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STD
Definition STI
(Sexually transmitted infection Disease)
> Sexually transmitted infections (STIs) are infections transmitted mainly through sexual contact that cause sexually transmitted diseases (STDs).
They are the main causes of infertility , PID, ectopic pregnancy, cancer and congenital infections.
They impose a heavy health economic burden on especially developing countries due to mortality and morbidity, increasing drug resistance, and social stigma.
There are at least 30 known bacterial, viral and parasitic pathogens in this category.
1\ Neisseria gonorrhoeae
> The causative agent of gonorrhea, the attack rate is high in sexually active women aged 15-19 and men aged 20-24. The probability of transmission is 40-60% from an infected man to a woman during unprotected sex. 20% chance of transmission in an oral contact.
Clinical symptoms: Clinical syndromes of infection including: urethritis (men), cervicitis (women), PID, proctocolitis and anal gonorrhea, salpingitis and miscarriage (first 3 months of pregnancy), premature birth, eye infection and perinatal death (third month of pregnancy)
Systemic symptoms: gonococcal arthritis and diffuse gonococcal infection if bacteria enters the blood.
There is a possibility of simultaneous infection with Chlamydia trachomatis (more than 40%) and HIV.
2\ Chlamydia trachomatis
> It causes urethritis (men), cervicitis, salpingitis, endometritis and PID (women) and proctitis and lymphogranuloma venereum (LGV) in both sexes.
Untreated infection reduces the level of fertility in both sexes, chronic pelvic pain, EP and neonatal infection.
3\ Hemophilus ducreyi
It causes genital ulcers (chancroid), which increases the risk of HIV infection.
4\ Klebsiella granulomatis
> It causes inguinal granuloma (donovanosis).
Is common in North Africa, certain tribes in Australia and East India.
It causes painless sores in the genital area.
5\ granuloma inguinale
granuloma inguinale is a chronic bacterial infection. granuloma inguinale is characterized by intracellular inclusions in macrophages referred to as donovan bodies. granuloma inguinale usually affects the skin and mucous membranes in the genital region, where it results in nodular lesions that evolve into ulcers
6\ Treponema pallidum
> The agent of syphilis, is transmitted sexually (50%) and nonsexually (blood transfusion or laboratory) through damaged skin or mucous membrane.
MSM & HIV patients are at high risk of infection.
have different clinical symptoms depending on the pathological stage (primary, secondary, final, delayed)
Primary syphilis (chancre): occurs at the site of infection (genital organ, anus, mouth, cervix) and recovers after 3-6 weeks (spontaneously or with treatment).
The second stage of syphilis: occurs at the same time as the chancre lesions heal or a few weeks later. Symptoms include skin involvement, generalized lymphadenopathy, fever and systemic symptoms, and with less prevalence of meningitis, hepatitis, neuropathy and gastrointestinal tract involvement.
Delayed syphilis: usually without clinical signs and symptoms, including two stages: early (less than 1 year) and late (more than a year).
Third stage syphilis: rare, may appear 10-30 years after initial infection. Involvement of various organs including: CNS (25% of patients have CNS infection) and cardiovascular (10% will have cardiovascular symptoms after 10-40 years), skin necrosis, skeletal system, lung, stomach, etc.
Symptoms of syphilis during pregnancy (usually in the fourth month) include stillbirth, abortion, perinatal infection and death, and weight loss.
7\ Mycoplasma, Trichomonas vaginalis
> Ureoplasma and Mycoplasma genitalium: They cause urethritis and bacterial vaginitis.
Trichomonas vaginalis: trichomoniasis with symptoms of vulvovaginitis and a range of consequences including premature birth, PID, etc. Men are usually asymptomatic.
8\ Herpes simplex virus (HSV)
1\ Both types of HSV1 and HSV2 cause lesions both in the oral and genital areas. The probability of recurrence of type 2 in the genital area is higher (90% versus 55% in the first year).
2\ More than 80% of women with primary genital herpes have involvement of the urinary tract and cervix with symptoms of pain, frequent urination, vaginal and urinary discharge, and inguinal lymphadenopathy. Other symptoms include urethritis in men and women, genital ulcers and proctitis.
