Researchers had hoped that nonoxynol-9, a vaginal microbicide would help decrease STI risk. Trials, however, have found it ineffective and it may put women at a higher risk of HIV infection.

The Centers for Disease Control and Prevention strategies for reducing STD risk include: vaccination, mutual monogamy, reducing the number of sexual partners and abstinence.

The most effective way to prevent sexual transmission of STIs is to avoid contact of body parts or fluids which can lead to transfer with an infected partner. Not all sexual activities involve contact: cybersex, phonesex or masturbation from a distance are methods of avoiding contact. Proper use of condoms reduces contact and risk. Although a condom is effective in limiting exposure, some disease transmission may occur even with a condom.

Both partners can get tested for STIs before initiating sexual contact, or before resuming contact if a partner engaged in contact with someone else. Many infections are not detectable immediately after exposure, so enough time must be allowed between possible exposures and testing for the tests to be accurate. Certain STIs, particularly certain persistent viruses like HPV, may be impossible to detect with current medical procedures.

Some treatment facilities utilize in-home test kits and have the person return the test for follow-up. Other facilities strongly encourage that those previously infected return to ensure that the infection has been eliminated. Novel strategies to foster re-testing have been the use of text messaging and email as reminders. These types of reminders are now used in addition to phone calls and letters. After obtaining a sexual history, a healthcare provider can encourage risk reduction by providing prevention counseling. Prevention counseling is most effective if provided in a nonjudgmental and empathetic manner appropriate to the person's culture, language, gender, sexual orientation, age, and developmental level. Prevention counseling for STIs is usually offered to all sexually active adolescents and to all adults who have received a diagnosis, have had an STI in the past year, or have multiple sex partners.

USPSTF recommends high-intensity behavioral counseling for all sexually active adolescents and for adults at increased risk for STIs. Such interactive counseling, which can be resource intensive, is directed at a person's risk, the situations in which risk occurs, and the use of personalized goal-setting strategies.

As with most sexually transmitted diseases, the risk of infection can be reduced significantly by the correct use of condoms and can be removed almost entirely by limiting sexual activities to a mutually monogamous relationship with an uninfected person.

Those previously infected are encouraged to return for follow up care to make sure that the infection has been eliminated. In addition to the use of phone contact, the use of email and text messaging have been found to improve the re-testing for infection.

As of 2010, injectable ceftriaxone is one of the few effective antibiotics. This is typically given in combination with either azithromycin or doxycycline. As of 2015 and 2016 the CDC and WHO only recommends both ceftriaxone and azithromycin. Because of increasing rates of antibiotic resistance local susceptibility patterns must be taken into account when deciding on treatment.

The CDC recommends that sexually active men who have sex with men be tested at least yearly. The USPSTF also recommends screening among those at high risk.

Syphilis is a notifiable disease in many countries, including Canada the European Union, and the United States. This means health care providers are required to notify public health authorities, which will then ideally provide partner notification to the person's partners. Physicians may also encourage patients to send their partners to seek care. Several strategies have been found to improve follow-up for STI testing, including email and text messaging as reminders of appointments.

Congenital syphilis in the newborn can be prevented by screening mothers during early pregnancy and treating those who are infected. The United States Preventive Services Task Force (USPSTF) strongly recommends universal screening of all pregnant women, while the World Health Organization recommends all women be tested at their first antenatal visit and again in the third trimester. If they are positive, it is recommend their partners also be treated. Congenital syphilis is still common in the developing world, as many women do not receive antenatal care at all, and the antenatal care others receive does not include screening. It still occasionally occurs in the developed world, as those most likely to acquire syphilis (through drug use, etc.) are least likely to receive care during pregnancy. Several measures to increase access to testing appear effective at reducing rates of congenital syphilis in low- to middle-income countries. Point-of-care testing to detect syphilis appeared to be good although more research is needed to assess its effectiveness and into improving outcomes in mothers and babies.

"C. trachomatis" infection can be effectively cured with antibiotics. Guidelines recommend azithromycin, doxycycline, erythromycin, levofloxacin or ofloxacin. Agents recommended during pregnancy include erythromycin or amoxicillin.

