Some people prefer the term STI because they think it's more accurate. Not everyone with an infection has symptoms, and since there is technically no such thing as a disease without symptoms, they say STI is the most scientifically accurate term. The first difference between STDs and STIs is in the name. STD stands for sexually transmitted disease, while STI stands for sexually transmitted infection.
Basically, the difference is between a disease and an infection. Most patients say “STDs” in health centers, and more people search for “STDs” than “STIs” online. When I first noticed the ambiguity of the terms STDs and STIs, I thought that STIs were simply a more politically correct way of referring to infected people. Hunter Handsfield, emeritus professor of medicine at the Center for AIDS and STDs at the University of Washington, who has studied sexually transmitted diseases for 40 years.
We recommend that journals on sexually transmitted diseases and other peer-reviewed journals, especially those that frequently publish content on sexual behavior, adopt an explicit policy to encourage authors to use accurate and neutral language when referring to sexual behavior and possible associated risks. To understand if there are fundamental differences between STDs and STIs, it is useful to deconstruct the meaning of each term. The CDC estimates that people ages 15 to 24 get half of all new cases of STDs, while one in four sexually active teens has an STD.