**8.1 Epidemiology**

Globally, chancroid is the most common cause of genital ulcer disease in regions where the disease is endemic. WHO estimates the annual global incidence to be about 6 million cases. Chancroid occurs in parts of Africa, south-east Asia and the Caribbean where it accounts for 23-56% of genital ulcer disease. Chancroid is more common in men than women and more common in areas where HIV prevalence is high (>8%). The incidence of chancroid is much lower in developed countries and sporadic outbreaks there are associated with travel, prostitution, and drug use. Chancroid, as are all genital ulcer producing STIs, is a risk factor for HIV transmission.

#### **8.2 Clinical manifestations**

After an incubation period of several days to two weeks, a tender erythematous papule develops at the site of inoculation which progresses to a pustular stage. The pustle ruptures within 2-3 days to form a painful genital ulcer with soft edges. Chancroid ulcerative lesions vary from 3-50 mm across but are typically 10-20 mm. Chancroid ulcers can be irregular, round, or oval in shape, are sharply circumscribed with an undermined edge, and contain a grey or yellow purulent exudate. Lesions will have a surrounding cutaneous erythema. One half of men have only a single ulcer and lesions typically appear on the penis: penile shaft, coronal sulcus, prepuce, urethral meatus, and glans. In women infection is often subclinical. Women have multiple ulcers more frequently than men that may merge to form large ulcers. Ulcers in women occur on the fourchette, labia majora, labia minora, cervix, perianal region, and inner thighs. "Kissing ulcers" may develop on the skin surfaces apposing the initial ulcer. Women may also experience dysuria and dyspareunia. Rectal sores in men or women may bleed or cause pain during defecation. Buboes, swelling of the inguinal lymph nodes, occur in one third to one half of infected individuals 1-2 weeks after the ulcers form and these may rupture, producing draining abscesses. The development of buboes is a more

Sexually Transmitted Infections in the Tropics 473

Genital human papillomavirus is considered to be one of the most prevalent STIs in the world. It is estimated that more than 50% of sexually active individuals become infected at least once in their life. WHO estimates that 14.3% of women in developing regions and 10.3% of women in developed regions with normal cervical cytology are infected with HPV. Incidence of HPV in women increases significantly with severity of abnormal cervical cytology. Prevalence of HPV reaches to greater than 70% in women with cervical cancer.

Asymptomatic genital HPV infection is common and usually self-limited. Seventy percent of infections are gone in 1 year, and 90% in 2 years. The most common symptom of genital HPV infection is genital warts, also known as condylomata acuminata. Genital warts appear as a small white bump or groups of bumps in the genital area. Genital warts are usually flat, papular, or pedunculated growths. However, they can be small or large, raised or flat. Genital warts are usually themselves asymptomatic, but can sometimes be painful and pruritic, depending on the size and anatomic location. Growths commonly occur around the introitus in women, under the foreskin of the uncircumcised penis, and on the shaft of the circumcised penis. Genital warts can also be found in or on the cervix, vagina, urethra, perineum, perianal skin, and scrotum. Intra-anal warts are most often observed in individuals who have had receptive anal intercourse, but may be present in men or women

The correlation between persistent HPV infection and cervical cancer has been well established. Cervical cancer is the 2nd most common cancer among women, worldwide. Eighty-six percent of these cases occur in developing countries, making up 13% of the world female population. There is now increasing evidence linking HPV to anogenital cancers other than cervical cancer. These include anal, vulvar, vaginal, penile, and head and neck cancers. Anal cancer occurs rarely with about 99,000 cases in 2002, sixty percent of cases occurring in women and 40% in men. This type of cancer is more prevalent in populations of men who have sex with men and HIV-positive populations. Vulvar cancers make up about 3% of the gynecological cancers, with 40% of them occurring in developing countries. The majority of these cases occurring in the developed world suggest that HPV screening may not be an effective preventative method. Vaginal cancers make up 2% of gynecological cancers, with a majority of vaginal cancers (68%) occurring in developing countries. Penile cancer represents 0.5% of cancers in men. In western countries, incidence if penile cancer in men is less than 1 per 100,000, however, this rate increases in Latin America, India, and Thailand. Two-thirds of oral cancers occur in developing countries and about 15-20% of oral cancers are associated with HPV infection. Growing evidence suggests that HPV-related

The presence of genital warts is a straight forward method for diagnosis of HPV. However, in the case of asymptomatic infections, there is no general diagnostic test used to screen normal patients for HPV. The Papanicolaou test (Pap smear or Pap test) is a cytological examination of cervical tissue sample that is used to screen for cervical cancer or

oral pharyngeal cancers are associated with the practice of oral sex.

**9.1 Epidemiology** 

**9.2 Clinical manifestations** 

with no history of anal sexual contact.

**9.3 Health sequelae** 

**9.4 Diagnosis** 

common occurrence in men than women. Buboes are painful, tender, and fluctuant with underlying erythema, and are typically unilateral. Supperative adenopathy is almost pathognomonic for chancroid. The skin over the bubo does not become thickened and edematous or show furrows as in the adenopathy of LGV. Chancroid can also spread via self inoculation to other anatomical sites. Chancroid in HIV-infected patients may produce a larger number of ulcers, atypical ulcers, extra-genital lesions, and longer lasting ulcers even with treatment.
