Chapter 21 - Sexually Transmitted Infections

Question 1

What are Sexually Transmitted infections? And Causes

Answer 1

STI’s are infections that are transmitted by close body contact, usually with the genital organ.

They are caused by Viruses, Bacteria, Fungi or parasites that are passed from an infected person to a partner during sexually activity.

Young people aged 15-29 years (3/4 of known cases) are the most affected by it.

Question 2

Which is infection is which - Viral, Bacterial and fungi/parasite

Answer 2

Chlamydia, Syphilis and Gonorrhoea = Bacterial infections

Herpes and HIV = viral infections

Trichomoniasis,Public Lice and Scabies = parasite

Question 3

What is Gonorrhoea? what it is and what it affects. Causes, how transmitted, who it affects.

Answer 3

Gonorrhoea (or Clap - used to be a really common disease)

Is an infectious disease that mainly affects the mucous membranes of the excretory and reproductive systems, the rectum and occasionally the eyes and throat (if oral sex occurs)

Caused by a bacterium called Neisserua gonorrhoea - commonly known as Gonococcus (pl. gonocci) because of its spherical shape.

Normally Transmitted during sexual intercourse.

Affects both males and females - appears 2-10 days after infection although may not be recognised in females

Question 4

What is the Incubation period?

Answer 4

The period between infection and the appearance of symptoms of a disease.

Question 5

How does Gonorrhoea affect males?

Answer 5

1. Bacterium enters the urethra (the duct that carries urine and sperm) during intercourse with an infected partner.
2. after incubation period inflammation in the urethra results in a BURNING FEELING in the PENIS and EXTREME PAIN when passing URINE
3. LATER A YELLOW DISCHARGE OF PUS from the penis.
4. If left UNTREATED URETHRA may become PERMANENTLY CONSTRICTED, resulting in difficulty in urinating.
5. Lack of treatment may also result in the spread of infection to other organs of the body Eg TESTES,- causing eventual sterility; JOINTS - causing a type of arthritis, of HEART OR EYES

Question 6

How does Gonorrhoea affect females

Answer 6

1. In females the disease is sometimes more serious as there no early symptoms or symptoms may go unrecognised.
   - Women often find out when sexual contacts of the infected men are traced.
   - May have the disease for months before pain causes her to seek medical advice.
2. The GONOCOCCUS ENTERS the VAGINA during intercourse with an infected male, and INFECTION OCCURS most often in the URETHRA or CERVIX.
3. There is usually NO PAIN so any PUS produced is USUALLY TAKEN to be NORMAL VAGINAL DISCHARGE.
4. UNTREATED infection SPREADS to the OVIDUCTS and to the ABDOMINAL MEMBRANES
5. OVIDUCT INFECTION may cause PERMANENT BLOCKAGE and THUS STERILITY

Question 7

What happens if a pregnant women had gonorrhoea ?

Answer 7

Discharge from the affected mucous membranes us the source if infection, and the bacteria are transmitted by contact - usually sexual.

As gonorrhoeal infection in women occurs in the cervix and the vagina.

Children born to women with the disease may be infected during birth.

The Gonococci May enter through the baby’s eyes, causing an acute eye infection that can lead to blindness.

Question 8

What is treatment for gonorrhoea?

Answer 8

Antibiotics are used in the treatment of gonorrhoea and normally result in an east and effective cure, provided treatments is begun early enough.

However strains of gonococcus that are resistant to antibiotics haven evolved and in some cases are becoming increasingly difficult to cure. (Are present in Australia)

Eg. A strain of Gonorrhoea was identified in Japan called XDR

Question 9

What is Syphilis? what it is and what it affects. Causes, how transmitted, who it affects.

Answer 9

Also known as the pox.

Syphilis is caused by a THIN, FLEXIBLE, SPIRAL-SHAPED bacterium called ‘Treponema pallidum’, whihc can only live in some mammals and humans.

This disease is normally contracted by DIRECT SEXUAL CONTACT.
* infections caused by indirect contact are extremely rare, as the bacterium can only survive for a brief amount of time outside human tissues

Syphilis affects men and women in the same way and the course of the disease follows four stages if untreated.

Question 10

What are the four stages of the course of the syphilis disease when contracted and untreated.

Answer 10

Skin is usually is a very effective barrier preventing the entry of pathogenic micro-organisms but any DAMAGE TO SKIN CAN ALLOW PATHOGENS TO ENTER.

