Sexually Transmitted Diseases: What They Are, Causes, Symptoms, Treatment & Types

What are Sexually Transmitted Diseases (STDs)?

The terms STD and STI are often used interchangeably. Technically,STI refers to an infection, whether or not it produces symptoms. 'STD' refers to the point at which the disease develops. Many people can carry and transmit STIs without ever reaching the disease stage.

According to the World Health Organisation (WHO), more than 30 bacteria, viruses, and parasites can be transmitted through sexual contact.

Bacterial and parasitic STIs respond well to the right treatment. Viral ones like HIV, herpes, HPV, and hepatitis B can be managed but not eliminated.

What are the Types of Sexually Transmitted Diseases?

The types of STIs based on the pathogen include:

How Common are STIs in India?

Although exact numbers are difficult to estimate, the actual prevalence of STIs in India is believed to be higher than the reported figures.

India has no mandatory national reporting for most STIs, so figures come from clinic-based studies rather than population surveillance. Some studies suggest that at any given time, about 6% of Indian adults have STIs.

Many infections are asymptomatic, and routine screening is not always carried out. Thus, a large number of cases may be undiagnosed or unreported.

What are the Symptoms of STIs?

Most STIs show no symptoms at all. When they do appear, the pattern varies by type. Across STI types, the most commonly reported symptoms include:

• Unusual Discharge: Abnormal discharge can be noticed from the penis, vagina, or rectum. The colour, consistency, and odour change with the specific infection.

• Pain or Burning on Urination: This symptom is common in gonorrhoea, chlamydia, and trichomoniasis.

• Sores, Ulcers, or Blisters: Painless sores are typical of syphilis. Painful blisters or ulcers are characteristic of herpes. Both variations can appear on the genitals, anus, or mouth.

• Rashes: Secondary syphilis causes a distinctive non-itchy rash on the palms and soles, while HPV causes warts. Acute HIV infection can cause a diffuse body rash.

• Pelvic or Abdominal Pain: In women, untreated chlamydia or gonorrhoea can progress to pelvic inflammatory disease, causing lower abdominal pain, fever, and painful sex.

Note: Chlamydia in women and trichomoniasis in men are asymptomatic in most cases. The only way to detect them is to get tested as prescribed by your healthcare professional.

You should also note that the absence of symptoms does not always mean the absence of infection. Sexually active people should get regular checkups and seek treatment if an STI is diagnosed.

What Are the Causes and Risk Factors of STIs?

STIs are caused by specific viruses, parasites, or bacteria that can spread through sexual contact. However, there are several risk factors that can increase the risk of contracting an STI:

• Unprotected Sexual Contact: Having vaginal, anal, or oral sex without a condom can increase the risk of developing an STI.

• Multiple Sexual Partners: Having multiple sexual partners can increase the risk of getting an STI.

• Existing STIs: If you have an untreated STI, it increases the risk of developing another.

• Sharing Needles: Contaminated needles can transmit STDs like hepatitis B and HIV.

• Mother-to-Child STI Transmission: Some STIs can be passed from a mother to the baby during pregnancy, delivery, and breastfeeding.

What are the Complications of STIs?

If left untreated, some STIs can affect other parts of the body and cause serious complications, such as:

• Infertility: Chlamydia and gonorrhoea that have spread to the upper reproductive tract can cause pelvic inflammatory disease (PID). This is the leading preventable cause of female infertility. In men, gonorrhoea-related epididymo-orchitis can impair sperm function.

• Cervical and Other Cancers: Persistent HPV infection directly causes virtually all cervical cancers and a significant proportion of throat, anal, and penile cancers.

• Pregnancy Complications: Congenital syphilis causes stillbirth and severe disability. Gonorrhoea and chlamydia can cause neonatal eye infections and pneumonia. Untreated HIV can be passed to the baby.

• AIDS: Untreated HIV progresses to AIDS, where immune function deteriorates to the point that the body can't fight common infections.

When Should I See My Healthcare Provider?

You should consult your healthcare provider if:

• You've had unprotected sex with a new or multiple partners.

