The COVID-19 pandemic raised concerns about the virus’s ability to linger on surfaces and potential transmission through frequently touched objects. Understanding how long the SARS-CoV-2 virus, which causes COVID-19, remains viable on various materials, including paper, helps inform public health practices. While the primary mode of transmission is through respiratory droplets, surface contamination, known as fomite transmission, is also a consideration. This article focuses on the survival of SARS-CoV-2 on paper and practical advice for handling paper items.
How Long the Virus Survives on Paper
Studies indicate that SARS-CoV-2 survives for a shorter duration on porous surfaces like paper compared to non-porous materials such as plastic or stainless steel. One study observed the virus remained viable for approximately three hours on printing and tissue paper. Another suggested a range of four to five days for paper, while cardboard showed viral viability for up to 24 hours. The porous nature of paper plays a role in the virus’s reduced longevity.
Factors Affecting Virus Survival
The survival time of SARS-CoV-2 on paper and other surfaces is influenced by environmental and material factors.
Environmental Factors
Temperature, humidity, and exposure to ultraviolet (UV) light significantly impact how long the virus remains infectious. Higher temperatures and humidity can lead to faster inactivation of the virus.
Material Factors
Porous materials like paper and cloth allow respiratory droplets containing the virus to spread and evaporate more quickly. This accelerated evaporation of the thin liquid film left after a droplet dries out contributes to the faster decay of the virus on these surfaces. The specific composition and absorbency of different paper types also affect how quickly virus-laden droplets dry and how long the virus persists.
Safe Handling of Paper Items
While the risk of contracting COVID-19 from handling paper items like mail or documents is low, especially compared to person-to-person transmission, simple precautions can minimize any potential risk. Health experts, including the World Health Organization and the U.S. Centers for Disease Control and Prevention, indicate no evidence that COVID-19 is widely spread through mail or parcels. The main concern with any surface contact is the transfer of the virus to mucous membranes through touching the face. After handling mail, packages, or other paper items, wash your hands thoroughly with soap and water for at least 20 seconds, or use an alcohol-based hand sanitizer. Avoiding touching your face before hand hygiene is also a good practice.