1. The PRIMARY STAGE - syphilis bacterium enters through any small break in skin when direct sexual contact occurs.
   - incubation period ranges from 10 days to 10weeks
   - week 2-4 the BACTERIA MULTIPLY and SPREADS THROUGHOUT the BODY
   - FIRST SYMPTOM = one or small sores known as CHANCRES, usually in sex organs or sometimes in lip, finger or eyelid.
   - very SMALL (1cm or less and hidden) and HEALS in 3-8weeks without treatment and gives FALSE sense of SECURITY
2. The SECONDARY STAGE - weeks after primary stage, but may be delayed up to 12 months and CAN LAST UP TO 2 YEARS.
   - large possible symptoms: SKIN RASHES, SORE OR ULCERATED MOUTH OR THROAT, MILD FEVERS, DISORDERS OF BONE OR EYES, however can disappear without medical treatment
   - skin rash due to syphilis persists for serval weeks (any rays that fades over a few days is not due to the disease)
   - quote mild symptoms not taken seriously but PATIENT IS HIGHLY INFECTIOUS
3. The LATENT STAGE (or hidden stage) - the symptoms from the primary and secondary stages go away.
   -NO NOTICEABLE SYMPTOMS but the body is still infected
   - may last for many years and some cases the rest of the person’s life.
   INFECTION CANNOT BE PASSED ON TO OTHERS, however if symptoms of the previous stages re-emerge then making them hugely infectious again
4. TERTIARY OR LATE STAGE - even without treatment, only a minority if people infected with syphilis develop the complications associated with this stage.
   - if symptoms reappear again (5-40years later after initial infection) the results may be devastating - SYPHILITIC HEART DIEASE, INSANITY, BLINDNESS , WEAKENING OF THE BKOOD VESSEL PHYSICAL INCAPACITY and other serous inflictions.

Question 11

What is the Treatment for Syphilis?

Answer 11

ANTIBIOTICS- usual treatment for syphilis of all stages

Cure easy in primary stage - later stage: surgery is needed

Question 12

What happens if a pregnant woman is infected with syphilis?

Answer 12

The bacterium can cross the placenta and infect the developing foetus.

Infection of the woman is not necessarily followed by foetal infection, but once the bacteria enter the foetal circulation, there is nothing stopping ut from multiplying.

The foetus can go through all the stages of syphilis before birth, and may suffer from permanent damage to the heart, nervous system, joints or other organs.

Blood tests for syphilis are usually carried out during pregnancy and antibiotics can be used to treat both the mother and child

Question 13

How to control sexually transmitted infections

Answer 13

1. Abstinence - not have sex at all
2. Safe sex- taking precautions to make sure partner’s semen, vagina fluids or blood do not enter your body and that your fluids do not enter your partner’s body.
   - parts of the body may also be infectious (HERPES SORES,WARTS) should not be in contact with and must be avoided

• SAFE SEX INVOLVES THE USE OF A CONDOM; prevents the exchange of bodily fluids and prevents pregnancy
• for oral sex CONDOMS OR DENTAL DAMS can be used.
• A dental dam is a square of very thin latex which can be used as a barrier during oral sex

Question 14

There are special clinics for the treatment of STIs and free treatment is also available in public hospitals in Australia what do they do?

What is CONACT TRACING?

Answer 14

There are special clinics for the treatment of STIs and free treatment is also available in public hospitals in Australia

1. treatment is confidential and names of patients are never revealed
2. In addition to treatment the clinics also CONTACT TRACE.
   - aim is to trace by locating and treating people who have sexual contacts with the paitents
   - this way the diesel can be limited
3. education is also important for theses clinics; educate on dangers, symptoms, so they are more likely to seek treatment early when the disease can be cured easily and before passing on to others.

Question 15

What is Genital Warts? What, how,prevention, treatment, symptoms

Answer 15

Genital Warts are warts found in the genital area - vagina, labia, cervix or penis and occasionally the anus or throat.

They may look FLAT, RAISED OR CAULIFLOWER LIKE GROWTHS

Caused via Contact - then the person is infected with the by the HUMAN PAPILLOMA VIRUS (HPV) - virus has a coat made up of 72 proteins units surrounding a core of DNA

100s of strains - some are not sexually transmitted, some may cause CANCER OF THE CERVIX, however those that cause genital warts DO NOT CAUSE CERVICAL CANCER

Genital Warts are passed on via a sexual partner infected by the virus

As the warts may be inside the vagina or penis where they cannot be seen, there is a risk of being infected by a person who is unaware of tye infection

A NEW BORN BABY CAN BECOME INFECTED DURING PASSAGE THROUGH THE BIRTH CANAL.

