STIs Flashcards
STI definition
infections passed on from one person to another by intimate or sexual contact.
- STIs = single most important cause of reproductive disorders
common STIs
Bacterial (Chlamydia, Syphilis)
Viral (Herpes, Papilloma virus, HIV, HCV, HBV
Fungal and other
STI vs BBV
BBV = blood borne virus
- STIs: Chlamydia, Gonorrhoea, Syphilis, Donovanosis, Chancroid
- BBVs: HIV, Hepatitis B (HBV), Hepatitis C (HCV)
modes of transmission
- Sexual transmission
- Body fluids
- Skin-to-skin contact
- Blood
- Saliva
- Sharing of needles and needle stick injuries
- Vertical transmission (from a pregnant woman to fetus/infants)
signs of infection
Depending on the pathogen:
- Pain
- Fever and malaise
- Discharge
- Swelling
- Burning
- Itching
- Redness
- Ulcers
vaginal discharge
Vaginal discharge is most often a normal and regular occurrence –> cleans and protects vagina
- Certain types of discharge can indicate an infection e.g. abnormal discharge may be yellow or green, chunky in consistency, or foul smelling
- Yeast or a bacterial infection usually causes abnormal discharge
- abnormal discharge caused by: Herpes simplex virus (HSV) T1 or T2, bacterial vaginosis, chlamydia trachomatis infection, Neisseria gonorrhoeae
penile discharge
- May be watery/clear or cloudy (containing pus) or bloody
- Common causes: Urinary tract infection (UTI) or STIs
- Often accompanied by itching, pain or burning during urination and frequent urination
- caused by: Chalymida trachomatis infection, Neisseria gonorrhoeae, Trichomonas
chlamydia
- Most common bacterial STI
- Bacterial infection caused by Chlamydia trachomatis
- Symptoms may be minimal, e.g. drainage from vagina or penis, lower abdominal pain, dyspnoea, 80% of women have no symptoms
- Responsible for 25–50% of all diagnosed cases of pelvic inflammatory disease –> if left untreated, can lead to sterility
- Newborns infection after vaginal birth can develop: Trachoma = painful eye infection that can lead to corneal scarring, respiratory tract inflammations e.g. pneumonia
- Treatment: antibiotics
gonorrhoea
- Symptoms: discharge of pus, dysuria, urethritis, females often asymptomatic
- Bacterial infection of mucus membranes caused by Neisseria gonorrhoeae = “the clap”
- Spread by contact with infected mucosae of genital, anal, pharyngeal or urinary system
- Treatment: antibiotics, but resistant strains are becoming prevalent
Syphilis - infectious agent
- Caused by Treponema pallidum (spirochaete bacterium)
- Bacteria invades mucosae or broken skin
- Can cause miscarriage, produce congenital deafness and mental retardation
syphilis symptoms
1º: Infection is asymptomatic for 2–3 weeks and then painless syphilitic sore, known as a chancre appears at site of infection
- Disappears within a few weeks
2º : If untreated several weeks later
- Pink skin rash, fever, and joint pain can develop
- Appear for 3–12 weeks, then disappear
3º: Disease can enter latent period (for 6-12mo); Tertiary syphilis is characterized by gummas = lesions that develop in CNS, blood vessels, bones, and skin, can damage eyes, ears, bone, heart, brain
o Early treatment with penicillin prevents harm
HIV - infectious agent
- HIV=retrovirus that infects T cells -> get destroyed
- If too many T cells destroyed =AIDS (opportunistic infections)
- HIV-1 and HIV-2
- Infection during vaginal birth, or while breast-feeding (“biting”)
- > caesarian reduces infection significantly
- Antiviral drugs administered to mother e.g. ZDV reduces transmission
- HIV can be transmitted from one person to another by the exchange of certain body fluids. Body fluids that can contain enough HIV to be infectious are: blood (including menstrual blood,) vaginal fluids, breast milk and semen (pre-ejaculatory fluid)
(human immunodeficiency virus, acquired immunodeficiency syndrome)
HBV
hepatitis B virus
- Most common liver infection in the world
- Hepatitis B infection can lead to cirrhosis (scarring of the liver), liver cancer, or liver failure, if it is not diagnosed and managed appropriately.
- Transmission through blood and sexual contact
- If hepatitis B virus test positive > 6 months after infection= ’chronic‘ hepatitis B (can last a lifetime) -
- Vaccine available
HCV
hepatitis C virus
- Chronic infection with ongoing liver inflammation can lead to liver cirrhosis (scarring of liver) or liver cancer
- Most people in Australia have hep C genotypes 1 and 3 (6 main genotypes)
- New hep C treatments are safe and very effective ->up to 95% of people can now be cured
- Rarely transmitted as an STI
- No vaccine available
(75% have lifelong infection, 25% infected - virus is cleared by immune system)
non-notifiable diseases
genital herpes
HPV - human papillomavirus
