HIV cannot survive for long outside the body. Environmental factors influence the survival of the virus and these include the:
- temperature,
- pH,
- sunlight,
- and humidity.
The HIV virus can be detected in the environment outside of the body for several days. However, studies by the CDC [1] have shown that 90 to 99% of the HIV virus becomes non-infectious within several hours when exposed to a dry environment. Therefore, the risk of acquiring HIV through the environment is negligible and there have been no reported cases of HIV transmitted from environmental contact.
Neisseria gonorrhoea is the bacteria that causes gonorrhoea. The bacteria thrive in a moist environment and is quickly killed when dried [2]. It has been shown to survive up to 2 hours on environmental surfaces. However, studies attempting to culture them from toilet seats were unsuccessful.
Treponema pallidum is the bacteria that causes syphilis. This bacterium is killed by heat, sunlight and drying [3]. It also survives best in a low oxygen environment and therefore cannot survive for long outside the body. Overall, the risk of acquiring a sexually transmitted infection through environmental contact is minuscule.
References:
1. Recommendations for Prevention of HIV Transmission in Health-Care Settings. https://www.cdc.gov/mmwr/preview/mmwrhtml/00023587.htm. Published 2019. Accessed December 12, 2019.
2. Hill SA, Masters TL, Wachter J. Gonorrhea – an evolving disease of the new millennium. Microbial Cell. 2016;3(9):371-389. doi:10.15698/mic2016.09.524
3.Human Reproductive Biology. Google Books. https://books.google.com.sg/books?id=pfiZfui2XLIC&pg=PA497&lpg=PA497&dq=Treponema+pallidum+killed+by+heat,+sunlight+and+drying&source=bl&ots=XrgUT4887v&sig=ACfU3U3yGMBDJICscJP5KOCyk3-HbkK5_Q&hl=en&sa=X&ved=2ahUKEwiE-emn7a_mAhWScc0KHYLCAmIQ6AEwDXoECAwQAQ#v=onepage&q=Treponema%20pallidum%20killed%20by%20heat%2C%20sunlight%20and%20drying&f=false. Published 2010. Accessed December 12, 2019.