Prevention - condom, vaccines

Treatment- prescription medications such as creams or freezing medical procedure

Question 16

What is Trichomoniasis? What, how,prevention, treatment, symptoms

Answer 16

Trichomoniasis is an infection caused by a PROTOZOAN called TRICHOMONIASIS VAGINALIS

It causes INFLAMMATION OF THE MUCOUS MEMBRANES OF THE VAGINA IN WOMEN AND URETHRA IN MEN

in WOMEN it causes a GREAT deal of DISCOMFORT; VAGINAL DISCHARGE AND SEVERE VAGINAL ITCH

in MEN - without symptoms often, but can still transmit the infection to a female

SPREAD VIA VAGINAL INTERCOURSE

PREVENTION AND TREATMENT; CONDOM AND ANTIBIOTICS

Question 17

What is Pubic Lice? (CRABS) how, when, treatment and symptoms, where

Answer 17

Pubic Lice are INSECTS called PHTHIRUS PUBIS, which are broader than they are long.

Usually confined to the PUBIC AND ANAL AREAS of the body, but in very hairy people it may be found on the CHEST AND ARM PITS.

CAUSES INTENSE ITCHING - due to allergic reaction between to the lice or their faeces.

Transmitted via sexual contact but not necessary Eg. sharing of bed
TRANSMISSION FREQUENTLY OCCURS MERELY THROUGH PROLONGED, WARM, CLOSE CONTACT.

TREATMENT - lotions are applied to the skin; lotions kill the insects and their eggs.

Question 18

What is SCABIES? (The itch) how, when, treatment and symptoms , where

Answer 18

Scabies is caused by a mite called SARCOPTES SABEI.
- members of the arachnida (spiders, scorpions - all 8 legs)

Appears to prefer the GENITAL REGION , WRITS, FINGER WEBS
- infected areas are very itchy especially AT NIGHT - often making sleeping impossible

ITCHING may be DUE TO SENSITIVITY TO THE MITE OR ITS FAECES.

Transmitted via sexual contact but not necessary Eg. sharing of bed
TRANSMISSION FREQUENTLY OCCURS MERELY THROUGH PROLONGED, WARM, CLOSE CONTACT.

TREATMENT - lotions are applied to the skin; lotions kill the insects and their eggs.

Question 19

What causes Chlamydia?

Answer 19

Chlamydia is caused by a MICRO-ORGANISM called ‘CHLAMYDIA TRACHOMATIS’

The cause of the disease was difficult to identify because it acted like a virus in many ways, but it is actually a HIGHLY SPECIALISED AND ADAPTED BACTERIUM

• this bacterium can only reproduce while inside a living human cell
• it was impossible to grow the bacterium on normal nutrient media because such media does not contain living cells.

Question 20

Explain Chlamydia. Symptoms, who, how, treatment

Answer 20

Chlamydia trachomatis is transmitted by VAGINAL or ANAL SEX with an infected person.

Both MEN AND WOMEN CAN BE AFFECTED and occurs frequent in people aged under 25.

Most people show NO SYMPTOMS and are unaware that they are infected and therefore sometimes called the ‘silent infection’

when the infection is identified it can be treated by ANTIBIOTICS

Question 21

How are MEN affected with Chlamydia?

Answer 21

May develop INFECTION in the URETHRA known as NON-SPECIFIC URETHRITIS (NSU)

• this is INFLAMMATION of the URETHRA, and does not indicate the cause of the inflammation
• CAUSES A BURNING SENSATION WHIKE URINE PASSES

Frequently PUS IS PRODUCED but when examined it shows no evidence of disease- causing organisms.
- YELLOW, MUCUS-LIKE DISCHARGE from the PENIS

If infection is not treated
- Bacterium can SPREAD TO EPIDIDYMIS where it causes inflammation called EPIDIDYMITIS
- causes PAIN AND SWELLING
— can lead to INFERTILITY if both testes are affected, how both testes having it is rare

IN AUS CHLAMYDIA IS THE MOST COMMON CAUSE OF EPIDIDYMITIS IN MEN UNDER THE AGE OF 35.

