Hiv Takes Control Of T Cells
Once inside the cell, the capsid dissolves, liberating the viral RNA and the reverse transcriptase. Now, in order to infect the cell, the viral RNA needs to travel into the T cell’s nucleus . However, for that to happen, an important transformation needs to take place.
Normally, the T cell’s nucleus communicates with the rest of the cell by transforming DNA into RNA and sending it out of the nucleus. The genetic material’s passport to leave the nucleus is to be transformed into single-stranded RNA. In the same fashion, the passport to enter the nucleus is to be transformed into double-stranded DNA.
Viral RNA needs to become DNA in order to start the replication process. Reverse transcriptase allows the RNA to borrow material from the cell and to “write backwards” a chain of viral DNA.
HIV is considered a retrovirus because of its capacity to transform RNA into DNA, reversing the natural process that takes place in cells. This is accomplished by the reverse transcriptase. Retroviruses are a special family of viruses to which only a few known viruses belong .
Hiv Effects On The Immune System
Your immune system has many types of white blood cells that fight infection. HIV gets inside a kind called CD4 cells and makes copies of itself. The virus kills the cell, and the new viruses go off to find more.
Your body responds by making more CD4 cells, but after a while, it canât keep up with the virus. This makes your immune system weak. Youâre more likely to get sick, even from common germs. Infections last longer, are more severe, and might come back more often.
If you follow your doctorâs directions with ART, it knocks out HIV, stopping it from infecting more CD4 cells and from weakening your immune system.
What Are The Factors That Affect Disease Progression
The most important factor affecting HIV progression is the ability to achieve viral suppression. Taking antiretroviral therapy regularly helps many people slow the progression of HIV and reach viral suppression.
However, a variety of factors affect HIV progression, and some people progress through the phases of HIV more quickly than others.
Factors that affect HIV progression can include:
- Ability to achieve viral suppression. Whether someone can take their antiretroviral medications and achieve viral suppression is the most important factor by far.
- Age when symptoms start. Being older can result in faster progression of HIV.
- Health before treatment. If a person had other diseases, such as tuberculosis, hepatitis C, or other sexually transmitted diseases , it can affect their overall health.
- Timing of diagnosis. Another important factor is how soon a person was diagnosed after they contracted HIV. The longer between their diagnosis and treatment, the more time the disease has to progress unchecked.
- Lifestyle. Practicing an unhealthy lifestyle, such as having a poor diet and experiencing severe stress, can cause HIV to progress more quickly.
- Genetic history. Some people seem to progress more quickly through their disease given their genetic makeup.
Some factors can delay or slow the progression of HIV. These include:
Living a healthy lifestyle and seeing a healthcare provider regularly can make a big difference in a persons overall health.
Read Also: How Fast Can You Test For Hiv
Testing For Drug Resistance
HIV often changes or mutates in the body. Sometimes these changes make the virus resistant to certain medicines. Then the medicine no longer works.
Medical experts recommend testing the blood of everyone diagnosed with HIV to look for this drug resistance.footnote 7 This information helps your doctor know what medicines to use.
You also may be tested for drug resistance when:
- You are ready to begin treatment.
- You’ve been having treatment and your viral load numbers stop going down.
- You’ve been having treatment and your viral load numbers become detectable after not being detectable.
How Can You Prevent Hiv
HIV is often spread by people who don’t know they have it. So it’s always important to protect yourself and others by taking these steps:
- Practice safer sex. Use a condom every time you have sex until you are sure that you and your partner aren’t infected with HIV or other sexually transmitted infection .
- Don’t have more than one sex partner at a time. The safest sex is with one partner who has sex only with you.
- Talk to your partner before you have sex the first time. Find out if he or she is at risk for HIV. Get tested together. Use condoms in the meantime.
- Don’t drink a lot of alcohol or use illegal drugs before sex. You might let down your guard and not practice safer sex.
- Don’t share personal items, such as toothbrushes or razors.
- Never share needles or syringes with anyone.
If you are at high risk for getting infected with HIV, you can take antiretroviral medicine to help protect yourself from HIV infection. Experts may recommend this for:footnote 1
- People whose sexual practices put them at high risk for HIV infection, such as men who have sex with men and people who have many sex partners.
- People who inject illegal drugs, especially if they share needles.
- Adults who have a sex partner with HIV.
To keep your risk low, you still need to practice safer sex even while you are taking the medicine.
Recommended Reading: The History Of Hiv And Aids In The United States
Alcohol Hiv And The Mucosal Immune System
Many of the SIV studies examining the connection between alcohol, HIV, and the immune system have focused on the mucosal immune system, consisting of cells that reside in the tissues lining various parts of the body, particularly the gastrointestinal tract, genital tissue, and the lung. These areas represent a critical if not primary site of HIV infection. Further, converging evidence suggests that AUD influences mucosal tissue in a way that potentially increases HIV disease transmission and adversely affects disease pathogenesis, resulting in accelerated disease progression.
