What is the public health impact of norovirus?
According to the CDC, norovirus is the leading cause of vomiting and diarrhea from acute gastroenteritis (inflammation of the stomach and intestines) among people of all ages in the United States, with an estimated 19-21 million illnesses every year. Norovirus impacts people in all age groups — it is the leading cause of foodborne illness, and a frequent cause of outbreaks in schools, daycares, long-term care facilities, and cruise ships. Currently, there are no approved vaccines for norovirus.
How do public health systems currently track norovirus?
Health departments are not currently required to report individual norovirus cases or outbreaks to the CDC. The CDC tracks norovirus outbreaks and positive clinical PCR test results from participating U.S. laboratories. The CDC receives reporting on norovirus outbreaks from states participating in the NoroSTAT program. The CDC’s Calicinet program sequences norovirus genogroups of a subset of reported outbreaks, and states participating in NoroSTAT must also submit data to Calicinet. Clinical labs that agree to send data to the CDC through the National Respiratory and Enteric Virus Surveillance System (NREVSS) contribute to analyses of national and regional patterns of PCR test positivity. BIOFIRE’s Syndromic Trends tracks aggregated diagnostic results from the clinical laboratories that participate in their program.
What data gaps exist for current norovirus tracking systems?
People infected with norovirus may be asymptomatic, and do not consistently go to the doctor if they do have symptoms. Even if they do present clinically, differences between the many viruses that can cause vomiting and diarrhea (norovirus, astrovirus, rotavirus, and others) can only be determined through clinical testing, which is not always ordered.
At a national level, the 14 states receiving NoroSTAT funding are required to submit norovirus outbreak data to the CDC within seven days of an outbreak (Alabama, Massachusetts, Michigan, Minnesota, Nebraska, New Mexico, North Carolina, Ohio, Oregon, South Carolina, Tennessee, Virginia, Wisconsin, and Wyoming). Any state can submit data to the CDC’s National Outbreak Reporting System, but these data tend to be incomplete, as states without NoroSTAT funding frequently report foodborne outbreaks only. For the CDC’s regional trends, PCR tests are reported, analyzed, and shared with the CDC weekly, but reporting delays frequently lead to incomplete data.
What lab methods do you use to analyze norovirus in wastewater?
Biobot uses a highly sensitive method called quantitative polymerase chain reaction (qPCR) to identify genetic material (single-stranded RNA) from norovirus in wastewater samples. Biobot analyzes samples of influent wastewater.