Question 22

What micro-organisms can cause NSU IN MEN?

Answer 22

• CHLAMYDIA TRACHOMATIS (bacterium - chlamydia)
• ESCHERICHIA COLI (a bacterium)
• CANDIDA ALBICANS (a fungus)
• HERPES SIMPLEX (a virus)

Question 23

How are WOMEN affected with Chlamydia?

Answer 23

Most women have no symptoms - no idea they have chlamydia
- this makes the diease very dangerous because if untreated it CAN CAUSE INFERTILITY, EYE INFECTION AND ARTHRITIS

Some women may show SYMPTOMS OF PELVIC INFLAMMATORY DISEASE (PID)
- INFLAMMATION OF THE ORGANS IN THE PELVC REGION SUCH AD THE UTERINE TUBES AND UTERUS.

• continual inflammation of the uterine tubes may lead to BLOCKAGE BY SCAR TISSUE - thus infertility
• IMPLANTATION OF AN EMBRYO OUTSIDE TYE UTERUS - ECTOPIC PREGNANCY - may also occur.

Question 24

What happens to a Baby if the mother has Chlamydia?

Answer 24

70% chance that the disease will be passed to foetus during birth

Baby may suffer from CONJUNCTIVITIS (inflammation of the mucous membrane covering the eyeball), NOSE AND THROAT INFECTIONS OR PNEUMONIA

There is some evidence that chlamydia may cause a significant increase in the RISK of HAVING a PREMATURE BABY.

Question 25

Treatment of Chlamydia.

Answer 25

Correct diagnosis and treatment is vital.

If suspected of the disease a URINE TEST can be done for both males and females.

Most ACCURATE DIAGNOSIS can be made with a SWAB of the VAGINA, CERVIX, ANUS OR PENIS, which is then analysed in a lab.

If confirmed - TREATMENT IS A COURSE OF ANTIBIOTICS, although even with the prolonged treatment the bacterium may never be completely eliminated from the body.

Question 26

Vaccine of Chlamydia?

Answer 26

Vaccine trails are occurring but not one for a few decades

Researchers have developed a vaccine which prevents infertility from chlamydia in mice.

Innovative approach that does not aim to vaccinate against contracting the disease, but builds the body’s tolerance to the bacterium
- does have negatives right now such as infertility

Question 27

Explain Trachoma

Answer 27

The same bacterium that causes sexually transmitted chlamydia infection also CAUSES the EYE DISEASE TRACHOMA.

TRACHOMA IS AN ENDEMIC IN 51 countries and is the MAIN CAUSE of INFECTIOUS BLINDNESS.

Has been largely eliminated from developed countries due to improved standards of hygiene and sanitation but still persists in developing countries.

Question 28

What is Non-Specific genital infection?

Answer 28

NSG - Non-specific urethritis (NSU) means any inflammation of a man’s urethra (the tube that carries urine from the bladder to the outside) that is not caused by gonorrhoea (a sexually transmissible infection).

Approximately 90% of cases appear to be chlamydia

Question 29

What is Genital Herpes?

Answer 29

Genital Herpes is a common STI caused by the HERPES SIMPLEX VIRUS

There are 2 forms of the virus
- both types of the virus are transmitted by skin-to-skin contact and therefore be passed on during genital, oral, or anal sex.

**1. Herpes Simplex Type 1 (HSV1) - usually produces ‘COLD SORES’ on the lips but can also affect the genitals.

**2. Herpes Simples Type 2 (HSV2) - produces BLISTERS ON THE GENITAL ORGANS

Question 30

Explain what genital herpes does to the body once it’s infected? (+ SYMPTOMS)

Answer 30

1. The FIRST EPISODE is usually the most SEVERE and can be VERY PAINFUL AND DISTRESSING
   - BLISTERS DEVELOP IN AREAS SUCH AS THE PENIS OF MALES, AND THE LABIA AND VAGINA OF FEMALES
2. It may be accompanied by FLU-LIKE SYMPTOMS OR A RASH
3. The BLISTERS BREAK, forming ULCERS that then develop SCABS.
4. HEALING OCCURS over a period of 1-2 weeks
5. Although healing has occurred SOME OF THE VIRUS PASSES INTO NERVOUS SYSTEM WHERE IT REMAINS FOR LIFE
6. The VIRUS CAN REINFECT the SKIN or MUCOUS MEMBRANES of the GENITAL ORGANS at ANY TIME, BLISTERING CAN REOCCUR
7. Recurrent episodes are not normally as painful and are a SHORTER DURATION THAN THE FIRST ATTACK
8. VIRUS CAN STILL BE TRANSMITTED TO OTHERS EVEN WHEN THERE IS NO SYMPTOMS

Question 31

What happens to children born to mothers with herpes?