When Is Drug Therapy Necessary
The decision to start ARVs should always be made in consultation with a doctor. There are various guidelines worldwide as to when to start therapy. A consistent CD4+ count that is recorded at below 350, is considered low and should be monitored on a regular basis. At levels of 200250, an individual is at serious risk of opportunistic infections and a doctor may also recommend that antibiotics be taken to prevent PJP . Therapy should definitely be initiated at any CD4+ count below 350.
In South Africa, in accordance with best practice around HIV treatment, ARV treatment begins from the moment a person tests positive for HIV.
Once therapy is started, the CD4+ count may start to rise, which could reflect an improvement in immune function and the bodys ability to fight infections. Once the CD4+ count rises above 350 and is maintained above this level, your body is better equipped to fight infections.
Regular monitoring of CD4+ count and a rise in viral load helps to determine whether ARV treatment is working. As long as the trend is upward or stable, then there is a positive indication of the effectiveness of the treatment. A consistent fall in CD4+ count may indicate that the treatment is becoming less effective. Importantly, any decision to change treatment should be taken in conjunction with a viral load test. Once therapy has started, it is normally recommended that CD4+ counts be done every 6 months .
Recommended Reading: Does Prep Prevent Transmission Of Hiv
Microbial Translocation In Alcohol And Hiv
Both alcohol consumption and HIV/SIV infection seem to disrupt the intestinal lining, disrupt intestinal barrier function, and lead to microbial translocation. Indeed, both short- and long-term alcohol consumption can cause intestinal barrier permeability and movement of luminal bacterial antigens into systemic circulation through the blood, resulting in chronic inflammation and eventually liver damage . Research also finds microbial translocation in the blood of HIV patients and SIV-infected macaques in the absence of alcohol as evidenced by the presence of lipopolysaccharide endotoxins . In fact, bacteria leaking through damaged intestinal barriers as a result of HIV-induced destruction of the key regulatory CD4+ T cells seems to be responsible for the systemic immune activation that is a hallmark of HIV infection and is a better predictor of HIV disease than plasma viral loads . Indeed, levels of systemic activation appear to play a major role in the susceptibility to infection and disease progression .
Together, these findings suggest that the adverse effects of alcohol and HIV infection on microbial translocation may be additive. In addition, the inflammation and epithelial cell barrier damage that alcohol and its byproducts inflict on the intestinal mucosa may result in greater levels of mucosal and systemic immune activation, rendering patients more vulnerable to HIV transmission.
Who Is At Risk For Hiv Infection
Anyone can get HIV, but certain groups have a higher risk of getting it:
- People who have another sexually transmitted disease . Having an STD can increase your risk of getting or spreading HIV.
- People who inject drugs with shared needles.
- Gay and bisexual men.
- Black/African Americans and Hispanic/Latino Americans. They make up a higher proportion of new HIV diagnoses and people with HIV, compared to other races and ethnicities.
- People who engage in risky sexual behaviors, such as not using condoms.
Factors such as stigma, discrimination, income, education, and geographic region can also affect peoples risk for HIV.
Also Check: How Can You Catch Hiv Aids
Whats The Difference Between Hiv And Aids
The difference between HIV and AIDS is that HIV is a virus that weakens your immune system. AIDS is a condition that can happen as a result of an HIV infection when your immune system is severely weakened.
You cant get AIDS if you arent infected with HIV. Thanks to treatment that slows down the effects of the virus, not everyone with HIV progresses to AIDS. But without treatment, almost all people living with HIV will advance to AIDS.
Insights Into How Hiv Evades Immune System
New details about how antibodies bind the human immunodeficiency virus may help bring researchers closer to creating an effective HIV vaccine.
Vaccines typically work by triggering the immune system to produce antibodies that help to beat infections. But most antibodies can’t latch onto and neutralize HIV. The proteins on the surface of the virus mutate rapidly and change shape continuously. They’re also covered with immune-evading carbohydrates called glycans.
NIH scientists recently focused on one of these HIV surface proteins, called gp120. HIV uses what are called envelope spikes, or trimers, to bind and infect cells. These spikes support three gp120 molecules, which HIV uses to grip and to gain entry into the cells it infects.
Researchers had a major breakthrough in 2007 when they identified an unchanging region of gp120 as a potential site of viral weakness. Further studies, however, found that the vast majority of antibodies that bound to this site don’t block HIV from infecting cells. Dr. Peter D. Kwong at the Vaccine Research Center of NIH’s National Institute of Allergy and Infectious Diseases headed a research team investigating how the virus resists these antibodies.
Kwong points out that people with HIV can generate antibodies to this sitein fact, that’s how it was discovered in the first place. We just haven’t yet learned how to do that by vaccination, he says, but we’re working on it.
by Harrison Wein, Ph.D.
Read Also: What Is The Most Common Mode Of Transmission Of Hiv
How Is It Treated
The standard treatment for HIV is a combination of medicines called antiretroviral therapy, or ART. Antiretroviral medicines slow the rate at which the virus multiplies.
Taking these medicines can reduce the amount of virus in your body and help you stay healthy.
