Taking Charge of Your Health

topic of this presentation is HIV-AIDS first of all, we will discuss about Human Immunodeficiency Virus (HIV) and its structure See in the diagram, this is a lipid membrane and some glyco-proteins are associated with it these glyco-proteins help virus attaching to the cell membrane receptors and infecting it and it is a protein capsid it covers viral genome HIV is a retro-virus retro-virus means a virus that has RNA as the genome HIV has two molecules of single stranded (ss)RNA If you are a medical aspirant, this information might be useful some enzymes are also associated with RNA, these are called reverse transcriptase after entering the host cell, these enzymes help RNA to transform into DNA that DNA will integrate itself with host DNA and will help virus replicate with the help of this diagram, we will now understand how HIV infects a host cell and replicates in a host cell Virus infects its host cell in two ways see here in the diagram that it has attached itself to the membrane receptors of the host cell with the help of glyco-proteins staying outside, it has released capsid into the host cell second way could be the entire virus enters the host cell through endocytosis if the entire virus enters the host cell, then lysosome digests the outer layer of lipid and capsid is released along with RNA and reverse transcriptase reverse transcriptase will synthesize DNA molecule from RNA through a process called reverse transcription now this DNA integrates with host DNA using the host cell machinery, it will transcribe its DNA into numerous copies of RNA and as a result of transcription two types of RNA will be formed genomic RNA and mRNA mRNA will form protein molecules these protein molecules will assemble along with genomic RNA and viral particle will be formed a mature virus comes out of the host cell to infect other neighboring host cells we have just discussed infection and replication of Retrovirus with the help of a diagram we have summarized the whole process here in the form of a flowchart this flowchart can be very useful if you are preparing for board exam this flowchart has been asked in the form of ‘fill in the blanks’ type questions let’s discuss Some Important Points related to HIV HIV infects macrophages first and replicates inside the macrophages to increase its number that’s why macrophages are aka “HIV factory” as it increases its number by replicating in macrophages now it starts infecting T cells in T cells also it will undergo replication in the same way gradually the number of T cell decreases because host cells burst as a result of tremendous increase in their number inside the cells and also, they (host cell) are not able to perform their functions as virus has taken over its cellular machinery and utilizing it for its own functions in this way number of T cells keeps on decreasing we have discussed in the chapter “Human diseases” that T cells play very important role in our immune system therefore the immune system of HIV positive people gradually weakens over time now we will differentiate between AIDS and HIV positive what’s the difference when we call this is an HIV positive person and that is an AIDS patient there is a difference between these two terms being HIV positive means – the moment a person contracts HIV the person has become HIV positive since that moment but as the HIV progresses and increases its number in that person’s body the number of T helper cells will decrease when the number of T helper cells falls below 200 per cubic milli meter in the blood now we will call that person an AIDS patient here I must tell you that normal T helper cell count in a healthy person is 1200 per cubic milli meter of blood it means that when this count falls below 200 then the immunity of that person weakens to great extent now we start calling such HIV positive person, an AIDS patient after understanding the meaning of AIDS, we must now learn about Opportunistic infections what are Opportunistic infections bacteria are also there in our body and they trying their best to cause disease to our body but our immune system fights these microbes for 24×7 and protects us from any kind of infection for example this Mycobacterium can be present in the lungs of even a healthy person but our immune cells are fighting these bacteria consistently and keep its number so low that it is not able to cause any disease but if our immune cells” number falls too low then they will now not be able fight Mycobacterium effectively and this Mycobacterium will take advantage of this opportunity and can cause tuberculosis to the patient such infections are called Opportunistic infections now we will discuss that how HIV is transmitted from infected person to a healthy person first factor is sexual contact intercourse with an unknown partner and he/she is infected HIV will be transmitted to the body of a healthy person during pregnancy- if the mother is infected HIV crosses placenta and can cause infection to the developing fetus and after birth if a infected mother feeds newborn then HIV enters the body of infant through milk drug addicts who use needle indiscriminately chances of HIV transmission in their body are quite high due to occupational exposure – for example nurses might get pricked with the same needle during administering medicine intravenously that nurse might get infection blood transmission or organ transplantation might also transmit HIV into the