SARS-CoV-2 suggests that COVID-19 may remain viable for hours to days, on inanimate surfaces, such as metal, glass, or plastic, for up to 9 days. With exponentially rising COVID-19 cases in the United States, commercial disinfect supplies are in high demand and will unquestionably be limited in the near future. We will have to get creative with available resources, all the while taking safety precautions to ensure our efforts improve and not worsen the ongoing situation.
While the exact viral load on inanimate surfaces is unknown during an outbreak, it is critical to disinfect frequently touched surfaces. With rapidly diminishing availability of commercial cleaning supplies, simply diluted bleach, which is readily available, can effectively disinfect homes, offices, and environment to prevent sustained transmission from inanimate objects. As with many disinfectants, minimizing long-term skin contact and ensuring good ventilation can minimize clinical toxicity.
The virus can efficiently be inactivated by 62% to 71% ethanol, 0.5% hydrogen peroxide, or 0.1% sodium hypochlorite within 1 minute. Dilutions of ∼0.1% sodium hypochlorite are clinically effective with minimal irritation or sensitization.5 One should be mindful that corrosive injury on mucous membrane/skin contact is possible with excess volumes or mishandling, so appropriate caution and moderation are necessary. This solution should ideally be used within 1 month of preparation and stored in a closed, opaque container at room temperature.
∼0.1% sodium hypochlorite can be made by a roughly 1:50 dilution of household bleach (∼5.25% to 6% sodium hypochlorite) in tap water. The proposed formulation is shown to disinfect surfaces of the novel coronavirus. The Centers for Disease Control and Prevention (CDC) also recommends an approximately 1:50 dilution to disinfect COVID-19, explicitly noting 5 tablespoons (one-third cup) bleach per gallon of water or 4 teaspoons bleach per quart of water.