Can HIV change human behaviour?

HIV has been wreaking havoc on humanity for decades, but some of its effects on the body are still being studied. This is the case of the behavior modification that this virus can cause, according to some studies..

In this article we will explore this question to discover what type of behaviors it refers to, under what conditions this effect occurs and other important characteristics.

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Can HIV change human behaviour?

Although the human immunodeficiency virus was discovered in the early 1980s, and enormous amounts of studies have been carried out on it, the truth is that in some matters it is still relatively a stranger. One of the questions that researchers are still trying to unravel is whether HIV can change human behavior.

Before delving into this issue, we must take a short tour of the implications of this virus to be able to situate ourselves. HIV seems to come from another virus, SIVcpz, which attacked some species of apes, such as chimpanzees.

Somehow, this virus made the leap to the human species, giving rise to HIV, a relentless agent against man..

HIV is transmitted mainly through fluids, so the sexual route quickly became the main source of infection, before that enough was known to take action in this regard and prevent the very rapid progression that this epidemic experienced in the 1980s.

Before going on to study whether HIV can modify human behavior, it is important to know that the main problem with this virus is that, in the long term, it generally 10 years thanks to the pharmacological advances that have been made in this regard, it can cause the so-called acquired immunodeficiency syndrome in the host, or AIDS.

Once this disease develops, the subject who suffers from it sees how his immune system progressively deteriorates until becoming extremely more prone to infections or other diseases, such as cancer. Under such conditions, this person's life expectancy is significantly affected.

Although it is true that drugs to slow down this effect are becoming more efficient, the truth is that A fully effective vaccine has not yet been developed that will put an end to this terrible disease once and for all. disease.

The influence of HIV on behavior

We asked ourselves at the beginning of the article if HIV can modify human behaviour. According to some studies that we are going to know next, everything seems to indicate that yes, HIV has the ability to modify the behavior of the host in a very specific way.

Specifically, what the latest research results seem to say is that HIV is altering the sexual behavior of people affected by this virus, and more specifically in gender individuals male. But when we talk about whether HIV can change human behavior, what exactly do we mean, within the sexual realm?

According to the studies, it seems that HIV is causing some very subtle but effective changes in the host, designed to cause it to have a higher sexual activity and even assume greater risks, maintaining relationships with a greater number of people. At the adaptive level, this mechanism makes a very obvious sense: maximum propagation.

A virus isn't exactly a living organism until it has attached itself to a host, but the laws of natural selection apply just the same. Therefore, those viruses that manage to “reproduce” (with the help of the host) in a more optimal way will tend to survive and thus end up propagating in successive generations.

Taking into account this mechanism and that HIV is transmitted through fluids, being the sexual route the simpler, it seems clear that the strategy of making the guest have the maximum number of encounters possible would be an excellent method to guarantee the survival of the virus, jumping from one individual to another, allowing it to reproduce.

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Studies on the behavior modification of this virus

This is the phenomenon that has been studied by, among others, Philip T. Starks and his collaborators, collecting the data from different works to carry out an analysis that would allow them to answer the question of whether HIV can modify human behavior. Based on the data observed, these authors affirm that, indeed, HIV is capable of such a task.

To reach this conclusion, Starks looked at the reports of the participants of the studies analyzed and realized that those individuals who were in the acute phase of HIV infection reported having a significantly higher number of sexual encounters and more risk behaviors (new partners, non-use of protection, etc.) than those who were in the non-acute phase.

Not only that, but also It seems to be observed that the higher the viral load in the patient, the more risky sexual behaviors performed by the male host.. Therefore, regarding the question of whether HIV can modify human behaviour, it would seem that the The answer is yes and that it also becomes more efficient in this task the higher the viral load that the patient has. individual.

Although, the researchers are cautious and ask the scientific community to put more emphasis on carrying out this type of studies to be able to resolve this question once and for all and give a categorical answer to the question that occupies. Only then will we know without any doubt whether HIV can change human behaviour.

Other cases of behavior modification due to viruses

To continue investigating whether HIV can modify human behavior, we can consult similar cases. And there are other viruses that also modify the behavior of the host, even if it is not human, to achieve similar effects. We are going to review some of the best known cases to have a better perspective of this phenomenon.

1. IIV-6/CrIV virus in crickets

For example, there is a virus called IIV-6 / CrIV that affects crickets, causing infertility. However, externally it does not generate any type of manifestation, so a cricket infected by this pathogen is visually indistinguishable from a healthy cricket. However, one of the effects that have been observed in individuals affected by the virus is precisely similar to the one we have reviewed in this article.

It seems that crickets that are infected by IIV-6 / CrIV, would see their sexual behavior altered, so that they would maintain more relationships and with a greater number of individuals. The objective is the same that we observed when studying the question of whether HIV can modify human behavior: to spread the virus to the maximum, ensuring its survival.

To observe this phenomenon in figures, we must know that a healthy cricket takes an average of 10 minutes to start making a courtship call before a female. On the contrary, a male infected with this virus took approximately 3 minutes to carry out this action, in search of a sexual relationship. As in the case of HIV, this behavior modification was carried out only in the case of the male hosts.

2. Massospora cicadin fungus on cicadas

There are other examples in the animal world. One of them is the fungus Massospora cycadin and the effect it has on cicadas. It seems that when an individual of this species is infected by this fungus, it suffers an effect similar to the one we saw when answering the question of whether HIV can modify human behavior.

In fact, the effect of Massospora cycadin it's even deadlier. It can cause the male host to flap its wings like a female would, to attract the attention of other male individuals and be able to come into contact to deposit the spores of this fungus on them.

The most dramatic part of the process is that the fungus gradually decomposes the body of the carrier cicada, but this does not make it lose effectiveness in its dispersal mechanism, for what can be observed cicadas that have detached their genitals and even the abdomen due to the infection, which continue to transmit the fungus to all the individuals that they can.

3. Entomophthora muscae in diptera

A case very similar to the one we have seen in the previous point is that of the fungus Entomophthora muscae and dipterous insects, which include mosquitoes, flies, horseflies and other animals. It is believed that this fungus provokes in these individuals a response that would be similar to the question of whether HIV can modify human behavior.

Bibliographic references:

• Adamo, S.A., Kovalko, I., Easy, R.H., Stoltz, D. (2014). A viral aphrodisiac in the cricket Gryllus texensis. The Journal of Experimental Biology.
• Boyce, G.R., Gluck-Thaler, E., Slot, J.C., Stajich, J.E., Davis, W.J., James, T.Y., Cooley, J.R., Panaccione, D.G., Eilenberg, J., De Fine Licht, H.H., Macias, A.M., Berger, M.C., Wickert, K.L., Stauder, C.M., Spahr, E.J., Maust, M.D., Metheny, A.M., Simon, C., Kritsky, G., Hodge, K.T., Humber, R.A., Gullion, T., Short, D.P.G., Kijimoto, T., Mozgai, D., Arguedas, N., Kasson, M.T. (2019). Psychoactive plant-and mushroom-associated alkaloids from two behavior modifying cicada pathogens. Fungal ecology. Elsevier.
• Coyle, M.C., Elya, C.N., Bronski, M., Eisen, M.B. (2018). Entomophthovirus: An insect-derived iflavirus that infects a behavior manipulating fungal pathogen of dipterans. BioRxiv.
• Starks, P.T., Kelsey, M.M.G., Rosania, D., Getz, W.M. (2020). Does HIV infection increase male sexual behavior? Evolution, Medicine, and Public Health.