COVID-19 cases and hospitalizations are increasing again, suggesting it may have become a summer illness.

COVID-19 cases and hospitalizations are increasing again, suggesting it may have become a summer illness.

COVID Wastewater Levels

Nationally, COVID wastewater levels are similar to that of every pandemic summer except for 2022, when the world saw a spike due to the Omicron variant BA.5. The U.S. Center for Disease Control and Prevention’s data tracker shows a 10.3% rise in hospitalizations from July 9-15, the most recent period for which data is available. Deaths, however, are holding steady.

According to Dr. Michael Chang, a pediatric infectious disease specialist at Children’s Memorial Hermann Hospital and UTHealth, COVID wastewater levels are on the rise in the Houston area, and positive tests in the community have been elevated since late June. Despite this, there hasn’t been a significant increase in kids admitted to his hospital for COVID. However, other hospitals in the city have reported increased pediatric hospitalizations, and adult hospitals have seen a rise in COVID hospitalizations since the end of June.

The southern region of the U.S., including Texas, is experiencing a steady upward trend in COVID cases, according to BioBot Analytics. The Northeast also has a steady upward trend, while the West and Midwest show sharper increases, although the levels in these regions still lag behind the rest of the country.

So, what are the reasons behind the rise in COVID cases this summer? Dr. Chang suggests that increased indoor activities due to the heat and people seeking air conditioning play a significant role. Similar to winter spikes caused by increased indoor activities driven by cold and people seeking heat, summer travel is likely contributing to the rise in cases as well. Another factor is the waning immunity. Antibody immunity from both infection and vaccination lasts roughly three to six months. Those who were infected last winter are likely more susceptible to the virus again.

While new COVID boosters are expected this fall, Raj Rajnarayanan, an assistant dean of research at the New York Institute of Technology campus in Jonesboro, Ark., and a top COVID-variant tracker, believes that the XBB.1.5 variant known as “Kraken” that rapidly grew last winter will be on its way out by the time the booster hits the market. Although the new boosters should still be useful, Rajnarayanan highlights the challenge of how well they will hold up against the new variants that may emerge by the time they are rolled out.

Regarding the seasonality of COVID, it is commonly observed that respiratory viruses tend to spike in the winter. However, Dr. Chang cautions against drawing a definitive conclusion about COVID becoming a summer trend. While the properties of the virus can influence seasonality, human behavior also plays a significant role. For instance, the rise in cases due to people abandoning COVID mitigation strategies such as masking and distancing is not solely dictated by viral properties. Dr. Chang does acknowledge that people’s COVID-related behavior has stabilized in the last two summers, but the extent of this summer’s wave will provide a better answer as to whether summer spikes will be an ongoing occurrence.

In conclusion, the rise in COVID cases this summer can be attributed to factors such as increased indoor activities driven by the heat, summer travel, and waning immunity. However, it is important to consider the influence of human behavior in shaping the course of the pandemic. While the impact of the new COVID boosters is promising, the emergence of new variants remains a concern. Only time will tell if summer spikes in COVID cases will become a regular occurrence.