Illinois health officials advised of an uptick in respiratory illnesses on Monday as families geared up for holiday celebrations in the following days.

CHICAGO - Health officials warned that rates of respiratory illness are on the rise in Illinois in recent weeks as the holidays approach. The Illinois Department of Public Health said the state’s overall level of illness rose from "low" to "moderate,

Illinois health officials warn of a surge in respiratory illnesses and emphasize the importance of vaccines and preventative measures during the holiday season.

The Illinois Department of Public Health is cautioning residents of the increasing chance of respiratory illness after monitoring surveillance data. The state agency has moved up Illinois’ overall respiratory illness level from Low to Moderate,

Flu and COVID cases are down compared to last year, while RSV has remained at levels stubbornly similar to last year's, which were significant, said Anna Richie, clinical director for Memorial Urgent Care. "All these respiratory viruses have a very similar presentation," Richie said. "You really can't tell what you have without a test."

The Milwaukee Health Department tracks COVID-19, flu and RSV levels through public wastewater testing. Officials provided a behind-the-scenes look.

As the winter season continues, there's an increased chance of infections from COVID-19, influenza and respiratory syncytial virus. But, the U.S. Centers for Disease Control and Prevention predicted hospitalizations will be similar to or lower than last fall and winter.

Is COVID going around again? The CDC's wastewater surveillance system suggests the virus is growing in prevalence.