There is life with HIV

Antiretroviral Therapy Viral Load And Contagion

Are the risks taken based on the undetectable likewise the non-transferable, really, liberating? I do not know...

Antiretroviral Therapy and HIV Contagion. Yes, ART can prevent contagion, but condoms have always been effective in my life and I recommend condoms…

Antiretroviral Therapy, ART, has changed the face of the HIV / AIDS pandemic, as it reduces viral load and reduces the chances of a drop in CD4 count; better than that, it allows the immune system to rebuild itself, at least partially! So things were presented to me. In those days, in those gray years, nobody thought of ART as something to be used to avoid contagion!

Was what we were taught the following?

If you are HIV positive and start having sex (choose your euphemism) with another person living with HIV, you YOU MUST CONTINUE using a condom, as there is a risk of reinfection and, mind you, you may be contaminated with a strain resistant to your therapy! Or, even, resistance to most medications, taking into account cross resistance.

And this text seeks to show that, as well as other things. Keep reading ...

… Antiretroviral Therapy, Viral Load And Contagion 

It is now well known that the use of HIV treatment, antiretroviral therapy, not only improves the health of people living with HIV, but, they say, it is also a highly effective strategy for preventing HIV transmission.

This is because HIV treatment can reduce the amount of viruses (viral load) in the blood and other body fluids (such as semen and vaginal and rectal fluids) to undetectable levels. 

To become and remain undetectable, people living with HIV need to take anti-HIV treatment as prescribed. In addition to taking HIV medications, regular visits to the doctor are important to monitor viral load to ensure that it remains undetectable and to receive other medical support.

Evidence shows that people living with HIV undergoing treatment, taking care of their health and keeping their viral loads undetectable have such characteristics:

  • may not transmit HIV to their sexual partners;
  • do not transmit HIV to the baby during pregnancy and childbirth (if an undetectable viral load is maintained during pregnancy and childbirth);
  • have a chance very reduced transmitting HIV through breastfeeding; however, breastfeeding is not recommended for HIV-positive mothers in Canada - the origin of this text, my reader, is Canadian - and feeding with exclusive formula is the current recommendation;
  • Probably have a very low chance of transmitting HIV to people with whom they share injecting drug equipment; however, there is insufficient evidence to conclude that there is no risk. 
  • And it is recommended that people use new needles and other equipment whenever they use drugs, regardless of their HIV status or viral load, to prevent HIV and other ills.

How does HIV treatment and an undetectable viral load work to prevent HIV transmission?

HIV treatment, also called antiretroviral therapy, or ART, works by controlling the replication of HIV in the body - that is, it reduces the ability of HIV to make copies of itself (replication).

When HIV replication is controlled, antibodies can destroy copies of HIV circulating in blood and body fluids, so according to research, as the viral load falls, it also decreases the risk of HIV transmission. When successful treatment reduces viral load to undetectable levels, it can significantly reduce or eliminate the risk of HIV transmission.

Antiretroviral Therapy, ART, usually consists of a combination of three antiretroviral drugs taken daily. Depending on medical prescriptions that are guided by research results. New treatments for HIV are safer, simpler and more effective than when antiretroviral therapy was introduced in 1996/1997.

The power of ART today is so profound that many people who start effective treatment soon after becoming HIV-positive will have an life expectancy almost normal.

For most people, the virus becomes so well controlled that, three to six months after starting treatment, the amount of virus in the blood becomes undetectable by the tests used routinely. Most viral load tests used in Canada cannot detect HIV in the blood if there are less than 40 to 50 copies of the virus per ml. However, the virus is still present in very low amounts in the body when the viral load is undetectable.

What is involved in the consistent and correct use of ART and an undetectable viral load for HIV prevention?

Consistent and correct use of ART to maintain an undetectable viral load includes:

  • high adherence to ART drugs, to achieve and maintain an undetectable viral load Consultations
  • regular medical visits to monitor viral load and receive support for adherence, if necessary

Regular testing and treatment for sexually transmitted infections (STIs) are also important, as this strategy does not protect against STIs; therefore, I, Cláudio, wonder if the good idea is not the continued spread of condom use as an efficient way to prevent the spread of STD, which includes HIV infection and, it is always good to remember, zyka, a virus quite wicked!

I must be very annoying, in the opinion of the people of the huh-huh-huh-huh right?

A person on ART needs to work with their doctor to determine an appropriate schedule for medical check-ups and viral load monitoring.

What is important for this approach to work?

After starting treatment, the viral load must become and remain undetectable for this approach to provide protection.

