6 курс / Кардиология / Kartikeyan_HIV and AIDS-Basic Elements and Properties
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involved in IEC activities have an ethical obligation to provide correct scientific information. In their zeal to promote “desirable” behaviour, they must not create fear and panic or target groups known for high-risk behaviour for selective discrimination. While it is necessary to promote correct scientific information, there may be vested interests and self-appointed “guardians of public morals” in communities, who may oppose frank discussions on sex and sexuality. IEC activities ought to sensitise the public regarding nondiscrimination, acceptance, and respect for human dignity while dealing with HIV-infected individuals.
18.1.4 – HIV-Related IEC Activities
From 2006, students in 21,000 secondary and upper secondary schools in Bangladesh will be taught about HIV/AIDS as part of a “life skills” curriculum (UNDP, 2006). In India, NACO has launched a nationwide multimedia campaign. NGOs have been provided financial support to undertake awareness and intervention programmes for vulnerable groups such as sex workers, truckers, IDUs, street children, and migrant labourers. A National Counselling Training Programme has been launched to train grassroots-level counsellors. National AIDS Helpline has been set up with a toll-free telephone number “1097” so that the caller can avail of counselling services in an atmosphere that maintains privacy and confidentiality of the caller. School AIDS Education Programme provides lifestyle education and HIV-related information to high school students. A programme called “University talk AIDS” is targeting higher secondary and university students. School health curriculum and many training modules have been prepared, including one on counselling. The mass media have a role in inculcating moral values in society, and in educating the public about the link between alcohol use, substance abuse, and promiscuity.
18.2 – PREVENTING SEXUAL TRANSMISSION
Sexual intercourse is the most common mode of transmission of HIV. Promotion of safer sexual behaviour holds the key to preventing sexual transmission. Safer sex refers to any sexual act in which, there is no direct contact with body fluids of the sexual partner. Correct use of quality condoms effectively prevents contact with cervicovaginal secretions and semen. Studies in homosexual men (Detels et al., 1989) and heterosexual couples (Vincenzi, 1994) have shown that consistent use of condoms prevents transmission of HIV.
18.2.1 – Preventive Advice
Target groups for preventive advice include all patients with STIs, MSM, persons with multiple sex partners, sex workers, IDUs, persons seeking contraceptive advice, and overseas travellers (Bradford et al., 1997). Techniques for preventive advice include:
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(a)Taking a detailed sexual history to assess the risk of acquiring HIV infection
(b)Using explicit and clear messages that individuals can understand
(c)Dispelling myths and erroneous beliefs
(d)Providing tailor-made preventive advice to suit the individual’s needs
18.2.2 – Partner Counselling
Synonyms: Contact tracing and partner management. Based on the information provided by the “source client” (the STIor HIV-infected individuals), his or her sexual and/or drug-using partners are identified, located, investigated, and treated. It requires the cooperation of the source client. Partner counselling has been used as a public health response in case of STIs such as syphilis and gonorrhoea (UNAIDS & WHO, 2000). In the context of control of HIV epidemic, the objective is to encourage the partners to come in for HIV counselling and testing. Where possible, confidentiality of the source client is maintained and partner counselling is done with the source client’s consent. In many countries, the legal position regarding “partner notification” is not clear. If the HIVinfected person refuses to cooperate, health care providers have a moral and ethical responsibility to see that the partner is informed. The doctor may take the help of the public health authorities to trace the contacts (Bradford et al., 1997).
As per directives of the Supreme Court of India, “partner counselling” has been included as a component of India’s National HIV Policy. All HIV-infected individuals need to be encouraged to disclose their HIV status to their spouse/ sexual partners. However, HIV status should be disclosed to the spouse/sexual partners, only after proper counselling (NACO, Training Manual for Doctors). Due to intensive use of contact tracing, persons in high-risk groups have become wary of the health care system and have become reluctant to volunteer for HIV testing. Some HIV-infected persons may require professional assistance or support for notifying their partners (Bradford et al., 1997).
18.2.3 – Cluster Testing
In this method of case detection, the source client is asked to name other persons, of either sex, who move in the same socio-sexual environment. These persons are screened, using blood tests. This technique almost doubles the number of detected cases.
