advice.
Written by urgent.news from Discover Magazine's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