When a person starts treatment, it usually takes three to six months for the viral load to become undetectable. Most people will end up having a Undetectable viral load if you have a combination of drugs that is effective against your HIV strain and take it as prescribed by your doctor.

Viral load must remain undetectable for at least six months before relying on this approach as an effective HIV prevention strategy. 

A person must continue to have high adherence to treatment to maintain an undetectable viral load over time. The only way to know if your viral load remains undetectable in the long run is to do regular viral load tests while doing, with draconian discipline.

However, not all viral load becomes and remains undetectable during treatment. This occurs most commonly when someone has low adherence to medications, but it can also occur due to drug resistance. When treatment fails, the person will not know that their viral load is detectable until they have another viral load test. Depending on the reason for treatment failure, a person may require a change in treatment or may benefit from adherence counseling to reduce their viral load to undetectable levels. The best options for moving forward should be discussed with a doctor.

To what extent does the use of ART to maintain an undetectable viral load prevent sexual transmission of HIV?

Research on serodiscordant couples (where one partner is HIV positive and the other partner is HIV negative) shows that, when used consistently and correctly, the use of ART to maintain an undetectable viral load is a highly effective strategy to prevent transmission HIV for heterosexual and same-sex couples. Evidence from this research shows that when people are successfully receiving ART and providing care, they do not transmit HIV through sexual intercourse.

The first study to show that ART and an undetectable viral load have a great benefit in preventing heterosexual serodiscordant couples was the randomized clinical trial known as HPTN 052. In the final analysis, which included 1.763 heterosexual serodiscordant couples (half of whom were followed up by more than five and a half years), no HIV transmission occurred between couples in the study when the HIV-positive partner was on ART and had an undetectable viral load (defined as <400 copies / ml in this study).

In total, there were eight transmissions between couples while the HIV-positive partner was on ART; however, in all eight cases, viral load was detectable, despite being on ART.

Four transmissions occurred in the first three months after the HIV-positive partner started treatment, before the viral load was undetectable.

The other four came when the treatment failed to keep the viral load at undetectable levels.

In addition to these eight transmissions, there were 26 people who acquired HIV infection from a sexual partner outside their primary relationship, showing that in a serodiscordant couple in which the HIV-positive partner is on ART with undetectable viral load, the main risk of HIV transmission is HIV comes from outside the relationship.

Is Condomless Sex Safe Sex?

The results of a large observational two-phase study known as PARTNER / PARTNER2 showed that ART and an undetectable viral load (defined as <200 copies / ml in this study) prevent sexual transmission of HIV in heterosexual and same-sex couples in a absence of other forms of HIV prevention (condoms, PrEP or PEP). The first phase of the study included heterosexual and same-sex couples, and the second phase continued only with same-sex couples.

In this study, there were a large number of unprotected sex acts (without condoms) when the viral load was undetectable - approximately 36.000 among heterosexual couples and 76.000 among male same-sex couples included in the study. At the end of the study, there was no HIV transmission among couples in the study when the HIV-positive partner was on ART and had an undetectable viral load. However, there were 16 new HIV infections (15 gay men and one heterosexual person) that were transmitted a sexual partner out of the relationship. Just a fool, or a fool, to place certain bets, like Amarilis's!

An observational study similar to PARTNER, called Opposites Attract, also found no HIV transmission between serodiscordant couples of the same sex when the partner was under treatment and maintained an undetectable viral load (<200 copies / ml), despite approximately 16.800 acts of anal sex without a condom. In this study, three of the seronegative partners contracted HIV from an out-of-relationship partner.

A Little More About Partner Studies and Opposites Attract

In the PARTNER / PARTNER2 and Opposites Attract studies, an undetectable viral load was defined as less than 200 copies / ml. This is higher than the level of undetectable viral load defined by tests commonly used in Canada (less than 40 or 50 copies / ml). There was no transmission in both studies when the viral load was less than 200 copies / ml (however, the vast majority of participants did in fact have a viral load less than 50 copies / ml).

The studies used a higher cutoff point to ensure the accuracy of the viral load results and to allow comparison between the various surveys. In addition, a higher cut can capture small “viral load blips, a temporary increase in viral load above 50 copies per ml at a peak viral load that returns undetectable in a few moments.

This is important because it helps to determine whether viral load blips create a risk of HIV transmission. The results of these studies show that if a person has a blip, it does not increase the risk of HIV transmission.

However, the goal for optimal treatment results for an individual living with HIV in Canada is a viral load of less than 50 copies / ml, because when the viral load is low, but remains above 50 copies / ml, this creates a risk of drug resistance and viral rebound that can lead to treatment failure.

