Some air filters or purifiers may be able to remove very small virus particles from the air, and may be effective in areas with poor ventilation and air exchange. However there is little evidence for efficacy of portable air filters for reducing COVID transmission in homes, and they should not be used as a primary method of prevention.
The best ways to reduce transmission of COVID and many other viruses are to remain physically distant from those not in your household, wear a mask, wash your hands for at least 20 seconds with soap and warm water, and safely disinfect high-touch surfaces (door knobs, light switches, etc).
Air purifiers can effectively remove indoor air pollutants like dust, pollen, and some gases. If you do choose to use an air purifier, choose one with a HEPA (High Efficiency Particulate Air) filter that is properly rated for the size of your space.. We do not recommend PECO or PCO filters or other emerging ionizing technologies as these have been shown to be less effective than HEPA filters at capturing Sars-CoV-2 (COVID viral) particles. In addition, some of these devices generate ozone which can irritate the lungs.