The US Centers for Disease Control and Prevention (CDC) reports that about one in six Americans struggles with substance use disorder (SUD). People with SUD are more likely to get serious infections like hepatitis A, B, and C, HIV, tuberculosis, and sexually transmitted infections (STIs) such as gonorrhea, chlamydia, and syphilis. These infections can spread in communities with limited access to healthcare. A 2025 study by the University of Pennsylvania Health System found that better screening for infections during SUD treatment can help detect, prevent, and treat these diseases more effectively. The study had two parts. The first part, called ‘usual care,’ ran from September 2021 to June 2022. During this time, patients were tested for infections based on standard guidelines, which included a routine hepatitis C test. The second part, called the ‘intervention’ phase, took place from September 2022 to June 2023. In this phase, patients worked with a nurse trained in infectious diseases. The nurse helped them get tested for HIV and hepatitis, checked for STIs and tuberculosis exposure, and provided treatment when needed. The results showed much higher screening rates in the intervention group compared to the usual care group. For example, hepatitis A testing increased from 6.1% to 90.3%, hepatitis B from 8.8% to 91.3%, and HIV from 23.8% to 76.8%. The study also found that patients in the intervention group were more likely to get vaccines, such as hepatitis A (58.0% vs. 0.0%) and hepatitis B (71.0% vs. 0.0%), and to start HIV prevention medication (PrEP). Treatment rates for infections like hepatitis C, gonorrhea, and syphilis were also higher in the intervention group. Experts predict that in 2025, millions of Americans will be living with these infections. Since people with SUD are at higher risk, better screening during treatment can help stop the spread of these diseases. This approach not only improves health outcomes but also reduces the overall number of infections in the population.