An option for treating sexual partners of those with chlamydia or gonorrhea include patient-delivered partner therapy (PDT or PDPT), which is the practice of treating the sex partners of index cases by providing prescriptions or medications to the patient to take to his/her partner without the health care provider first examining the partner.

Following treatment people should be tested again after three months to check for reinfection.

Evidence from a randomized controlled trials for screening pregnant women who do not have symptoms for infection with trichomoniasis and treating women who test positive for the infection have not consistently shown a reduced risk of preterm birth. Further studies are needed to verify this result and determine the best method of screening. In the US, screening of pregnant women without any symptoms is only recommended in those with HIV as trichomonas infection is associated with increased risk of transmitting HIV to the fetus.

For sexually active women who are not pregnant, screening is recommended in those under 25 and others at risk of infection. Risk factors include a history of chlamydial or other sexually transmitted infection, new or multiple sexual partners, and inconsistent condom use. For pregnant women, guidelines vary: screening women with age or other risk factors is recommended by the U.S. Preventive Services Task Force (USPSTF) (which recommends screening women under 25) and the American Academy of Family Physicians (which recommends screening women aged 25 or younger). The American College of Obstetricians and Gynecologists recommends screening all at risk, while the Centers for Disease Control and Prevention recommend universal screening of pregnant women. The USPSTF acknowledges that in some communities there may be other risk factors for infection, such as ethnicity. Evidence-based recommendations for screening initiation, intervals and termination are currently not possible. For men, the USPSTF concludes evidence is currently insufficient to determine if regular screening of men for chlamydia is beneficial. They recommend regular screening of men who are at increased risk for HIV or syphilis infection.

In the United Kingdom the National Health Service (NHS) aims to:

1. Prevent and control chlamydia infection through early detection and treatment of asymptomatic infection;

2. Reduce onward transmission to sexual partners;

3. Prevent the consequences of untreated infection;

4. Test at least 25 percent of the sexually active under 25 population annually.

5. Retest after treatment.

The Jarisch-Herxheimer reaction, which is the response to the body after endotoxins are released by the death of harmful organisms in the human body, starts usually during the first day of antibiotic treatment. The reaction increases the person's body temperature, decreases the overall blood pressure (both systolic and diastolic levels), and results in leukopenia and rigors in the body. This reaction can occur during any treatment of spirochete diseases.

It is important to realize that syphilis can recur. An individual who has had the disease once, even if it has been treated, does not prevent the person from experiencing recurrence of syphilis. Individuals can be re-infected, and because syphilis sores can be hidden, it may not be obvious that the individual is infected with syphilis. In these cases, it is vital to become tested and treated immediately to reduce spread of the infection.

Treatment for both pregnant and non-pregnant women is usually with metronidazole, by mouth once. Caution should be used in pregnancy, especially in the first trimester. Sexual partners, even if they have no symptoms, should also be treated.

For 95-97% of cases, infection is resolved after one dose of metronidazole. Studies suggest that 4-5% of trichomonas cases are resistant to metronidazole, which may account for some “repeat” cases. Without treatment, trichomoniasis can persist for months to years in women, and is thought to improve without treatment in men. Women living with HIV infection have better cure rates if treated for 7 days rather than with one dose.

Topical treatments are less effective than oral antibiotics due to Skene's gland and other genitourinary structures acting as a reservoir.

There are many different forms on prevention of syphilis and other sexually transmitted diseases in general. Prevention of syphilis includes avoiding contact of bodily fluids with an infected person. This can be particularly difficult because syphilis is usually transmitted by people who are unaware that they have the disease because they do not have any visible sores or rashes that may denote having an infection in general. Being abstinent or having mutually monogamous sex with a person who is uninfected with any type of sexually transmitted disease is the greatest guarantee of not becoming infected with syphilis or any form of a sexually transmitted disease. Using latex condoms can however reduce the risk of obtaining syphilis. In order to prevent further contamination to other individuals, benzathine penicillin is given to any contacts. Washing, douching, or urinating cannot prevent the transmission of a sexually transmitted disease in general.

Individuals obtain syphilis through a variety of circumstances. In general, syphilis can be transmitted from individual to individual through direct contact with sores that are present on the external genitals, vagina, rectum, anus, lips, or mouth. Transmission can occur through any form of sexual contact, including vaginal, anal, and oral sex. In addition, women who are pregnant and infected with syphilis can transmit the disease onto their child as well. If transmission has occurred, it is important to check up immediately with a physician to avoid further damage.

