In males, the lesions occur on the glans penis, shaft of the penis or other parts of the genital region, on the inner thigh, buttocks, or anus. In females, lesions appear on or near the pubis, clitoris or other parts of the vulva, buttocks or anus.

Other common symptoms include pain, itching, and burning. Less frequent, yet still common, symptoms include discharge from the penis or vagina, fever, headache, muscle pain (myalgia), swollen and enlarged lymph nodes and malaise. Women often experience additional symptoms that include painful urination (dysuria) and cervicitis. Herpetic proctitis (inflammation of the anus and rectum) is common for individuals participating in anal intercourse.

After 2–3 weeks, existing lesions progress into ulcers and then crust and heal, although lesions on mucosal surfaces may never form crusts. In rare cases, involvement of the sacral region of the spinal cord can cause acute urinary retention and one-sided symptoms and signs of myeloradiculitis (a combination of myelitis and radiculitis): pain, sensory loss, abnormal sensations (paresthesia) and rash. Historically, this has been termed Elsberg syndrome, although this entity is not clearly defined.

Neonatal herpes simplex is a HSV infection in an infant. It is a rare but serious condition, usually caused by vertical transmission of HSV-1 or -2) from mother to newborn. During immunodeficiency, herpes simplex can cause unusual lesions in the skin. One of the most striking is the appearance of clean linear erosions in skin creases, with the appearance of a knife cut. Herpetic sycosis is a recurrent or initial herpes simplex infection affecting primarily the hair follicles. Eczema herpeticum is an infection with herpesvirus in patients with chronic atopic dermatitis may result in spread of herpes simples throughout the eczematous areas.

Herpetic keratoconjunctivitis, a primary infection, typically presents as swelling of the conjunctiva and eyelids (blepharoconjunctivitis), accompanied by small white itchy lesions on the surface of the cornea.

Herpetic sycosis is a recurrent or initial herpes simplex infection affecting primarily the hair follicle.

Genital herpes is an infection by herpes simplex virus (HSV) of the genitals. Most people either have no or mild symptoms and thus do not know they are infected. When symptoms do occur, they typically include small blisters that break open to form painful ulcers. Flu-like symptoms may also occur. Onset is typically around 4 days after exposure with symptoms lasting up to 4 weeks. Once infected further outbreaks may occur but are generally milder.

The disease is typically spread by direct genital contact with the skin surface or secretions of someone who is infected. This may occur during sex including oral sex. Active sores are not required for transmission to occur. HSV is classified into two types, HSV-1 and HSV-2. While historically mostly cause by HSV-2, genital HSV-1 has become more common in the developed world. Diagnosis may occur by testing lesions using either PCR or viral culture or blood tests for specific antibodies.

Efforts to prevent infection include not having sex, using condoms, and only having sex with someone who is not infected. Once infected their is no cure. Antiviral medications may, however, prevent outbreaks or shorten outbreaks if they occur. The long term use of antivirals may also decrease the risk of further spread.

In 2015 about 846 million people (12%) had genital herpes. Women are more commonly infected than men. Rates of disease caused by HSV-2 have decreased in the United States between 1990 and 2010. Complications may rarely include aseptic meningitis, an increased risk of HIV/AIDS if exposed, and spread to the baby during childbirth resulting in neonatal herpes.

HSV infection causes several distinct medical disorders. Common infection of the skin or mucosa may affect the face and mouth (orofacial herpes), genitalia (genital herpes), or hands (herpetic whitlow). More serious disorders occur when the virus infects and damages the eye (herpes keratitis), or invades the central nervous system, damaging the brain (herpes encephalitis). People with immature or suppressed immune systems, such as newborns, transplant recipients, or people with AIDS, are prone to severe complications from HSV infections. HSV infection has also been associated with cognitive deficits of bipolar disorder, and Alzheimer's disease, although this is often dependent on the genetics of the infected person.

In all cases, HSV is never removed from the body by the immune system. Following a primary infection, the virus enters the nerves at the site of primary infection, migrates to the cell body of the neuron, and becomes latent in the ganglion. As a result of primary infection, the body produces antibodies to the particular type of HSV involved, preventing a subsequent infection of that type at a different site. In HSV-1-infected individuals, seroconversion after an oral infection prevents additional HSV-1 infections such as whitlow, genital herpes, and herpes of the eye. Prior HSV-1 seroconversion seems to reduce the symptoms of a later HSV-2 infection, although HSV-2 can still be contracted.

