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Unformatted text preview: SODeL JKUAT JOMO KENYATTA UNIVERSITY OF AGRICULTURE & TECHNOLOGY SCHOOL OF OPEN, DISTANCE AND eLEARNING P.O. Box 62000, 00200 Nairobi, Kenya E-mail: [email protected] SZL 2111: HIV/AIDs JJ II J I J DocDoc I Back Close LAST REVISION ON March 27, 2013 SZL2111 HIV/AIDs This presentation is intended to covered within one week. The notes, examples and exercises should be supple- mented with a good textbook. Most of the exercises have solutions/answers appearing elsewhere and accessible by SODeL JKUAT clicking the green Exercise tag. To move back to the same page click the same tag appearing at the end of the solution/answer. Errors and omissions in these notes are entirely the responsibility of the author who should only be contacted JJ II J I J DocDoc I Back Close through the (SODeL) Department of Curricula & Delivery and suggested corrections may be e-mailed to [email protected] 2 SODeL JKUAT SZL2111 HIV/AIDs JJ II J I J DocDoc I Back Close 3 SZL2111 HIV/AIDs SZL 2111: HIV/AIDs Course Description General introduction: Public health and hygiene, human reproductive system, sex and sexuality. History of sexually transmit- SODeL JKUAT ted diseases (STDs); History of Human Immunodeciency virus/ Acquired Immune deciency Syndrome (HIV/AIDS), Comparative information on trends, global and local distribution, Justication of importance of course. Biology of HIV/AIDS; Overview of immune system, natural immunity to HIV/AIDS. The AIDS virus and its life cycle, disease progression, transmission and diagnosis. JJ II J I J DocDoc I Back Close Discordant couples. Treatment and Management; nutrition, prevention and control; Abstain, Be faithful, Condom use, Destigmatize HIV/AIDS (ABCD) methods and antiretro4 SZL2111 HIV/AIDs viral drugs and vaccines. Pregnancy and AIDS. Management of HIV/ AIDS patients. Social and cultural practices: Religion and AIDS. Social stigma on HIV/AIDS. Behavioral change. Voluntary Counseling and Testing Services. Gender and HIV/AIDS. SODeL JKUAT Drug and alcohol abuse and HIV/AIDS. Poverty and AIDS. Families and AIDS orphans. Government policies: Global policies of AIDS. Legal rights of AIDS patients. AIDS Impact: Family /society setup, population, agriculture, education, health, industry, development, economy and other sectors. Prerequisite: JJ II J I J DocDoc I Back Close none Course aims 1. To bring about behavioral change 5 SZL2111 HIV/AIDs 2. To prevent HIV/AIDS and reduce the threat it poses to youth/students 3. To promote HIV/AIDS education as a means of producing better and more integrated sense of health education in the SODeL JKUAT student Learning outcomes Upon completion of this course you should be able to know; 1. Biology of HIV 2. Transmission of HIV 3. Disease progression and symptoms JJ II J I J DocDoc I Back Close 4. Treatment of HIV/AIDs Various strategies of managing of HIV/AIDs 6 SZL2111 HIV/AIDs 5. How to prevent and control of HIV/AIDs 6. Social and cultural practices that contribute to spread of HIV/AIDs 7. Policies and rights of people living with HIV/AIDs SODeL JKUAT 8. Implications of HIV/AIDs on various sectors Instruction methodology ˆ Lectures: oral presentation generally incorporating additional activities e.g writing on chalk board, exercises, class questions and discussions or student presentation. JJ II J I J DocDoc I Back Close ˆ Tutorials to give the students more attention. ˆ Assignments and Demonstrations. 7 SZL2111 HIV/AIDs Assessment information The module will be assessed as follows; ˆ 10% of marks from two (2) assignments to be submitted online SODeL JKUAT ˆ 20% of marks from two written CAT to be administered at JKUAT main campus or one of the approved centres ˆ 70% of marks from written Examination to be administered at JKUAT main campus or one of the approved centres JJ II J I J DocDoc I Back Close 8 SODeL JKUAT Contents 1 TRANSMISSION AND DIAGNOSIS OF HIV 1.1 Diagnosis of HIV and AIDs 1.1.1 J DocDoc I Back Close 13 The Enzyme-Linked Immunosorbent Assay (ELISA) JJ II J I . . . . . . . . . . . . 