Chancroid spreads in populations with high sexual activity, such as prostitutes. Use of condom, prophylaxis by azithromycin, syndromic management of genital ulcers, treating patients with reactive syphilis serology are some of the strategies successfully tried in Thailand.

The CDC recommendation for chancroid is a single oral dose (1 gram) of azithromycin, or a single IM dose of ceftriaxone, or oral erythromycin for seven days.

Abscesses are drained.

"H. ducreyi" is resistant to sulfonamides, tetracyclines, penicillins, chloramphenicol, ciprofloxacin, ofloxacin, trimethoprim and aminoglycosides. Recently, several erythromycin resistant isolates have been reported.

Treatment failure is possible with HIV co-infection and extended therapy is sometimes required.

Some vertically transmitted infections, such as toxoplasmosis and syphilis, can be effectively treated with antibiotics if the mother is diagnosed early in her pregnancy. Many viral vertically transmitted infections have no effective treatment, but some, notably rubella and varicella-zoster, can be prevented by vaccinating the mother prior to pregnancy.

If the mother has active herpes simplex (as may be suggested by a pap test), delivery by Caesarean section can prevent the newborn from contact, and consequent infection, with this virus.

IgG antibody may play crucial role in prevention of intrauterine infections and extensive research is going on for developing IgG-based therapies for treatment and vaccination.

Each type of vertically transmitted infection has a different prognosis. The stage of the pregnancy at the time of infection also can change the effect on the newborn.

, genital herpes cannot be cured. There are, however, some medications that can shorten outbreaks including acyclovir, valacyclovir, and famciclovir.

Acyclovir is an antiviral medication and reduces the pain and the number of lesions in the initial case of genital herpes. Furthermore, it decreases the frequency and severity of recurrent infections. It comes in capsules, tablets, suspension, injection, powder for injection, and ointment. The ointment is used topically and it decreases pain, reduces healing time, and limits the spread of the infection.

Valacyclovir once in the body, it is converted to acyclovir. It helps relieve the pain and discomfort and the sores heal faster. It only comes in caplets and its advantage is that it has a longer duration of action than acyclovir. An example usage is by mouth twice per day for 10 days for primary lesion, and twice per day for 3 days for a recurrent episode.

Famciclovir is another antiviral drug that belongs to the same class. Famciclovir is a prodrug that is converted to penciclovir in the body. The latter is the one active against the viruses. It has a longer duration of action than acyclovir and it only comes in tablets.

Antiretroviral treatment among people with HIV whose CD4 count ≤ 550 cells/µL is a very effective way to prevent HIV infection of their partner (a strategy known as treatment as prevention, or TASP). TASP is associated with a 10 to 20 fold reduction in transmission risk. Pre-exposure prophylaxis (PrEP) with a daily dose of the medications tenofovir, with or without emtricitabine, is effective in a number of groups including men who have sex with men, couples where one is HIV positive, and young heterosexuals in Africa. It may also be effective in intravenous drug users with a study finding a decrease in risk of 0.7 to 0.4 per 100 person years.

Universal precautions within the health care environment are believed to be effective in decreasing the risk of HIV. Intravenous drug use is an important risk factor and harm reduction strategies such as needle-exchange programs and opioid substitution therapy appear effective in decreasing this risk.

Currently, there is no licensed vaccine for HIV or AIDS. The most effective vaccine trial to date, RV 144, was published in 2009 and found a partial reduction in the risk of transmission of roughly 30%, stimulating some hope in the research community of developing a truly effective vaccine. Further trials of the RV 144 vaccine are ongoing.

If symptomatic, testing is recommended. The risk of contracting Micoplasma infection can be reduced by the following:

- Using barrier methods such as condoms

- Seeking medical attention if you are experiencing symptoms suggesting a sexually transmitted infection.

- Seeking medical attention after learning that a current or former sex partner has, or might have had a sexually transmitted infection.

- Getting a STI history from your current partner and insisting they be tested and treated before intercourse.

- Avoiding vaginal activity, particularly intercourse, after the end of a pregnancy (delivery, miscarriage, or abortion) or certain gynecological procedures, to ensure that the cervix closes.

