Are STDs transmitted only by sexual contact or by mixing blood? Which STDs are only sexually transmitted?

Few. Perhaps trichomonas and gonorrhea, although the latter could conceivably be transmitted through blood under some unusual circumstances.
Theoretically none. But trichomonas would be difficult to get through blood, as would gonorrhea, although the latter is possible on a theoretical basis. It would also be very unusual to get herpes except by sexual activity unless you don't consider oral sex, sex.

Related Questions

If STDs are sexually transmitted how can you get them by touching blood that's out in the open, ?

Termanology. The category of "sexually transmitted disease" is just a group of problems that can pass sexually. The germs involved are not limited to that mode of transmission. Hepatitis B can transmit sexually or through a tainted needle, or contact with blood of an infected person. The same goes for AIDS, syphilis and many other diseases. Some are less likely to pass through non sexual means.

Is it plausible that bed bugs could spread sexually transmitted disease's since it feasts on human blood?

Doesnt work that way. I see your logic and that is a good thought, but you don't have to worry about that. Bed bugs are gross, but they don't spread stds.
Plausible not likely. No recorded cases that I know of. Not for bed bugs or kissing bugs. Mosquitoes can transfer malaria from one human to another but I know of no cases of hiv/aids transmitted by this vector. That should be reassuring because both malaria & HIV are endemic to the same areas of tropical africa. Anyone else have information on this terrorfying scenario?

Does full blood test pick up sexually transmitted disease's? Or what ones does it pick up?

Several. There are thousands of different blood tests & sexually transmitted include hiv, hepatitis b, syphilis, & hepatitis b (i think). Gonorrhea, chlamydia, trichomonas, chancroid, lymphogranulosis venereum, herpes, hpv, candida, and molluscum contagiosum, etc. Are detected by cultures of genital tissues. This might not be all inclusive or exact, but you get idea. Crabs are directly visualize.

Can doctors test you for sexually transmitted diseases before you can donate blood?

Yes, but... All organ donors will be checked for all possible blood-borne / body-fluid-borne diseases such as HIV, syphilis, CMV, hep-B/hep-C, etc. Ask the detail at the center for organ harvesting. But, indeed, it is nice of you to think and ask this question for social conscience and safety. I salute you. Best. ..

What forms of sexual contact can lead to stds?

Any. Vaginal, anal, oral sex, and even touching private parts can transmit infectious agents. Condom use helps but is not fool proof and does not prevent hpv.

Could an STD be passed through minimal sexual contact?

Variable. Some are easier to pass than others (gonorrhea) while some require more contact (hpv).Sometimes a carrier is not actively shedding the germ so they would not be contagious at the time.

Do std's spread through oral contact/saliva (no direct sexual contact)?

Sometimes. If the infecting organism gets to the mouth by contact with an infected area one one person, another person could get the infection by kissing, but if is unusual.
Depends on STD. Oral contact can spread many bacterial stds period. This is especially true with a person with an active infection open sore hidden in the back of the mouth. Hiv doesn't as there is something in the saliva that kills it. Research is still being done to discover why.

Is PID itself transmittable through sexual contact or is it the initial STD that is the transmittable one?

Initial. Pelvic Inflammatory Disease is dangerous and usually requires hospitalization and IV medication. The germ behind it can be passed to a partner, but the PID represents the response of the person that gets infected. The same germ may not be able to do as much damage to another person. There is no male equivalent.

How are STI and STD spread? If two people have not had any sexual contact with any other person can an STI or STD be spread through anal or oral sex?

Person to person. STDs are spread from person to person in various ways. Some through transmission of fluids (gonorrhea, chlamydia, trichomoniasis, HIV). Others are spread through contact (Herpes, syphilis, HPV). One of you would have to have an STD to give it to the other. If neither person has ever had any sexual contact of any kind then they can not spread and STD.
Mutual monogamy. Mutual monogamy, assuming both parties are negative for STD's, usually guarantee absence of transmission. The exception is previous exposure to Herpes which has not had any "outbreaks" over a period of time until resuming contact with another partner.