Q. What is HIV ?
HIV is Human Immuno-deficiency Virus, (a disease of humans where there is deficiency of immunity). It is a RNA virus. It is a special kind because it forms DNA from RNA (generally RNA is formed from DNA), this is due to the presence of the enzyme called reverse transcriptase.
HIV belongs to the ‘retrovirus’ family, so the therapy against this virus is called ‘anti-retroviral therapy.’
Q. Then what is AIDS ?
AIDS is Acquired Immune Deficiency Syndrome which means a collection of symptoms and infections resulting from the damage to the immune system caused by the human immunodeficiency virus (HIV).
Since the immune system is the main ‘defense’ of the body against the infections, the person with damaged immunity because of HIV are more prone to develop various infections and cancers. Many bacterias, viruses and fungi, which rarely infect normal human beings can easily infect the patients in AIDS due to HIV.
So, a person who has recently been infected with HIV, is not having AIDS. It takes 2-10 years for a person to land into AIDS. So HIV doesn’t mean AIDS, but AIDS means HIV infection!
In short, AIDS is the end stage of HIV infection.
When cd4+ count falls to 200 or less per ml of blood, it is called AIDS.
Q. How does the HIV cause damage to the immunity of the body?
HIV is an amazing virus, it damages the main cell of immune system called the CD4+ lymphocytes (a kind of white blood cells). You might have heard about the CD4+ count, this is a blood test done to count the number of CD4+ cells in the patient with HIV/AIDS. The less the number of CD4+ cells, the patient is more prone to get infected with various infections.
Q. How does AIDS spread?
Here is the catch. HIV spreads, not the AIDS. HIV is a virus that can be transmitted from one person to another. But the AIDS, which is a collection of symptoms and infections cannot be transmitted from one person to another. But as the person with AIDS has maximum number of HIV (virus), he can transmit the HIV to another person.
Q. Ok, so AIDS doesn’t spread, what spreads is the HIV. Then tell me how does this virus (HIV) transmit from one person to another?
1. Blood Products: Blood products generally includes the donated blood and the other types of blood products like platelets, RBC, Plasma transfusion from a person infected with HIV to a normal person. There is a 9 out of 10 chance of spreading HIV this way. (90%)
2. Mother to Child: There is 15 – 40% chance of spreading HIV from mother to child when a HIV infected mother gives birth to a baby.
3. IV Syringe Sharing: There is a 0.5 –1 % chance of transmitting HIV by sharing syringes between injectable drug users. If 1000 HIV infected addicts share their syringes with a non-HIV addicts, 5 to 10 of them will be getting HIV. This number might seem less, but imagine how many times does an addict share his syringe? yes, multiple number of times.. so, the risk increased sharply.
4. Sexual Intercourse: The chances of transmitting HIV during sexual intercourse varies from 0.1% to 1% depending on type of sexual intercourse. The presence of other sexually transmitted diseases (STDs like Syphillis, Gonorrhoea) increases the chances of transmitting HIV. The risk also is higher for females (receptive) than for males (insertive).
5. Needle Prick Injuries: Chances of transmitting from the accidental needle prick is 0.1% in healthcare setup. (eg. If I get pricked by the needle used in a HIV patient to draw blood.)
* According to Wikipedia, the chances per 10,000 exposures is:
Blood Transfusion: 9,000
Childbirth: 2,500
Needle-sharing injection drug use: 67 (though the number looks very less, this is a ratio for a single exposure, the addicts have multiple exposures per day!!)
Receptive anal intercourse*: 50 (receptive means, a man/woman having anal intercourse)
Percutaneous needle stick 30 (this is accidental needle prick to the doctors/nurses)
Receptive penile-vaginal intercourse* :10
Insertive anal intercourse* 6.5 (this is a risk for the male who is having insertive intercourse with an infected male/female)
Insertive penile-vaginal intercourse* 5 (this is the risk for the male having vaginal intercourse with a HIV infected woman)
Receptive oral intercourse* 1
Insertive oral intercourse* 0.5
* assuming no condom use
Q. Anything about the history of HIV?
HIV is thought to have originally transmitted to humans from monkeys. There is no proved theory about the transmission, but the most approved thoery is that it was transmitted to humans in Africa when some people hunted monkeys. HIV was first detected in the year 1981. The total number of deaths in the world due to HIV/AIDS till now is over 20 million. In 2004, the WHO estimated that there were 39.4 million people living with HIV/AIDS, 4.9 million new infections and 3.1 million deaths.
Q. What is the scenario in Nepal?
In Nepal, first case of HIV was diagnosed in 1988. According to Annual Health Report of Nepal 2004/2005, there are 4,593 reported cases of HIV/AIDS in Nepal. But the NGOs/INGOs estimate that there are more than 62,000 people living with HIV/AIDS in Nepal at end of 2004.
In Nepal, by far the largest number of reported HIV infection come from men who have been clients of sex workers (53.02%)
followed by, injection drug users (20.10%)
then female sex workers (10.73%)
and blood recipients (1%)
Most of the infected people are in the age group of 20 to 39 years.
