What Happens At The Binding And Fusion Stage
HIV attaches to a T-helper cell. It then fuses to it and releases its genetic information into the cell.
The types of ARVs that stop this stage of the lifecycle are called fusion or entry inhibitor drugs. They stop HIV from entering the cell. Your healthcare provider will let you know if these are the right ARVs for you.
Why Do Some People Say Hiv Started In The Usa In The 1980s
Because this is when people first became aware of HIV, and it was when HIV was officially recognised as a new health condition. But HIV had actually been around for decades by then.
In 1981, rare diseases, such as Kaposi’s Sarcoma and a lung infection called PCP, were being reported among gay men in New York and California. Scientists began to suspect that an unidentified infectious ‘disease’ was the cause.
At first, the âdiseaseâ was called all sorts of names relating to the word âgay’. It wasn’t until mid-1982 that scientists realised it was also spreading among other populations, such as haemophiliacs and people who inject drugs. In September that year, they named it Acquired Immune Deficiency Syndrome .
In 1983, scientists at the Pasteur Institute in France identified the virus linked to AIDS, which they called Lymphadenopathy-Associated Virus . Scientists at the USA National Cancer Institute confirmed this virus was the cause of AIDS and called it HTLV-III. LAV and HTLV-III were later acknowledged to be the same. A few years later, the virus was renamed as HIV.
Pretreatment Hiv Drug Resistance
Drug resistance can be found in some people before they begin treatment. This resistance can either be transmitted at the time of infection or acquired during previous treatments, for example in women given antiretroviral medicine to prevent mother-to-child transmission of HIV.
WHO recommends surveillance of HIV drug resistance in adults initiating or reinitiating ART and in treatment naive infants initiating ART to inform optimal selection of first-line regimens.
Up to 10% of adults starting HIV treatment can have drug resistance to the NNRTI drug class. Pretreatment NNRTI resistance is up to 3 times more common in people with previous exposure to antiretroviral drugs. The prevalence of drug-resistant HIV is high in children under 18 months of age and newly diagnosed with HIV. Based on surveys conducted in 10 countries in sub-Saharan Africa , nearly one half of infants newly diagnosed with HIV have NNRTI resistant virus before initiating treatment.
The global prevalence of NNRTI resistance in adults and infants emphasizes the need to fast-track the transition to WHO-recommended dolutegravir-based treatments.
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Emergency Hiv Pills: Pep
72 hours should speak with a healthcare professional about post-exposure prophylaxis . PEP may be able to stop the infection, especially if a person takes it as soon as possible after the potential exposure.
A person takes PEP for 28 days, and a doctor monitors them for HIV afterward. PEP is not 100% effective, so it is important to use prevention techniques, such as barrier protection and safe injection practices, including while taking PEP.
What Are Hiv And Aids
The human immunodeficiency virus is a virus that affects the immune system. It gradually destroys cells called CD4 cells, which usually help the body stay healthy by fighting off disease.
If HIV is not treated, most people will develop severe immune deficiency within 10 years. At this point, the body is no longer able to fight infection and stop cancer from developing. This late stage of HIV infection is called acquired immunodeficiency syndrome .
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How Is Hiv/aids Diagnosed
Early HIV infection often causes no symptoms, and must be detected by testing a persons blood for the presence of antibodiesdisease-fighting proteinsagainst HIV. These HIV antibodies generally do not reach levels high enough to detect by standard blood tests until 1 to 3 months following infection, and may take as long as 6 months. People exposed to HIV should be tested for HIV infection as soon as they think they may have been exposed to HIV.
When a person is highly likely to be infected with HIV and yet antibody tests are negative, a test for the presence of HIV itself in the blood is used. Repeat antibody testing at a later date, when antibodies to HIV are more likely to have developed, is often recommended.
Is There Only One Type Of Hiv
No, there are actually two types of HIV: HIV-1 and HIV-2, and they have slightly different origins.
HIV-1 is closely related to the strain of SIV found in chimps. While HIV-2 is closely related to the strain of SIV found in sooty mangabeys monkeys. The crossover of HIV-2 to humans is believed to have happened in a similar way as HIV-1 .
HIV-2 is far more rare, and less infectious than HIV-1, so it infects far fewer people. It is mainly found in a few West African countries, such as Mali, Mauritania, Nigeria and Sierra Leone.
To complicate things further, HIV is also classified by four main groups of viral strain , each of which has different genetic make-up. HIV-1 Group M is the strain that has caused the majority of HIV infections in the world today, meaning it is the dominant strain.
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Strategies For Preventing The Transmission Of Hiv
Condoms made of latex provide good protection against HIV , but they are not foolproof. Oil-based lubricants should not be used because they may dissolve latex, reducing the condom’s effectiveness.