18.2.4 – Condom Promotion
Unprotected multipartner sexual activity is the major cause of HIV transmission in India. The disadvantages of free distribution of condoms are difficulty in ensuring supplies and doubts about their actual use. Condom promotion works best when targeted at those with high-risk behaviour. Promoting condom use among married couples has so far, met with little success. Health care personnel
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need to overcome their discomfort and reluctance to provide condoms to unmarried young males. Advertising through the mass media is directly related to demand for both socially marketed and public sector-distributed condoms. In communities where condom use is identified with promiscuity, strategies need to be devised to counter stigma of condom use.
Perception of risk of HIV infection and social acceptance are among the factors that influence condom use. The reported use of condoms is higher among unmarried persons as compared with the married, and with casual partners as compared with steady (or regular) partners. Even when aware of the risk of HIV infection, youth frequently do not use condoms and tend to establish the trustworthiness of their partners with criteria other than sexual history (Longfield et al., 2002). A four-country intervention programme in sub-Saharan Africa found that interventions increased risk perception of pregnancy only among females in two countries, but did not change the perceived risk of HIV infection (Agha, 2002).
Adolescent males are uncomfortable getting condoms where they might be recognised. In urban Botswana, youth were reluctant to get condoms from public sector clinics, even when available free of cost because health workers asked them questions about the use of condoms and their age. However, they were willing to get condoms from a public hospital where boxes of condoms were kept at a window with no questions asked (Meekers et al., 2001). Studies suggest that females can negotiate condom use more easily for prevention of pregnancy than for prevention of STIs. More studies are needed to identify the reasons youth prefer pharmacies, bars, or kiosks as outlets for condoms (Finger & Pribila, 2003).
18.2.5 – Dos and Don’ts Regarding Condom Promotion and Use
Potential clients ought to be informed that condoms prevent deposition of semen and urethral discharge, exposure to penile lesions, and unwanted pregnancies. Condoms should be used each and every time an individual has sexual contact (vaginal, anal, and oral) and with every partner (known or unknown). A condom should never be reused. Dates of manufacture and expiry should be checked before using the condom. The correct method of using condoms is to be demonstrated. Potential clients need to be told about common causes of condom failure like
(a)Damage to latex caused by exposure to heat, moisture, sunlight, and prolonged storage
(b)Failure to expel air in the “receptacle” or “teat” while wearing condom, which causes tearing
(c)Incorrect use, under influence of alcohol and/or drugs
Most condoms are pre-lubricated to increase sexual stimulation. Oil-based lubricants such as vaseline, oils, or creams can damage male and condoms. If the condoms are not lubricated, water-based lubricants should be used. Use of
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alcohol or drugs before or during coitus increases the risk of ignoring safer sex guidelines or faulty use of condoms (Fact Sheet 151, 2006).
18.3 – PREVENTING INJECTING DRUG USE
Harm Reduction: Harm reduction programmes encourage IDUs to abstain from using drugs. The drug users are provided with psychological assistance to abstain from drugs and substitution treatment with methadone. However, in some countries, substitution treatment with methadone is illegal. Although giving up drugs altogether is an ideal objective, harm reduction programmes recognise that total abstinence is very difficult or impossible in some cases. Harm reduction includes needle exchange programmes wherein drug users exchange dirty (used) needles for clean ones. If a supply of clean needles is available, drug users would be less likely to share needles and expose themselves to the risk of HIV infection. Some harm reduction clinics have encountered resistance from potential beneficiaries due to fear of government agencies (Kirby, 2006). The first comprehensive needle exchange programme for IDUs was established in Tacoma, Washington, DC, USA in 1988 (Kaiser Network, 2006). Nepal was the first developing country to establish a harm reduction programme with needle exchange (UNDP, 2006).
One of the strategies to contain the HIV epidemic is to impart information on risk of HIV transmission to IDUs, general public, policy makers, health care providers, and law enforcement personnel (Wodak & Dolan, 1997). However, in case of IDUs, the results of HIV education are not encouraging and studies have not revealed beneficial effects like changes in attitudes, behaviour or HIV seroprevalence (Des Jarlais et al., 1992). In countries where outbreaks of HIV infection have occurred among IDUs, the infection subsequently spread to rest of the population (Wodak & Dolan, 1997).
