Thursday, July 18, 2024

Chances Of Hiv After One Exposure

Oral Sex Is Least Likely To Result In Hiv Transmission

HIV : Meaning of ‘high risk exposure’ & window period – Dr Ramakrishna Prasad

The risk of transmission through oral sex is much lower than through anal or vaginal sex. This is because the oral cavity contains a thick epithelial layer, a low number of CD4 target cells, and antiviral antibodies.

A 2008 meta-analysis by Baggaley and others of 10 studies aimed at calculating the risk of HIV transmission through oral sex found that only 4 of the studies reported a non-zero estimate of risk from unprotected oral intercourse. For this reason, the CDC describes the chance of HIV transmission through oral sex as low.

How Would I Know If Prep Is Right For Me

PrEP is one of many options for preventing HIV. HIV is passed from one person to another through sharing injection drug equipment or through anal or vaginal sexual intercourse. People can avoid getting HIV by: 1) not sharing drug injection equipment , 2) avoiding anal or vaginal intercourse 3) having only one monogamous sex partner whose HIV status is known to be negative: 4) having only one partner who is living with HIV and has an undetectable viral load. It is important to be aware that a person living with HIV who is on HIV treatment and is virally suppressed for six months or longer cannot pass HIV to a partner through sex. If you have sex with more than one partner, taking PrEP or consistent and correct use of condoms each time you have sex, can prevent you from getting HIV.

New York HIV State Clinical Guidelines indicate that healthcare providers should discuss PrEP as an HIV/STD prevention option for adults or adolescents who:

It is important to weigh the pros and cons and have an open and honest conversation about PrEP with your healthcare provider before beginning PrEP. PrEP is always voluntary and only you can determine if PrEP is right for you.

Ureaplasma Transmission: More Likely In Women With Multiple Sexual Partners

Ureaplasma infection can be caused by either Ureaplasma parvum or Ureaplasma urealyticum. We know that both naturally live on and in the human body. Under some circumstances, atypical bacteria can occur and colonize the body, causing an infection.

People can acquire the atypical bacteria through vaginal and oral sexual acts, which is why they are called opportunistic pathogens.

Research by Kokkayil and Dhawanin 2015 showed that the rate of vaginal colonization of Ureaplasma is from 8.5% to 77.5%. The colonization rate was found to be associated with having multiple sexual partners, and the transmission rate per sexual act is still unknown.

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Risk Factors In Women

The HIV risk from vaginal sex without condom use is higher among women for a number of reasons. Chief among them are the ways that women’s bodies are different from men’s.

Normally, the body’s immune system recognizes and responds to an invading virus. Instead, HIV reverses its mission. The CD4 T-cells meant to help neutralize the threat are instead attacked. This means the body supports its own infection instead of fighting it.

The epithelial tissue that lines the vagina is far more susceptible to HIV than those of the penis. HIV is able to pass through these tissues.

The surface area of these vaginal tissues is far greater than that of the urethra, the thin tube that runs through the penis and connects to the bladder. For this reason, the chances of HIV infection are much higher in women.

Other vulnerabilities based on differences between men and women include:

The daily use of an HIV drug called pre-exposure prophylaxis can reduce the risk of HIV in an uninfected partner. There is evidence, however, that it works less well in women.

Research models developed from a study of 49 women in 2016 suggest the level of the active drug molecule in vaginal tissue isn’t nearly as high as when it is used in the rectal tissue of men who have sex with men.

Putting A Number On It: The Risk From An Exposure To Hiv

Who Should Get Tested?

This information was provided by CATIE . For more information, contact CATIE at 1-800-263-1638.

Author: James Wilton

Service providers working in HIV prevention are often asked by their patients and clients about the risk of HIV transmission from an exposure to HIV through sex. What do the latest studies tell us about this risk? And how should we interpret and communicate the results?

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Male Vs Female Partners

When having vaginal sex without a condom with a partner who has a penis, the vaginal membranes are more likely to tear than the partners penis.

In condomless anal sex with a partner who has a penis, the rectal membranes are also more likely to tear than the partners penis. Microscopic tears create an easier path for HIV and other STIs to enter the body when exposed.

Its possible for a partner with a penis to contract HIV during vaginal and anal sex. If a female partner is living with HIV with a detectable viral load, it can be carried in her vaginal secretions. If her partner has open sores on their mouth or penis, they can create a gateway for vaginal secretions or other bodily fluids with HIV to enter the body.

Uncircumcised men are at higher risk of contracting HIV from condomless sex than circumcised men. The delicate membranes of foreskin can tear during sex, creating a pathway for HIV to enter the body.

Mother To Child Transmission

Having HIV does not mean a woman cant have a healthy baby. The key is to work with a doctor to take all the necessary precautions.

Aside from blood and sexual secretions, HIV can also be transmitted during pregnancy or through breast milk while breastfeeding. Mother to child transmissions can also occur at any point during pregnancy, as well as during delivery.