Highest reported number of HIV infection at the age group of 30 to 39 years.
These data are taken from Annual health report 2004/2005 published by Department of health services, Nepal.
Q. How is HIV infection diagnosed?
Various tests are available for the diagnosis. Commonly used tests to detect HIV infection are:
1. ELISA Kits (Enzyme Linked Immune Sorbant Assay, they are simple plastic kits where we put a drop of blood and wait for a few minutes, and if a line appears its HIV positive. It can be done anywhere without any sophisticated instruments)
2.Western Blot (This is the confirmatory test for HIV. It is complicated method that can only be done in a lab.)
3. Hi-fi things like PCR are also available, but aren’t practical for country like ours, they are used for research.
Q. I have heard of something called Window Period. What is that?
Both of the above tests detect HIV activity in blood. But it takes about 2 to 6 months to appear in the blood of the person after he has been infected. This period of 2 to 6 months is called “window period”. During window period HIV cannot be detected in the blood but the infected person can transmit HIV to others during this period. So, this window period is a very vital period, if HIV is suspected, the test must be repeated after 3-4 months.
Q. What happens to a person after he is infected with HIV?
Most of these patients get infections caused by bacteria, viruses, fungi and Parasites. HIV affects nearly every organ system. HIV doesn’t produce any specific symptoms, but the person is more prone to get infected from common illnesses like pneumonia, tuberculosis etc. A person with HIV takes 5-10 years to land into AIDS.
As the person with HIV starts having AIDS, he also has increased risk of developing various cancers such as Kaposi’s sarcoma, cervical cancer and cancers of the immune system known as lymphomas.
Additionally, people with AIDS often have systemic symptoms of infection like fevers, sweats (particularly at night), swollen glands, chills, weakness, and weight loss. After the diagnosis of AIDS is made, the current average survival time with antiretroviral therapy (as of 2005) is estimated to be more than 5 years, but because new treatments continue to be developed and because HIV continues to evolve resistance to treatments, estimates of survival time are likely to continue to change. Without antiretroviral therapy, death normally occurs within a year. Most patients die from opportunistic infections or malignancies associated with the progressive failure of the immune system.
(One of HIV infected guy from Dharan once said.. “Sir, I am fully optimistic about life, I am sure to survive for next 10-15 years with the medicines available now… and it is sure that there are better drugs to come before I die.. so .. don’t think I am going to die soon..”)
Q. I heard that HIV is not treatable, then what is anti-retroviral therapy?
Yes, you are right, we can’t ‘un-infect’ someone who has HIV, but we can try to elongate the life of patient with AIDS.
And talking about anti-retroviral therapy, this is a therapy against the HIV (a retrovirus), so therapy against HIV is called Anti-retroviral therapy. In antiretroviral therapy, we try to stop the virus from damaging the immune system. The development in the science hasn’t been able to completely control the damage done by HIV, but we are surely trying to decrease the effect. (so that CD4+ count ie the immunity of our body doesn’t go below the desired level.)
Antiretroviral treatment is also available from the different government hospitals in Nepal. CD4+ counter facilities are also being started in Nepal. (BP Koirala Institure of Health Sciences, Dharan is another place besides Teku Hospital)
different medicines are avaliable are:
Group 1 .Nucleoside reverse transcriptase inhibitor
drugs are, Zidovudine, Didanosine, Zalcitabine, Lamivudine etc
Group 2. Non-nucleoside reverse transcriptase inhibitor
eg, Nevirapine, Efavirenz
Group 3.Protease inhibitor
eg,Indinavir, Ritonavir, Nalfinavir, Squinavir etc.
All these drugs can only prolong the life by one to few years but cannot cure HIV/AIDS. They are expensive drugs and have lots of side effects.
So, prevention of HIV is most important for countries like ours.
Q. If some HIV infected women wants to give birth to a baby, can she?
Yes she can! But there are chances that the baby might get HIV. The advancement in the treatment has brought the chances of infection to less than 1%. She should be put on medications.
The chances (according to our books!)
Zidovudine(a drug for HIV) only-reduces risk of transmission to 8.3-18%
zidovudine + Lamivudine(yet another drug) -reduces risk to 2.6-10.2%
Zidovudine + Caesarean section (when baby is delivered by operation)- reduces risk to 0.8-1.8%
(If these things are conducted properly, the chances are minimal.)
Q. So, the only logical thing that can be done is Prevention. How can we prevent HIV spread?
Yes, the only logical thing is to prevent HIV spread. This is not a big problem if the public is aware. As we have already known about the modes of infection, preventing those modes of infections is the solution.
Avoiding AIDS as easy as… ABC
A bstain
B e faithful
C ondoms
Reference for all these information are;
1.Davidson’s principle and practice of medicine(20 th edition)
2.Text book of microbiology,by Anantanarayan and Paniker)
3.Essentials of medical pharmacology by K.D.Triphathi
4. Wikipedia (www.wikipedia.com)
5. Various internet sources
6. Teacher lectures ( sorry, I can’t recall the names 
)
any queries, please be free to email me. would love to answer your queries.
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