Coronavirus dan virus influenza sensitif kepada keasidan aerosol. Penyahaktifan pantas coronavirus yang dimediasi pH adalah mungkin dengan memperkayakan udara dalaman dengan paras asid nitrik yang tidak berbahaya. Sebaliknya, penapis udara dalaman mungkin secara tidak sengaja mengeluarkan asid meruap sehingga memanjangkan kegigihan virus bawaan udara. Pemahaman baru ini boleh sangat membantu dalam mengawal penghantaran bawaan udara terutamanya dalam persekitaran dalaman seperti tetapan hospital.
Jangkitan pernafasan yang disebabkan oleh mempengaruhi and koronavirus-koronavirus adalah masalah berterusan yang penting untuk kesihatan manusia. Influenza sahaja menyebabkan lebih 400,000 kematian setahun di seluruh dunia. Pandemik COVID-19 yang berterusan disebabkan oleh coronavirus novel SARS CoV-2 has caused over 6 million deaths so far plus immense human suffering and unthinkable economic damages to world economy. Therefore, minimising transmission of these virus is an extremely important priority.
It is known that their dominant mode of transmission is airborne. These infections are contracted by breathing in contaminated air. The expiratory aerosol particles act as vehicles for the transmission of influenza virus and novel coronavirus SARS-CoV-2. Hence the importance of wearing face coverings. It is hypothesized that the virus can remain in the air for about 3 hours with a half-life of 1.1 hours.
Needless to say, that rapid inactivation of these virus would greatly contribute to limiting their transmission.
It is known that the enveloped virus like influenza and corona virus are inactivated in acidic conditions however level of acidity of expiratory aerosol particles and its role on inactivation of the virus was unknown.
In a recent study published in the preprint medRxiv, the researchers examined this aspect for influenza and coronaviruses. They found that the aerosol particles exhaled into indoor air become mildly acidic (pH ≈ 4). This acidic condition rapidly inactivated influenza-A virus within minutes but the novel coronavirus SARS-CoV-2 required days for inactivation. Further, if the indoor air were enriched with non-hazardous levels of nitric acid, the acidity of the aerosol dropped by up to 2 units which in turn reduced the inactivation times for both viruses to below 30 seconds. This pH-mediated 99%- reduction in inactivation time could be of great significance in rapid inactivation of these viruses in indoor settings thus helping reduce community spread considerably.
Berdasarkan penemuan di atas, penggunaan penapis udara dalaman perlu dipertimbangkan dengan teliti kerana sebarang penyingkiran asid meruap yang tidak disengajakan dari udara dalaman boleh mengurangkan keasidan aerosol yang mengeluarkan nafas dan memanjangkan bawaan udara. virus kegigihan.
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Rujukan:
- COVID-19: Apakah Maksud Pengesahan Transmisi Udara Virus SARS-CoV-2? Eropah saintifik. Disiarkan pada 17 April 2021. Boleh didapati di http://scientificeuropean.co.uk/covid-19/covid-19-what-does-confirmation-of-the-airborne-transmission-of-sars-cov-2-virus-mean/
- Luo B., et al 2022. Keasidan aerosol ekspirasi mengawal kejangkitan virus influenza bawaan udara dan SARS-CoV-2. Pracetak medRxiv. Disiarkan pada 14 Mac 2022. DOI: https://doi.org/10.1101/2022.03.14.22272134
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