Kentucky’s hepatitis A virus (HAV) outbreak has sickened more than 4,100 people and claimed the lives of 43 others since 2018, making it the nation’s largest and deadliest. Looking back, advocates say the state’s response was “too low and too slow” to contain the spread of the virus, the Courier Journal reports.

Robert Brawley, MD, Kentucky’s infectious disease chief sounded the alarm about a sudden uptick in new hepatitis A infections last spring. By that time, 400 people in Louisville had already contracted the virus, which, fueled by increasing injection drug use and homelessness, quickly spread across Appalachia.

“Need to move faster,” Brawley wrote in an April 2018 email to Kentucky health department colleagues. “The virus is moving faster than we are immunizing persons [at] risk.” The letter ultimately called for $10 million dollars to combat the crisis, including $6 million for hepatitis A vaccines and $4 million for temporary health workers to administer them. He also lobbied for the state to declare a public health emergency—but it appears the department did not listen.

Instead, the Courier Journal reports, Kentucky allocated only $2.2 million to local health departments to combat the virus’s spread. In addition, county health departments added little to no staff to step up hepatitis A vaccination efforts and failed to try strategies used by other states with limited budgets to reach out to drug users and homeless people.

That said, given the challenges and unpredictability of viral outbreaks, it would have been impossible for the state’s public health team to anticipate just how fast hepatitis A would makes its way across the state—and the country.

More than 13,000 Americans have been sickened with HAV over the past year, which advocates say should serve as a warning to other states that they must devote more resources toward prevention and containment of such outbreaks as soon as they strike.

In fact, experts agree that the best way to bring hepatitis A under control is to hit it hard and fast—distributing vaccines and ramping up outreach in at-risk communities as quickly as possible. While expensive at first, this approach saves money in the end and benefits everyone.