Many people infected with HSV-2 display no physical symptoms—individuals with no symptoms are described as asymptomatic or as having subclinical herpes.

The symptoms can be mild or severe and may include:

- Not able to chew or swallow

- Sores on the inside of the cheeks or gums

- Fever

- General discomfort, uneasiness, or ill feeling

- Very sore mouth with no desire to eat

- Halitosis (bad breath)

The term "labia" means "lip". Herpes labialis does not refer to the labia of the genitals, though the origin of the word is the same. When the viral infection affects both face and mouth, the broader term "orofacial herpes" is used, whereas the term "herpetic stomatitis" is used to specifically describe infection of the mouth; "stomatitis" is derived from the Greek word stoma that means "mouth".

Herpes infections usually show no symptoms; when symptoms do appear they typically resolve within two weeks. The main symptom of oral infection is inflammation of the mucosa of the cheek and gums—known as acute herpetic gingivostomatitis—which occurs within 5–10 days of infection. Other symptoms may also develop, including headache, nausea, dizziness and painful ulcers—sometimes confused with canker sores—fever, and sore throat.

Primary HSV infection in adolescents frequently manifests as severe pharyngitis with lesions developing on the cheek and gums. Some individuals develop difficulty in swallowing (dysphagia) and swollen lymph nodes (lymphadenopathy). Primary HSV infections in adults often results in pharyngitis similar to that observed in glandular fever (infectious mononucleosis), but gingivostomatitis is less likely.

Recurrent oral infection is more common with HSV-1 infections than with HSV-2. Symptoms typically progress in a series of eight stages:

1. Latent (weeks to months incident-free): The remission period; After initial infection, the viruses move to sensory nerve ganglia (trigeminal ganglion), where they reside as lifelong, latent viruses. Asymptomatic shedding of contagious virus particles can occur during this stage.

2. Prodromal (day 0–1): Symptoms often precede a recurrence. Symptoms typically begin with tingling (itching) and reddening of the skin around the infected site. This stage can last from a few days to a few hours preceding the physical manifestation of an infection and is the best time to start treatment.

3. Inflammation (day 1): Virus begins reproducing and infecting cells at the end of the nerve. The healthy cells react to the invasion with swelling and redness displayed as symptoms of infection.

4. Pre-sore (day 2–3): This stage is defined by the appearance of tiny, hard, inflamed papules and vesicles that may itch and are painfully sensitive to touch. In time, these fluid-filled blisters form a cluster on the lip (labial) tissue, the area between the lip and skin (vermilion border), and can occur on the nose, chin, and cheeks.

5. Open lesion (day 4): This is the most painful and contagious of the stages. All the tiny vesicles break open and merge to create one big, open, weeping ulcer. Fluids are slowly discharged from blood vessels and inflamed tissue. This watery discharge is teeming with active viral particles and is highly contagious. Depending on the severity, one may develop a fever and swollen lymph glands under the jaw.

6. Crusting (day 5–8): A honey/golden crust starts to form from the syrupy exudate. This yellowish or brown crust or scab is not made of active virus but from blood serum containing useful proteins such as immunoglobulins. This appears as the healing process begins. The sore is still painful at this stage, but, more painful, however, is the constant cracking of the scab as one moves or stretches their lips, as in smiling or eating. Virus-filled fluid will still ooze out of the sore through any cracks.

7. Healing (day 9–14): New skin begins to form underneath the scab as the virus retreats into latency. A series of scabs will form over the sore (called Meier Complex), each one smaller than the last. During this phase irritation, itching, and some pain are common.

8. Post-scab (12–14 days): A reddish area may linger at the site of viral infection as the destroyed cells are regenerated. Virus shedding can still occur during this stage.

The recurrent infection is thus often called "herpes simplex labialis". Rare reinfections occur inside the mouth ("intraoral HSV stomatitis") affecting the gums, alveolar ridge, hard palate, and the back of the tongue, possibly accompanied by "herpes labialis".

A lesion caused by herpes simplex can occur in the corner of the mouth and be mistaken for angular cheilitis of another cause. Sometimes termed "angular herpes simplex". A cold sore at the corner of the mouth behaves similarly to elsewhere on the lips. Rather than utilizing antifungal creams, angular herpes simplex is treated in the same way as a cold sore, with topical antiviral drugs.

