State public health officials announced Friday that the southern Illinois measles outbreak had ended.

At a news conference in Springfield, Illinois Department of Public Health director Dr. Sameer Vohra said the state had once again thwarted “one of the most contagious viruses on Earth.”

“We make this announcement knowing the spread of measles continues to be a threat, but it’s a moment to acknowledge Illinois’ public health effort,” Vohra said. “But in Illinois, we’re relieved to tell a much different story.”

The health department reported the state’s first confirmed measles case at a clinic in far southern Illinois in April. Cook County’s first two cases followed a week later.

At least 1,288 cases have been confirmed nationwide as of July 8, the most in more than 30 years and the largest spike in cases since 2019, according to the Centers for Disease Control and Prevention. Three people have died from it, including an unvaccinated child in West Texas, the first confirmed measles death in the U.S. in 10 years.

Vohra said last year’s three-month measles outbreak in Chicago, where 64 cases were confirmed, prompted officials to “watch intently as measles cases began to spread in alarming numbers in other states. So when out first Illinois case was diagnosed in April, we took immediate action.”

“This doesn’t mean we won’t see any more measles cases this year,” Vohra continued. “If people don’t receive timely immunizations, then vaccine-preventable illnesses like measles can surface again.”

A Sun-Times analysis in May found just about 45% of CPS schools are at a 95% measles vaccination rate, the CDC’s benchmark for herd immunity that protects vulnerable students and kids with weakened immune systems.

That’s down from the rate in 2019, the year before the pandemic, when 90% of schools were at community-wide immunity.

While no children in Illinois contracted the virus this year, Jennifer Suh, a pediatric medicine medical advisor at IDPH, cautioned that parents still needed to vaccinate their children and be vigilant for the signs of infection.

About 92% of all cases in the U.S. this year are in unvaccinated individuals, and the largest share were children aged 5 to 19.

Symptoms of the virus include a fever of 101 degrees or higher, cough, runny nose and a rash that starts on the head around the hairline and moves down the body, lasting for about three days, though some can be longer, according to the state health department.

The best protection is the MMR vaccine, according to Vohra, as nine out of 10 unvaccinated people exposed to the airborne virus will contract it.

While vaccination rates have dropped in recent years, more than 9,000 MMR vaccines were given in Illinois between February and May, and MMR vaccination rates statewide increased 50% between February and May, according to state health officials.

“We need to maintain this momentum,” Suh said. “Especially as we prepare for the school year.”

Contributing: Kaitlin Washburn