US STI Rates by the Numbers: A Quiz Based on the Latest CDC Data
SAMPLE: Approximately what percentage of the total US population had an STI at a given point in 2018? Plus 6 more questions on STI trends based on the latest CDC data.
The US Centers for Disease Control and Prevention (CDC) last published estimates of sexually transmitted infections (STIs) in the US in 2008. A new CDC report provides updated estimates for 2018 that shed light on the scope of STIs in the US and what populations are most affected.
Published January 25, 2021 in the journal Sexually Transmitted Diseases, CDC researchers analyzed the prevalence and incidence of 8 common STIs (chlamydia, gonorrhea, trichomoniasis, syphilis, genital herpes, human papillomavirus, hepatitis B, and HIV) in the US in 2018. The 7-question quiz below focuses only on chlamydia, gonorrhea, and syphilis as they are nationally notifiable STIs. Find out the results and key takeaways for primary care in this quick quiz.
1. Approximately what percentage of the total US population had an STI at a given point in 2018?
Answer: B. 20%. Approximately 20% of the total US population (1 in 5 people) had an STI at a given point in 2018. Persons aged 15-24 years comprised 18.6% of all prevalent infections; however, they comprised almost half (45.5%) of all incident infections.
2. In 2018, what was the estimated number of prevalent urogenital chlamydial infections among persons aged 15-39 years?
Answer: B. 2.4 million. In 2018, there were an estimated 2.4 million prevalent urogenital chlamydial infections among persons aged 15-39 years; 1.1 and 1.3 million infections among men and women, respectively. When looking at incident infections only, there were approximately 4 million chlamydial infections among the same age group.
3. True or false? Persons aged 15-24 years comprised the majority (66.5%) of all incident urogenital chlamydial infections in 2018.
Answer: A. True. In 2018, there were approximately 2.6 million total incident urogenital chlamydial infections among persons aged 15-24 years, representing 66.5% of all incident chlamydial infections
4. What was the estimated prevalence of urogenital gonococcal infections among 15-39-year-olds?
Answer: B. 209 000. In 2018, there were an estimated 209 000 prevalent urogenital gonococcal infections among persons aged 15-39 years (50 000 in men, 155 000 in women). Among all prevalent gonococcal infections, 107 000 demonstrated resistance or elevated minimum inhibitory concentrations (MICs) to antibiotics tested.
5. Approximately how many of the 1.6 million incident infections of gonorrhea demonstrated resistance or elevated MICs to antibiotics tested?
Answer: D. 804 000. The estimated number of incident gonococcal infections among 15-39-year-olds was 1.6 million, 804 000 of which demonstrated resistance or elevated MICs to antibiotics tested.
6. True or false? Among 156 000 prevalent syphilitic infections in 2018, infections in women comprised 71.8% of all infections.
Answer: B. False. In 2018, there was an estimated 156 000 prevalent syphilitic infections among persons aged 14-49 years, and infections in men comprised 71.8% of all infections (112 000 infections) whereas 38 000 infections occurred among women.
7. Approximately how many new syphilitic infections occurred among 14-49-year-olds in 2018?
Answer: C. 146 000. The number of incident syphilitic infections among 14-49-year-olds was 146 000, with men comprising 82.9% of all incident infections.