A herpetic whitlow is a lesion (whitlow) on a finger or thumb caused by the herpes simplex virus. It is a painful infection that typically affects the fingers or thumbs. Occasionally infection occurs on the toes or on the nail cuticle. Herpes whitlow can be caused by infection by HSV-1 or HSV-2. HSV-1 whitlow is often contracted by health care workers that come in contact with the virus; it is most commonly contracted by dental workers and medical workers exposed to oral secretions. It is also often observed in thumb-sucking children with primary HSV-1 oral infection (autoinoculation) prior to seroconversion, and in adults aged 20 to 30 following contact with HSV-2-infected genitals. Symptoms of herpetic whitlow include swelling, reddening and tenderness of the skin of infected finger. This may be accompanied by fever and swollen lymph nodes. Small, clear vesicles initially form individually, then merge and become cloudy. Associated pain often seems large relative to the physical symptoms. The herpes whitlow lesion usually heals in two to three weeks. It may reside in axillary sensory ganglia to cause recurrent herpetic lesions on that arm or digits.

Gingivostomatitis symptoms in infants may wrongly be dismissed as teething. "Coincidentally, primary tooth eruption begins at about the time that infants are losing maternal antibody protection against the herpes virus. Also, reports on teething difficulties have recorded symptoms which are remarkably consistent with primary oral herpetic infection such as fever, irritability, sleeplessness, and difficulty with eating." "Younger infants with higher residual levels of antibodies would experience milder infections and these would be more likely to go unrecognized or be dismissed as teething difficulty."

Gingivostomatitis must also be differentiated from herpangina, another disease that also commonly causes ulcers in the oral cavity of children, but is caused by the Coxsackie A virus rather than a herpes virus. In herpangina, ulcers are usually isolated to the soft palate and anterior pillar of the mouth. In herpetic gingivostomatitis, lesions can be found in these locations, but they are almost always accompanied by ulcerations on the gums, lips, tongue or buccal mucosa and/or by hyperemia, hypertrophy or hemorrhage of the gums.

In children the primary source of infection is the orofacial area, and it is commonly inferred that the virus (in this case commonly HSV-1) is transferred by the cutting, chewing or sucking of fingernail or thumbnail.

In adults, it is more common for the primary source to be the genital region, with a corresponding preponderance of HSV-2. It is also seen in adult health care workers such as dentists because of increased exposure to the herpes virus.

Contact sports are also a potential source of infection with herpetic whitlows.

Differences between the conditions chancre and chancroid:

- Chancre is a lesion typical of infection with the bacterium that causes syphilis, Treponema pallidum

- Chancroid is a lesion typical of infection with the bacterium Haemophilus ducreyi

- Chancres are typically painless, whereas chancroid are typically painful

- Chancres are typically single, whereas chancroid are typically multiple

- Chancres cause regional bilateral lymph node enlargement, whereas chancroid cause regional unilateral lymph node enlargement

- Chancres typically exude serum, whereas chancroid typically have a grey or yellow purulent exudate

- Chancres have a hard (indurated) base with sloping edges, whereas chancroid have a soft base with undermined edges

- Chancres heal spontaneously within three to six weeks, even in the absence of treatment

- Chancres can occur in the pharynx as well as on the genitals. Not to be confused with condyloma lata, which is seen in secondary syphilis

A chancre ( ) is a painless ulceration (sore) most commonly formed during the primary stage of syphilis. This infectious lesion forms approximately 21 days after the initial exposure to "Treponema pallidum", the gram-negative spirochaete bacterium yielding syphilis. Chancres transmit the sexually transmissible disease of syphilis through direct physical contact. These ulcers usually form on or around the anus, mouth, penis, and vagina. Chancres may diminish between four and eight weeks without the application of medication.

Chancres, as well as being painless ulcerations formed during the primary stage of syphilis, are associated with the African trypanosomiasis sleeping sickness, surrounding the area of the tsetse fly bite.

Symptoms can include:

- First signs – small red erosions on the glans

- Redness of the foreskin

- Redness of the penis

- Other rashes on the head of the penis

- Foul smelling discharge

- Painful foreskin and penis

VVS is characterized by severe pain with attempted penetration of the vaginal orifice and complaints of tenderness with pressure within the vulval vestibule. Usually there are no reports of pain with pressure to other surrounding areas of the vulva. The feelings of irritation and burning can persist for hours or days following sexual activity, engendering a sense of hopelessness and depression. VVS also can often cause dyspareunia.