In the PARTNER / PARTNER2 and Opposites Attract studies, there was a high incidence of STIs in the participants (about 25%). Between the two studies, no HIV transmission occurred when the HIV-positive or HIV-negative partner had an STD. In PARTNER / PARTNER2 alone, there were 6.090 cases of sex without a condom when an STD was present. This indicates that an undetectable viral load prevents the transmission of HIV, even in the presence of other STDs.

All participants in these studies participated in regular health consultations to check their viral load, take an STD test and receive adherence and prevention counseling. They were also treated for STDs when needed. Such comprehensive support is an important part of regular follow-up care during ART.

The results of these (and earlier) studies provide a strong body of evidence showing that people living with HIV, who adhere to ART and receive regular health care, with a sustained undetectable viral load, do not transmit HIV sexually. PARTNER and Opposites Attract studies show that this is true even when condoms are not used and in the presence of other STIs.

To what extent does using ART to maintain an undetectable viral load prevent transmission of HIV to a baby during pregnancy and childbirth?

Without treatment, the chances of having a HIV-positive baby rise to between 15% and 30% when they are born to a person living with HIV.

However, treatment for HIV is the most effective way to reduce transmission to the baby. In fact, research has shown that if a pregnant person starts HIV treatment before pregnancy and maintains an undetectable viral load during pregnancy and childbirth, they do not transmit HIV to the baby. A short course of HIV medication is also given to the baby to prevent HIV transmission.

One of the main studies that showed the impact of treatment on preventing HIV transmission to a newborn was a French cohort study conducted between 2000 and 2011. 

This study found that no HIV transmission occurred among 2.651 babies born to cis gender women who were undergoing treatment before conception and during pregnancy and who had an undetectable viral load at delivery. 

However, if treatment is not carried out throughout pregnancy or if an undetectable viral load is not maintained, there is still a risk of HIV transmission to the baby during pregnancy and / or delivery.

HIV testing is important for people who are pregnant or who are considering becoming pregnant. People with a positive test should start HIV treatment as soon as possible to reduce or eliminate the risk of HIV transmission to their babies. Likewise, people living with HIV who wish to become pregnant should consult an HIV specialist as soon as possible, preferably before conception, to determine an appropriate treatment regimen for pregnancy.

How well does using ART to maintain an undetectable viral load prevent transmission of HIV to a baby while breastfeeding?

The risk of HIV transmission through breastfeeding during the treatment and maintenance of an undetectable viral load is very low, but not equal to zero. 

A systematic review of HIV transmission in breastfed babies of cisgender women undergoing treatment found that the risk of transmission after birth was 1% after six months of breastfeeding, increasing to almost 3% after one yearo. 

However, in these studies, women remained on treatment for varying periods of time and did not continue treatment beyond six months after delivery. The systematic review did not consider adherence to ART and viral load, which means that we do not know how many women had detectable viral load at the time of transmission, despite undergoing anti-HIV treatment. 

There is very limited research on the impact of treatment and an undetectable viral load on HIV transmission during breastfeeding. A study in Tanzania between 2013 and 2016 found two HIV transmissions among 177 babies who were breastfed by cisgender women who started treatment before the baby was born. However, in both cases, women had a detectable viral load. No transmission occurred in the context of treatment with good adherence and undetectable viral load.

The PROMISE study, conducted in Africa and India, provided treatment for 2.431 lactating cisgender women or their newborn babies. Among the 1.219 cisgender women who received treatment, seven babies contracted HIV at 12 months (an HIV contagion rate of 0,57%). 

AOnly two of these cases occurred in women with an undetectable viral load. Another study found two cases of HIV transmission among breastfeeding women, who appeared to have an undetectable viral load at the time of transmission. However, in all of the above cases, low adherence to treatment is suspected.


Canadian guidelines continue to recommend that HIV-positive parents feed their babies exclusively with formula to eliminate the possibility of transmission. Here in Brazil, I cannot fail to call the attention of Renata Cholbi's notable and successful efforts, whose trajectory I was able to follow, in silence, while following my own path in the cause. The lives that Cholbi saved, improved, prolonged were, and there are so many that I cannot, I could not fail to pay him this tribute here:

Renata Cholbi. Tanto nomini nullum por Praise ', that is, “So great a name no praise reaches it

However, due to the evidence showing minimal risk and the support available in resource-rich countries like Canada, there is a growing movement to support people with HIV who wish to breastfeed and to help them do so in the safest way possible . 

This includes: providing unbiased information on the risk of HIV transmission through breastfeeding; provide increased viral load monitoring and adherence support; and providing prophylactic treatment for babies born to people living with HIV.

