New York, Sep 2 : Rates of severe Covid disease may be staying at relatively low levels in the US, but experts agree that there are probably more infections than the current surveillance systems can capture, reports CNN. Virus levels in the US have been on the rise for weeks and federal data suggests that the current increases have stayed far below earlier peaks and notable surges. 'But judging by word of mouth among family, friends and coworkers, it can seem like everyone knows someone who's sick with Covid-19 right now,' the report noted. 'There is more transmission out there than what the surveillance data indicates,' said Janet Hamilton, executive director of the Council of State and Territorial Epidemiologists. 'We should be paying attention to it, because we are starting to see an increase.' Ali Mokdad, professor of health metrics sciences and chief strategy officer of population health at the University of Washington, said he has been getting lots of calls and questions about Covid-19 recently -- similar to what he experienced around the end of last year. Weekly hospital admissions have nearly doubled over the past month, including a 19 per cent bump in the most recent week, according to CDC data. However, hospitals have shifted their testing practices, balancing changing federal requirements and recommendations with local risk assessments, which makes it difficult to compare data from different points in time, the CNN report mentioned. Hospitals have eased back on testing to be more in line with guidance around other infectious diseases. 'The focus is on those who are symptomatic, have been exposed or might be around other high-risk patients,' the report said. Data from biotechnology firm Biobot Analytics shows that wastewater concentrations of the coronavirus are similar to what they were at the start of the first winter surge in 2020, the report added. The rising Covid cases have prompted some schools, hospitals and businesses to encourage, or even require, people to start masking up again. CDC Director Mandy Cohen has cautioned that Covid remains risky for people who are unvaccinated. The risk is especially high for unvaccinated individuals who haven't been infected before and those who are older or have underlying health conditions. The health officials are watching two new variants -- Omicron variant EG.5 (Eris) which is dominant in the US and BA.2.86 which is starting to spread. The World Health Organization (WHO) has designated EG.5 or Eris as a "variant of interest" as cases rise globally. /IANS