Although the human papillomavirus (HPV) is known to be one of the most common sexually transmitted diseases (STDs), non-sexual transmission of the virus is also possible. A new study has unveiled the risks of this transmission and its findings have also revealed that HPV is immune to common disinfectants.
In the study "Susceptibility of high-risk human papillomavirus type 16 to clinical disinfectants" published in the Journal of Antimicrobial Chemotherapy Feb. 4, researchers grew an HPV strain called HPV16, known to be responsible for more than half of all HPV-associated cancers.
The researchers then tested the virus' susceptibility to 11 common disinfectants that included those made of ethanol and isopropanol because these ingredients are commonly used in hand sanitizers and surface disinfectants. Studying the susceptibility of hand sanitizers is crucial because there were earlier studies that found high levels of HPV DNA on the fingers of individuals with genital infection.
The researchers also tested glutaraldehyde, which is used to disinfect dental and medical equipment, as well as hypochlorite and peracetic acid. They found that the virus is susceptible to peracetic and hypochlorite acids and some of the other disinfectants but it is immune to alcohol-based disinfectants.
"Chemical disinfectants in hand sanitizer are commonly used in the general population to prevent the spread of infectious diseases," said study author Craig Meyers, a professor of Microbiology and Immunology at the Penn State College of Medicine in Hershey, Pennsylvania. "For flu or cold viruses they are very effective. But the data shows that they do nothing for preventing the spread of human papillomavirus."
The researchers also found that the virus is resistant to glutaraldehyde which means that medical instruments that are considered sterile may also serve as medium for HPV transmission.
"Chemical disinfectants used in the hospitals and other healthcare settings have absolutely no effect on killing human papillomavirus," Meyers said. "So unless bleach or autoclaving is used in the hospital setting, human papillomavirus is not being killed and there is a potential spread of HPV through hospital acquired or instrument or tool infection."
HPV has also been detected in children and virgins, so it was acknowledged in earlier studies that HPV can be transmitted non-sexually. The immunity of the virus to common disinfectants, which is revealed in the new study, shows risks of transmission and researchers call for policy changes in the use of disinfectant.
"Policy changes concerning disinfectant use are needed," the researchers wrote. "The unusually high resistance of HPV16 to disinfection supports other data suggesting the possibility of fomite or non-sexual transmission of HPV16."