Session Type: ePosters
Session Title: ePosters
Authors(s): A.L. Tomás (1), A. Reichel (1), P.M. Silva (1), N.B. Sedrine (2, 3), P.G. Silva (2, 3), J. Pinto (4), I. Calado (4), J. Campos (4), I. Silva (4), V. Machado (4), R. Laranjeira (4), P. Abreu (4), P. Mendes (2, 3), N.C. Santos (1)
Authors Affiliations(s): (1) Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisboa, Portugal, Portugal, (2) Castros S. A., Rua da Igreja Velha, 436, 4410-160 São Félix da Marinha, Portugal, Portugal, (3) MATGLOW, Rua Monte Lírio, 99, 4500-078 Espinho, Portugal, Portugal, (4) CeNTI - Centre for Nanotechnology and Smart Materials, R. Fernando Mesquita 2785, 4760-034 Vila Nova de Famalicão, Portugal, Portugal
Background:
The emergence of SARS-CoV-2 has substantially challenged our public health systems, with human, social, and economic costs worldwide. Although mass vaccination is reaping its rewards, the emergence of new dangerous variants, along with the risk of future pandemics, emphasizes the need for devising other efficient defense tools to mitigate viral transmission. It is known that the direct absorption of UV-C radiation by viral nucleic acids and/or proteins leads to the generation of photoproducts and viral inactivation. This highlights UV-C radiation as an economical, effective, and eco-friendly broad-spectrum antiviral tool. Previous studies demonstrated that UV-C radiation is efficient against SARS-CoV-2. However, coherent datasets for application on different surface compositions are still needed.
Methods:We assessed virus infectivity after UV-C exposure, through plaque assays, using a SARS-CoV-2 clinical isolate. Studies were conducted under BSL-3 conditions, with an ozone-free UV-C lamp emitting at 254 nm, under controlled environmental conditions (temperature and relative humidity). UV-C irradiance was quantified by using a 254 nm-calibrated sensor. Dose-response studies were conducted to determine the minimum dose required to achieve 3-log reduction (99.9 %) on porous and non-porous surfaces. The critical dose was validated on different non-porous surfaces, including different types of plastic, stainless steel, glass, and ceramics, as well as porous textile samples such as face masks, synthetic leather, bed linen and upholstery (car, chair, and public transportation seating).
Results:Our data show that UV-C irradiation is rapid and effective in inactivating SARS-CoV-2, on both non-porous and porous surfaces. However, the conducted dose-response studies demonstrated that the dose required to reduce 99.9 % of viral activity on porous surfaces was 20-fold higher than for non-porous surfaces, due to UV-C radiation shielding. These results highlight the need to customize UV-C treatment according to the properties of the surface to be sterilized.
Conclusions:Our findings will endorse the development of novel UV-C devices enabling surface-customizable inactivation protocols and thereby higher antiviral efficacies. We demonstrated that, if properly applied, UV-C radiation is a powerful tool against the spread of SARS-CoV-2, including potential new variants.
Keyword(s): SARS-CoV-2, UV-C irradiation, viral inactivationCOI Other: This work was developed within the UVTizer project (POCI-01-02B7-FEDER-062110) constituted by the consortium Castros, MATGLOW, CeNTI & iMM, co-financed by COMPETE 2020 and Portugal 2020 through ERDF.
Session Type: ePosters
Session Title: ePosters
Authors(s): A.L. Tomás (1), A. Reichel (1), P.M. Silva (1), N.B. Sedrine (2, 3), P.G. Silva (2, 3), J. Pinto (4), I. Calado (4), J. Campos (4), I. Silva (4), V. Machado (4), R. Laranjeira (4), P. Abreu (4), P. Mendes (2, 3), N.C. Santos (1)
Authors Affiliations(s): (1) Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisboa, Portugal, Portugal, (2) Castros S. A., Rua da Igreja Velha, 436, 4410-160 São Félix da Marinha, Portugal, Portugal, (3) MATGLOW, Rua Monte Lírio, 99, 4500-078 Espinho, Portugal, Portugal, (4) CeNTI - Centre for Nanotechnology and Smart Materials, R. Fernando Mesquita 2785, 4760-034 Vila Nova de Famalicão, Portugal, Portugal
Background:
The emergence of SARS-CoV-2 has substantially challenged our public health systems, with human, social, and economic costs worldwide. Although mass vaccination is reaping its rewards, the emergence of new dangerous variants, along with the risk of future pandemics, emphasizes the need for devising other efficient defense tools to mitigate viral transmission. It is known that the direct absorption of UV-C radiation by viral nucleic acids and/or proteins leads to the generation of photoproducts and viral inactivation. This highlights UV-C radiation as an economical, effective, and eco-friendly broad-spectrum antiviral tool. Previous studies demonstrated that UV-C radiation is efficient against SARS-CoV-2. However, coherent datasets for application on different surface compositions are still needed.
Methods:We assessed virus infectivity after UV-C exposure, through plaque assays, using a SARS-CoV-2 clinical isolate. Studies were conducted under BSL-3 conditions, with an ozone-free UV-C lamp emitting at 254 nm, under controlled environmental conditions (temperature and relative humidity). UV-C irradiance was quantified by using a 254 nm-calibrated sensor. Dose-response studies were conducted to determine the minimum dose required to achieve 3-log reduction (99.9 %) on porous and non-porous surfaces. The critical dose was validated on different non-porous surfaces, including different types of plastic, stainless steel, glass, and ceramics, as well as porous textile samples such as face masks, synthetic leather, bed linen and upholstery (car, chair, and public transportation seating).
Results:Our data show that UV-C irradiation is rapid and effective in inactivating SARS-CoV-2, on both non-porous and porous surfaces. However, the conducted dose-response studies demonstrated that the dose required to reduce 99.9 % of viral activity on porous surfaces was 20-fold higher than for non-porous surfaces, due to UV-C radiation shielding. These results highlight the need to customize UV-C treatment according to the properties of the surface to be sterilized.
Conclusions:Our findings will endorse the development of novel UV-C devices enabling surface-customizable inactivation protocols and thereby higher antiviral efficacies. We demonstrated that, if properly applied, UV-C radiation is a powerful tool against the spread of SARS-CoV-2, including potential new variants.
Keyword(s): SARS-CoV-2, UV-C irradiation, viral inactivationCOI Other: This work was developed within the UVTizer project (POCI-01-02B7-FEDER-062110) constituted by the consortium Castros, MATGLOW, CeNTI & iMM, co-financed by COMPETE 2020 and Portugal 2020 through ERDF.