8\ HPV
> Types 6 and 11 are associated with anal genital warts in 90% of cases.
Types 16, 18, 31, 33, 45 are related to cervical cancer. (70% of cases type 16 and 18)
9\ Other infections
> Intestinal pathogens (Camplobacter, Shigella, Salmonella, Entamoeba, Giardia), Hepatitis A and Candida may also be transmitted through sexual contact, especially in homosexual men
Epidemiology of sexually transmitted infections
> It is estimated that an average of one million people around the world get sexually transmitted infections every day. Most cases occur in sub-Saharan Africa, Latin America, and the eastern Pacific.
> 50% of these infections occur in the age group of 15-24 years. (While HIV is common in the population over 25 years old).
The most common causes are: Chlamydia trachomatis, HPV, Trichomonas vaginalis and Neisseria gonorrhoea.
> In developing countries, sexually transmitted infections, after pregnancy and childbirth are the second cause of loss of healthy life in women aged 15-45 years. (In men of this age group, urinary infections and HIV account for 15% of healthy life loss).
> Chlamydia is the most common sexually transmitted infection in the whole world with a frequency of 89 million cases per year. Its prevalence in American women and men is increasing (5.8 per 100,000 in 2006).
> Gonococcal infections are still prevalent worldwide. In a South African study in 2007, among men with urinary tract discharge, the most common causes were gonorrhea (62.3%), chlamydia (19.3%) and trichomonas vaginalis (3%).
Epidemiology of sexually transmitted infections in EMRO region
> Every year, about 10 million new cases of urinary tract infections occur in the EMRO region. The prevalence of sexually transmitted infections in this region is unknown, but it is much higher in at-risk populations such as vulnerable women and MSM than in the general population.
HSV2 is the most important cause of genital ulcers worldwide. The EMRO region data is not valid in this regard. In a study in Saudi Arabia, a prevalence of 27% was reported.
> According to the 2008 WHO report, the prevalence of syphilis in the EMRO region was about 1%. which is one of the main public health concerns due to its harmful effects during pregnancy.
Information on Trichomonas vaginalis infection (the most common non-viral sexually transmitted infection) is very scarce due to the lack of screening programs and the poor quality of the reporting system. Estimates indicate an increase in the rate of this infection in the EMRO region. Its prevalence was reported in 29.9% of women in the outpatient clinic in Yemen, 12% in Jordanian gynecological diseases and 9.9% in vulnerable women in Egypt.
> The prevalence of gonococcal infections in MSM in Cairo was 8.8%, vulnerable women 7.7%, and injecting drug users 2.7%, and 2% in maternity clinics.
Epidemiology of sexually transmitted infections in Iran
> According to the instructions of the sexually transmitted diseases surveillance system in the country, all providers of health care services to sexually transmitted infections patients, including health-treatment centers, hospitals, private practices, etc., are required to report current sexually transmitted infections (Probable and definite primary and secondary syphilis, non-vesicular genital ulcer, definite gonorrhea and chlamydia, ductal discharge).
> The sensitivity of reporting sexually transmitted diseases is 25% on average. (Studies of Bandar Abbas and Dareh Gaz)
> Reporting cases in men is low and women have an increasing slope.
> According to the report of the Blood Transfusion Organization, the prevalence of hepatitis B and syphilis in blood donors is decreasing.
Epidemiology of sexually transmitted infections in Iran, results of studies
> There are limited studies about the prevalence and incidence of sexually transmitted infections in the country.
> The result of a study in 2013 (1390 solar year) in four cities of Tehran, Shiraz, Kerman and Babol showed that about 85.14% of women and 36.22% of men had a history of having at least one or more of the symptoms of sexually transmitted infections during their lifetime. Itching in women (57.4%) and burning in the genital area (23.6%) in men were the most cases, the most affected age groups were 25-30 years (men) and 30-40 years (women), 6.6% of people who had a history of sexually transmitted infection symptoms had self-medicated, and 3.35% had not taken any action, and a total of 86% of the patients had referred to the private sector for services.
> Investigation of drug resistance has also been limited in the country. In the study of Zahedan city (2010), it was found that 50% of the samples show resistance to ciprofloxacin on gonococcal samples.