All pregnant women should be screened for HIV. Antiretroviral therapy is strongly recommended for pregnant women with HIV to achieve viral suppression. This will subsequently reduce the risk of transmitting HIV to the baby during pregnancy and labor. Sometimes a caesarean delivery is recommended to reduce transmission during delivery if the infection is not suppressed.

Its also important to protect the baby after birth. Breastfeeding might not be recommended in some cases, though consistent viral suppression may reduce the transmission of HIV through breast milk. A doctor may also recommend that the baby take antiretroviral therapy for up to six weeks after birth.

Overall, great strides have been made in decreasing HIV transmission between mothers and infants due to improved screening and use of anti-HIV drugs during pregnancy.

In the United States, the

Globally, the figures are even more dismaying. While the sexual transmission of HIV in the U.S. is highest among gay and bisexual men , heterosexuals are by far the group most affected worldwide.

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Challenges In Calculating A Number

It isn’t easy for researchers to calculate the risk of transmission from an exposure to HIV through sex. To do this effectively, a group of HIV-negative individuals need to be followed over time and their exposures to HIVboth the number of times they are exposed and the types of exposureneed to be tracked.

As you can imagine, accurately tracking the number of times a person is exposed to HIV is very difficult. Researchers ask HIV-negative individuals enrolled in these studies to report how many times they have had sex in a given period of time, what type of sex they had, how often they used condoms and the HIV status of their partner. Because a person may have trouble remembering their sexual behaviour or may not want to tell the whole truth, this reporting is often inaccurate.

Furthermore, a person does not always know the HIV status of their partner. For this reason, researchers usually enroll HIV-negative individuals who are in stable relationships with an HIV-positive partner . Researchers can then conclude that any unprotected sex reported by a study participant counts as an exposure to HIV.

Risk Of Hiv Infection Per Single Sexual Exposure To An Individual Living With Hiv And Other Life Events With Comparable Risk Of Occurrence The Center For Hiv Law And Policy

Pre-exposure Prophylaxis (PrEP) to reduce chances of acquiring HIV

Much of the discrimination that PLWH experience from the workplace to the many criminal laws that target them is based on a gross misunderstanding of the actual routes and statistical likelihood of HIV transmission. There is a broad lack of understanding that, even without effective antiretroviral treatment that reduces the level of HIV virus in the system and consequently the risk of transmission, most sex with a person who has HIV does not result in transmission to their partner.

This chart summarizes estimates on the actual per-act risk of HIV transmission through different types of sexual contact e.g., receptive and insertive vaginal or anal sex and then lists the risk of injury through life events that have a similar risk of occurring.

We created this short document to illustrate the fact that HIV is in fact a difficult virus to transmit, and to increase understanding of actual HIV transmission risks by comparing them to life events that cause immediate harm or death and pose a similar likelihood of happening.


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No 4 Having Vaginal Sex : 1 In 1250

Most women who get HIV are infected through vaginal sex. In such cases, an HIV-positive man transmits the virus to his female partner through preseminal fluid or ejaculate, which allows HIV to pass through the linings of the vagina and cervix.

  • Reduce the risk. In theory, withdrawal practiced as a safety measure may help reduce a womans risk of contracting HIV from an HIV-positive partner, but because the virus can be found in preseminal fluids, the method may not be effective. Using condoms, however, can help lower the odds of transmitting HIV by 80 percent or more, according to the World Health Organization.

Women Are At Greater Risk Of Contracting Hiv

Researchers have found that female partners have a slightly higher risk of getting HIV.

The risk of HIV transmission through receptive vaginal sex ranges from 0.08% to 0.19%, according to a 2009 study by Boily and others and a 2012 secondary analysis of clinical trials performed by Hughes and others.

The risk to male partners was found to be slightly lower, 0.05% to 0.1%, by Fox and his colleagues.

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At What Stage Of The Infection Can Hiv Be Transmitted

If someone with HIV is taking HIV medication and has an undetectable viral load, they cannot pass on the virus. It can take up to six months on treatment to become undetectable.

Someone with HIV can pass on the virus if they have a detectable viral load.

This often happens during the first few months after infection when the levels of the virus in their body fluids are at their highest and they may not yet have been diagnosed.

This is why testing and early diagnosis are so important you can start treatment right away to protect your health and reduce your viral load to undetectable levels.

If the person with HIV has a detectable viral load, the virus is free to enter the HIV negative persons bloodstream. This can happen during vaginal and anal sex .

It can also happen when an object that has body fluids on it is put inside an HIV negative person during sex.

Risk By Sexual Activity

Core Concepts

In the U.S., vaginal sex accounts for some 5,300 new infections each year among women. There are about 2,400 new infections in men who have sex with women, although the vast majority of the 34,800 new cases occur in men who have sex with other men.