- Abstinence

Testing peoples blood, including those who are pregnant, who do not have symptoms for HSV is not recommended. This is due to concerns of greater harm than benefit such as relationship problems in the setting of a high rate of tests that may be falsely positive.

Gardasil (sold by Merck & Co.) is a vaccine that protects against human papillomavirus types 6, 11, 16 and 18. Types 6 and 11 cause genital warts, while 16 and 18 cause cervical cancer. The vaccine is preventive, not therapeutic, and must be given before exposure to the virus type to be effective, ideally before the beginning of sexual activity. The vaccine is approved by the US Food and Drug Administration for use in both males and females as early as 9 years of age.

In the UK, Gardasil replaced Cervarix in September 2012 for reasons unrelated to safety. Cervarix had been used routinely in young females from its introduction in 2008, but was only effective against the high-risk HPV types 16 and 18, neither of which typically causes warts.

Podophyllin, podofilox and isotretinoin should not be used during pregnancy, as they could cause birth defects in the fetus.

Mycoplasmas have a triple-layered membrane and lack a cell wall. Commonly used antibiotics are generally ineffective because their efficacy is due to their ability to inhibit cell wall synthesis. Micoplasmas are not affected by penicillins and other antibiotics that act on the cell wall. The growth of micoplasmas in their host is inhibited by other broad-spectrum antibiotics. These broad-spectrum antibiotics inhibit the multiplication of the mycoplasma but does not kill them. Tetracyclines, macrolides, erythromycin, macrolides, ketolides, quinolones are used to treat mycoplasma infections. In addition to the penicillins, mycoplasmas are resistant to rifampicin. Mycoplasmas may be difficult to eradicate from human or animal hosts or from cell cultures by antibiotic treatment because of resistance to the antibiotic, or because it does not kill the mycoplasma cell. Mycoplasma cells are able to invade the cells of their hosts.

Three vaccines are available to prevent infection by some HPV types: Gardasil, Cervarix, and Gardasil 9. All protect against initial infection with HPV types 16 and 18, which cause most of the HPV-associated cancer cases. Gardasil also protects against HPV types 6 and 11, which cause 90% of genital warts. Gardasil is a recombinant quadrivalent vaccine, whereas Cervarix is bivalent, and is prepared from virus-like particles (VLP) of the L1 capsid protein. Gardasil 9 is nonavalent, it has the potential to prevent about 90% of cervical, vulvar, vaginal, and anal cancers. It can protect for HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. The latter five additional types cause up to 20% of cervical cancers, which were not previously covered beforehand.

The vaccines provide little benefit to women having already been infected with HPV types 16 and 18. For this reason, the vaccine is recommended primarily for those women not yet having been exposed to HPV during sex. The World Health Organization position paper on HPV vaccination clearly outlines appropriate, cost-effective strategies for using HPV vaccine in public sector programs.

The CDC recommends the vaccines be delivered in two shots, with an interval of at least 6 months between them, for those who are 11 to 12, and three doses for those who are older. In most countries, they are funded only for female use, but are approved for male use in many countries, and funded for teenage boys in Australia. The vaccine does not have any therapeutic effect on existing HPV infections or cervical lesions. In 2010, 49% of teenage girls in the US got the HPV vaccine.

Following studies suggesting that the vaccine is more effective in younger girls than in older teenagers, the United Kingdom, Switzerland, Mexico, the Netherlands and Quebec began offering the vaccine in a two-dose schedule for girls aged under 15 in 2014.

Cervical cancer screening recommendations have not changed for females who receive HPV vaccine. It remains a recommendation that women continue cervical screening, such as Pap smear testing, even after receiving the vaccine, since it does not prevent all types of cervical cancer.

Both men and women are carriers of HPV. The Gardasil vaccine also protects men against anal cancers and warts and genital warts.

Duration of both vaccines' efficacy has been observed since they were first developed, and is expected to be longlasting.

In December 2014, the FDA approved a nine-valent Gardasil-based vaccine, Gardasil 9, to protect against infection with the four strains of HPV covered by the first generation of Gardasil as well as five other strains responsible for 20% of cervical cancers (HPV-31, HPV-33, HPV-45, HPV-52, and HPV-58).