Scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the U.S. National Institutes of Health, claim that COVID-19 can remain active in air droplets for hours and on surfaces for days.
The study published in the New England Journal of Medicine on 17 March investigates how long the virus can stay infectious in air droplets and different surfaces.
During the study, scientists recreated the scenario in which a COVID-19 patient deposits the virus on different everyday surfaces through coughing, sneezing, or touching them.
Scientists used a device to dispense an aerosol that replicated microscopic particles generated in a sneeze or cough.
The particles were dispersed in air and on everyday objects found in a household or a hospital setting such as plastic, stainless steel, cardboard, and copper.
The study findings reveal that COVID-19 particles can remain active in the air for 3 hours and on copper surfaces for more than 4 hours. Furthermore, it can remain infectious for 24 hours on cardboard over 72 hours on stainless steel and plastic.
As for the half-life of COVID-19, the findings show that the virus has a half-life of 66 minutes in air droplets. The virus has a half-life of 3 hours 30 minutes on cardboard, 5 hours 38 minutes on stainless steel, and 6 hours 49 minutes on plastic. COVID-19 has the shortest half-life on copper surfaces at 46 minutes, researchers have concluded.
The research team has urged public health professionals to undertake somewhat similar precautions to those for influenza and other respiratory diseases.
- Avoid touching nose, mouth, and eyes
- Cover sneeze or cough properly
- Wash hands frequently
- Maintain a considerable distance from sick people
- Self-isolation in case one falls ill
- Disinfect surfaces that a patient has touched
Read the findings in detail at the National Institutes of Health.