Self-Inoculation - Giving Yourself a Disease

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What is Auto-Inoculation or Self-Inoculation?

Auto-inoculation, or self-inoculation, occurs when a person transfers a disease from one part of their body to another. Self-inoculation frequently happens when someone scratches or rubs a sore and then touches uninfected skin. Many diseases can be spread by self-inoculation in this way, including chicken pox.

In these cases, self-inoculation may be similar to transmission by fomites.

If, for example, a person ends up with HPV under their nails, they could transmit it either to a partner or themselves. This can happen not just with STDs but other contagious skin conditions, like plantar warts. That is why, in general, doctors encourage people to avoid rubbing sores and warts. They may even recommend covering these lesions to reduce the risk of contact. (Scratching sores can also lead to secondary infections. Those may be even more difficult to heal than the original condition.)

Common Misspellings: auto-innoculation, self-innoculation

Alternative Spelling: autoinoculation

Examples of STDs Where Auto-Inoculation May Be an Issue

Molloscum contagiosum is very easy to spread by self-inoculation. Rubbing a sore can auto-inoculate viral particles to the surrounding skin and lead to additional areas of infection.

HPV is also known to spread through autoinoculation. In fact, warts on the hands can potentially spread to the genitals.

This is true even when those warts are caused by types of HPV not normally associated with genital warts. HPV can also be self inoculated from the genitals to the mouth.

It is possible for the herpes simplex virus to spread by autoinoculation. There has not been much research on how common this might be.

It is conceivable that self inoculation from mouth to genitals might be possible, although there are not clear reports.


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