Sexually transmitted infections

Consider screening for sexually transmitted infections in the following situations:

  • before starting a sexual relationship with a new partner

  • your partner has cheated on you or has multiple sexual partners

  • you have multiple partners

  • you have symptoms that suggest that you might have a sexually transmitted infection

A reliable test result may be obtained at different intervals after the last exposure for different sexually transmitted infections: 2 weeks for gonorrhea and Chlamydia, 3 months for syphilis, and 3 months for HIV, hepatitis B and C.


For pregnant women, the sexually transmitted infections that may affect the fetuses include genital herpes, gonorrhea, Chlamydia, hepatitis B, HIV, and syphilis. Routine blood tests done during pregnancy screen for only 3 of the sexually transmitted infections: syphilis, hepatitis B and HIV only. Please inform me if you are at-risk for sexually transmitted infections, and I could screen you for the other infections.





1. Genital herpes


Herpes is a common and usually mild recurrent skin condition caused by the herpes simplex virus (HSV). A person may show symptoms within days after contracting genital herpes, or it may takes weeks to years even. The first episode may be severe within days after the exposure or so mild that it is not even noticed. Hence it can be difficult to know for sure when and from whom one may have contracted the virus.


There are 2 types of HSV: HSV-1 and HSV-2. Oral herpes is commonly called cold sores, and is almost always due to HSV-1 infection. Genital herpes, on the other hand, is usually caused by HSV-2 infection though HSV-1 is increasingly a cause of genital herpes due to increasing practices of oral sex.


First episode of genital herpes


At the first episode, the classic symptoms are sores, vesicles or ulcers present on the penis or vulva. These may resemble small pimples or blisters that eventually crust over and finally scab like a small cut. They may heal fully between 2 to 4 weeks, during which a second crop of skin conditions may appear and some will experience flu-like symptoms, including fever and swollen glands near the groin, sometimes with headache and painful urination. Treatment with antiviral drugs is standard and can speed healing quickly. See video on Understanding Genital Herpes - video by American Sexual Health Association (ASHA)




Recurrent herpes


If the genital herpes is caused by HSV-2, it is more likely to have recurrent genital herpes (typically 4-5 times a year) which tends to be milder and heal quicker in 2-12 days. Genital herpes caused by HSV-1 may never recur or only recur 1 time in one to a few years. The frequency of recurrent genital herpes may reduce with effective stress management, getting adequate rest, nutrition and exercise. If the outbreaks are too frequent, daily suppressive antiviral therapy can reduce outbreak by up to 80%. See video on Benefits of Herpes testing - video by American Sexual Health Association (ASHA) and Who should be tested for Herpes? - video by American Sexual Health Association (ASHA)





Testing


Herpes can be confirmed with a swab from the ulcers for Herpes PCR tests. Where there is no visible signs at the time of testing, HSV-1 IgG and HSV-2 IgG tests can be performed. However these tests for antibodies may still be a false negative as the antibody levels could become detectable only after a few weeks to a few months. For the most accurate tests, it is recommended to wait 16 weeks from the last possible date of exposure before getting a blood test. See video on Understanding Herpes testing - video by American Sexual Health Association (ASHA)




Treatment


For first clinical episode of genital herpes - to reduce symptoms and to reduce recurrent attacks


1. Acyclovir 400 mg three times a day for 7-10 days (or longer till healing is complete)


2. Valacyclovir 1 g twice a day for 7-10 days (or longer till healing is complete)



For recurrent genital herpes


1. Acyclovir 800 mg twice a day for 5 days


2. Valacyclovir 500 mg twice a day for 3 days or 1 g once a day for 5 days



Prevention


In a monogamous relationship where both partners already have the same type of HSV infection, unprotected sexual intercourse does not lead to more frequent recurrences. However, if only one partner has HSV infection, the strategies to prevent spread of genital herpes include:


a) avoiding sexual contact between outbreaks


b) use of condoms for sexual contact between outbreaks


c) use of daily suppressive antiviral treatment with valacyclovir



Suppressive treatment for recurrent genital herpes


1. Acyclovir 400 mg twice a day


2. Valacyclovir 500 mg once a day or 1 g once a day (for patients with >= 10 episodes per year)



Herpes and pregnancy


Babies are at most at risk for neonatal herpes if the mother contracts a first episode of genital herpes late in pregnancy. See video on Herpes and pregnancy - video by American Sexual Health Association (ASHA)