The pain may be provoked by contact with an object, such as with the insertion of a tampon or penis or with the pressure from sitting on a bicycle seat, "provoked vestibulodynia", or it may be constant, as in the case of unprovoked, generalized vestibulodynia. Some women have had pain since their first penetration (primary vulvar vestibulitis) while some have had it after a period of time with pain-free penetration (secondary vulvar vestibulitis).

Relationship problems often occur as the result of chronic frustration, disappointment, and depression associated with the condition.

Recurrent bouts of balanitis may cause scarring of the preputial orifice; the reduced elasticity may lead to pathologic phimosis.

The symptoms of urethritis can include pain or a burning sensation upon urination (dysuria), a white/cloudy discharge and a feeling that one needs to pass urine frequently. For men, the signs and symptoms are discharge from the penis, burning or pain when urinating, itching, irritation, or tenderness. In women, the signs and symptoms are discharge from vagina, burning or pain when urinating, anal or oral infections, abdominal pain, or abnormal vaginal bleeding, which may be an indication that the infection has progressed to Pelvic Inflammatory Disease.

NGU is transmitted by touching the mouth, penis, vagina or anus by penis, vagina or anus of a person who has NGU.

NGU is more common in men than women. Men may have a discharge (strange liquid) from the penis, pain when urinating, and itching, irritation or tenderness around the opening of the penis. Women might not have any symptoms and may not know they have NGU until severe problems occur. Women might have discharge from the vagina, burning or pain when urinating, pain in the abdominal (stomach) area, or bleeding from the vagina that is not from a monthly period. (This may be an sign that NGU has become worse and turned into Pelvic Inflammatory Disease, or PID).

Signs and symptoms of candidiasis vary depending on the area affected. Most candidal infections result in minimal complications such as redness, itching, and discomfort, though complications may be severe or even fatal if left untreated in certain populations. In healthy (immunocompetent) persons, candidiasis is usually a localized infection of the skin, fingernails or toenails (onychomycosis), or mucosal membranes, including the oral cavity and pharynx (thrush), esophagus, and the genitalia (vagina, penis, etc.); less commonly in healthy individuals, the gastrointestinal tract, urinary tract, and respiratory tract are sites of candida infection.

In immunocompromised individuals, "Candida" infections in the esophagus occur more frequently than in healthy individuals and have a higher potential of becoming systemic, causing a much more serious condition, a fungemia called candidemia. Symptoms of esophageal candidiasis include difficulty swallowing, painful swallowing, abdominal pain, nausea, and vomiting.

Thrush is commonly seen in infants. It is not considered abnormal in infants unless it lasts longer than a few weeks.

Infection of the vagina or vulva may cause severe itching, burning, soreness, irritation, and a whitish or whitish-gray cottage cheese-like discharge. Symptoms of infection of the male genitalia (balanitis thrush) include red skin around the head of the penis, swelling, irritation, itchiness and soreness of the head of the penis, thick, lumpy discharge under the foreskin, unpleasant odour, difficulty retracting the foreskin (phimosis), and pain when passing urine or during sex.

Common symptoms of gastrointestinal candidiasis in healthy individuals are anal itching, belching, bloating, indigestion, nausea, diarrhea, gas, intestinal cramps, vomiting, and gastric ulcers. Perianal candidiasis can cause anal itching; the lesion can be erythematous, papular, or ulcerative in appearance, and it is not considered to be a sexually transmissible disease. Abnormal proliferation of the candida in the gut may lead to dysbiosis. While it is not yet clear, this alteration may be the source of symptoms generally described as the irritable bowel syndrome, and other gastrointestinal diseases.

Vulvar vestibulitis syndrome (VVS), vestibulodynia, or simply vulvar vestibulitis, is vulvodynia localized to the vulvar region. It tends to be associated with a highly localized "burning" or "cutting" type of pain. Until recently, "vulvar vestibulitis" was the term used for localized vulvar pain: the suffix "-itis" would normally imply inflammation, but in fact there is little evidence to support an inflammatory process in the condition. "Vestibulodynia" is the term now recognized by the International Society for the Study of Vulvovaginal Disease.

Vulvar Vestibulitis Syndrome (VVS) is the most common subtype of vulvodynia that affects premenopausal women. The syndrome has been cited as affecting about 10% to 15% of women seeking gynecological care.

