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.
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 can detect viruses spreading from one person to another within a community earlier than clinical testing and before people who are sick go to their doctor or hospital,” the CDC notes. “If you see increased wastewater viral activity levels, it might indicate that there is a higher risk of infection.”
Wastewater tracking is often used as an early detection tool for monitoring 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 are also showing increases in the illness. As of Tuesday, the CDC estimates Covid-19 infections are growing or probably growing in 45 states, which is 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. The variant was first detected in south-east Asia in January but was barely detected in the US until May. By late June, it was estimated to account for up to 14%, according to the CDC.
During a CBS interview in July, physician Jon LaPook said that this type of rise was typical for the summer.
“We now know that there’s a winter spike and then there’s a summer spike,” the outlet’s chief medical correspondent said in the interview. “And every year, the number of deaths, the number of hospitalizations, is gradually going down each season. So that’s the good news.”
Still, experts caution it is too soon to know how big the developing late-summer wave could get. While cases are rising more slowly than at the start of previous surges, varied immune responses from prior infections and vaccinations make it difficult to predict how severe illnesses could be. The risks are further compounded by new vaccine restrictions from the Trump administration.
The rise in Covid-19 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 and saving millions of lives.
The CDC did not immediately respond to a request for comment.
