Several states in the western US are experiencing a surge in new Covid-19 infections, according to the latest data from the Centers for Disease Control and Prevention (CDC). An update released on Friday shows Covid-19 activity in wastewater has risen to a “moderate” level nationwide, up from “low” the week before. The highest levels are in the western US, including in states such as Alaska, California, Colorado, Nevada and Utah, all of which are marked as “high”.
Wastewater monitoring is used as an early detection tool for potential future upticks. According to the California Department of Public Health’s own wastewater tracking, statewide infection numbers have now surpassed winter highs. Other metrics also show increases: as of Tuesday, the CDC estimates Covid-19 infections are growing or probably growing in 45 states, up from 40 last week.
A new Covid-19 variant, XFG or “Stratus”, is on the rise in the US, becoming the third-most common strain of the summer. First detected in south-east Asia in January, it was barely detected in the US until May. By late June, it was estimated to account for up to 14% of cases, according to the CDC.
During a CBS interview in July, physician Jon LaPook noted that this type of rise is typical for summer, with deaths and hospitalisations gradually decreasing each season. However, experts caution it is too soon to know how big the developing late-summer wave could get. Varied immune responses from prior infections and vaccinations make it difficult to predict severity, and risks are further compounded by new vaccine restrictions from the Trump administration.
The rise in cases comes as the US Department of Health and Human Services announced on Tuesday it will terminate 22 federal contracts for mRNA-based vaccines, raising questions about the safety of a technology credited with helping end the pandemic. The CDC did not immediately respond to a request for comment.