In view of their disappointing experiences in trying to prevent injecting drug use, some countries have launched needle exchange programmes where IDUs are provided sterile injecting equipment in exchange for used ones (Wodak & Dolan, 1997). In some states of Australia, imprisoned IDUs are supplied with bleach (hypochlorite-containing compounds) to decontaminate syringes and needles (Dolan et al., 1995). The effectiveness of bleach against HIV or hepatitis B/C viruses, when used under prison conditions is not known (Wodak & Dolan, 1997).
18.4 – PREVENTING BLOOD-BORNE TRANSMISSION
In 1982, the first case of possible HIV transmission through transfusion of blood or blood products was reported from California, USA (CDC, 1982).
Safety of Blood and Blood Products: India has adopted a multipronged approach for ensuring blood safety. The approaches include:
(a)Mandatory licensing of all blood banks and mandatory testing of every unit of blood for blood-borne infections such as HIV-1, HIV-2, hepatitis B/C, malaria, and syphilis
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(b)Establishing zonal blood testing centres (to provide linkage with other blood banks, and test blood samples from blood banks in the zone), and blood component separation facilities (to reduce the wastage of whole blood transfusion)
(c)Training blood bank staff and modernising blood banks in public and voluntary sectors
(d)Promoting voluntary blood donation
Blood donation by professional blood donors has been banned in India since 1 January 1998.
Other Measures: People in high-risk groups need to refrain from donating blood, semen, body organs, or other tissues. Injectable medications are to be avoided, unless absolutely essential. As far as possible, disposable gamma-sterilised needles and syringes should be used. Blood transfusion is to be given only when strictly indicated. Heat-treated Factors VIII and IX should be given to haemophiliacs, instead of coagulation concentrates. All health care providers ought to be trained in universal biosafety precautions and these should be strictly enforced in all health care facilities. Voluntary confidential testing, counselling, and referral services need to be provided at STI clinics, antenatal clinics, family planning centres, and at places where people belonging to high-risk groups gather for rest, or recreation such as resting points on highways for hijras (transgendered persons) and sex workers, or “gay clubs”. In some countries, only blood products from regular, voluntary donors are used since these donors have lower titres of markers for infectious diseases, including HIV antibodies (Wylie & Dodd, 1997). Other risk-reducing measures include autologous blood donation, directed, or designated donation such as parental donors for neonatal blood transfusion (Pink et al., 1994).
Limitations of Screening Procedures: The available screening procedures do not ensure zero-risk and the screening tests do not detect all the HIV variants (Wylie & Dodd, 1997). In the United States, estimates of risk of HIV transmission through blood or blood products vary between 1 in 450,000 donations to 1 in 660,000 donations (LaKritz et al., 1995). Blood from new donors is quarantined for a specific period. This is because the window period is currently at least 25 days (Busch et al., 1995). However, this policy may reduce the supply of blood to unacceptably low levels (Wylie & Dodd, 1997).
Possible Risk-Reducing Measures in Future: In the developed countries, due to screening of donated blood and heat-treatment techniques to destroy HIV in blood products, the risk of blood-borne transmission of HIV is extremely small (NIAID, 2005). Irrespective of the screening procedure employed, it is unlikely that zero-risk blood supply can be obtained. In spite of this, researchers are exploring new techniques for reducing the risk of HIV transmission through donated blood and blood products (Wylie & Dodd, 1997).
Reducing the “window period” – Before the formation of detectable anti-HIV antibodies, there is a brief period when HIV antigens are present in the blood
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(Wylie & Dodd, 1997). The test for p24 antigen, which is believed to have the potential to reduce the window period, was introduced in the United States in 1996. Introduction of this additional screening test costs US$ 20–50 million per year, but still does not meet the goal of zero-risk blood transfusion (Alter et al., 1990). However, in Thailand, where the prevalence of HIV infection in the donor population is as high as 4 per cent, p24 antigen screening has identified one additional infected donor for every 250 seropositive donors that were detected by existing screening tests (Mundee et al., 1994).