• Unusual discharge, sores, blisters, rashes, or unexplained pain in the genital or anal area.

• Pain during urination or sex.

• A partner has been diagnosed with an STI.

• You're pregnant or planning a pregnancy and haven't been screened for STIs.

Note: The social stigma associated with venereal diseases is the main reason people don't get tested regularly. It is important to understand that STIs are medical conditions like any other, and testing is confidential. The earlier it's done, the simpler the treatment.

How are STIs Diagnosed?

There are different tests for each STD, and the right test depends on the patient's symptoms and predisposing factors.

How are STIs Treated?

The treatment plan for STIs depends on the pathogen. Bacterial and parasitic infections are curable; viral STIs are not, but they're manageable.

For bacterial STIs, antibiotics work when the right one is used. Syphilis responds to penicillin even at later stages, while chlamydia clears with a short oral course. However, treatment for gonorrhoea faces some challenges due to increasing antibiotic resistance. This points out the importance of early detection and proper medical care.

Viral STIs can be managed with timely treatment. For example, herpes can be managed with antivirals that reduce the frequency and severity of the outbreak.

STIs in Pregnancy

The risk of vertical STI transmission during pregnancy is often high. Thankfully, routine antenatal screening is standard in India and substantially reduces transmission when treatment starts early.

Antenatal care that includes STI screening isn't just good practice; it's one of the most effective interventions available to ensure STIs don’t pass on through vertical transmission.

What is the Prognosis for STIs?

Many people recover well when they receive an early diagnosis and treatment for a sexually transmitted infection. However, late diagnosis may increase the risk of long-term complications, such as infertility, chronic pelvic pain, and some types of cancer.

For curable bacterial STIs caught early, the prognosis is excellent, with full resolution and no lasting damage. However, if the infection has already caused long-term damage before you start treatment, it can complicate recovery.

For instance, Pelvic Inflammatory Disease (PID) that scars the fallopian tubes doesn't reverse after antibiotics clear the infection. Overall, the long-term recovery outcome depends on how early the infection is detected, not the STI itself.

The prognosis for viral STIs varies. HIV on effective ART carries near-normal life expectancy today, and herpes is lifelong but manageable.

How Can STIs Be Prevented?

Most STIs are extremely preventable when necessary precautions are taken:

• Use Condoms: Condoms, when used correctly, can substantially reduce transmission of most STIs.

• Vaccinate: The HPV vaccine protects against the high-risk strains that cause cervical cancer and is most effective before sexual debut. India's national immunisation programme covers vaccination for girls aged 9 to 14. Apart from HPV, hepatitis B vaccination is also included in the routine immunisation schedule across the country.

• Test Regularly: Since many STIs are asymptomatic, testing is the only reliable detection method. Sexually active people with new or multiple partners should get tested annually.

• Consider PrEP: Pre-exposure prophylaxis (PrEP) reduces HIV risk by about 99% when taken consistently. The preventive medicine is available in India and is recommended for high-risk groups.

Does Health Insurance Cover STIs?

While health insurance in India generally does not cover STDs, some health insurance plans may cover diagnostic costs and inpatient admissions for STI-related complications. However, routine outpatient STI screening isn't covered without an OPD benefit.

Meanwhile, HIV coverage under health insurance in India is expanding. Insurers are legally required to maintain medical confidentiality, which matters here given the stigma attached to an STI diagnosis.

How Much Health Insurance Coverage is Needed for STI Treatment?

For most curable bacterial STIs, a consultation and antibiotic course costs around ₹500 to ₹3,000. The overall cost of treatment can increase if hospitalisation is required.

Depending on the location and treatment requirements, a health insurance cover of ₹5–₹10 lakh may be adequate to cover hospitalisation expenses arising from complications due to STIs.

People requiring long-term HIV treatment can opt for a higher sum insured. While government ART treatment through the National AIDS Control Organisation (NACO) is free, private-sector management, monitoring, and treatment may incur additional costs. In this case, patients can consider getting a ₹15 to ₹20 lakh coverage with an OPD benefit.