12 . . . . . . . . . . . . . . . . 1.1.2 The Western blot assay 1.1.3 PCR 13 . . . . . . . . . . 14 . . . . . . . . . . . . . . . . . . . . 15 9 SZL2111 HIV/AIDs SODeL JKUAT 1.2 JJ II J I J DocDoc I Back Close 1.1.4 CD4+Cell count 1.1.5 Measuring viral load Transmission of HIV 17 . . . . . . . . . . . . . . . . 18 Modes of HIV Transmission 1.2.2 Factors that increase chances of MTCT/ 1.2.3 15 . . . . . . . . . . . . 1.2.1 Determinants 1.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Prevention of MTCT (PMTCT) STIs, STDs, FGM and HIV/AIDS 19 24 . . . . . 25 . . . . . . . . 28 1.3.1 Common examples of STIs/ STDs 1.3.2 Relationship between HIV & STDs/STIs 29 1.3.3 Dangers/ risks of STDs/STIs 30 1.3.4 Why teenagers don't seek treatment 1.3.5 FGM (Female Genital Mutilation) ˆ Types of FGM 10 . . . . . . . . . . . 28 . . . 31 . . . . 32 . . . . . . . . . . 33 SZL2111 HIV/AIDs ˆ Eects of FGM leads to condi. 34 Solutions to Exercises . . . . . . . . . . . . . . . . 40 SODeL JKUAT tions that favours HIV survival JJ II J I J DocDoc I Back Close 11 SZL2111 HIV/AIDs LESSON 1 TRANSMISSION AND DIAGNOSIS OF HIV SODeL JKUAT Learning outcomes Upon completing this topic, you should be able to understand: ˆ Various methods used in diagnosis of HIV ˆ The modes of HIV transmission ˆ Pregnancy and HIV/AIDS JJ II J I J DocDoc I Back Close 12 SZL2111 HIV/AIDs 1.1. Diagnosis of HIV and AIDs A number of tests are used to conrm the presence of antibody to HIV and to assist in diagnosing HIV infection. SODeL JKUAT 1.1.1. The Enzyme-Linked Immunosorbent Assay (ELISA) ˆ The test identies antibodies directed specically against HIV. The ELISA test does not establish a diagnosis of AIDS. Rather, it indicates that the person has been exposed to or infected with HIV. People whose blood contains antibodies for HIV are said to be seropositive. HIV antibodies do not reach detectable levels in the blood for one to three months. This period is known as sero conver- JJ II J I J DocDoc I Back Close sion during which antibody production to viral proteins take place.  Window period is the time during which an13 SZL2111 HIV/AIDs tibody detection using Elisa is negative. In some cases it may take even 6 months for the antibody levels to get high enough for detection. SODeL JKUAT 1.1.2. The Western blot assay ˆ It is another test that can identify HIV antigens and is used to conrm seropositivity as identied by the ELISA. This is a method that detects very low antigen levels such that one may test HIV negative by ELISA but test positive through western blot. Babies born of HIV mother have antibodies to HIV that were passed on during pregnancy through the placenta. However these antibodies di- JJ II J I J DocDoc I Back Close minish with time such that by 15 months the child may test negative. Use of Western, blot conrms presence of 14 SZL2111 HIV/AIDs HIV antigen and this rules out whether babies are positive because of HIV itself or because of maternal antibodies. 1.1.3. PCR SODeL JKUAT ˆ It is also used to detect HIV in high-risk seronegative people before the development of antibodies, to conrm a positive ELISA, to screen neonates, and to determine the exact strain of virus that is present. 1.1.4. CD4+Cell count ˆ Once a patient is diagnosed positive the extent of damage to the immune system is determined by CD4+ cell count JJ II J I J DocDoc I Back Close (T-helper cell count). The number of CD4 cells present is a direct indicator of the immune system's ability to ght 15 SZL2111 HIV/AIDs o opportunistic infections. The test to measure CD4 cells requires a sample of blood to be taken and measurement is made of the number of CD4 cells in a cubic milliliter of blood and will give a picture of the health of the immune SODeL JKUAT system-whether it is improving or declining. The CD4 count of a person who is not infected with HIV may