For pregnant women with a known history of genital herpes, the following could be done:


1. Consider use of acyclovir from 36 weeks to prevent recurrence during delivery.


2. Examination for any sores or signs of an outbreak (e.g. itching, tingling, pain) in early labour.


3. Consider Caesarean section to prevent risk of neonatal herpes.


4. Look out for symptoms of neonatal herpes (skin rash, fever, crankiness or lack of appetite) for the first 3 weeks after baby is born.



2. Gonorrhea


See video on What is Gonorrhea? Why is untreated gonorrhea so serious?



Gonorrhea is a bacterial infection transmitted during vaginal, anal and oral sex (performing or receiving). It can be transmitted when the mucous membrane comes into contact with the mucous membrane secretions or semen of an infected person, even if the penis or tongue does not go all the way into the vagina or anus. It can be passed from mother to newborn as the baby passes through the infected birth canal, which may result in eye infections, pneumonia or other complications that develop 5-12 days after birth.


Men with gonorrhea tend to have symptoms (usually yellowish-white discharge from the penis, burning pain when urinating, urinating more often than usual, or pain or swelling of the testicles) while women with gonorrhea tend not to have symptoms (though occasionally might have yellow or greenish discharge, or sometimes bloody vaginal discharge, burning or pain when urinating, or pain during sexual intercourse). For women, untreated gonorrhea may cause complications such as pelvic inflammatory disease, ectopic pregnancy, infertility and/or chronic pelvic pain.


Testing


Gonorrhea can be tested from the urethral swab, endocervical swab or first catch urine tests for PCR tests or culture.


Treatment


Dual therapy with intramuscular ceftriaxone (Rocephine) 250 mg injection and azithromycin 1 g orally.


Retesting is only recommended if compliance to the treatment is not complete, if there are persistent symptoms or reinfection is suspected.


3. Chlamydia


Chlamydia is probably the most common bacterial sexually transmitted infection among young adults, and most women (and half the men) with Chlamydia do not have symptoms. Women may have abnormal vaginal discharge or burning pain during urination. It is transmitted primarily during anal or vaginal sex. It can be passed even if the penis does not go all the way into the vagina or anus. It can be passed from mother to newborn as the baby passes through the infected birth canal, which may result in eye infections, pneumonia or other complications. If left untreated, it could lead to pelvic inflammatory disease, ectopic pregnancy, infertility and/or chronic pelvic pain.


Testing


Chlamydia can be tested from the urethral swab, endocervical swab or first catch urine tests for PCR test.



Treatment


Azithromycin 1 g orally or Doxycycline 100 mg twice a day for 7 days


Retesting is only recommended if compliance to the treatment is not complete, if there are persistent symptoms or reinfection is suspected.


4. Syphilis


Syphilis is a bacterial infection that can be transmitted during vaginal, oral and anal sex, even if there is no sexual penetration. It can be transmitted during pregnancy or during childbirth from a mother to the baby.


There are 4 stages of syphilis:


  • Primary syphilis - A chancre appears as a single painless sore that is raised or elevated within 10-90 days after contact. This is seen on the penis, scrotum, vulva or anus. It can last 3-6 weeks.

  • Secondary syphilis - A rash on the palms or soles, syphilitic "warts", flat round grayish-white sores on the mouth, throat and cervix, or a general sense of ill heath may develop 2 weeks to 6 months after infection.

  • Latent syphilis - Period of time (2-30+ years after infection) when there are no signs or symptoms. Only diagnosed by blood test.

  • Late stage syphilis - May affect the heart and brain.


Testing


Syphilis is diagnosed when blood tests for VDRL and TPHA are both positive.


Treatment


1. Primary and secondary syphilis - Intramuscular benzathine Penicillin G 2.4 million units for a single dose.


2. Latent syphilis - Intramuscular benzathine Penicillin G 2.4 million units weekly for 3 doses.

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