With the 2020 presidential election less than three months away, new research suggests an election can be held safely if stringent steps are taken to lower COVID-19 infection risk.

The conclusion follows a U.S. Centers for Disease Control and Prevention investigation that looked at what happened in the city of Milwaukee this past April after Wisconsin became the first state to hold an election in the midst of the pandemic.

The bottom line: the election did not appear to trigger an uptick in cases, hospitalizations or deaths due to COVID-19.

The caveat: the vast majority of voters (68%) cast mail-in absentee ballots. And those who voted in person did so under the watchful eyes of the state National Guard and city health department staff.

According to study author Eva Leidman — an epidemiologist with the CDC’s emergency response and recovery branch in Atlanta — adhering to safety recommendations is critical.

The CDC, said Leidman, supports safety measures such as “hand-washing, staying home when sick, coughing and sneezing [into the] elbow, and face coverings.” Environmental cleaning and disinfection are also important, she added, in an effort “to make sure Americans can participate safely in elections.”

Beyond that, a CDC directive issued in late June also advocates a “wide variety of voting options” and longer voting periods, whether that involves weeks of early voting or longer hours on election day. And it warns that “elections with only in-person voting on a single day are higher risk for COVID-19 spread because there will be larger crowds and longer wait times.”

The June directive was issued well after Wisconsin’s April 7 primary elections. But Leidman and her colleagues found that the voters of Milwaukee seem to have preemptively embraced much of the same thinking.

For example, in recent weeks, President Donald Trump has publicly disparaged the wide-scale use of absentee ballots, going so far as to float the idea of postponing the upcoming November election based on claims that mail-in votes are vulnerable to massive fraud.

But Milwaukee voters clearly had no such qualms. Statewide public health messaging strenuously encouraged absentee voting, and the Milwaukee Election Commission found that 68% of Milwaukee voters heeded that call in 2020, up from 4% in 2016.

Similarly, early voting jumped 160%, rising from just under 5% of voters in 2016 to 12% in 2020.

By contrast, while in-person election day voting accounted for 91% of all votes cast in 2016, that figure plummeted to less than 20% in 2020.