The number of STIs (sexually transmitted infections) will vary depending on what is counted as an STI and whether sexually transmissible infections are counted. The Medical Institute uses a list of STIs that is adapted from chapter headings in a standard STI textbook¹. This list, which appears below in alphabetical order, has 27 different infections.

Bacterial:

1. bacterial vaginosis

2. chancroid

3. chlamydia

4. donovanosis

5. gonorrhea

6. lymphogranuloma venereum

7. mycoplasma, genital

8. syphilis

9. treponematosis, endemic

Ectoparasitic:

10. lice, pubic

11. scabies

12. candidiasis, vulvovaginal

Protozoal:

13. amebiasis

14. cryptosporidium

15. giardiasis

16. trichomoniasis

Viral:

17. cytomegalovirus

18. Epstein Barr virus

19. hepatitis A

20. hepatitis B

21. hepatitis C

22. hepaptitis D

23. herpes simplex virus (HSV-1 and HSV-2)

24. human immunodeficiency virus (HIV)

25. human papillomavirus (HPV)

26. human T-cell lymphotropic virus (HTLV-1)

27. molluscum contagiosum

Reviewed by: Jennifer A. Shuford, MD, MPH

Date: October 2008

Reference:

1. Holmes KK, Sparling PF, Stamm WE, et al. Sexually Transmitted Diseases, 4th Ed. New York, NY: McGraw Hill Medical; 2008.