Other measures can help. For men, circumcision, an inexpensive, safe procedure, reduces the risk of becoming infected during vaginal intercourse with an infected woman by about half. Whether circumcision reduces the risk of HIV infection in other circumstances is unclear. Because circumcision provides only partial protection against HIV infection, people should also use other measures to prevent HIV infection. For example, if either partner has a sexually transmitted infection or HIV infection, it should be treated, and condoms should be used correctly and consistently.
Innate Immune Response To Hiv
Innate immune cells are the first line of defence which HIV encounters upon entry to the body.
Macrophages. Tissue macrophages are one of the target cells for HIV. These macrophages harbour the virus and are known to be the source of viral proteins. However, the infected macrophages are shown to lose their ability to ingest and kill foreign microbes and present antigen to T cells. This could have a major contribution in overall immune dysfunction caused by HIV infection.
Dendritic cells . DCs are large cells with dendritic cytoplasmic extensions. These cells present processed antigens to T lymphocytes in lymph nodes. Epidermal DCs, expressing CD1a and Birbeck granules, are probably among the first immune cells to combat HIV at the mucosal surfaces. These cells transport HIV from the site of infection to lymphoid tissue. The follicular DCs, found in lymphoid tissue, are also key antigen-presenting cells that trap and present antigens on their cell surfaces. In the lymph node follicles, DCs provide signals for the activation of B lymphocytes.
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What Are The Effects Of Aids
A weakened immune system increases the risk of developing other conditions. These include:
- transmission from mother to baby during pregnancy, childbirth or breastfeeding
- oral sex, although this is rare
- healthcare workers receiving ‘needlestick injuries’
It is important to remember that HIV is not spread through activities such as kissing, sharing cups and cutlery, normal social contact, toilet seats or mosquitoes.
You are at higher risk of HIV infection if:
- you are a man, a transgender woman or a person who identifies as gender diverse who has sex with men
- you have sex or share needles with someone else at risk of HIV
- you share sex toys
- you have sex with people from countries with a high rate of HIV infection
- you inject illegal drugs and share needles
- you have had tattoos or other piercings overseas using unsterile equipment
- you have a sexually transmitted infection . People can be infected with several different STIs at the same time. Having an STI can make it easier to become infected with HIV and pass it on to sexual partners.
- you have had a blood transfusion in a country where the blood supply is not safe
Some people are at a higher risk of HIV infection because they are exposed to more people with HIV infection or engage in more high-risk behaviour. These include:
Stages Of Hiv Infection
The stages of infection from person to person vary slightly, both in severity and the speed of progression. These stages map the depletion of immune cells as the bodys defenses further and further degrade.
With each progression, the risk of opportunistic infections increases until the immune system is said to be fully compromised. It is at this stage that the risk of illness and death is particularly high.
The stages of infection can be roughly classified as follows:
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Using Barrier Protection And Prep
Using condoms or other barrier protection, such as dental dams, when engaging in anal, vaginal, or oral sex can drastically reduce a persons chances of contracting HIV and other STIs.
In their 2019 guidelines, the Preventive Services Task Force advises that doctors only approve PrEP for people with recent negative HIV tests.
They also approve a PrEP formation: a combination of tenofovir disoproxil fumarate and emtricitabine. They advise people who take PrEP to do so once a day.
Make Healthy Lifestyle Choices
- Eat a healthy, balanced diet to keep your immune system strong. Heart-healthy eating can help prevent some of the problems, such as high cholesterol, that can be caused by treatment for HIV.
- Learn how to deal with the weight loss that HIV infection can cause.
- Learn how to handle food properly to avoid getting food poisoning. For more information, see the topic Food Poisoning and Safe Food Handling.
- Exercise regularly to reduce stress and improve the quality of your life. Take steps to help prevent HIV-related fatigue.
- Don’t smoke. People with HIV are more likely to have a heart attack or get lung cancer.footnote 23, footnote 24 Cigarette smoking can raise these risks even more.
- Don’t use illegal drugs. And limit your use of alcohol.
Where Does Hiv Come From
HIV is thought to have occurred after people ate chimps that were carrying theâ¯Simian Immunodeficiency Virus .
HIV is a type of lentivirus, which means it attacks the immune system. SIV attacks the immune systems of monkeys and apes in a very similar way. This suggests HIV and SIV are closely related, and that SIV in monkeys and apes crossed over to humans to become HIV.
Whats The Hiv Window Period
As soon as someone contracts HIV, it starts to reproduce in their body. The persons immune system reacts to the antigens by producing antibodies .
The time between exposure to HIV and when it becomes detectable in the blood is called the HIV window period. Most people develop detectable HIV antibodies within 23 to 90 days after transmission.
If a person takes an HIV test during the window period, its likely theyll receive a negative result. However, they can still transmit the virus to others during this time.
If someone thinks they may have been exposed to HIV but tested negative during this time, they should repeat the test in a few months to confirm . And during that time, they need to use condoms or other barrier methods to prevent possibly spreading HIV.
Someone who tests negative during the window might benefit from post-exposure prophylaxis . This is medication taken after an exposure to prevent getting HIV.
