3
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      N-95 Face Mask for Prevention of Bird Flu Virus: An Appraisal of Nanostructure and Implication for Infectious Control

      Lung

      Springer-Verlag

      Influenza, Avian Influenza, Pore Wall, H5N1 Virus, Universal Precaution

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Bird flu or avian flu, caused by the H5N1 virus, is a new emerging infectious disease. There has been a worldwide problem regarding avian influenza infections in poultry since 1997. It is noted that this H5N1 virus jumped the species barrier and caused severe disease with high mortality in humans in Vietnam and Thailand (http://www.thaigcd.ddc.moph.go.th/avianflu_FAQ_en.html). For prevention of airborne viral infection, N-95 masks are the gold standard that might be applicable to the bird flu infection [1]. Because most viruses are approximately spherical, the virus is modeled as a sphere moving through the mask’s pore [2]. Its motion is influenced by convection in the carrier fluid, by diffusion, and by short-range interactions with the pore walls [2]. Interactions that trap the virus against the pore wall are the primary barrier to transmission [2]. This concept can be used for predicting transmission of the avian flu virus via eggshell. In this article the author analyzed the feasibility of avian flu virus passing through the N-95 mask by taking nanostructure level into consideration. The basic concept is that if the size of the virus is larger than the pore size of the N-95 mask, the virus cannot pass through the pores [2]. The author searched for the size of the virus and the pores of the N-95 mask in the literature. According to the search, the size of the pores of the N-95 mask is about 300-500 nm in diameter [5] and the size of the avian flu virus is about 100 nm (http://www.users.rcn.com/jkimball.ma.ultranet/BiologyPages/I/Influenza.html). Based on the particle size as a single factor, the pore size of the N-95 mask is about 3–5 times larger than the size of the virus. The author hereby proposes that the transmission on the avian flu virus through the N-95 mask is feasible. Indeed, the possibility that SARS, a virus of similar size to the avian flu, can pass through the N-95 mask has also been reported [4]. In addition, the N-95 mask also has about a 10% leakage problem around the mask [3]. It should also be noted that N-95 masks, at best, provide a seal with external leakage in the 3%–5% range. This assumes that the wearer of the mask has been properly fitted for the mask and is wearing the mask properly. The amount of inspired air that would bypass the filter and be brought around the filter and into the respiratory tract may be considerably larger. This is most apparent in individuals who are not wearing a mask correctly or who are not adequately trained in the proper fit of an N-95 mask. This is particularly problematic for family members and nonmedical personnel who may wish to use N-95 masks to prevent transmission of respiratory viruses. Therefore, there is no doubt about the possibility of the avian flu virus passing through the N-95 mask. However, transmission through the N-95 mask does not mean a person will be infected. There are many other factors that contribute to infection. In addition, influenza transmission generally occurs through small aerosol particles in the range of 1-10 μm in diameter. It is possible that individual virions are transmitted person to person, but most transmissions occur in small aggregates of viruses that would be effectively blocked by an N-95 mask. Using a mask does reduce the risk of infection compared with not using a mask. Also, the general universal precautions, especially washing the hands after contact with a person with respiratory infection, should be followed.

          Related collections

          Most cited references 5

          • Record: found
          • Abstract: found
          • Article: not found

          Laboratory performance evaluation of N95 filtering facepiece respirators, 1996.

            (1998)
          In 1995, CDC's National Institute for Occupational Safety and Health (NIOSH) introduced a new classification scheme for particulate air-purifying respirators. Most health-care workers use type N95 half-mask filtering facepiece respirators (i.e., N95 respirators) to prevent occupational transmission of tuberculosis. As a result, NIOSH received inquiries about how well N95 respirators fit, whether they need to be fit tested, and whether they can be quantitatively fit tested. In response to these inquiries, NIOSH evaluated the performance of 21 N95 respirator models on a 25-person panel. This report summarizes the results of this evaluation, which indicate that fit testing is needed to ensure at least the expected level of protection (i.e., the concentration of airborne contaminants inside the respirator is < or =10% of ambient levels).
            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            Performance of N95 respirators: Reaerosolization of bacteria and solid particles

              Bookmark
              • Record: found
              • Abstract: not found
              • Article: not found

              FDA researchers model virus transport through synthetic barriers

               P. DAVIS (1998)
                Bookmark

                Author and article information

                Contributors
                wviroj@yahoo.com
                Journal
                Lung
                Lung
                Lung
                Springer-Verlag (New York )
                0341-2040
                1432-1750
                3 November 2006
                2006
                : 184
                : 6
                : 373-374
                Affiliations
                GRID grid.7922.e, ISNI 0000000102447875, Department of Laboratory Medicine, Faculty of Medicine, , Chulalongkorn University, ; Bangkok, Thailand 10330
                Article
                21
                10.1007/s00408-006-0021-4
                7087815
                17086463
                © Springer Science+Business Media, Inc. 2006

                This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic.

                Categories
                Environmental & Occupational Lung Disease
                Custom metadata
                © Springer Science+Business Media, Inc. 2006

                Respiratory medicine

                influenza, avian influenza, pore wall, h5n1 virus, universal precaution

                Comments

                Comment on this article