lie anywhere between 500 and 1200.A drop in an HIV positive persons CD4 count usually occurs over a number of years. A CD4 count between 500 and 200 indicate that some damage to the immune system has occurred and a count below 350 or rapid decline is an indication that one should consider anti-HIV treatment. JJ II J I J DocDoc I Back Close 16 SZL2111 HIV/AIDs 1.1.5. Measuring viral load Measuring viral load is essential to determine how active the viral replication is if one is taking anti-HIV medication, then it is also a direct indicator of how successful it is in suppressing SODeL JKUAT viral replication. The viral load test requires the collection of a blood sample and estimates the number of HIV particles in the sample by looking for HIV genes. The level of viral load is generally seen as a good indicator of whether to start antHIV treatment. An undetectable viral load is an indication that both the risk of developing AIDS and the risk of developing drug resistance has been reduced. A high viral load is an indication of high levels of HIV in body uids while undetectable viral load JJ II J I J DocDoc I Back Close indicates a reduction in levels of HIV in these uids but the risk of transmitting the virus is still present 17 SZL2111 HIV/AIDs 1.2. Transmission of HIV ˆ HIV is present in semen, vaginal/ cervical secretions & body uids. It may be present in tears, urine, csf, breast milk &infected discharges, saliva. HIV is spread when an SODeL JKUAT infected individual come into contact with infected body uids or cells. How HIV is NOT transmitted. ˆ There is no evidence to show that HIV can be transmitted by:    casual social contact e.g. shaking hands, hugging sneezing or coughing shared facilities & equipment e.g. toilets, swimming pools JJ II J I J DocDoc I Back Close   non wet kissing sharing food & utensils 18 SZL2111 HIV/AIDs  insect bites e.g. mosquitoes - HIV only lives for a short time and does not reproduce in an insect   Injecting with sterile needles Protected sex - If an unbroken latex condom is used, SODeL JKUAT there is no risk of HIV transmission. There are myths saying that 'some very small viruses can pass through latex' - this is not true. 1.2.1. Modes of HIV Transmission 1. Sexual contact - Any unprotected (no condom) penetrative sex whether vaginal, anal or oral can transmit HIV from infected individual to uninfected sexual partner. JJ II J I J DocDoc I Back Close (a) Heterosexual contact (man &woman) a/c 70%-80% of all HIV transmission. 19 SZL2111 HIV/AIDs (b) Homosexual contact a/c 5-10% (c) Oral sex is low risk but oral ulcers, bleeding gums, genital sores & presence of STIs (gonorrhea, syphilis & genital ulcers) do increase the risk of hiv transmis- SODeL JKUAT sion (d) Rape, & sodomy victims could get infected if the attacker is HIV+. The victims should seek prompt medical attn because early treatment with ARVs can greatly reduce chances of HIV infection. They will also require specialized counseling & psychological /psychiatric care Factors that inuence transmission through sexual contact JJ II J I J DocDoc I Back Close (e) The risk of HIV transmission through sexual contact is inuenced by a number of factors: 20 SZL2111 HIV/AIDs i. level of virus in the body ii. number of sexual partners iii. sex  male/female iv. age SODeL JKUAT v. STDs/STIs vi. Condom use 2. Intravenous Drug Use/ Contaminated Piercing Instruments - I.V. drug use is the administration of drugs of addiction e.g heroin into the blood stream by injecting into the veins. Most drug users tend to shoot in groups & often share needles. It therefore becomes very easy for transmission /infection to occur from one infected group JJ II J I J DocDoc I Back Close member to another. It's a signicant modes in the de- veloped countries accounting for 5-10% of HIV infections. 21 SZL2111 HIV/AIDs Procedures such as ear piercing & circumcisions when done with poorly cleaned & unsterile instruments can lead to HIV transmission. 