All four key indicators of SARS-CoV-2 in the United States have increased, suggesting the early stages of a new wave of the pandemic
In July 2023, according to data from the Centers for Disease Control and Prevention (CDC) in the United States, four key indicators including monitoring of SARS-CoV-2 virus concentration in wastewater samples, COVID-19 positivity rate, emergency department visits, and hospitalizations have all increased. The first two indicators have shown a continuous increase for 4-6 weeks. This suggests a reversal in the improving trend of the COVID-19 situation in the United States since 2023. Recently, major media outlets in the United States have also started to pay renewed attention to the COVID-19 situation, and there is a general consensus that the country is in the early stages of a new wave of the pandemic.

All four key indicators have increased

The concentration of SARS-CoV-2 virus in wastewater samples is a highly objective monitoring indicator. The latest updated data shows an increase in the SARS-CoV-2 virus concentration in wastewater samples across the four major regions of the United States, with the most significant increases observed in the Northeast and Southeast [1]. According to the latest data from Biobot, an epidemiological wastewater company in Cambridge, Massachusetts, the concentration of the SARS-CoV-2 virus in wastewater nationwide increased by 17% compared to the previous week as of July 26th [2]. However, despite the sustained increase in relative values of the COVID-19 virus in wastewater over the past six weeks, it's important to note that the absolute values of the virus concentration in wastewater remain low compared to the peak of the COVID-19 pandemic, as the situation has been improving since 2023.

Data from the Centers for Disease Control and Prevention (CDC) website shows a significant increase in the COVID-19 testing positivity rate in the United States. Over the past five weeks, the positivity rate for COVID-19 testing in the country has increased from 4.1% to 7.6%, representing an 85% rise. [3].

The next areas to see an increase are the number of diagnosed cases and hospitalizations. The number of COVID-19 cases seeking emergency care in the United States has increased by 17.4% compared to the previous week. COVID-19 caused by XBB typically has a 3-day incubation period and worsens around 5 days, so changes in hospitalizations may occur slightly later. According to a report from the CDC, hospitalizations due to COVID-19 have increased by 10.4% in the United States compared to the previous week[4]. However, currently, the latest COVID-19 hospitalizations predominantly involve older age groups, such as individuals in their 70s, 80s, and 90s[5].

For the general public, is there anything to worry about?

First and foremost, it is important to note that despite the recent increase in key indicators of COVID-19 cases in the United States over the past few weeks, it is still relatively low compared to the earlier peak of the pandemic. In absolute terms, the current situation in the United States remains at a relatively low level since the pandemic began.

Secondly, the majority of the population has now been vaccinated or has already been infected with the virus. Therefore, overall, younger individuals do not need to be overly concerned. However, elderly individuals or those with weakened immune systems still need to remain vigilant, and it is crucial for them to consider getting timely vaccine booster shots.

For our people in China, as of July 31, 2023, the Integrated Group of the Joint Prevention and Control Mechanism of the State Council in response to the COVID-19 stated in the "Implementation Plan for COVID-19 Vaccination for Priority Groups in the Near Future" that during the prevalence of the XBB variant strain of the COVID-19 virus, with a focus on the upcoming autumn and winter seasons, priority is given to recommending the vaccination with vaccines containing the XBB variant antigen components. Individuals aged 60 and above who have completed their primary immunization or have been infected with the COVID-19 virus, as well as individuals aged 18-59 with underlying health conditions, weakened immune systems, or at high risk of infection, are eligible to receive a single dose of the vaccine containing XBB variant antigen components, either 3-6 months after the most recent vaccination or 6 months after the most recent infection (whichever is more recent).

Source: Synthesized from the National Health Commission, US CDC, Hanson Clinical Research