DuPage County reported three human cases of the mosquito-transmitted West Nile virus in the last two weeks — including the county’s first human case of 2016 — prompting the DuPage County Health Department to issue a level three, or “high,” risk level for residents.

On Friday, Aug. 26, health department officials said that an 80-year-old woman was diagnosed with the virus in Darian, a town about 16 miles south-west of Wheaton’s campus. Three days later, on Aug 29., two more cases, both occurring in females in their 40’s, were reported in Naperville and Warrenville.

In response to the cases, DCHD updated its online “Personal Protection Index” widget to reflect a level three risk on the zero-to-three scale. Britt Black, director of Student Health Services at Wheaton, explained that “this number represents the level of protection an individual should use due to the life of a mosquito, weather factors and positive cases in the county.” The PPI recommends that residents dress with long sleeves, pants and closed-toe shoes when outdoors, drain standing water and use insect repellant, especially at dusk and dawn.

West Nile virus is usually transmitted to humans and other mammals through mosquitos that have fed on infected birds, but never through human contact, according to the DCHD website. The virus — which originated in East Africa and has since been observed in all 48 continental states — was first detected in DuPage County in 2004, as stated on the Illinois Department of Health website. DuPage County reported nine cases of human infection last year, and five during 2014.

Professor O. Michael Bubu, instructor of applied health science at Wheaton, said that 70 to 80 percent of individuals infected will not exhibit any symptoms or be affected by the virus. For those who are affected, Bubu said that symptoms are typically “mild, normal viral symptoms that will run the course,” such as fever and body aches or pains. For these individuals, symptoms will occur in three to 14 days after being infected by a mosquito and last only a few days, according to DCHC.

In some cases, however — particularly in elderly, very young or chronologically ill individuals — symptoms can be much more severe. Usually these are “neurological symptoms,” such as neck stiffness, fever and inflammation of the brain or its surrounding tissues and indicate neurological illness, Bubu said. Neurological illness only develops in under one percent of infected individuals, but is life-threatening. There is no known treatment for the virus.

Bubu told The Wheaton Record that “any news about an infection should be taken seriously, and people should take precautionary and preventative measures so that they don’t get infected.”

While Black said that she is not aware of any cases of West Nile virus that have occurred on Wheaton’s campus in the past, Student Health Services is prepared should a case appear. She listed “weekly communication with epidemiologists at DCHD, medical memos and huddles among the team … excellent laboratory resources if testing is needed [and] seasoned clinicians” among the ways Student Health Services is equipped to respond.

Cases of West Nile Virus most commonly occur between June and September. The DCHD website notes that “WNV activity generally decreases in the fall once cooler temperatures arrive and especially after the first frost of the season.”