In general, the answer is yes. However, that doesn't apply to all circumstances. Sharing a cup with your partner will not give you a sexually transmitted disease (STD). However, if your partner has herpes and you apply your lips on the rim of his or her cup, you might get herpes too. Also, jumping in a pool with strangers won't result in a sexually transmitted infection (STI). But, having sex in a pool with an infected person can give you an STD. Sharing a hot tub and getting intimate with an individual, though, might lead to an STD. 

Having sex in the pool and the risk of getting an STD

Casually swimming in a swimming pool does not put you at high risk of getting an STD. Firstly, the water in the swimming pool has chlorine, which is extremely efficient in killing viruses and bacteria. Also, most STDs need actual sexual contact and fluids to spread. These two reasons make it extremely rare to catch an STD from a swimming pool. Therefore, they are safe to swim. On the contrary, having sex in a pool significantly increases your chances of catching an STD, but specifically urinary tract infections (UTIs) and yeast infections. However, contrary to hot tubs, the temperature of the water does not favorize the survival of pathogens. Therefore, when considering jumping in a pool, do not stress over STDs. The scenario of catching an STI while swimming in a pool is remarkably rare, and there is no evidence to support the opposite. 

I am worried I contracted an STD from having sex in a pool

If you had sex in a swimming pool and you're worried your sex partner gave you an STD, you might need to get tested. Knowing what your partner has is extremely important in getting tested for the correct pathogen. For instance, if your partner has chlamydia and tells you so after sex, you might need to get tested for chlamydia. You can do so with an STD rapid kit test at home. Keep in mind that chlamydia and gonorrhea often coexist. For that reason, you can get a combo STD kit test. Whatever the case, do not worry too much. STD kit tests are accurate and reliable methods of getting tested for STDs. Also, most STDs are curable, and if not, manageable with medication. 

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Incubation Period of STDs

Having sex in a hot tub and the risk of getting an STD

Being in a hot tub with an STD-positive individual might put you at considerable risk for acquiring an STI. The high temperature of the water favors the growth and survival of pathogens. Sexually transmitted pathogens can pass in between the fibers of swimwear, making infection a possible scenario. The risk increases even more if you engage in sexual activities with an infected individual inside a hot tub. However, for that to happen, genital fluids are necessary. Therefore, in the lack of sexual arousal, genital fluids remain in the body, decreasing the risk of infection significantly. In other words, just being in the same hot tub with an infected individual and casually talking to each other does not mean you will get an STD. But, if there is sexual activity, it should be done safely. 

I am worried I contracted an STD from a hot tub, what should I do?

Being worried is fine. Most of the people care about their health, especially when it comes to sex. STDs are often asymptomatic and, therefore, difficult to diagnose clinically. Also, many individuals that received a diagnosis after a routine check-up were unaware they had an STD. Not knowing you have an STI can make people spreading it to new partners or to people with which they have casual sex. If you are worried you contracted an STD from a hot tub, you can get tested at home with an STD rapid kit test. These tests are easy to use and will provide you with fast and accurate results in less than twenty minutes. 

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Can I get an STD from someone else's bed/sharing towels?

Drinking water from the same cup and the risk of STDs

Drinking water from the same cup of a person with an STD will not give you an STD. Most STDs require sexual contact to spread. However, some viral STIs may stay in the rim of the cup and spread to you. Such an example is herpes. It is a viral STD that has two types. The first type is HSV-1, known as oral herpes. The second type is HSV-2, known as genital herpes. The symptoms of herpes simplex begin with one or multiple blisters on the mouth, genitals, or anus. After some time, they erupt, turning into painful small sores. The virus spreads through oral secretions or skin sores. Therefore, you can get herpes simplex by kissing or sharing objects used for the hygiene of the mouth. When an infected individual drinks from a cup, he or she might spread the virus to the rim of the cup. Drinking from that cup may transmit the infection to you. 

 

Can you get HIV from anything other than sex?

Studies suggest that the virus responsible for HIV infection cannot stay outside the human body for a long time. According to research, 90% to 99% of the virus becomes inactive in a few hours. However, although the process of drying inactivates the virus, it can remain active in some cases, in dried body fluids. Regardless of the ability of the virus to stay active in rare cases, as a rule, you cannot get HIV from anything other than sex. 

Can HIV survive in water?

Shortly, the answer is no. HIV cannot survive in water. Therefore, you cannot contract HIV by sharing a cup of water with an HIV-positive person. Also, you cannot get the infection through swimming or sharing the same hot tub with an HIV-positive individual. The only methods of HIV transmission are through blood and unprotected vaginal or anal sex. Also, keep in mind that usually currently affected individuals that receive antiretroviral treatment have undetectable viral levels.