Category: Education

Presentation Description

No description available.


Presentation Transcript

Human Immuno Deficiency Virus Infection(HIV) : 

Human Immuno Deficiency Virus Infection(HIV) Dr.prakash Kafle,TUTH,Maharajgunj Kathmandu,Department of ICU /CCU 2067/8/17th


The acquired immunodeficiency syndrome (AIDS) was first recognised in 1981. It is caused by the human immunodeficiency virus (HIV-1). HIV-2 causes a similar illness to HIV-1 but is less aggressive and restricted mainly to western Africa. The viruses almost certainly originated from closely related African primate viruses, simian immunodeficiency viruses (SIVs). Sequence analysis has led to the estimate that HIV-1 was introduced into humans in the early 1930s. EPIDEMIOLOGY AND BIOLOGY OF HIV

Contd.. : 

Since 1981 AIDS has grown to be the second leading cause of disease burden world-wide and the leading cause of death in Africa, where it accounts for over 20% of deaths. Immune deficiency is a consequence of continuous high-level HIV replication leading to virus and immune-mediated destruction of the key immune effector cell, the CD4 lymphocyte Contd..


In 2004, the World Health Organization (WHO) estimated that there were 39.4 million people living with HIV/AIDS, 4.9 million new infections and 3.1 million deaths. A total of 64% of all persons with HIV live in sub-Saharan Africa, with South Africa accounting for one-third of AIDS deaths globally. Since 2002, the steepest increases have been seen in East Asia (50%), attributable largely to the epidemic occurring in China, and in Eastern Europe and Central Asia (40%), where alarming increases have been seen in the Ukraine, Latvia and Russia. In Vietnam, Thailand, Cambodia, Nepal and Myanmar, HIV is now well established. In India, it is estimated that 5.1 million persons are currently infected. In Tamil Nadu district 50% of sex-workers are infected, and in Manipur over 5% of pregnant women are positive. In northern India, HIV is well established in injection drug-users, of whom 25-50% are infected. Given that Asia is home to 60% of the world's population, these changes have huge implications GLOBAL EPIDEMIC AND REGIONAL PATTERNS

Slide 6: 

In the USA and northern Europe, the epidemic has predominantly been in men who have sex with men, whereas in southern and Eastern Europe, Vietnam, Malaysia, North-east India and China the incidence has been greatest in injection drug-users. In Africa, the Caribbean and much of South-east Asia the dominant routes of transmission are heterosexual and from mother to child (vertical). The economic and demographic impact of HIV infection in developing countries is profound as it affects the most economically productive and fertile ages and is also eroding the health and economic advances made in the last few decades. Unlike the situation in developed nations, fewer than 5% of patients in resource-poor countries are able to access antiretroviral drugs

Slide 7: 

The epidemic in industrialised nations is changing. Heterosexual transmission has become the dominant route, with racial and ethnic minorities representing an increasing fraction. High-risk sexual behaviour is also increasing in many developed countries, including in persons aware of their HIV-positive status.

Nepal. : 

Abot 64 thousands have been infected and only 16 thousands have been documented. Nepal.


FACTORS INCREASING THE RISK OF ACQUISITION OF HIV Common to all transmission categories . High viral load Lower CD4 cell count AIDS Seroconversion Vertical transmission . Older gestational age Prolonged rupture of membranes Chorioamnionitis Fetal trauma (e.g. scalp electrodes) Lower birth weight Vaginal vs elective caesarean delivery No peripartum prophylaxis First-born twin MODES OF TRANSMISSION

Slide 10: 

Breastfeeding Longer duration feeding Lower parity Younger age Mastitis Sexual transmission . Sexually transmitted infections (STIs), especially genital ulcers Cervical ectopy Receptive vs insertive anal sex Rectal or vaginal trauma Menstruation Male-male vs heterosexual sex Non-circumcised Increased number of partners

Slide 11: 

Injection drug use transmission . Sharing equipment Frequency of use Linked commercial sex Lower income Intravenous use Cocaine use Incarceration Occupational transmission . Deep injury Visible blood on device Previous arterial or venous device siting


Sexual Comprehensive sex education programmes in schools Public awareness campaigns for HIV Easily accessible/discreet testing centres Safe sex practices (avoiding penetrative intercourse, delaying sexual debut, condom use, fewer sexual partners) Targeting safe sex methods to high-risk groups Control of STIs Effective treatment of HIV-infected persons Post-sexual exposure prophylaxis Parenteral . Blood product transmission (donor questionnaire, routine screening of donated blood, blood substitute use) Injection drug use (education, needle/syringe exchange, avoidance of 'shooting galleries', sharing and support for methadone maintenance programmes PREVENTION MEASURES FOR HIV TRANSMISSION

Slide 13: 

Perinatal Routine 'opt-out' antenatal HIV antibody testing Counselling about planning/risks of pregnancy if HIV-seropositive Measures to reduce vertical transmission Occupational . Education/training (universal precautions, needlestick avoidance) Post-exposure prophylaxis

Slide 14: 

HIV is present in blood, semen and other body fluids such as breast milk and saliva . Exposure to infected fluid leads to a risk of contracting infection, which is dependent on the integrity of the exposed site, the type and volume of body fluid, and the viral load. HIV can enter either as free virus or within cells. The modes of spread are sexual (man to man, heterosexual and oral), parenteral (blood or blood product recipients, injection drug-users and those experiencing occupational injury) and vertical.