To what extent does the use of ART to maintain an undetectable viral load prevent the transmission of HIV through the use of injectable drugs?

The limited research available suggests that being on ART and maintaining an undetectable viral load is effective in helping to prevent HIV transmission among people who inject drugs; however, there is insufficient evidence to conclude that there is no risk. People who inject drugs should be encouraged and supported to use new needles and other equipment every time they use drugs to prevent HIV and other ills.

The three main studies that analyze sexual transmission of HIV (HPTN 052, PARTNER and Opposites Attract) did not systematically recruit people who inject drugs in studies, did not ask if participants were sharing injection equipment and did not provide any analysis related to participants who reported drug use.

Two ecological studies from Vancouver and Baltimore reported reductions in new HIV infections over time and found an association with a reduction in the community viral load of people who inject drugs. 

Although it is likely that the increase in ART uptake is partly responsible for the observed decline in the number of new infections, it is difficult to know how much of this change can be attributed to an increase in harm reduction services that also occurred during this period. 

A cohort study in India of 14.481 people who inject drugs and 12.022 men who have sex with men found a clear correlation between the estimated HIV incidence and treatment coverage at the community level and viral suppression. This study found significant correlations at the community level, but since it was not designed to examine individual risk of transmission, no estimate of effectiveness was available.

Should using ART to maintain an undetectable viral load be used as a substitute for condoms and other HIV prevention strategies?

While using ART to maintain an undetectable viral load works regardless of whether you use condoms or PrEP, everyone should be able to choose a prevention strategy that works best for them. This strategy is one of several highly effective options for preventing sexual transmission of HIV; however, it does not offer protection against STDs (such as herpes, chlamydia, gonorrhea or syphilis). Condoms are the only effective strategy to help prevent STDs.

And it has been, I must add, the most present strategy over the years that has had the properties of reducing the number of people contaminated, and possibly killed, with such expressiveness that makes me think, and to say that PrEP and TasP reach the verge of folly , considering the volume of economic resources involved.


For people who use injecting drugs, other prevention programs and strategies (such as the distribution and use of new injection equipment) are important for transmission to help prevent HIV, and to prevent other blood-borne infections, such as hepatitis Ç. 

Especially this importance, lives saved daily, I fear that, in this moment of political, social, cultural and humanistic obscurantism, it is not impossible, and I have to be “giving ideas”, that the harm reduction programs are interrupted, paralyzed or even destroyed in the name of the vaccine control of COVID-19, which is necessary, urgent and very important, while there are no better prices for needles and syringes. When there was the eagerness and lust for the acquisition of chloroquine, prices were not “deterrent forces”.

Bozo's colinha, however ...

My final remarks:

Yes! It is "scientifically proven" that viral load and contagion are related. But it remains very well proven, in practical life, that the use of condoms, in itself, causes less problems and avoids, with 100% effectiveness, contagion, regardless of viral load.

Viral load and contagion are related and, however, if you allow me to ingest in your life, always consider, always, always and always, the use of condoms, condoms, because you can never be sure of having your undetectable viral load at the time of sex and, if she is not undetectable at that moment, that day, the condom “will do the job”, it will make a difference.

I know what it meant to not use a condom in my life. And I know what it still represents and I can already foresee what it will still represent.


If at least…

Further reading
  1. HIV Infection: Medication Against HIV Prevents HIV Infection
  2. Viral Rebound and Chemical Dependence
  3. Undetectable Viral Load Gives Negative Test?
  4. Undetectable Viral Load and HIV-negative transmission
  5. Undetectable Viral Load gives No Reagent?
  6. CD4 Know What It Is And Understand Why Blood Count Does Not Assess Immunity!
  7. PrEP and Sorodiscordant Couples
  8. Risk of getting HIV! What Are Your Risks In These Scenarios?
  9. HIV Infection Signs and Symptoms - Linking to Rash
  10. Viral charge! What is it, and what are viral load tests for?


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  3. Eshleman SH, Hudelson SE, Redd AD, et al. Treatment as prevention: Characterization of partner infections in the HIV Prevention Trials Network 052. Journal of Acquired Immune Deficiency Syndromes. January 1, 2017; 74 (1): 112–116.
  4. Rodger AJ, Cambiano V, Bruun T, et al. Condomless sexual activity and risk of HIV transmission in HIV-positive couples when the HIV-positive partner is using suppressive antiretroviral therapy. Journal of the American Medical Association. 2016; 316 (2): 171–181. Available in:
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Author (s): Arkell C.

Published: 2020


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