Molecular diagnostic techniques – Techniques such as PCR have the potential to reduce the window period for HIV by about 6–10 days. But, the existing molecular diagnostic techniques such as PCR, ligase chain reaction, and branched chain DNA do not permit large-scale, cost-effective screening of donated blood. Moreover, contamination of specimens can lead to false positive results. Currently, PCR will have to be used as a supplement and not as a substitute for HIV antibody screening tests.
Inactivating HIV – It is theoretically possible to inactivate HIV in plasma and blood cells by using solvent detergents, treating with heat, and by photoinactivation with methylene blue. But, in the immediate future, it is unlikely that virusinactivated plasma or blood cells would be available.
Blood substitutes – Synthetic oxygen-carrying products would be safer than transfusing human blood. Possible oxygen-carrying products under research include polymerised haemoglobin derivatives and fluorocarbons (Wylie & Dodd, 1997).
18.5 – ANTIRETROVIRAL THERAPY
Though no vaccine or cure is available so far, ARV drugs have been useful in prolonging the life of HIV-infected individuals, preventing MTCT in HIV-positive pregnant women, and for decreasing the complications of immune suppression. Postexposure prophylaxis (PEP) with ARV drugs should be also considered after accidental exposure to blood or body fluids for health care providers and for victims of rape. MTCT of HIV infection is negligible in the United States due to appropriate ARV treatment (NIAID, 2005). Certain ARV drugs have been approved for use in other countries under the President’s Emergency Plan for AIDS Relief (PEPFAR), a US$15 billion initiative announced by US President George Bush in 2003 to fight the HIV/AIDS pandemic. The objective of PEPFAR is to prevent 7 million new HIV infections, treat at least 2 million HIVinfected persons and care for 10 million HIV-infected individuals, AIDS orphans, and vulnerable children worldwide (FDA, 2006).
18.6 – SPECIFIC PROPHYLAXIS
Universal biosafety precautions and management of biomedical waste are to be enforced in health care facilities. Concurrent disinfection and decontamination involves the disinfection of all materials and equipment contaminated with blood and body fluids, irrespective of the patient’s HIV serostatus.
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Prevention of Opportunistic Infections: In the absence of a preventive vaccine, specific prophylaxis will be currently directed at preventing opportunistic infections in patients with CD4 count below 200 cells per L. For preventing Pneumocystis pneumonia, the drug of choice is cotrimoxazole and alternative drugs are aerosolised pentamidine or dapsone. Rifabutin is used, after excluding presence of tuberculosis, to prevent M. avium intracellulare infection. Similar prophylaxis is feasible for other opportunistic infections such as cytomegalovirus retinitis. For preventing M. tuberculosis infection isoniazid may be given daily in the dose of 300 mg for 9–12 months, to all HIV-infected persons, who test Mantoux positive (taken as induration of more than 5 mm). But, NACO Technical Resource Group on Chemoprophylaxis has deferred isoniazid chemoprophylaxis till more scientific data is available in the Indian setting (Pathni & Chauhan, 2003).
18.7 – SEXUALLY TRANSMITTED INFECTIONS: DIAGNOSIS AND TREATMENT
(See Chapters 10 and 15 for details.)
18.8 – PRIMARY HEALTH CARE
HIV-related programmes should be integrated with all aspects of primary health care, including maternal and child health (MCH), family planning, and health education. On 1 February 1987, the WHO launched the Global Programme on AIDS (GPA) to support the development of National AIDS Control Programmes. The Global AIDS Program (GAP) of the Centers for Disease Control and Prevention supports HIV-related activities such as training, information exchange, programme for IDUs, programme for MSM, and cross-border programmes in five Asian countries – Cambodia, China, India, Lao PDR, Thailand, and Vietnam (CDC, 2006).
