The virus remains infectious on steel surfaces for up to 30 days, but can be effectively inactivated by alcohol-based disinfectants.
Smallpox viruses are notorious for their ability to remain infectious in the environment for a very long time. A study by the Department of Molecular and Medical Virology at Ruhr-University Bochum, Germany, showed that temperature is a key factor in this process: At room temperature, a monkeypox virus capable of reproducing can survive on a stainless steel surface for up to eleven days. , and at four degrees Celsius for up to a month. Thus, it is very important to disinfect surfaces. According to the study, alcohol-based disinfectants are very effective against monkeypox viruses, while hydrogen peroxide-based disinfectants have proven ineffective. The team published their findings in Journal of Infectious Diseases On May 2, 2023.
Since 2022, more and more monkeypox virus has been transmitted from one human host to another. Although the infection is primarily caused by direct physical contact, it is also possible to catch the virus through contaminated surfaces, for example at home or in hospital rooms. “Spox viruses are known for their ability to remain infectious in the environment for a very long time,” explains Dr. Toni Meister from the Department of Molecular and Medical Virology at Ruhr-University Bochum. “For monkeypox, we didn’t know the exact time frames yet.”
So the researchers studied it by applying the virus to sterile stainless steel plates and storing them at different temperatures: at four degrees, at 22 degrees, which roughly corresponds to room temperature, and at 37 degrees. They determined the amount of infectious virus after different time periods ranging from 15 minutes to several days to weeks.
Viruses remain contagious for a long time
Regardless of the temperature, there was little change in the amount of infectious virus over the first few days. At 22 and 37 degrees, the virus concentration decreased significantly after only five days. At 37 degrees, no virus capable of reproducing was detected after six to seven days, at a temperature of 22, it took ten to eleven days until infection was no longer possible. At four degrees, the amount of virus decreased sharply only after 20 days, and after 30 days there was no longer any risk of infection. “This is consistent with our experience that people are still able to infect monkey mites from surfaces in the home after approximately two weeks,” notes Professor Ike Steinmann, Chair of the Department of Molecular and Clinical Virology.
To reduce the risk of infection in the event of an outbreak, it is very important to disinfect surfaces. This is why researchers tested the effectiveness of five common disinfectants. They found that alcohol- or aldehyde-based hand sanitizers reliably reduce the risk of infection. However, a hydrogen peroxide-based disinfectant did not inactivate the virus effectively enough in the study. “Our results support the WHO recommendation to use alcohol-based surface disinfectants,” concludes Toni Meister.