Tea Tree Oil (TTO) Eucalyptus oil (EUO) and Eugenol (CO) have been studied extensively in regards to the efficacy against several viruses, bacteria and fungus. A study by The American Association for Aerosol Research 2012* (1) found "both tested oils possess strong antiviral properties when used as fiber coating materials, capable of inactivating captured microorganisms within 5–10 min of contact on the fiber surface.
The antiviral activity of TTO was also successfully challenged in aerosol form by mixing viable airborne viral particles with oil droplets in the rotational aerosol chamber. The results look very promising for further development of virus inactivating procedures and technologies for air quality applications".
Furthermore additional studies*(2) found significantly reduced viral units for H1N1 and HSV1. For H1N1, a reduction greater than 99% (>2 log) was observed with 1% AB1 with a 60‐min contact time and a reduction greater than 99.99% (>4 log) with 80% and 40% AB1 after 60 min. For HSV1, a reduction greater than 99% was obtained with 1% and 40% AB1 after 60‐min contact time and a 99.99% reduction at 80% AB1 for 60 min.
These results are consistent with previous work, which showed that E. globulus and C. zeylanicum EOs had antiviral activity on H1N1 and HSV1 (Astani et al., 2010; Vimalanathan & Hudson, 2014). (1)*Oleg V. Pyankov, Evgeny V. Usachev, Olga Pyankova & Igor E. Agranovski (2012) Inactivation of Airborne Influenza Virus by Tea Tree and Eucalyptus Oils, Aerosol Science and Technology, 46:12, 1295-1302, DOI: 10.1080/02786826.2012.708948 *(2) Brochot A, Guilbot A, Haddioui L, Roques C. Antibacterial, antifungal, and antiviral effects of three essential oil blends. Microbiologyopen. 2017;6(4):e00459. doi:10.1002/mbo3.459