8 ms·
> Do the parasites make their hosts more attractive so they are more likely to be passed on, or do more attractive people have more sex that gives them opportun
by axlee 5y ago
> Do the parasites make their hosts more attractive so they are more likely to be passed on, or do more attractive people have more sex that gives them opportunities to be infected?
T. Gondii reproduces in felines, and is transmitted initially through their feces to other hosts. Humans catch it most often through infected food (meat, vegetables) or liquids (water, milk). Humans cannot transmit T. Gondii to other humans, unless pregnancies, organ transplants or cannibalism are involved.
So, regardless of how attractive an host is, he won't have more or less opportunities to be infected with T. Gondii than anyone else. This is not a STD.
Unless there is some sort of correlation between attractiveness and eating poorly corked meat.
- holub008 5y agoHow about correlation between attractiveness and owning cats? Attractiveness and having a larger number of partners, which increases odds of exposure to cats / T. Gondii? These hypotheses seem plausible enough that I believe the authors are wrong in claiming causality.
- hunterb123 5y agoUnless people are hooking up in barns I don't think frequenting partners that own cats would be correlated. House cats generally eat kibble, not infected mice. Even then you'd have to infect yourself with the cat while getting together, as humans don't transfer to each other. Personally I don't think there's any causation here at all with attractiveness directly. It may be correlated with more outdoorsy people, those people are probably more attractive on average.
- jjj123 5y agoI don’t understand why you keep mentioning hooking up, that seems irrelevant since it’s been clarified this is not an STD. The parent comment was saying people who own cats could be more attractive on average, and people who own cats are more likely to get toxoplasmosis.
- hunterb123 5y ago> Attractiveness and having a larger number of partners, which increases odds of exposure to cats Hooking up was simply an example of why the person would be at the other person's environment. Replace it with getting together if you're getting hung up on it. Whether or not the humans met up to have sex, talk, stand on their head, or whatever is irrelevant. The point was house cats generally don't eat infected mice, if you're hanging out in barns or on the patio with outside cats, sure maybe.
- 8note 5y agoMice can pretty easily show up indoors
- holub008 5y agoI wasn't implying infection was occurring during sex, but rather by being in the environment (many people stay around partners for more than sex).
- hunterb123 5y agoI wasn't implying that either, indicated by "as humans don't transfer to each other." I painted a scenario where your environment would occur, and dispute it by saying those cats in that environment generally aren't infected Unless those attractive people are hanging out in barns or patios with outside cats. Now that could be the case if you go at it from an outdoors perspective, outdoorsy people may be more attractive on average, and they may encounter infected cats more on average.
- mulmen 5y agoThere are house cats all over my neighborhood. I can think of four in the area. It’s extremely common to have an outdoor cat as a pet. Your characterization of cat ownership is unrealistic.
- hunterb123 5y agoMost cat owners I know have inside only cats, as do I. I do know of 3 cats that roam my neighborhood, they could be from quite far away as outdoor cats have a large range. I guess anecdotes from you or I isn't really telling if an indoor or outdoor majority of cat ownership is "unrealistic". Maybe we need a study :p Do outside cat owners generally let their cats inside their home?
- mulmen 5y agoDoesn’t matter, they’re domestic cats and you already explained a circumstance where they could expose visitors and owners. Half the year here is a hospitable climate for outdoor recreation and cat survival. Half of it isn’t. I have seen these cats for multiple years so unless they have an outdoor cat house (something I have never seen in my life) then I suspect they come inside. The ratio of cat owners with outdoor cats is irrelevant. They exist and they are common. That’s enough to sink your assertions.
- eurasiantiger 5y agoJust want to note that kibble is not the best of foods for cats, especially not as the only food: it tends to cause urinary blockages which are a veterinary emergency.
- dtgriscom 5y ago> Humans cannot transmit T. Gondii to other humans, unless pregnancies (phew.. I'm male) > organ transplants (none needed yet) > or cannibalism are involved. (oh, NO!!!!!)
- stuckinhell 5y agoI think the research is still incomplete on human to human transmission looking at some of the commenter's research article links. It looks like it CAN spread via sex.
- abeppu 5y agoI think the point of the article disagrees with you? Like, to my reading, the hypothesis is that T. Gondii should be under selective pressure to support its host mating, because that aids its spread. From the background paragraph: > However, if parasites diminish a host’s health and attractiveness to such an extent that finding a mate becomes almost impossible, the parasite would decrease its odds of reproducing and passing to the next generation. There is evidence that Toxoplasma gondii (T. gondii) manipulates phenotypic characteristics of its intermediate hosts to increase its spread. And the conclusions paragraph: > Our results suggest that some sexually transmitted parasites, such as T. gondii, may produce changes in the appearance and behavior of the human host, either as a by-product of the infection or as the result of the manipulation of the parasite to increase its spread to new hosts. Taken together, these results lay the foundation for future research on the manipulation of the human host by sexually transmitted pathogens and parasites. It's hard to read that as anything other than the authors classifiying T. gondii as a "sexually transmitted parasite". I don't know how to reconcile that with what you're saying. Am I missing something?
- wzdd 5y agoContrary to what you wrote about T. gondii definitively not being sexually transmitted between humans, the article links to several studies which postulate exactly that. The paragraph is: > Since reports that T. gondii can be a sexually transmitted parasite in humans are relatively recent (e.g., Flegr, Klapilová & Kaňková, 2014; Hlaváčová et al., 2020; Kaňková, Hlaváčová & Flegr, 2020; Tong et al., 2021), many questions and hypotheses still need to be properly formulated and tested in further studies. The basis for this theory is that T. gondii cysts have been found in human ejaculate, which means it could for example be transmitted through oral sex. There does not appear to be any conclusive proof that this has happened, but apparently these are viable cysts which, if swallowed in any other context, would result in infection, so it's plausible. This non-"pregnancies, organ transplants or cannibalism" route is the basis for a lot of this article's theorising about T. gondii benefiting from raising its host's likelihood of having sex.
- lesserknowndan 5y agoThis is the conclusion in the Abstract: Our results suggest that some sexually transmitted parasites, such as T. gondii, may produce changes in the appearance and behavior of the human host, either as a by-product of the infection or as the result of the manipulation of the parasite to increase its spread to new hosts. Taken together, these results lay the foundation for future research on the manipulation of the human host by sexually transmitted pathogens and parasites.