Answer 31

The HERPES SIMPLEX VIRUS CAN BE TRANSMITTED from an INFECTED MOTHER TO A BABY DURING BIRTH.

IN children born to infected mothers SERIOUS MALFORMATIONS AND LIFE THREATENING DISEASES MAY OCCUR. - although not as common

Question 32

What is the Treatment of Herpes?

Answer 32

There is NO WAY OF TREATMENT against herpes virus once infected

The TREATMENT INCLUDES

• MEDICATION to REDUCE PAIN,
• SALINE DRESSINGS TO CLEAN UP THE BLISTERS,
• SEXUAL ABSTINENCE for the DURATION OF ERUPTION

ANTIVIRAL DRUGS SPECIFIC to HERPES can be PRESCRIBED but DOES not CURE DIEASE - only ACTS TO REDUCE SEVERITY AND LENGTH OF AN ATTACK.

Question 33

Explain what Human immunodeficiency virus is.

• What and a summary of what it does
• Relates to aids?
• how long?

Answer 33

HIV is a Retrovirus contains an RNA core rather than a core of DNA .

It is similar to other virus in that it is UNABLE TO REPRODUCE BY ITSELF.

It weakens the body’s immune system and so the infected person is susceptible to infection by other micro-organisms and to some forms of cancer.

Almost all cases of HIV infection eventually result in ACQUIRED IMMUNE DEFICIENCY SYNDROME OR AIDS.

Anyone infected with HIV REMAINS INFECTED FOR LIFE

• however time taken for infection to develop into AIDS VARIES
• months - 20 years

Question 34

Explain the procedure on how the HIV virus affects the body

Answer 34

1. HIV INFECTs WHITE BLOOD CELLS known as T-LYMPHOCYTES.
2. INSIDE the HOST CELL the VIRUSES USES ENZYMES CALLED REVERSE TRANSCRIPTASE , to CONVERT ITS RNA into DNA
3. The DNA then PRODUCES MILLIONS of COPIES of itself, which are RELEASED into the BLOOD to INFECT MORE T-LYMPHOCYTES
4. approximately a MONTH LATER, (after initial infection) an infected person may suffer FLU -LIKE SYMPTOMS
5. IMMUNE RESPONSE deals with the infection at this stage and the PATIENT RECOVERS
6. LONG PEROID where the person is SEEMINGLY FIT
7. During this period the VIRUS CONTINUES TO DESTROY T-CELLS UNTIL NUMBER OF THESE CELLS BECOME SO LOW.
8. IMMUNE SYSTEM IS NO LONGER ABLE TO RESIST BACTERIAL, VIRAL OR FUNGAL INFECTIONS AND CANCERS ARE LIKLEY TO DEVELOP.
9. Persons has aids

Question 35

What is Aids?

Answer 35

Acquired Immune Defiecenty

• ACQUIRED means that the condition is NOT INHERITED
• SYNDROME refers to a SET of SYMPTOMS/ILLNESSES that OCCUR as a RESULT of ONE CAUSE

IN THE CASE OF AIDS THE CAUSE IS INFECTION BY HIV

Question 36

How is HIV spread? And through which fluids?

Answer 36

Body fluids in which the virus is present must be passed directly into a person’s bloodstream or come into contact with mucous membranes.

The bodily fluids that are ABLE TO CARRY ENOUGH HIV TO BE INFECTIONS are BLOOD (including menstural blood), SEMINAL FLUID (including pre-ejaculatory fluid,) CERVICAL AND VAGINAL FLIUDS, BREAST MILK.

Question 37

How can HIV not be transmitted?

Answer 37

The virus does not survive for long outside the human body, and is NOT TRANSMISSIBLE THROUGH AIR AND WATER.