3. Occupational exposure/ Infection in the healthcare setting - Occupational exposure is the accidental JKUAT exposure of healthcare workers (e.g doctors &nurses) to SODeL body uids from an infected patient in their care. This is most frequently due to needle pricks or cuts with surgical instruments. Infection can also occur due to contact with infected blood, laboratory samples especially through broken skin. 4. JJ II J I J DocDoc I Back Close Mother - to - child transmission (MTCT) - Also called Vertical / perinatal transmission & it accounts for 13-40% HIV infections. It's possible for HIV to be trans22 SZL2111 HIV/AIDs mitted from HIV+ mothers to unborn child. This occurs in 3 ways: (a) During pregnancy- The virus crosses from mother's blood to child through the placenta. Although there's SODeL JKUAT no exchange of blood between mother & child, researchers believe that the foetus can get HIV through the placenta i.e through diusion. It accounts for about 35% HIV infections (b) During birth  Through exposure to mother's blood & other secretions. It accounts for 65% HIV infec- tions (c) After birth- through breast feeding. Breast milk con- JJ II J I J DocDoc I Back Close tains minimal quantities of HIV. It accounts for 15% HIV infections. 23 SZL2111 HIV/AIDs 1.2.2. Factors that increase chances of MTCT/ Determinants ˆ high level of HIV in mother's blood & other body uids SODeL JKUAT (maternal viral load) ˆ duration of exposure to maternal secretions during delivery ˆ inadequate nutrition ˆ pre-term delivery- premature babies are more prone to infection because the immune mechanism is still very weak/ immature JJ II J I J DocDoc I Back Close ˆ Maternal immune response- maternal CD4 cell count ˆ prolonged membrane rupture-increased risk if more than 4hours ˆ obstetrical procedures- e.g. vacuum assisted delivery 24 SZL2111 HIV/AIDs ˆ unprotected sexual intercourse ˆ presence & amount of virus in the genital tract ˆ Placenta barrier- breaches in barrier leads to mixing of maternal and foetal cells SODeL JKUAT ˆ Presence and amount of HIV in genital tracts 1.2.3. Prevention of MTCT (PMTCT) ˆ Prevent HIV infection in women i.e. encouraging teenage girls to delay sexual relationships & discordant couples to use of condoms. ˆ JJ II J I J DocDoc I Back Close Reduce the number of HIV exposed pregnancies i.e. Women who are HIV infected can use family planning methods to prevent pregnancies. 25 SZL2111 HIV/AIDs ˆ ART- to infected pregnant women.e.g. AZT (zidovudine/ azidothymidine- Nov '94) is taken in the last week of pregnancy and nevirapine is given at the onset of labour & to the HIV exposed babies within 3 days after birth SODeL JKUAT ˆ Preventing malaria - A woman who is infected with both HIV and malaria has an increased chance of passing HIV to her baby. Anti-malarial drug treatment during pregnancy is therefore an important part of preventing MTCT ˆ Reducing trauma and shortening exposure of the baby to the virus during labour and delivery i.e. Modied obstetrical practices which include JJ II J I J DocDoc I Back Close  make sure that the mother gives birth within 4 hours after membrane ruptures (water breaks),  avoid routine episiotomy, 26 SZL2111 HIV/AIDs    ˆ avoid prolonged labour, minimum use of vacuum or forceps delivery, and Electing to use caesarian section. Appropriate choice of feeding infants i.e. breastfeeding ex- SODeL JKUAT clusively without any supplements followed by abrupt but timely weaning or replacement feeding from birth without any breast milk. JJ II J I J DocDoc I Back Close 27 SZL2111 HIV/AIDs 1.3. STIs, STDs, FGM and HIV/AIDS STDs are diseases that are transmittable from an infected person to another through sexual intercourse. STIs is a term applied to infections that are transmitted primarily through sexual contact SODeL JKUAT be it vaginal, oral, or anal intercourse. They don't necessarily involve sexual activity but the organisms that cause STIs enters mostly through the soft & thin skin that cover the inner surfaces i.e. mucus membrane of the vagina, urethra, anus & mouth. However, in some instances exposure to sores or other types of skin to skin contact may be insucient to transmit the infection. 