To be sure, the HIV transmission rates have improved over the years. But much of the drop in overall cases is seen in men, while progress for women remains stalled.

At the global scale, heterosexuals are by far the group most affected. For example, in African nations, vaginal sex is the most likely route of HIV infection.

When discussing HIV risk, people often look at which “type” of sex is riskier. They compare vaginal, anal, and oral sex. Based entirely on the numbers, anal sex is considered the highest risk activity. The risk of HIV infection is almost 18 times greater with anal sex than it is for vaginal sex.

Statistics are not individual people. It’s true that vaginal sex may pose an overall lower risk when compared with anal sex. What the data can’t tell you is how the risk of HIV infection may differ among men and women who practice vaginal sex.

The data on risk doesn’t always explain factors that make some people more vulnerable. It doesn’t consider how these factors cause HIV infection risk to be much higher than it is for other people.

Some men are far more likely to get HIV than other men are. Studies suggest uncircumcised men are more than twice as likely to get HIV after vaginal sex than circumcised men.

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How Hiv Treatment Stops Hiv Being Passed On

  • A person with HIV who is taking treatment and has an undetectable viral load cannot pass on HIV.
  • Pre-exposure prophylaxis is a course of HIV drugs taken by an HIV negative person to lower the chance of infection. When taken correctly, PrEP significantly reduces the chances of becoming HIV positive.
  • Post-exposure prophylaxis is a month-long course of HIV medication taken by an HIV negative person after possible exposure to reduce the chance of getting HIV. When started in time, PEP can stop HIV infection after sex without a condom with someone who has a detectable viral load but it doesnt work every time.

I Have Sex Partners Who Are Living With Hiv And Have An Undetectable Viral Load Because They Are On Hiv Treatment Do I Still Need To Take Prep

Individuals living with HIV who are taking HIV treatment consistently and have an undetectable viral load for at least 6 months cannot transmit the virus to an HIV-negative partner through sexual activity. In sero-discordant or magnetic couples , PrEP may be used by the HIV-negative partner for additional protection.

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No 6 Having Oral Sex: Negligible

The odds of contracting HIV during oral sex are slim to none. Thats because the virus isnt transmitted through saliva, tears, or sweat unless its also mixed with blood. If an HIV-positive man ejaculates in his partners mouth, however and, for example, the partner has an open sore or bleeding gums experts say that it might theoretically be possible to pass along the virus.

  • Reduce the risk. Using a condom or dental dam can help lower the risk of transmitting not only HIV but other STDs, including syphilis, herpes, gonorrhea, and chlamydia. People can also reduce their risk by having their HIV-positive partner ejaculate into a condom or by removing their mouth from the penis before ejaculation.

Interpreting The Numberswhat Additional Information Needs To Be Provided

HIV Basics: Testing, Prevention, and Living with HIV

Some clients may see these numbers and think their risk of HIV transmission is low. Therefore, caution is needed when interpreting them. If these numbers are provided to clients, they should be accompanied by information that helps shed light on why the risk may be higher than it seems.

Transmission can occur after one exposure.

It is important to emphasize that a person could become infected from having unprotected sex once or a person could have unprotected sex many times and not become infected, regardless of how low or high the risk per exposure is.

A risk of 1% would mean that an average of one infection would occur if 100 HIV-negative people were exposed to HIV through a certain type of sex. It does not mean that a person needs to be exposed 100 times for HIV infection to occur.

These are estimates of average risk in the absence of biological factors that increase risk.

The numbers in the table above are rough estimates. They are averages and do not represent the risk from all exposures to HIV through a certain type of sex.

The risk of HIV transmission may be much higher than these averages if biological risk factors are present. For example, research shows that STIs and some vaginal conditions, such as bacterial vaginosis, can increase the risk of HIV transmission by up to 8 times.6,7,8 As a result, the risk of an HIV-negative woman becoming infected through unprotected receptive vaginal sex could be closer to 1% if she has a vaginal STI.

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Hiv Treatment As Prevention

People with HIV can take ART to lower their chance of transmitting HIV to others.

ART reduces the quantity of HIV in the body, or viral load, and keeps it at a low level.

The term viral load refers to the number of HIV copies per milliliter of blood.

Healthcare professionals define successful viral suppression as having a viral load of less than of HIV per milliliter of blood. Achieving and maintaining viral suppression significantly reduces the risk of HIV transmission.

Other ways to prevent HIV transmission include:

  • using a condom or other barrier method during sex
  • reducing the number of sexual partners
  • getting vaccinated against other STIs, such as HPV and hepatitis B
  • avoiding using injectable drugs, if possible
  • if using injectable drugs, avoiding sharing needles and syringes
  • following all workplace safety protocols

People can speak with a doctor to learn more about their individual risk of contracting HIV.

Anyone concerned about HIV exposure should contact a healthcare professional or a local emergency room to get testedand receive PEP.

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