UNLESS BLOOD IS PRESENT, the virus is not found sufficient quantities to be infectious in URINE, FAECES, VOMIT, TEARS, SWEAT OR SALIVA

Normal social contacts such as

• hugging
• kissing
• handshaking
• coughing
• sneezing
• sharing cutlery or crockery

Question 38

List some ways in which HIV may be spread (5)

Answer 38

• UNPROTECTED SEXUAL INTERCOURSE (vaginal and possibly oral) with infected person
• SHARING NEEDLES/SYRINGES with infected person
• INFECTED MOTHER - to CHILD during PREGNANCY, CHILDBIRTH, BREASTFEEDING
• BLOOD TRANSFUSIONS in countries where BLOOD IS NOT TESTED CAREFULLY
• IMPLEMENTS THAT PEIRCE THE SKIN which HAVE NOT BEEN STERILISED.
  EG. body and ear piercing equipment, tattooing, medical and dental procedures

Question 39

To reduce the risk of becoming infected with HIV, there are a number of preventative measures that should be taken, which are: (5)

Answer 39

• CHOOSE NOT TO HAVE SEXUAL INTERCOURSE
• NOT inject drugs
• PROTECTED SEX OR WITH A PARTNER WHO WILL NOT HAVE EEX WITH ANYONE ELSE
• *HIV testing should be done to ensure both are not infected
• CONDOM USED; if multiple partners
• NEEDLES, SYRINGES and ITEMS TO have HUMAN BLOOD should NEVER BE SHARED
• OPEN CUTS/SORES on SKIN should be WASHED and COVERED and NOT allowed to come in CONTACT with HUMAN BLOOD.

Question 40

Stages of Diagnosis for HIV

Answer 40

1. If infected TREATMENT CALLED ‘POST EXPOSURE PROPHYLAXIS’ (PEP) can be Given
   - TREATMENT CONSISTS of a COURSE OF DRUGS TAKEN FOR ONE MONTH
   - Started within 3-days Of Possible exposure.

• the drugs PREVENT THE REPLICATION OF THE VIRUS so that it’s DOES NOT BECOME ESTABLISHED IN THE BODY
• not 100% effective

2. BODY RESPONDS TO HIV INFECTION by PRODUCING chemical substances called ANTIBODIES
   - HIV IS DIAGNOSED BY TESTS THAT DETECT THE PRESENCE OF AN HIV ANTIBODY IN THE BLOOD
   - depending on the body - usually takes up 2-12 weeks for the antibodies to build up to the point to be detected.
3. If this test is NEGATIVE, then 10-12 weeks later a SECOND TEST is recommend to make sure no antibodies have developed.

Question 41

What are other test for HIV is available in Australia? What is Viral Load?

Answer 41

Tests that measure viral Load

Viral load is the TERM USED to DESCRIBE the AMOUNT of HIV IN the BLOOD that GIVES an INDICATION of the ACTIVITY OF the VIRUS.

The ACTIVITY of the virus can be DETERMINED from the RATE at which the VIRUS REPLICATES and gives a GUIDE TO the LIKELIHOOD OF DAMAGE TO the IMMUNE SYSTEM.

The RESULTS of viral load tests are given in terms of the number of the viral COPIES of HIV per MILLIMETER OF BLOOD.

Question 42

What is the TREATMENT USED FOR HIV?

Answer 42

No vaccines for prevention. Currently number of ANTIVIRAL DRUGS DIVIDED INTO CLASSES DEPENDING ON WHICH STAGE OF THE TGE VIRAL LIFE CYCKE THEY AFFECT.

1. Patients are usually given a COMBINATION OF MANY DRUG CLASSES - ‘cocktail of drugs’
   - CONTENTS of drug DEPENDS on how HIGH THE VIRAL LOAD IS
   - AND WHETHER they HAVE had PREVIOUS TREATMENT ( which the virus has developed resistance against)

Combination therapies have shown the SLOWING OF REPLICATION OF HIV and SUPPRESSING PROGRESSION in some people

Some cases THEY REDUCE the viral load to levels that CANNOT BE DETECTED

• however VIRUS STILL REMAINS IN TISSUES such as the SPLEEN AND LYMPH NODES
• Therefore THERAPY MUST BE CONTINUED INDEFINITELY

Question 43

One problem with trailing a vaccine for HIV developed by researchers is

Answer 43

Researchers must URGE ALL VOLUNTEERS TO CONTINUE TO EMPLOY SAFE SEX PRACTICES

• therefore the EFFECTIVENESS of the vaccine will become AVAILABLE only if ENOUGH PEOPLE in the trial IGNORE THIS ADVICE AMD EXPOSE THEMSELVES TO THE VIRUS
• this means it may take many years before the reliability of the vaccine is established