Symptoms of Sexually Transmitted Infection

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Many people carrying a sexually transmitted infection (STI) either do not have any symptoms or only present very mild ones. Generally, STIs pass unnoticed more often in women (they present less symptoms). That is why STIs are commonly diagnosed later in women and therefore cause more damage.

The tell-tale symptoms of an STI sometimes appear days or months after infection.

Genital herpes in women

Ulcers on the genitals, perianal area or mouth.

Swollen ganglion in the area of ​​the vagina

Swollen lymph glands (adenopathy) appear as a lump, which may or may not be tender, in the groin region.

Vaginal discharge with odour

In women, thick or foul-smelling vaginal discharge, stinging or pain when urinating or during sexual intercourse.

Discharge from the penis with pain

In men, purulent (pus-like) discharge from the urethra, pain or stinging.

Rectal bleeding with pain

Rectal pain or rectal discharge of pus, mucus or blood, in people who engage in anal sex.

There are many different STIs that can manifest in a variety of ways and may even pass totally undetected:


Symptoms of human papillomavirus (genital warts or condylomas)

Individuals infected with human papillomavirus (HPV), which as we said earlier is the world’s most common STI, may present genital warts, also known as condylomas. These are generally small and often dark verruca-like lesions that usually neither hurt nor itch and develop on the genitals, perianal area or mouth.

Some types of papillomavirus can lead to cervical cancer in women (in the vast majority of cases these are not the same strains as those which cause warts or condylomas). However, given that they are different types of virus, when a woman or her partner is diagnosed with genital warts it does not imply that she must undergo any special cervical cancer screening (cytology) – each woman should attend their specific screening schedule according to their age or condition. Patients should use a barrier method at least while they have warts.

Some types of cancer, mainly cervical cancer plus some others such as cancer of the anus, vulva, vagina or penis, can be caused by certain types of human papillomavirus. However, we know that genital warts, which are very common, are benign in the vast majority of patients and their diagnosis does not imply the need for more tests to detect the presence of these types of cancer.

Genital herpes in women

Symptoms of herpes

People with genital herpes may present groups of small painful ulcers on the genitals or buttocks. The ulcers spontaneously cure themselves in a few days, even without treatment. Patients with a herpes infection may present more than one of these episodes in the form of outbreaks of small ulcers, generally in the same area (the genitals or buttocks).

A barrier method should be used during sex at the first signs of any discomfort in the area and until the ulcers in each outbreak have been cured as they are more infectious in this period.

The first episode of genital herpes is sometimes more severe and intense than subsequent episodes as it presents more ulcers, is more painful and is often accompanied by general malaise and swollen lymph glands (adenopathy).

Symptoms of gonorrhoea in a man

Symptoms of gonorrhoea and genital Chlamydia infection

Individuals with gonococcal (gonorrhoea) or Chlamydia infections present discomfort, pain or stinging when urinating and sometimes urethral discharge. These bacteria may also cause rectal inflammation (pain when defecating, rectal discharge of pus, mucus or blood) which mainly affects people who engage in anal sex. Both infections can go undetected in some people which complicates diagnosis. Asymptomatic infection (without presenting any signs or symptoms) is more common for Chlamydia and occurs more frequently, for both infections, in women than in men.

Genital warts symptom of syphilis

Symptoms of syphilis

A painless ulcer may appear at first (within days of infection), generally on the genitals or in the perianal region, accompanied by swollen lymph glands (adenopathy) in the groin (a painless lump in the groin area).

Ulcers disappear after a few days even if the patient does not receive any syphilis treatment. Skin lesions may appear at a later date (days/weeks). These most often manifest as pinkish blotches on the trunk and extremities that are neither painful nor itchy. The appearance of either reddish-brown round stains on the palms of the hands or soles of the feet, or blotches or erosions on the mouth or genitals is also a frequent sign of this infection. Furthermore, there are many other less frequent forms of presentation and it is important to remember that syphilis is sometimes totally asymptomatic and may therefore go undetected.

Vaginal discharge with odour

Symptoms of Trichomonas vaginalis

Trichomonas infection can go unnoticed or produce an abnormal, foul-smelling vaginal discharge. It is sometimes accompanied by stinging or itchiness in the vulva or vagina.

Rectal bleeding with pain

Symptoms of lymphogranuloma venereum

Lymphogranuloma venereum (LGV) can initially appear as a genital ulcer. However, most people infected with LGV initially complain of discomfort due to swelling in the rectum (pain when defecating, rectal discharge of pus, mucus or blood) possibly accompanied by fatigue, fever or abdominal pain and ulcers may sometimes appear on the genitals or the area around the anus.

People with  jaundice, yellow skin

Symptom of hepatitis A, B and C

Hepatitis A, B and C are viral infections of the liver. Viral hepatitis follow disease patterns with varying degrees of severity; however, hepatitis B and C viruses can develop into chronic infections, which in some cases could eventually trigger cirrhosis or even liver cancer, whereas hepatitis A only has an acute phase.

During the acute phase, some patients may present yellowish skin and eyes (jaundice), darker urine, nausea, vomiting, abdominal pain, general malaise or fatigue. Nevertheless, many patients do not present any symptoms in the acute phase. In addition, a small group of patients may suffer acute liver failure which can even lead to death. In some cases when hepatitis B and C become chronic, the hepatic compromise could result in liver cirrhosis (liver failure) or even liver cancer

Pubic irritation in a woman

Symptoms of pediculosis pubis

This infection is caused by some parasites similar to head lice that mainly cause itching and sometimes irritation of the pubis and hairy areas of the trunk or armpits.

Person scratching his face

Symptoms of scabies

Scabies causes intense and generalised itching that increases at night. The itchiness is often stronger between the fingers and around the genitals. It is highly infectious and so it often affects people living with the infected person.

Substantiated information by:

Irene Fuertes De Vega
José Luis Blanco Arévalo
Mercè Alsina Gibert
Núria Borrell Iragari

Published: 20 February 2018
Updated: 20 February 2018

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