The transmission risk: : 

@ After exposure is over 90% for blood or blood products, @ 15-40% for the vertical route, @0.5-1.0% for injection drug use, @ 0.2-0.5% for genital mucous membrane spread and @ under 0.1% for non-genital mucous membrane spread The transmission risk:

Slide 16: 

World-wide, the major route of transmission (> 75%) is heterosexual. About 5-10% of new HIV infections are in children and more than 90% of these are infected during pregnancy, birth or breastfeeding. The rate of mother-to-child transmission is higher in developing countries (25-44%) than in industrialised nations (13-25%); postnatal transmission via breast milk may account for some of this increased risk. Of those infected vertically, 80% are infected close to the time of delivery and 20% in utero. Around 70% of patients with haemophilia A and 30% of those with haemophilia B had been infected through contaminated blood products by the time HIV antibody screening was adopted in the USA and Europe in 1985 WHO estimates that because of the lack of adequate screening facilities in resource-poor countries, 5-10% of blood transfusions globally are with HIV-infected blood.


HIV is a single-stranded RNA retrovirus from the Lentivirus family. After mucosal exposure, HIV is transported to the lymph nodes via dendritic, CD4 or Langerhans cells, where infection becomes established. Dendritic cells express various receptors . Free or cell-associated virus is then disseminated widely through the blood with seeding of 'sanctuary' sites (e.g. central nervous system) and latent CD4 cell reservoirs. With time, there is gradual attrition of the CD4 cell population, resulting in increasing impairment of cell-mediated immunity and susceptibility to opportunistic infections VIROLOGY AND IMMUNOLOGY

Contd… : 

HIV 1 “M”, ”O”, “N” Sub classes A to E group M ('major', world-wide distribution), group O ('outlier', divergent from group M) and group N (rare, highly divergent) types. Groups O and N are restricted to West Africa and may screen weakly positive or negative on routine antibody testing. Groups M and O can be subdivided further into subtypes “M” is further 14 types In Nepal common bariety is ‘C’ Contd…

Retro viral structure : 

Retro viral structure

Steps in replication : 

Attachment to CD4 receptors. Binding to co receptors[ CCR5 or CXCR4] Fusion Reverse transcription Integration Transcription(DNA copying from RNA) Translation Cleavage of polypeptide and assembly Viral release Steps in replication


Oral hairy leucoplakia Recurrent oropharyngeal candidiasis Recurrent vaginal candidiasis Severe pelvic inflammatory disease Bacillary angiomatosis Cervical dysplasia Idiopathic thrombocytopenic purpura Weight loss* Chronic diarrhoea* Herpes zoster Peripheral neuropathy Low-grade fever/night sweats HIV SYMPTOMATIC DISEASES

C/f of HIV infection : 

C/f of HIV infection

Natural history of HIV infectionFour Stages of HIV : 

Natural history of HIV infectionFour Stages of HIV

Natural history of HIV infectionFour Stages of HIV : 

1.Primary infection: is symptomatic in 70-80% of cases and usually occurs 2-6 weeks after exposure. Short, flu-like illness - occurs one to six weeks after infection no symptoms at all Infected person can infect other people 2.Asymptomatic infection: Asymptomatic infection follows and lasts for a variable period, during which the infected individual remains well with no evidence of disease except for the possible presence of persistent generalised lymphadenopathy (PGL, defined as enlarged glands at ≥ 2 extra-inguinal sites). Natural history of HIV infectionFour Stages of HIV

Slide 26: 

Lasts for an average of ten years This stage is free from symptoms There may be swollen glands The level of HIV in the blood drops to very low levels HIV antibodies are detectable in the blood

Slide 27: 

3.Mildly symptomatic disease :Mildly symptomatic disease indicates some impairment of the cellular immune system. These diseases correspond to AIDS-related complex conditions but by definition are not AIDS-defining The median interval from infection to the development of symptoms is around 7-10 years, although subgroups of patients exhibit 'fast' or 'slow' rates of progression. The symptoms are mild The immune system deteriorates emergence of opportunistic infections and cancers 4.Acquired immunodeficiency syndrome (AIDS): AIDS (CDC Classification category C disease) is defined by the development of specified opportunistic infections, tumours etc. The immune system weakens The illnesses become more severe leading to an AIDS diagnosis


Oesophageal candidiasis Cryptococcal meningitis Chronic cryptosporidial diarrhoea CMV retinitis or colitis Chronic mucocutaneous herpes simplex Disseminated Mycobacterium avium intracellulare Pulmonary or extrapulmonary tuberculosis Pneumocystis carinii (jirovecii) pneumonia Progressive multifocal leucoencephalopathy Recurrent non-typhi Salmonella septicaemia Cerebral toxoplasmosis Extrapulmonary coccidioidomycosis Invasive cervical cancer Extrapulmonary histoplasmosis Kaposi's sarcoma Non-Hodgkin lymphoma Primary cerebral lymphoma HIV-associated wasting HIV-associated dementia AIDS-DEFINING DISEASES

