A large and sudden increase in cases of influenza among students on the University of Michigan-Ann Arbor campus will be the focus of federal health experts seeking to learn more about how the flu is spreading and vaccine effectiveness as the nation heads into the flu season.

The work—which begins this week—is being led by the Washtenaw County Health Department, Michigan Department of Health and Human Services and the university with a team from the Centers for Disease Control and Prevention.

Since the first positive case on Oct. 6, there have been 528 cases of influenza diagnosed at the University Health Service with 77% of cases in unvaccinated individuals. UHS officials saw increases in cases of influenza the past two weeks, with 313 cases (37% test positivity) the week of Nov. 8 and 198 cases (27% test positivity) the previous week.

“Through prompt detection and collaboration with county and state health officials, as well as School of Public Health and Michigan Medicine researchers, we quickly identified these cases as influenza A(H3N2) virus infections,” said Lindsey Mortenson, UHS medical director and acting executive director.
“Partnering with the CDC will accelerate our understanding of how this flu season may unfold regionally and nationally in the setting of the COVID-19 pandemic.”

The timing of the increase in cases comes as many U-M students prepare to depart from campus to destinations across the country and globe as individuals return to their permanent residences for the Thanksgiving break.

Officials are calling on the entire community to get vaccinated against influenza as soon as possible. Vaccination can protect against severe illness, hospitalization and death due to flu, as well as reduce the overall spread of illness.

Vaccinated individuals also help protect people around them, including those who are more vulnerable to serious flu illness, like babies and young children, older people and people with certain chronic health conditions.

“While we often start to see some flu activity now, the size of this outbreak is unusual,” said Juan Luis Marquez, medical director at the Washtenaw County Health Department. “We’re grateful for the additional support of the CDC and our ongoing partnership with the university as we look more closely at the situation.

“This outbreak doesn’t necessarily have an immediate impact on the broader local community, but it does raise concerns about what the flu season may bring. Most importantly, we strongly recommend anyone not yet vaccinated against seasonal flu to do so. And anyone at higher risk of severe flu complications should talk to their doctor about prescription antiviral medications at the first sign of flu symptoms.”

The opportunity to learn more about influenza on campus is made possible through a request by the CDC and the MDHHS for Epidemiologic Assistance (Epi-Aid), which is an investigation of an urgent public health problem, such as infectious or noncommunicable disease outbreaks, unexplained illnesses, or natural or human-caused disasters.

When a public health authority requests assistance from the CDC, an Epi-Aid allows rapid, short-term (1-3 weeks), generally onsite, technical assistance by Epidemic Intelligence Service officers and other CDC subject matter experts. The focus of an Epi-Aid investigation is to collaborate with partners to make rapid, practical decisions for actions to prevent and better understand the public health concern.

The objectives of the CDC team will be evaluating flu vaccine uptake and vaccine effectiveness and risk factors for spread through data analysis, questionnaires and sample collection (respiratory specimens or serology) of patients at UHS.

The work of the team is also important due to potential risks associated with co-infection with flu and COVID-19, low levels of flu activity last season, and because current data from the state shows Michiganders are further behind with getting their flu vaccine than in prior years.

Officials remind the community that many of the same tools used to prevent the spread of COVID-19 also help prevent the spread of flu. In addition to wearing a mask and getting vaccinated, it is important to stay home if sick, cover coughs and sneezes, and wash hands frequently.

Vaccination opportunities: Kroger Health Vaccine Clinic will offer 600 available slots to the U-M community as well as the broader local community 9 a.m.-3:30 p.m. Tuesday, Nov 16, at 1310 North University Court Building. Insurance will be billed. Registration

Flu vaccination is widely available from local health care providers and pharmacies. Currently, the Washtenaw County Health Department can offer flu vaccines if individuals are also receiving a COVID-19 vaccination. Other local options and local flu activity can be found at www.washtenaw.org/flu or by using the flu vaccine locator.