body of a healthy person but these are very rare cases because blood is tested for HIV under blood bank policy we must also know that what factors are not at all responsible for transmission of HIV which factors do not transmit HIV because this information is also equally important so that we could save ourselves from any kind of prejudice it does not transmit through water and air does not transmit through person’s saliva, sweat and tear it does not transmit through mosquito bite and through pets does not transmit through sharing toilets and casual contacts shaking hand, hugging and sharing food these could never be the reasons of spread of HIV we must stay way from any kind of prejudice to keep up a healthy society and we could become a part of a healthy society before discussing diagnostic test for HIV, we must learn about ‘window period’ what is ‘window period’ Window period is the time between HIV infection and the point when the test will give an accurate result. test will show negative result because HIV lives in our body hidden for a few weeks therefore it will not positive result in the diagnostic test this period is called window period which comprises of about 4 weeks during this period if ELISA and western blot tests are done then these tests will give negative result even though the person has acquired HIV infection, and is highly infectious also the person can transmit HIV to a healthy person this is called window period these three diagnostic tests are available for HIV Enzyme Linked Immune Sorbent Assay (ELISA), Western Blot, and Polymerase Chain Reaction (PCR) these two test ELISa and western blot has a limitation that these give negative result during window period but PCR can give us immediate results if a surgeon gets exposure of HIV during surgery through needle prick or due to any other reason that surgeon can immediately make out the status of HIV infection through PCR HIV can be cured 100% if it is detected in the body at very early stage then such surgeon can cure himself completely form any kind of HIV infection Links of animated videos of ELISA, Western Blot and PCR are given in the description box. some drugs are available for the treatment of HIV but before discussing these we must understand difference between cure and treatment cure means treating a disease completely but only treatment of the incurable disease is possible progression of the disease can be slowed down with the help of drugs and the effect of discomfort due to that disease can be minimized patient can be made comfortable to some extent treatment of HIV is possible but the cure is not possible now we will see how these drugs act some drugs block binding of virus to host cell membrane receptors some drugs Inhibit reverse-transcriptase thus blocking conversion of retroviral RNA into DNA and also block integration of viral-DNA to host DNA in this way some drugs slow down the progression of HIV Link of animated video of HIV Replication & Treatment is given in the description box. right knowledge about AIDS is a very effective way to prevent AIDS because if we have the right information then there will be no prejudice and we will not ill-treat any AIDS patient so that he does not develop ant stigma and this is very important for developing a healthy society keeping this point in mind, government and NGOs run some AIDS awareness campaigns one of such campaign is Stigma and Discrimination in the Workplace Link of video on AIDS Awareness Campaign “HIV/AIDS: Stigma and Discrimination in the Workplace” is given in the description box. I want to tell my students that keep right information about AIDS save yourself from prejudice and an AIDS patient from stigma so that a healthy society develops study these two pictures and compare that to what extent AIDS transmission occurs in the society only due to ignorance according to this study, HIV is transmitted from infected mother 3.2 million children during pregnancy and breast-feeding even though treatment is available if pregnant woman is given proper pre-natal care ant treatment then that infected mother cannot transmit HIV infection to the developing fetus but for that, care and treatment should be given during pregnancy Link of video on AIDS Awareness Campaign “Pregnancy and HIV: Testing and Counseling” is given in the description box. NACO – National AIDS control Organization is an NGO which runs AIDS awareness campaigns this organization used a very innovative method to spread AIDS awareness in the society they started some programs on radio they clubbed AIDS awareness campaign with entertainment these programs inform people about AIDS along with super hit movie songs many such campaigns were run through govt. and also NGOs to disseminate right information about AIDS to minimize fear and prejudice for AIDS in this flowchart, role of healthcare services and AIDS awareness campaigns has been integrated if there is proper AIDS awareness in the society then fear, prejudice and discrimination will be minimized due to which HIV positive people will be able to talk about the infection openly and will seek treatment as soon as possible to receive better care and treatment and it will lead to better prevention and treatment of HIV in the society

8 thoughts on “HIV-AIDS | Human Health & Disease Part 7 | Biology Class 12 | HINDI

  1. 👍👍👍👍👍👍😄😄😄😄😄😄😆😆😆 thank u sooo much for making bio soo easy to understand !!!

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