Opportunistic Infections associated with AIDS : 

Opportunistic Infections associated with AIDS Bacterial Tuberculosis (TB) Strep pneumonia Viral Kaposi Sarcoma Herpes Influenza (flu)


To all: CD4 count and Viral load Hepatitis B and C Ab HIVResistant Test Cervical Smear in women Hep A IgG Antibody Toxoplasma Ab Cytomegalovirus Ig G Ab Treponema Serology Genitourinary Medicine Screen INVESTIGATIONS

Slide 31: 

For CD4 < 200/mm3 CXR HCV-RNA Cryptococcal Ag Stool for Ova ,cyst and parasites. For CD4 < 100/mm3 CMV –PCR Dilated Fundoscopy Electroencephalogram(EEG) MycobacterialBlood Culture

Blood Detection Tests : 

Blood Detection Tests Enzyme-Linked Immunosorbent Assay/Enzyme Immunoassay (ELISA/EIA) Radio Immunoprecipitation Assay/Indirect Fluorescent Antibody Assay (RIP/IFA) Polymerase Chain Reaction (PCR) Western Blot Confirmatory test

Laboratory confirmation : 

# Serology using the Commercialy prepared Enzyme linked imunosorbent Assay(ELISA) Test result Negative:Repeate Test after 3 months Test result positive:Confirm the diagnosis byEither Doble immuno assay OR By WESTER BLOT Test #Nucleic Acid Amplification test(PCR):If seroconversion suspected confirming Vertical transmission Laboratory confirmation

Urine Testing : 

Urine Testing Urine Western Blot As sensitive as testing blood Safe way to screen for HIV Can cause false positives in certain people at high risk for HIV

Oral Testing : 

Oral Testing Orasure The only FDA approved HIV antibody. As accurate as blood testing Draws blood-derived fluids from the gum tissue. NOT A SALIVA TEST!

Treatment : 

Drugs uses Indications to start drugs Frist line drugs and alternatives Common side effecst Prevention Post exposure prophylaxis Treatment

Drugs used in HIV/AIDS : 

DRUGS Group NUCLEOSIDE REVERSE TRANSCRIPTASE INHIBITORS (NRTIs): . Zalcitabine (ddC) Didanosine (ddI) Lamivudine (3TC) Zidovudine (ZDV) Stavudine (d4T) Abacavir Emitricitabine (FTC) Non-nucleoside reverse transcriptase inhibitors (NNRTIs) . Nevirapine Efavirenz Delavirdine1 Protease inhibitors (PIs) . Indinavir2 Ritonavir Nelfinavir Lopinavir3 Atazanavir2 Fosamprenavir2 Saquinavir2 Amprenavir1,2 Tipranavir1 Others Tenofovir Enfuvirtide (T-20) Drugs used in HIV/AIDS

US departmant of Health And Human Service Guideline of HIV/AIDS2009 : 

When to Start Therapy: US departmant of Health And Human Service Guideline of HIV/AIDS2009

Slide 39: 

RECOMMENDED COMBINATION TREATMENTS FOR THE NAÏVE PATIENT1 Regimen A B C Preferred Efavirenz Zidovudine Lamivudine Lopinavir/ritonavir Abacavir Emitricitabine Tenofovir Didanosine Alternative Fosamprenavir/ritonavir Saquinavir/ritonavir Nevirapine2

Summary : 

HIV is caused by Retro virus. It is the burning health problem of the world Deranged immunity is main culprit Its not curable till to date HIV/AIDS day Dec.1st of every year Monogamous sex partner prevents it Pneumocysttistis jiruvaci pneumonia is commonest chest infection. Latest guideline suggest that what ever be the CD4 cont ,HAART can be started. Summary

Contd…….. : 

Four ways to prevent yourself:: Abstinence Monogamous Relationship Protected Sex Sterile needles Contd……..

Abstinence : 

Abstinence It is the only 100 % effective method of not acquiring HIV/AIDS. Refraining from sexual contact: oral, anal, or vaginal. Refraining from intravenous drug use

Monogamous relationship : 

Monogamous relationship A mutually monogamous (only one sex partner) relationship with a person who is not infected with HIV HIV testing before intercourse is necessary to prove your partner is not infected

Protected Sex : 

Protected Sex Use condoms (female or male) every time you have sex (vaginal or anal) Always use latex or polyurethane condom (not a natural skin condom) Always use a latex barrier during oral sex

Sterile Needles : 

Sterile Needles If a needle/syringe or cooker is shared, it must be disinfected: Fill the syringe with undiluted bleach and wait at least 30 seconds. thoroughly rinse with water Do this between each person’s use

Thank You! : 

Thank You!

authorStream Live Help