Sexually transmitted disease (STD) or infection (STI) is a condition where bacteria, virus or parasites are transferred from one person to another.
This transmission is usually due to sexual contact or intercourse through the semen or vaginal fluids but is also often spread by blood through sharing of needles, blood transfusion etc and breastfeeding.
A lot of people wrongly assume that just because they are in perfect health condition they cannot acquire STIs.
In reality, more than 1 million healthy people get infected every day worldwide, according to the WHO.
A majority of people do not have symptoms that can be recognized and become carriers, adding to the spread.
Another major problem is that in developing countries like India, testing kits for STIs are largely unavailable or very expensive.
How to Prevent STIs
One of the most common ways to transmit STIs is unprotected sex. Therefore, it is advisable to use contraceptive barriers like condoms.
It is also important to share your sexual history with your partners to ensure no possibility of transmission.
One must possess a comprehensive sexual education to be able to recognise symptoms and get the necessary treatment.
To increase awareness so that uneducated people become aware.
Avoid sharing towels, needles and undergarments.
Vaccines are available for certain diseases like Hepatitis B and are recommended.
Lastly, it is very important to regularly get tested, despite having no symptoms as most of these diseases do not show any complications in the beginning.
Common Symptoms of STIs
There are various types of sexual diseases, and some common alarming symptoms one must look out for. They are:
Discomfort and pain during urination or sexual intercourse.
Inflammation, rashes or bumps around genitals.
Unusual vaginal or penile discharge.
Itchiness around the genitals.
Types of Sexually Transmitted Disease and Infections
Chlamydia: It is the most common STD in the world and tends to occur simultaneously with gonorrhoea. The most common type is Chlamydia trachomotuis.
The mechanism of transmission from one person to another is through sexual intercourse, childbirth and direct contact, which is a very uncommon mode of transmission for STDs.
However, Chlamydia can only live outside the body for a few seconds, so direct contact is restricted to actions like scratching the infected genital area and then touching your own eyes which usually causes conjunctivitis and eye infections.
Once the chlamydia trachomotuis bacteria gets transmitted and makes its way into the male and female genitals, it multiplies and spreads rapidly.
This bacteria is intercellular in nature and predominantly lives within the epithelial cells lining. The symptoms occur when the white blood cells recognize the bacteria inside these specific cells in the lining as a foreign invader.
Due to this, it leads to cell death and hence the urinary and genital tract gets destroyed. The pain and burning sensation felt especially during urination or sexual intercourse is associated with the destruction of epithelial lining by WBCs.
The condition is called ‘cervicitis’ when the infection spreads to the cervix, ‘dysuria’ when infected in the urinary tract and ‘urethritis’ when the infection has spread to the urethra in males.
Sometimes, the infection can also spread into the abdominal cavity and leads to pelvic inflammatory disease.
The most common symptom in males is when the destroyed epithelial cells, white blood cells and dead bacteria escape through the penis in the form of pus, especially during ejaculation and urination.
Chlamydia can also enter the bloodstream from the genitals and spread to other areas like the conjunctiva of the eyes and joints leading to dysarthiritis.
Chlamydia can be diagnosed by testing for the bacteria in swab samples, taken from the urinary or genital tract.
If a person is tested positive, treatment can be given to a patient by administering antibiotics that are best suited.
Gonorrhoea is the second most common infection and has the same mode of mechanism and targeted cells. The only difference is that it is caused by a bacteria known as Neisseria gonorrhoea.
Credits: foter Caption: Epithelial cells getting infected due to chlamydia
Syphilis – It is a sexual disease in which same sex intercourse, especially in males, are at a higher risk.
It is caused due to a bacteria called treponema pallidum.
The interesting thing about syphilis is that it cannot survive outside the human body at all. In other words, if every single person was cured from syphilis, it would be eradicated.
However, treatment of syphilis is very tricky as it takes about three weeks for a person to show symptoms after getting infected. The stage where symptoms appear, mainly at the site of contact, is known as primary syphilis.
The most evident symptom of early syphilis is the formation of lesions at the tip or around the penis or cervix, and is called chancre. The unique thing about chancre is that it is completely painless.
Another symptom is the painful enlargement of the inguinal lymph nodes.
After 9 weeks, the condition progresses to secondary syphilis. Here, the bacteria reaches the bloodstream and starts to cause symptoms that are more related to bodily functions rather than sexual.
A significant symptom is fever. The fever is caused when the white blood cells in the blood recognize the foreign invading bacteria and releases cytokines, a chemical substance that sends signals to the brain to increase the body temperature, resulting in a fever.
During the secondary phase, those “painless lesions” are transformed into painful large warts around the penis and cervix.
Lastly, the most significant symptom of secondary syphilis is the development of a skin rash called maculopapular rash that occurs all over the body. These rashes are unique as they also appear on your palms and soles.
Credit : foter Caption: Skin rash on the feet due to syphilis
The scary thing about syphilis is that 2 years after infection, the disease stops showing symptoms in the latent phase.