PEP needs to be taken as soon as possible after the exposure it should be taken no later than 72 hours after exposure but ideally before then.
Another way to prevent getting HIV is pre-exposure prophylaxis . A combination of HIV drugs taken before potential exposure to HIV, PrEP can lower the risk of contracting or transmitting HIV when taken consistently.
Timing is important when testing for HIV.
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How Does Hiv Spread
HIV spreads when infected blood, semen or vaginal fluids enter the body. Because symptoms can be mild at first, people with HIV might not know they’re infected. They can spread HIV to others without knowing it.
HIV can spread:
- during sex
- through sharing needles for injecting drugs or tattooing
HIV also can pass from mother to child during pregnancy, childbirth, or breastfeeding.
HIV does not spread through:
- pee, poop, spit, throw-up, or sweat
- coughing or sneezing
- sharing eating utensils or drinking glasses
Case Definition For Epidemiological Surveillance
According to a study published in the Proceedings of the National Academy of Sciences in 2008, a team led by Robert Shafer at Stanford University School of Medicine discovered that the gray mouse lemur has an endogenouslentivirus in its genetic makeup. This suggests that lentiviruses have existed for at least 14 million years, much longer than the currently known existence of HIV. In addition, the time frame falls in the period when Madagascar was still connected to what is now the African continent the said lemurs later developed immunity to the virus strain and survived an era when the lentivirus was widespread among other mammals. The study was hailed as crucial, as it fills the blanks in the origin of the virus, as well as in its evolution, and could be important in the development of new antiviral drugs.
In 2010, researchers reported that SIV had infected monkeys in Bioko for at least 32,000 years. Previous to this time, it was thought that SIV infection in monkeys had happened over the past few hundred years. Scientists estimated that it would take a similar amount of time before humans adapted naturally to HIV infection in the way monkeys in Africa have adapted to SIV and not suffer any harm from the infection.
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Things To Know About Hiv Suppression
A vial of blood
A vial of blood
Development of antiretroviral drugs to treat HIV has turned what was once an almost always fatal infection into a manageable chronic condition. Daily antiretroviral therapy can reduce the amount of HIV in the blood to levels that are undetectable with standard tests. Staying on treatment is crucial to keep the virus suppressed. NIAID-supported research has demonstrated that achieving and maintaining a durably undetectable viral load not only preserves the health of the person living with HIV, but also prevents sexual transmission of the virus to an HIV-negative partner.
Having A Medication Routine
Taking HIV medication as prescribed is essential missing even a few doses might jeopardize the treatment.
A person should design a daily medication-taking routine that fits their treatment plan and schedule.
Sometimes, side effects keep people from sticking with their treatment plans. If any side effect is hard to manage, contact a healthcare professional. They can recommend a more easily tolerated drug and suggest other changes to the treatment plan.
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Is There A Vaccine For Hiv
Currently, there are no vaccines to prevent or treat HIV. Research and testing on experimental vaccines are ongoing, but none are close to being approved for general use.
HIV is a complicated virus. It mutates rapidly and is often able to fend off immune system responses. Only a small number of people who have HIV develop broadly neutralizing antibodies, the kind of antibodies that can respond to a range of HIV strains.
The first HIV vaccine efficacy study in 7 years was underway in South Africa in 2016. The experimental vaccine is an updated version of one used in a 2009 trial that took place in Thailand.
A 3.5-year follow-up after vaccination showed the vaccine was 31.2 percent effective in preventing HIV transmission.
The study involves 5,400 men and women from South Africa. In 2016 in South Africa, about contracted HIV. The results of the study are expected in 2021.
Other late-stage, multinational vaccine clinical trials are also currently underway.
Other research into an HIV vaccine is also ongoing.
While theres still no vaccine to prevent HIV, people with HIV can benefit from other vaccines to prevent HIV-related illnesses. Here are the CDC recommendations:
What Can I Expect If I Have Hiv
If youre diagnosed with HIV, its important to know that those living with HIV who follow treatment guidelines can live full lives for nearly as long as those without HIV.
If you have a high CD4 count and an undetectable viral load within a year of starting treatment, research suggests youll have the best outcomes, as long as you continue your treatment plan.
You can improve your outlook by:
- Getting tested as part of routine healthcare or if you think youve been exposed.
- Starting ART soon after being diagnosed.
- Taking your medicine every day.
- Keeping your appointments with your healthcare team.
ART can keep blood levels undetectable but cant entirely rid your body of the virus . If you dont take your medication every day, the virus can start multiplying again and mutate, which may cause your medications to stop working.
Left untreated, it can take about 10 years for HIV to advance to AIDS. If you progress to AIDS and it goes untreated, you can expect to live about three years more.
For those on treatment, if you have a high CD4 count and undetectable viral load within a year of starting treatment, you can expect to live about as long as someone without HIV. If you have a low CD4 count or a detectable viral load within a year of starting treatment, you may live 10 to 20 years less than someone without HIV.
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