18.9 – TARGETED INTERVENTIONS
Pilot projects in India for targeted interventions include those for sex workers in Kolkata, MSM in Chennai, IDUs in Manipur, Nagaland, and Assam, and truck drivers in Rajasthan (NACO, Training Manual for Doctors). In Mumbai, the AIDS Workplace Awareness Campaign targets truck drivers at the regional transport authority, where the drivers get their licences renewed annually. Some projects include petrol pump employees and owners (Fredriksson-Bass & Kanabus, 2006).
18.9.1 – Sex Workers
Sex workers constitute a cost-effective target population for reducing new infections. In communities where commercial sexual activity is a delicate issue, the support of community leaders is essential. Peer educators are valuable partners
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in this strategy since sex workers tend to be wary of unfamiliar persons. This group utilises reproductive health services, if offered with primary health care. For promoting use of condoms, the condoms should be accessible and affordable and the sex workers should be trained in negotiating condom use with their clients (UNFPA, 1998).
Targeted intervention programmes that empower sex workers have demonstrated that HIV transmission can be curbed. Condom use among sex workers in Kolkata’s Sonagachi red-light area was about 85 per cent and HIV prevalence declined to less than 4 per cent in 2004, having exceeded 11 per cent in 2001. By contrast, in Mumbai, HIV prevalence among female sex workers has not declined below 52 per cent since 2000 (UNAIDS/WHO, 2005). This is probably because brothel-based sex workers in Mumbai are controlled by “madams”, pimps, and moneylenders making HIV prevention activities more difficult (Fredriksson-Bass & Kanabus, 2006).
18.9.2 – Out-of-School Youth
Targeted interventions work better if obstacles to free and frank discussion on sexual matters are overcome. Income generation schemes may be used as an entry point. Youth-friendly reproductive health services are to be linked to IEC activities. Promotion of sexual abstinence rarely works and peer student educators are not best placed for reaching this group. Condom promotion is the central component of strategies to prevent infection in sexually active youth. Health care personnel need to overcome their discomfort and reluctance to provide condoms to unmarried young males. In communities where condom use is identified with promiscuity, strategies need to be devised to counter stigma of condom use (UNFPA, 1998).
REFERENCES
Agha S., 2002, A quasi-experimental study to assess the impact of four adolescent sexual health interventions in sub-Saharan Africa. Int Fam Plann Perspect 28(2): 67–70, 113–118.
Alter H.J., Epstein J.S., Swanson S.G., et al., 1990, Prevalence of human immunodeficiency virus type 1 p24 antigen in US blood donors – an assessment of the efficacy of testing in donor screening. N Engl J Med 323: 1312–1317.
Bradford D., Kippax S., and Baxter D., 1997, HIV prevention in the community: sexual transmission. In: Managing HIV (G. J. Stewart ed.), North Sydney: Australasian Medical Publications.
Busch M.P., Lee L.L., Satten G.A., et al., 1995, Time course of detection of viral and serological markers preceding human immunodeficiency virus type 1 seroconversion: implications for screening blood and tissue donors. Transfusion 35: 91–97.
Centers for Disease Control and Prevention (CDC), 1982, Possible transfusion-associated acquired immunodeficiency syndrome (AIDS). Morb Mortal Wkly Rep 31: 652–654.
Centers for Disease Control and Prevention (CDC), 2006, Global AIDS Program. www.cdc.gov.27 February.
Des Jarlais D.C., Friedman S.R., Choopanya K., et al., 1992, International epidemiology of HIV and AIDS among injecting drug users. AIDS 6: 1053–1068.
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Detels R., English P., Visscher B.R., et al., 1989, Serum conversion, sexual activity, and condom use among 2915 HIV seronegative men followed for up to two years. JAIDS 2: 77–83.
Dolan K., Wodak A., and Penny R., 1995, AIDS behind bars: preventing HIV spread among incarcerated drug injectors (Editorial). AIDS 9: 825–832.
Finger W. and Pribila M., 2003, Condoms and sexually active youth. Youth Lens on Reproductive Health and HIV/AIDS. Arlington, VA: YouthNet, March 2003.
Food and Drug Administration (FDA), 2006, FDA News. Washington, DC: US Department of Health and Human Services. www.fda.gov/cder/drug/infopage/atripla. 12 July.