1.3.1. Common examples of STIs/ STDs JJ II J I J DocDoc I Back Close ˆ Syphilis ˆ Gonorrhea 28 SODeL JKUAT SZL2111 HIV/AIDs ˆ Candidacies ˆ Hepatitis B & C. ˆ Chancroids ( genital sores) ˆ Genital herpes (Herpes Simplex V) ˆ Genital warts( Human Papilloma V) ˆ Bacterial vaginosis. ˆ Trichomoniasis 1.3.2. Relationship between HIV & STDs/STIs STIs/STDs increase the risk of HIV infection by mobilizing a high population of T cells to ght the STI/STD. Since the T cells JJ II J I J DocDoc I Back Close are the target cells for attack by HIV, such a large population will inevitably provide breeding ground for HIV. STDs/STIs also 29 SZL2111 HIV/AIDs increase the risk of acquiring or transmitting the virus. Both are transmitted through sexual contact & to unborn baby during pregnancy or at birth. SODeL JKUAT 1.3.3. Dangers/ risks of STDs/STIs JJ II J I J DocDoc I Back Close ˆ Increased risks of getting infected with HIV or the risk of infecting others ˆ High incidences of infertility e.g. pelvic inammatory disease if untreated result in infertility or tubal pregnancies. ˆ Future problems with pregnancies & child birth ˆ Mental disorders & deaths especially in syphilis Treatment of STDs/STIs ˆ STDs/STIs require medical examination & medical treat30 SZL2111 HIV/AIDs ment. Any person who has contracted STD/STI & is receiving treatment should also:  Receive counseling from a qualied health worker on how to avoid future infections  Take all medicines prescribed exactly according to all JKUAT the instructions SODeL  Inform all sexual partners of the need to get examined & treated   Abstain from further risky sexual behaviors Use condoms for protection 1.3.4. Why teenagers don't seek treatment JJ II J I J DocDoc I Back Close ˆ Lack of condentiality ˆ Hostility of service providers 31 SZL2111 HIV/AIDs ˆ Stigma attached to STIs/STDs ˆ Financial constraints for the youth who are unemployed e.g. anti-fungal drugs( diunisal pessaries) - clears most infection and it costs Ksh.1500 per tablet SODeL JKUAT ˆ Ignorance of availability of service providers NB: these concerns could be addressed through training service providers to be youth friendly & availing information, education & communication materials to the youth 1.3.5. FGM (Female Genital Mutilation) It's a destructive invasive procedure usually performed on girls before puberty. JJ II J I J DocDoc I Back Close It involves surgically removal of part or the whole clitoris using razor blades, knives, and scissors. Since the victims are young they are unable to give their informed consent. 32 SZL2111 HIV/AIDs FGM is forced on approximately 6000girls per day world wide. Because of poverty & lack of medical facilities the procedure is frequently done under less hygienic conditions & often without anaesthesia. A person who is not medically trained usually SODeL JKUAT circumcises about 20 girls of same age group. • Types of FGM 1. Sunna - its most widely practiced in sub-Saharan and middle east. It involves removal of the tip of the clitoris. 2. Intermediate-it's where the whole clitoris and adjacent parts such as labia major and labia minor are removed. 3. JJ II J I J DocDoc I Back Close Pharoic - it's the total removal of the clitoris, labia minor, labia major and where the two sides of the vulva are drawn together and then fastened leaving a small opening for 33 SZL2111 HIV/AIDs urinating and menstruating. This is especially in Somalia. • Eects of FGM leads to conditions that favours HIV survival SODeL JKUAT They include; JJ II J I J DocDoc I Back Close ˆ An abnormal anatomy with anatomical distortion ˆ Partial closure of the vagina ˆ Incomplete healing brought about by infections i.e. acids & organisms from ...
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