Posthitis (pronounced pos-THI-tis) is the inflammation of the foreskin (prepuce) of the human penis. It is characterised by swelling and redness on the skin and it may be accompanied by a smelly discharge.

The term posthitis comes from the Greek "posthe", meaning foreskin, and "-itis", meaning inflammation.

Nongonococcal urethritis (NGU) is an inflammation of the urethra that is not caused by gonorrheal infection.

For treatment purposes, doctors usually classify infectious urethritis in two categories: gonococcal urethritis, caused by gonorrhea, and nongonococcal urethritis (NGU).

LGV may begin as a self-limited painless genital ulcer that occurs at the contact site 3–12 days after infection. Women rarely notice a primary infection because the initial ulceration where the organism penetrates the mucosal layer is often located out of sight, in the vaginal wall. In men fewer than 1/3 of those infected notice the first signs of LGV. This primary stage heals in a few days. Erythema nodosum occurs in 10% of cases.

Posthitis can have infectious causes such as bacteria or fungi, or non-infectious causes such as contact dermatitis or psoriasis. The inflammation may be caused by irritants in the environment. Common causative organisms include candida, chlamydia, and gonorrhea. The cause must be properly diagnosed before a treatment can be prescribed. A common risk factor is diabetes.

Posthitis can lead to phimosis, the tightening of the foreskin which makes it difficult to retract over the glans. Posthitis can also lead to superficial ulcerations and diseases of the inguinal lymph nodes.

Symptoms include sudden fever with sore throat, headache, loss of appetite, and often neck pain. Within two days of onset an average of four or five (but sometimes up to twenty) 1 to 2 mm diameter grayish lumps form and develop into vesicles with red surrounds, and over 24 hours these become shallow ulcers, rarely larger than 5 mm diameter, that heal in one to seven days. These lesions most often appear on the tonsillar pillars (adjacent to the tonsils), but also on the soft palate, tonsils, uvula, or tongue.

A small number of lesions (usually 2 - 6) form in the back area of the mouth, particularly the soft palate or tonsillar pillars. The lesions progress initially from red macules to vesicles and lastly to ulcerations which can be 2 – 4 mm in size.

The clinical manifestation of LGV depends on the site of entry of the infectious organism (the sex contact site) and the stage of disease progression.

- Inoculation at the mucous lining of external sex organs (penis and vagina) can lead to the inguinal syndrome named after the formation of buboes or abscesses in the groin (inguinal) region where draining lymph nodes are located. These signs usually appear from 3 days to a month after exposure.

- The rectal syndrome arises if the infection takes place via the rectal mucosa (through anal sex) and is mainly characterized by proctocolitis symptoms.

- The pharyngeal syndrome is rare. It starts after infection of pharyngeal tissue, and buboes in the neck region can occur.

Candidiasis may be divided into these types:

- Mucosal candidiasis

- Oral candidiasis (thrush, oropharyngeal candidiasis)

- Pseudomembranous candidiasis

- Erythematous candidiasis

- Hyperplastic candidiasis

- Denture-related stomatitis — "Candida" organisms are involved in about 90% of cases

- Angular cheilitis — "Candida" species are responsible for about 20% of cases, mixed infection of "C. albicans" and "Staphylococcus aureus" for about 60% of cases.

- Median rhomboid glossitis

- Candidal vulvovaginitis (vaginal yeast infection)

- Candidal balanitis — infection of the glans penis, almost exclusively occurring in uncircumcised males

- Esophageal candidiasis (candidal esophagitis)

- Gastrointestinal candidiasis

- Respiratory candidiasis

- Cutaneous candidiasis

- Candidial folliculitis

- Candidal intertrigo

- Candidal paronychia

- Perianal candidiasis, may present as pruritus ani

- Candidid

- Chronic mucocutaneous candidiasis

- Congenital cutaneous candidiasis

- Diaper candidiasis: an infection of a child's diaper area

- Erosio interdigitalis blastomycetica

- Candidial onychomycosis (nail infection) caused by "Candida"

- Systemic candidiasis

- Candidemia, a form of fungemia which may lead to sepsis

- Invasive candidiasis (disseminated candidiasis) — organ infection by "Candida"

- Chronic systemic candidiasis (hepatosplenic candidiasis) — sometimes arises during recovery from neutropenia

- Antibiotic candidiasis (iatrogenic candidiasis)