Fredriksson-Bass J. and Kanabus A., 2006, HIV in India. www.avert.org. Last updated July 19. Kaiser Network, 2006, Global HIV/AIDS Timeline. www.kff.org/hivaids/timeline
Kirby M., 2006, AIDS in Eastern Europe and Central Asia. www.avert.org. Last updated 10 July. LaKritz G.M., Satten G.A., Alberle-Grass J., et al., 1995, Estimated risk of transmission of human immunodeficiency virus by screened blood in the United States. N Engl J Med 333: 1721–1725. Longfield K., Klein M., and Berman J., 2002, Criteria for trust and how trust affects sexual decision-
making among youth. Working Paper No. 451. Washington, DC: Population Services International.
Meekers D., Ahmed G., and Molatihegi M.T., 2001, Understanding constraints to adolescent condom procurement: the case of urban Botswana. AIDS Care 13(3): 297–302.
Mundee Y., Kamtorn N., Chaiyaphruk S., et al., 1994, Prevalence of HIV antibodies and p24 antigen among blood donors in Northern Thailand. Transfusion 34 (Suppl 635): Abstract.
NACO, Training manual for doctors. New Delhi: Government of India.
National Institute of Allergy and Infectious Diseases (NIAID), 2005, HIV infection and AIDS: an overview. NIAID Fact Sheet. Bethesda: National Institutes of Health. www.niaid.nih.gov/
National Institute of Health and Family Welfare (NIHFW), 1996, Inter-sectorial co-ordination and IEC Management. Module-5. New Delhi: NIHFW.
New Mexico AIDS Education and Training Center (NMAETC), 2006, Fact Sheet 151. Safer sex guidelines. University of New Mexico Health Sciences Center. www.aidsinfonet.org. Revised 18 July 2006.
Pathni A.K. and Chauhan L.S., 2003, HIV/TB in India – A public health challenge. JIMA 2003 101(3): 148–149.
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CHAPTER 19
SURVEILLANCE FOR HIV
Abstract
HIV surveillance in India involves annual cross-sectional survey of the same risk group in the same place over few years by unlinked anonymous testing by two ELISA, rapid, and simple (E/R/S) tests. Adequate numbers of representative samples are collected within the shortest possible time period. Patients attending STI clinics, IDUs, and MSM represent the high-risk groups in the population. The low-risk group comprises women attending antenatal clinics. Each sentinel site conducts an annual round of surveillance with 250 samples from high-risk groups and 400 samples from low-risk groups. From time to time, sentinel sites were increased to provide adequate representation to highand low-risk groups in urban and rural populations. As compared to point estimate, the range estimate is more scientific, reflects actual situation in the field, and also helps planners to formulate specific interventions for HIVaffected persons. Upper limit of the range was set at 20 per cent higher than the lower limit in order to take care of unaccounted number of HIV-positive persons in high-risk groups and the other age groups.
In 2005, the number of adults (aged 15–49) living with HIV in India was estimated to be 5.21 million, of whom 39 per cent were women. The adult HIV prevalence in 2005 (0.91 per cent) is comparable with that in previous 2 years. The prevalence of HIV infection in rural and urban inhabitants was 58.7 per cent and 41.3 per cent, respectively. The number of children under 15 years of age who were newly infected in 2005 was 59,007. The high-prevalence states were Andhra Pradesh, Karnataka, Maharashtra, Manipur, Nagaland, and Tamil Nadu. Gujarat, Goa, and Pondicherry were categorised as medium-prevalence states, while all the remaining states and Union Territories were low-prevalence states. HIV prevalence was more than 1 per cent among antenatal clinic attendees in 95 districts, including nine districts in lowprevalence states. The prevalence in this category has dropped to less than 1 per cent during the last 4 years in the high-prevalence state of Tamil Nadu while it has steadily declined from 2.08 per cent in 2003 to 0.88 per cent in 2005 in the low-prevalence state of Mizoram.
Key Words
Behavioural surveillance, Epidemiological surveillance, Epidemic Projection Package, Linked testing, Named case reporting, Participation bias, Point estimate, Range estimate, Second-generation surveillance, Sentinel surveillance, Unlinked anonymous testing, Unnamed case reporting
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