Sexually transmitted infections (STIs) constitute a major burden on global health, as this group of infections rank among the top five disease categories for which adults seek healthcare.1 More than 1 million people acquire an STI every day.1
The astounding incidence of these infections places the healthcare system under severe economic strain. In the US, the lifetime cost of treating eight of the most common STIs contracted in just one year is $15.6 billion.2 Furthermore, the total direct medical cost in the US associated with chlamydia, gonorrhea, and Herpes Simplex Virus-2 (HSV-2) infections alone is estimated to be a staggering $1.2 billion annually.3
However, the substantial monetary costs on healthcare overall cannot be overshadowed by the severe health consequences shouldered by those inflicted by these infections. Chlamydia and gonorrhea are known to cause infertility, and HSV-2 can cause painful chronic infection.1,2
Contributing to the challenge of infection control is the asymptomatic nature of these STIs, which can facilitate greater spread of disease in a population by unaware carriers.
Through effective screening from clinical microbiology and infection control, healthcare facilities can monitor epidemic outbreaks, in addition to providing proper identification and treatment of infections.
Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are among the most common sexually transmitted infections (STIs), with new cases in adults totaling 105.7 million and 106.1 million, respectively.4
The incidence of these infections underscores their considerable cost burden to the healthcare system. The total direct medical cost for chlamydia in the US is estimated to be $516 million per year while the total direct medical cost for gonorrhea in the US is estimated to be $162.1 million per year.3
On top of these monetary costs, the asymptomatic nature of CT/NG adds to the complexity of treatment and infection control as carriers may transmit the bacteria unknowingly. Of the infected population:
Additionally, antimicrobial resistance to STIs, particularly those infected with NG, has complicated the efforts to reduce the impact of STIs globally.1 The emergence of decreased susceptibility of NG to the “last line” treatment option (oral and injectable cephalosporins) together with antimicrobial resistance already shown to penicillins, sulphonamides, tetracyclines, quinolones, and macrolides make NG a multidrug-resistant organism.7
Clinical microbiology and infection control must partner together to solidify effective screening and diagnostic tools in asymptomatic and symptomatic populations to contain silent disease transmission, reduce CT/NG prevalence, and further improve the understanding of these infections.
Herpes Simplex Virus (HSV) is known as one of the most common STIs, with more than 530 million people worldwide infected with genital herpes.1
The economic burden of HSV-2 further highlights the significant impact of this virus. The total direct medical cost in the US for HSV-2 is estimated to be $540.7 million per year.3
However, HSV-2 is one of the most overlooked STIs, as clinical presentation for HSV infection is variable, and frequently signs and symptoms can be easily confused with other conditions, complicating efforts for detection and treatment of infection. Approximately 70 to 90% of patients with reactive serology for HSV-2 have not been diagnosed with genital herpes.8
Untreated and undiagnosed HSV can lead to varying and severe health consequences. HSV-2 can result in painful chronic infection, miscarriage or premature birth, and fatal infection in newborns.2
Due to differing outcomes regarding disease severity, sequelae, and recurrence rates, it is essential to differentiate if a patient has HSV-2 or HSV-1, the latter of which occurs during early childhood and has less frequent recurrence. Laboratory confirmation is recommended for all patients with suspected genital herpes, using methods that directly demonstrate the virus in genital specimens.
As herpes viruses continue to evolve, and evidence of drug resistance is being reported, laboratories play an important role in accurate identification and typing of HSV to direct therapy, prevent recurrence, and limit transmission of the virus.
1. World Health Organization. Sexually transmitted infections (STIs).http://www.who.int/mediacentre/factsheets/fs110/en/. Publication date unavailable. Updated November 2013. Accessed April 15, 2014.
2. Centers for Disease Control and Prevention. Incidence, prevalence, and cost of sexually transmitted infection in the United States. http://www.cdc.gov/std/stats/sti-estimates-fact-sheet-feb-2013.pdf. Published February 2013. Accessed April 15, 2014.
3. Owusu-Edusei K, Chesson HW, Gift TL, et al. The estimated direct medical cost of selected sexually transmitted infection in the United States, 2008. Sex Transm Dis. 2013;40(3):197 201. doi:10.1097/OLQ.0b013e318285c6d2.
4. World Health Organization, Department of Reproductive Health and Research. Global incidence and prevalence of selected curable sexually transmitted infections – 2008. http://apps.who.int/iris/bitstream/10665/75181/1/9789241503839_eng.pdf. Published 2012. Accessed April 15, 2014.
5. Stamm WE, Holmes KK. Chlamydia trachomatis infections in the adult. In: Holmes KK, Mardh PA, Sparling PF, et al., eds. Sexually transmitted diseases. 2nd ed. New York, NY: McGraw-Hill; 1980:181-193
6. Judson FN. Gonorrhea. Med Clin North Am. 1990;1353-1367
7. World Health Organization, Department of Reproductive Health and Research. Global action plan to control the spread and impact of antimicrobial resistance in Neisseria gonorrhoeae. http://whqlibdoc.who.int/publications/2012/9789241503501_eng.pdf?ua=1. Published 2012. Accessed April 15, 2014.
8. Fleming et al. 1997 Herpes Simplex Virus Type 2 in the United States 1976 to 1994. NEJM 337: 1105-1111.