|Year : 2020 | Volume
| Issue : 1 | Page : 56-58
Personal-protective equipment priority list for developing countries in relation to the COVID-19 pandemic
Sanjay Bhattacharya1, Vinitha Mary Joy1, Priyanka Vivek2
1 Department of Microbiology, Tata Medical Centre, Kolkata, West Bengal, India
2 Department of Staff Health, Tata Medical Centre, Kolkata, West Bengal, India
|Date of Submission||15-May-2020|
|Date of Acceptance||28-May-2020|
|Date of Web Publication||13-Aug-2020|
Dr. Sanjay Bhattacharya
Department of Microbiology, Tata Medical Center, New Town, Kolkata, West Bengal
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Bhattacharya S, Joy VM, Vivek P. Personal-protective equipment priority list for developing countries in relation to the COVID-19 pandemic. J Acad Clin Microbiol 2020;22:56-8
|How to cite this URL:|
Bhattacharya S, Joy VM, Vivek P. Personal-protective equipment priority list for developing countries in relation to the COVID-19 pandemic. J Acad Clin Microbiol [serial online] 2020 [cited 2021 Jan 20];22:56-8. Available from: https://www.jacmjournal.org/text.asp?2020/22/1/56/291897
Respiratory droplet precautions form an essential component of preventing infections due to COVID-19. The World Health Organisation states that when the droplet particles are >5–10 μm in diameter, they are referred to as respiratory droplets, and when they are < 5 μm in diameter, they are referred to as droplet nuclei. According to the current evidence, COVID-19 virus is primarily transmitted between people through respiratory droplets and contact routes. The airborne transmission of SARS-CoV-2 was not seen in an analysis of over 70,000 cases reported from China.
In a study from the USA, it was reported that N95 masks made by different manufacturers had different filtration efficiencies between the particle sizes of 0.1–0.3 μ, but all were at least 95% efficient at that size for NaCl (sodium chloride) particles. Above these particles size, the filtration efficiency increased with size; it reached approximately 99.5% or higher at about 0.75 μ. In contrast, the pore size of cloth masks ranged from 80 to 500 μm. The PM10(particulate matter of diameter 2.5–10 μ) filtering efficiency of the cloth masks ranged from 63% to 84%. Compared to cloth masks, surgical masks (2 layered or 3 layered) had the complicated networks of fibres and much smaller pores in multiple layers, and therefore, had better filtering efficiency (more than 90%).
Personal protective equipment (PPEs) are devices and consumables used in the health-care setting for the prevention of infection in health-care workers (HCWs) and prevention of the transmission of pathogens to vulnerable patients. The Covid-19 pandemic has led to an unprecedented global, national and local shortage of PPEs. The commonly used PPEs till recent times were the three layer surgical masks and gloves (sterile and non-sterile); however, this list of essential and desirable PPEs has expanded during this pandemic to include N95 masks, eye protective devices such as goggles, splash protective devices such as face shields or visors, full-sleeved impervious gowns, plastic aprons, cap and shoe covers.
Depending on the transmissibility of a pathogen (R0 number), modes of transmission, routes of entry, pathogenicity, morbidity and case-fatality rate as well as biohazard group of the pathogen, various PPEs are used in different clinical situations and microbiology laboratories. The appropriate use of PPE is essential to optimise consumption, minimise waste and prevent stockpiling and redundancy [Figure 1] and [Table 1].
- Appropriate PPE in a non-AGP: Situation: N95 mask + face shield/goggles
- Appropriate PPE in an AGP situation: N95 mask + face shield/goggles/plastic apron + gown + cap
- Proper donning and doffing of PPE is as important as PPE quality and type in infection prevention
- AGP: Aerosol-generating procedures > Examples: Endotracheal/nasotracheal intubation, airway suctioning, tracheostomy, nebulisation and BIPAP ventilation
It is important for the HCWs, health-care administrators, stakeholders (e.g., manufacturers and developers) and donors to be sensitised regarding PPE priority listings, with respect to the specific pathogens or infections causing infectious disease outbreaks.
For example, in the ongoing Covid-19 outbreak, a priority list of PPEs could be as follows, in the descending order of importance.
- N 95 mask
- 3 ply surgical mask
- Eye-protective goggles
- Splash-protective devices such as face shields and visors
- Full-sleeved impervious gown
- Plastic aprons
- Shoe covers/gum boots.
This order may be justified by the given scientific hypotheses.
- SARS-CoV-2 and other respiratory viruses are transmitted by the droplets and occasionally through aerosols-containing infective particles (which are generated during nebulisation, Bipap ventilation, and endotracheal/nasotracheal intubation, airway suctioning and tracheostomy)
- Routes of entry for SARS-CoV-2 are through the nose, mouth and eyes; they are not known to enter through skin so far
- The presence of virus in non-respiratory fluids and/or tissues may be theoretically possible, but not common in the clinical situations 
- Droplets and aerosols landing on fomites (fabrics and other items surrounding patient) dry up quickly and are not the main sources of transmission.
PPEs are an expensive consumable, and we are seeing a massive surge in its price along with a decline in its availability during this outbreak. An example of a pricelist of commonly used PPE is displayed [Table 2].
|Table 2: Relative price of PPE: (from least expensive to most expensive)|
Click here to view
Concentrating on the lesser important PPE would not only divert invaluable resources unnecessarily, but also endanger staff and patient safety. The relative price of PPE is an important lesson in the dynamics of global economy during health-related emergency. For example:
- The price of one N95 mask is equivalent to the price of 15 3-ply surgical mask and 100 non-sterile gloves
- A single pair of long-shoe covers costs the same as 10 non-sterile gloves
- The cost of a face shield is more than the twice that of a pair of goggles
- One full-sleeved impervious gown will equal in price to almost 10 plastic aprons
- A single surgical cap or shoe cover is almost equal to or slightly more than a pair of non-sterile gloves.,
Therefore, in countries where health-care resources are limited, prioritisation of PPE into essential and desirable categories is paramount. Failure to do so will hinder our ability to overcome this latest health emergency.
| References|| |
Qian Y, Wileke K, Grinshpun SA, Donnelly J, Coffey CC. Performance of N95 respirators: Filtration efficiency for airborne microbial and inert particles. Am Indian Hyg Assoc J 1998;59:2.
Neupane BB, Mainali S, Sharma A, Giri B. Optical microscopic study of surface morphology and filtering efficiency of face masks. PeerJ 2019;7:s.l.
van Doremalen N, Bushmaker T, Morris DH, Holbrook MG, Gamble A, Williamson BN, et al
. Aerosol and surface stability of SARS-CoV-2 as compared with SARS-CoV-1. N
Engl J Med 2020;382:1564-7.
Diaz D, Sands G, Alesci C. Protective Equipment Costs Increase Over 1,000% Amid Competition and Surge in Demand. New York: CNN; 2020.
Incidents, Institute of Medicine (US) Committee on R&D Needs for Improving Civilian Medical Response to Chemical and Biological Terrorism. Institute of Medicine (US) Committee on R&D Needs for Improving Civilian Medical Response to Chemical and Biological Terrorism Incidents. Na. Chemical and Biological Terrorism: Research and Development to Improve Civilian Medical Response. Washington (DC): National Academies Press; 1999.
[Table 1], [Table 2]