Scabies is a skin infestation caused by the human itch mite, Sarcoptes scabiei, a microscopic parasite that burrows into the upper layer of the skin to live and lay eggs. While medical treatment eliminates mites from the body, cleaning the surrounding environment is equally important to prevent re-infestation. This decontamination focuses on clothing, bedding, and towels. The dry cleaning process is a confirmed method for eradicating these mites and their eggs from delicate or non-washable fabrics.
How Long Scabies Mites Survive Off the Body
The need for cleaning protocols is based on the limited lifespan of the scabies mite once it is separated from a human host. In typical household conditions, which include normal room temperature and average humidity, the Sarcoptes scabiei mite generally does not survive for more than two to three days. This survival window of approximately 48 to 72 hours is the critical factor that informs all decontamination strategies.
The mite’s ability to survive is highly dependent on environmental factors, particularly temperature and humidity. Survival is significantly reduced at high temperatures, but it can be prolonged in cooler, more humid environments. However, even if the mite survives longer under certain conditions, its ability to move and re-infest a host is compromised at temperatures below 20°C.
Dry Cleaning Solvents and Heat
Dry cleaning is a highly effective method for eradicating scabies mites and their eggs from textiles. This process is lethal due to the combination of powerful chemical solvents and intense heat. It is the recommended treatment for items that cannot withstand the high temperatures of a conventional hot water wash cycle.
The chemical solvents used in commercial dry cleaning are toxic to the mites, penetrating the fabric fibers to destroy the organisms. Following solvent treatment, garments are subjected to a high-temperature drying and pressing cycle. Temperatures exceeding 50°C (122°F) for just 10 minutes are sufficient to kill both adult mites and their eggs. This two-pronged approach makes dry cleaning a reliable option for delicate materials like wool suits, silk garments, and leather goods.
Managing Non-Washable Items Without Dry Cleaning
When commercial dry cleaning is not feasible, alternative non-laundry methods can effectively decontaminate non-washable items. The primary strategy relies on exploiting the mite’s inability to survive without a host for an extended period.
Isolation and Sealing
A common method is to seal items in an airtight plastic bag, such as a garbage bag, and isolate them. This cuts off access to a human host, ensuring the mites starve. Although mites die within 72 hours, health authorities recommend leaving items sealed for a minimum of three days. Sealing items for up to a full week (five to seven days) guarantees the death of any newly hatched larvae from eggs.
Heat and Vacuuming
For items that can tolerate heat but not water, a hot dryer cycle can be used. Placing items in a dryer on the hottest setting for at least 20 minutes achieves the required temperature of 50°C or higher to kill the mites and eggs. Large items like mattresses or upholstered furniture can be thoroughly vacuumed to remove mites. The vacuum bag must then be sealed and discarded immediately.