Close this search box.

COVID Resurgence: Wastewater Data Indicates Rising Cases in Western U.S. Ahead of Holiday Travel

As summer unfolds, an unsettling trend is emerging in the Western United States, where COVID-19, the virus that has dictated much of our lives since early 2020, is showing signs of resurgence. This uptick in cases is particularly concerning as it coincides with the onset of the busy Fourth of July holiday travel period, prompting public health officials to urge caution.

Recent updates from the Centers for Disease Control and Prevention (CDC) highlight that SARS-CoV-2, the virus responsible for COVID-19, is being detected at increasingly high levels in wastewater samples across several Western states, including Alaska, Arizona, California, and others, totaling 13 states and one territory. This data is not just a number but a crucial indicator that we may be at the cusp of another significant spread of the virus, particularly in these regions.

Understanding Wastewater Surveillance

Wastewater surveillance has emerged as a key tool in tracking the spread of infectious diseases like COVID-19. This method provides an early warning system of sorts, capturing data on the virus’s presence before it is clinically reported by individuals, which is often delayed until symptoms prompt medical consultation. Importantly, this type of monitoring can detect the virus in people who are asymptomatic, meaning they carry the virus and can spread it without showing any symptoms themselves.

What the Data Shows

The CDC’s recent report indicates that the levels of SARS-CoV-2 in wastewater have been rising steadily since May, with a notably sharper increase in the Western U.S. during the week of June 15 to June 22. This trend is mirrored by data from, a collaborative effort by scientists from Stanford and Emory University, which monitors nearly 200 sites across the nation. Their findings also indicate heightened virus activity in most of the country over the past three weeks, with the Western states experiencing some of the highest levels.

The Bigger Picture

While the current increases are concerning, the CDC has placed them in context: compared to the height of the pandemic, the overall COVID-19 activity remains relatively low. However, the organization has pointed out that other metrics, such as test positivity rates, emergency department visits, and COVID-19-associated hospitalizations among adults aged 65 and older, have also shown increases at some sites in the West. This multi-faceted rise underlines the potential for a broader resurgence of the virus, particularly as people gather for summer activities and travel.

Staying Safe During Summer Travel

With the Fourth of July around the corner, many are planning to travel or participate in large gatherings. In light of the recent data, the CDC continues to recommend that individuals, especially those in high-transmission areas like the Western states, wear well-fitting masks in crowded indoor settings. Keeping up to date with COVID-19 vaccinations and practicing good hygiene are also key strategies to mitigate the spread of the virus.

Moving Forward

The rise in COVID-19 cases as detected through wastewater monitoring serves as a reminder that the virus remains a part of our landscape. Public health officials are closely monitoring these trends to determine if this is the start of a summer surge or a temporary blip. As we navigate this uncertain time, it’s crucial for the public to stay informed, remain vigilant, and take preventive measures seriously, particularly in regions currently experiencing increases in virus activity.

As the situation evolves, the community’s response and adherence to public health guidelines will be pivotal in controlling the spread of COVID-19, ensuring that our steps toward normalcy are not reversed. Meanwhile, the CDC and other health agencies will continue to provide updates and guidance based on the latest data, helping inform and protect communities across the nation.