Medical experts recommend that people begin treatment for HIV as soon as they know that they are infected.footnote 2, footnote 3
To monitor the HIV infection and its effect on your immune system, a doctor will regularly do two tests:
- Viral load, which shows the amount of virus in your blood.
- CD4+ cell count, which shows how well your immune system is working.
After you start treatment, it’s important to take your medicines exactly as directed by your doctor. When treatment doesn’t work, it is often because HIV has become resistant to the medicine. This can happen if you don’t take your medicines correctly.
Why Does The Immune System Fail To Fight The Hiv Virus
There are various reasons which can contribute to the failure of the immune system to control HIV infection and prevent AIDS development. By infecting CD4+ T cells, HIV is able to replicate predominantly in activated T cells and paralyse one of the main components of adaptive immune system. HIV can also establish latent infection in CD4+ T cells and remain invisible to CD8+ T cells and therefore replication can occur later in the infection and generate new virions. Antigenic mutation within the T-cell epitopes can affect the binding capacity of MHC molecules to the viral peptides, resulting in the inability of the TCRs to recognise the MHC-peptide complex. Finally, HIV is able to hide from anti-HIV antibodies by expressing non-immunogenic glycans on key antibody epitopes.
You May Like: How Does Hiv Rash Look
Initial Description And Early Spread
In the United States, HIV disease was first described in 1981 among two groups, one in San Francisco and the other in New York City. Numerous young homosexual men presented with opportunistic infections that, at the time, were typically associated with severe immune deficiency: Pneumocystis pneumonia and aggressive Kaposi sarcoma.
HIV itself was not identified for another 2 years. During that time, various other causes were considered, including lifestyle factors, chronic drug abuse, and other infectious agents. The HIV epidemic spread rapidly and silently in the absence of testing.
However, clear clinical implications arose before society became aware of the disease for example, prior to the recognition of HIV, only one case of Pneumocystis pneumonia not clearly associated with immune suppression was diagnosed in the United States between January 1976 and June 1980. In 1981 alone, 42 similar diagnoses were made, and by December 1994, 127,626 cases of Pneumocystis pneumonia with HIV infection as the only identified cause of immune suppression had been reported to the Centers for Disease Control and Prevention . Also, Kaposi sarcoma is up to 30,000 times more likely to develop in persons with HIV infection than in immunocompetent persons.
What Does Hiv Do To A Person Symptoms & Stages
Human immunodeficiency virus attacks and weakens the immune system, impairing the body’s ability to fight diseases and infections. Without a healthy, functioning immune system, a person may become vulnerable to infections that can then lead to life-threatening illnesses.
HIV targets and destroys CD4 cells, which is a type of white blood cell in the immune system that detects abnormalities and infections in other cells. HIV integrates itself into the DNA of the immune cell and tricks white blood cells into making new copies of the virus. This causes the immune cell to die, releasing the virus into the bloodstream where it goes on to infect the next cell. In this way, the virus multiplies, and the viral load builds up in the body.
In a healthy person, the CD4 count is between 500 and 1,600, but in a person infected with HIV, it can even go below 200. Weakened immunity can make a person prone to infections and other diseases, and it can be difficult to heal even from minor injuries.
If HIV infection is not treated, it can cause acquired immunodeficiency syndrome , which is the most advanced stage of HIV infection. There is currently no cure for AIDS.
Recommended Reading: What To Do When Condom Breaks To Prevent Hiv
When Do You Start Art With Hiv
Treatment with HIV drugs is recommended for anyone living with HIV. People living with HIV should start taking HIV medications as soon as possible after being diagnosed with HIV. One of the main goals of HIV treatment is to reduce a persons viral load to an undetectable level.
When should ART be started?
ART should be initiated as soon as possible after HIV diagnosis . When initiating ART, it is important to educate patients about the goals and benefits of ART and to identify and address barriers to engagement in care and adherence to treatment .
How high is a normal CD4 count?
A normal CD4 count ranges from 500 to 1200 cells/mm3 in adults and adolescents. In general, a normal CD4 count means that your immune system is not yet significantly affected by HIV infection. A low CD4 count indicates that your immune system has been affected by HIV and/or the disease is progressing.
What Else Should I Know
Treatment has improved greatly for people with HIV. By taking medicines and getting regular medical care, HIV-positive people can live long and healthy lives.
People with HIV need a medical care team for the best treatment and support.
If you or someone you know has HIV or AIDS it is important to:
- goes to all doctor visits
- takes all medicines exactly as directed
- goes for all follow-up blood tests
- understands what HIV/AIDS is and how it spreads
- is physically active, gets enough sleep, and eats well
Find more information at:
Recommended Reading: Can Hpv Lead To Hiv
How Is Hiv Diagnosed
HIV is diagnosed with either a test of your blood or your spit . You can take a test at home, in a healthcare providers office or at a location that provides testing in your community.
If your test comes back negative, no further testing is required if:
- You havent had a possible exposure in the previous three months before testing with any kind of test.
- You havent had a possible exposure within the window period for a test done with a blood draw.
If you have had a possible exposure within three months of testing, you should consider retesting to confirm the negative result.
If your test comes back positive, the lab may do follow-up tests to confirm the result.