To add to the problem, syphilis is most contagious at this stage.
The last stage is known as the tertiary stage. Here,the infection is not contagious at all but the patient will start showing symptoms.
As the bacteria continues to fight the white blood cells, bumps appear on the surface of the infected areas like the liver, femur and skin.
It also greatly infects and causes complications in the spinal cord and cardiovascular system, and based on that, is termed as neurosyphilis and cardiosyphilis respectively.
Human Papillomavirus (HPV) – The unique thing about the HPV is that there are hundreds of strains or subtypes. So if someone were to get cured from one particular strain, it is very possible for the person to get reinfected with another strain in their lifetime.
These groups of viruses specifically infect the human epithelial cells. Since epithelial cells are found almost in all parts of the body like the hands, face, feet, respiratory tract, reproductive tract, digestive tract, lining of blood vessels etc, it is very harmful to the human body.
The interaction of the virus with these cells can cause benign and malignant tumors known as papillomas and carcinomas respectively.
Basal cells are cells in the epithelium that are responsible for replenishing and multiplying new cells in the stratified (layered) epithelium. Typically, basal cells are well protected as they are at the base of the stratified epithelium.
The only way the HPV can enter these cells is when there is a cut or injury in the epithelium. Doing so, they usually get incorporated into the basal cell’s DNA and cause unregulated growth of the epithelial cells.
This uncontrolled replication of cells is what causes warts and lesions called papillomas.
When this similar mechanism takes place in squamous epithelium cells, it forms malignant tumors or carcinomas.
Credits: foter Caption: infected squamous cells due to HPV
HPV infection is caused by coming in direct contact with infected epithelial cells. Some activities that increase the risks of contact is having an infected partner or delivering a baby through the infected canal.
A majority of the time, an HPV does not show symptoms but when it does, it will depend on the substrain. They may be:
In the cells of hand, feet and face, benign warts are formed.
Infections in the respiratory epithelial cells usually form warts or bumps which cause a change in a person’s voice and pitch.
Genital and anal Infections involve numerous warts formation. Although types are usually painless, they can cause burns, itchiness and bleeding.
Some substrain remain strictly as warts but some progress into cancers in the genital and anal areas.
Diagnosis: HPV can be tested by visual examination for warts on the skin and face. For mucosal Infections in the respiratory membrane, an endoscopy is required. This is basically the method of inserting a tube connected to a camera inside your body to detect any abnormal growth.
Treatment : Warts and lesions can be removed when treated with salicylic acid products, surgery or laser.
Sometimes, when a person is reinfected, immune modifiers can be given to help the body fight off the infection on its own.
HIV/AIDS – It is a condition in which the HIV virus causes complications in the immune system and manipulates it to target and infect the immune cells in the body until it fails. As a result, the patient will be prone to infection and fall severely ill.
When the virus enters the body it tries to gain entry into immune cells like macrophages, T helper cells and dendritic cells. The virus attaches itself to the same binding site that help immune cells communicate with the immune system.
Once this happens, the virus gains entry into the cells and replicates into a double stranded DNA by reverse transcriptase. This “Proviral” DNA is now ready to combine with the host’s DNA by entering the nucleus of the CD4 or immune cell.
Credits: foter Caption: HIV infected T cells
Ironically, this means that every time there is an infection in the body and the CD4 cells get activated, it’s nucleus starts transcribing and translating proteins that are responsible for the immune response that helps fight off the infection.
Treatment : There has been no cure found to this day.
However, medications are available to slow down the progression of the infection, transmission and reduce symptoms, enabling the patient to live a healthy and longer life.
Such drugs are known as the antiretroviral therapy (ART).
The patient is also advised to eat healthy food for proper nourishment, avoid raw meat to prevent foodborne diseases or generally try to avoid any risk of infection.
Hepatitis B: It is the most common cause of liver disease worldwide. This is a blood borne illness that spreads through sexual contact, blood transfusion or at birth from mother to child.
90% of adults who have Hepatitis B recover from the virus on their own in the first 3-6 months.
However, once Hepatitis B reaches its chronic stage, the body will not be able to fight off the virus.
The liver is an important organ of the body.
In fact, without the liver, the body wouldn’t last for more than 48 hours.
The liver stores vitamins, minerals, controls cholesterol levels and produces bile to help digests the food
When the liver gets inflamed due to the virus, all these functions are compromised.
However, during the acute phase the liver still has the ability to regenerate upto 80% but at chronic phase it could lead to increased inflammation, cirrhosis and progresses into liver cancer which will eventually cause liver fail, followed by death.
Treatment: Hepatitis B can be prevented by taking effective vaccines. Otherwise, chronic Hepatitis B cannot be cured. Like HIV, drugs can only be given to suppress it’s activity, prolong life and prevent further liver damage.
Credits: foter Caption: Vaccine for Hepatitis B