The CDC's Respiratory Illnesses Data Channel resumed its weekly updates on Monday, June 22, 2026. Its first data release since the Juneteenth federal holiday delayed the normally scheduled Friday update. The national picture remains reassuring at the top line: COVID-19 activity is low in most areas of the country, seasonal influenza activity is low, and RSV is at low levels in most regions.
But the CDC's scenario modeling language — included in the same updated page — carries a specific regional warning that residents in the South and West should take seriously. "Scenario modeling indicates that regions which did not experience a substantial level of COVID-19 activity during the most recent winter months — South and West — are expected to experience increases in COVID-19 activity in the summer months," the CDC states. And separately: "It remains possible that there could be larger increases this summer, particularly if a variant that the immune system no longer recognizes becomes more common."
As of the CDC's most recent epidemic trend model update from June 16, 2026, COVID-19 infections are estimated to be growing or likely growing in 2 states, declining or likely declining in 36 states, and not changing in 11 states. The model uses real-time emergency department visit data to estimate the time-varying reproductive number (Rt) — a measure of whether infection counts are growing or shrinking in each state.
What the South and West Summer Surge Warning Actually Means
The logic behind the summer surge warning is grounded in immunological patterning rather than current case counts. During the 2025–2026 winter respiratory season, COVID-19 activity was elevated primarily in the Northeast and parts of the Midwest, meaning the populations in those regions experienced relatively higher natural infection rates during that period, building more recent immunity.
The South and West, by contrast, experienced comparatively lower winter COVID activity, which typically means the populations there have lower recent immunity going into summer. Historically, COVID-19 has shown summer surges, particularly in southern states, where indoor air conditioning drives people indoors together during July and August, creating conditions favorable to respiratory transmission. This pattern was documented in 2021, 2022, and 2023 before being disrupted by the evolving immune landscape.
The variant escape scenario is the wild card. The CDC notes on its scenario modeling page that a variant with "moderate immune-escape properties" that the immune system no longer recognizes could amplify the summer surge significantly. This is not a prediction, it is a risk scenario. The current dominant variants remain variants for which most recent vaccinees and recently infected individuals have meaningful, if partial, immune protection.
| CDC June 22, 2026 COVID-19 Respiratory Update | Data |
| National COVID-19 activity level | Very low |
| States with growing or likely growing COVID-19 | 2 |
| States with declining or likely declining COVID-19 | 36 |
| States with no change | 11 |
| Most at-risk regions for summer increases | South and West |
| Trigger for higher-than-expected wave | Immune-escape variant becoming more common |
| RSV activity level | Low nationally |
| Influenza activity | Low; flu/RSV season updates paused until fall |
| Other viruses elevated nationally | Parainfluenza (PIV), HMPV, rhinovirus/enterovirus |
What Residents in the South and West Should Do
The CDC's framing is cautious and forward-looking, not alarmist. COVID-19 at "very low" national activity does not mean the summer season is without risk, it means current disease burden is not straining healthcare systems. The summer surge warning is based on population immunity patterns, not current transmission data.
For higher-risk individuals — adults 65 and older, people who are immunocompromised, and those with chronic lung, heart, or kidney conditions — the modeling context provides a relevant signal: summer 2026 is not the time to stop thinking about COVID-19 protection. Updated COVID-19 vaccines for the 2026–2027 formula are expected to be available in late summer or early fall; people in high-risk categories should speak with their physicians about timing.
Other respiratory viruses worth tracking this summer: the CDC's June 22 update confirms that parainfluenza virus (PIV) is elevated nationally, and that both human metapneumovirus (HMPV) and rhinovirus/enterovirus (RV/EV) are elevated nationally but declining. These viruses cause croup, bronchitis, and cold-like illness, particularly in young children and older adults. They are not COVID-19, but they are circulating simultaneously and can compound the burden on the same patient populations that COVID-19 threatens.
Frequently Asked Questions
What did the CDC's June 22 COVID-19 data update show?
The CDC's Respiratory Illnesses Data Channel, updated June 22, 2026 after the Juneteenth holiday delay, confirmed that COVID-19 activity is very low nationally but growing or likely growing in 2 states. Scenario modeling specifically warns that the South and West are expected to see summer COVID-19 increases.
Why are the South and West specifically at risk for a summer COVID surge?
Those regions experienced comparatively lower COVID-19 activity during the 2025–2026 winter season, resulting in lower recent population immunity compared to the Northeast and Midwest. This creates conditions for summer spread, particularly as indoor air conditioning brings people together during the hottest months.
What is the variant escape risk the CDC mentioned?
The CDC flagged the possibility that a variant that "the immune system no longer recognizes" could drive a larger-than-expected summer surge. This is a risk scenario, not a prediction, based on the modeling framework that has tracked immune-escape variants in prior seasons.
What other respiratory viruses are circulating right now?
The CDC's June 22 update confirmed parainfluenza virus (PIV) is elevated nationally, and HMPV and rhinovirus/enterovirus remain elevated nationally but declining. These viruses can cause croup, bronchitis, and cold-like illnesses, particularly in young children.
Should high-risk people do anything differently right now?
Adults 65 and older, immunocompromised individuals, and those with chronic illness should speak with their physicians now about COVID-19 vaccine timing ahead of the fall and monitor CDC's weekly updates. COVID-19 vaccines for 2026-27 are expected in late summer. For current activity levels in your state, visit cdc.gov/respiratory-viruses.
