The virus responsible for COVID-19, SARS-CoV-2, is primarily transmitted through respiratory droplets and aerosols, but concerns remain about its ability to spread through contaminated surfaces, a route known as fomite transmission. Understanding how long the virus remains viable on soft, porous materials is important for home hygiene, especially when caring for someone who is ill. The survival time of the virus on bedding differs significantly from its persistence on hard surfaces, making the risk profile unique for fabric items.
How Long SARS-CoV-2 Survives on Fabric
The survival time of infectious SARS-CoV-2 on bedding fabrics is generally much shorter compared to non-porous materials like plastic or stainless steel. Scientific studies indicate that textiles, particularly those made of cotton, tend to inactivate the virus relatively quickly. On highly absorbent cotton, which is common in sheets, the viable virus may persist for as little as a few hours up to a few days, depending on specific conditions.
This faster decay rate is due to the porous nature of fabric, which quickly wicks away moisture from the deposited respiratory droplets. The virus needs a thin layer of moisture to maintain its structure and remain infectious, but the rapid drying and absorption by textiles accelerate its breakdown. In contrast, the virus can remain viable for a week or longer on smooth, non-porous surfaces under certain laboratory conditions.
Synthetic materials, such as polyester or polycotton blends often found in pillowcases and comforters, can sometimes support viral viability for a slightly longer duration than pure cotton. Some research has shown infectious virus persisting on synthetic fabrics for up to 72 hours. Ultimately, bedding is considered a lower-risk surface for transmission compared to hard, high-touch areas, but risk remains given the high concentration of droplets that can be deposited by someone who is coughing or sleeping on a pillow.
Environmental Conditions Affecting Persistence
The actual persistence of the virus on any surface, including bedding, is heavily influenced by the immediate environment. Temperature plays a significant role, with higher ambient heat causing faster viral decay. Studies have demonstrated that increasing the temperature from 20°C (room temperature) to 40°C can drastically reduce the virus’s survival time on cotton to less than 24 hours.
Humidity is another factor, though its effect is complex; extremely low or high humidity can both contribute to viral inactivation. The amount of virus deposited, known as the viral load, also affects how long it takes for the virus to become non-infectious.
The specific material composition of the bedding can also alter the survival window. These variables mean that any specific number for viral survival on sheets and pillows represents a range of possibilities rather than a single fixed duration.
Best Practices for Laundering Contaminated Bedding
The most effective way to eliminate the virus from bedding is through proper laundering, which relies on a combination of detergent, heat, and mechanical action. Standard laundry detergent is highly effective at destroying the SARS-CoV-2 virus because its surfactants break down the fatty outer layer, or lipid envelope, of the virus. This chemical process renders the virus unable to cause infection.
When washing bedding used by someone who is sick, the warmest water setting appropriate for the fabric should be used, following the manufacturer’s instructions. While detergent alone is potent, using hot water, generally at or above 60°C, provides an added layer of assurance by directly inactivating the virus. The mechanical agitation of the washing machine also helps to remove viral particles from the fabric.
The drying cycle is also a powerful tool for disinfection, as the high heat is a significant viral inactivator. Items should be dried completely on the highest heat setting that is safe for the material.
When handling soiled laundry, it is best to avoid shaking the items, as this can aerosolize viral particles into the air. Wearing disposable gloves and washing hands thoroughly immediately after handling the laundry minimizes any risk of transfer.