Rampant rise in deaths of healthcare workers (doctors and nurses) due to lack of respirators.
Healthcare workers’ lives are under severe stress in hospitals, families and friends. Children, spouses and friends show unknown fear of contracting coronavirus from healthcare workers due to nature of their job. Socially isolated healthcare workers feel depressed treating covid-19 patients without respirators.
More than 2561 healthcare workers have contracted coronavirus whilst treating Covid-19 patients. More than 1510 doctors have contracted coronavirus in last two months in 231 hospitals. More than 25 doctors have died and 8 are on ventilators. Five doctors died in one days at end of May 2020.
When a healthcare worker goes home after treating covid-19 patients, his/her parents, children and families look on them with fear in hearts and eyes. Healthcare workers take bath, change clothes and shoes before meeting family members. They disinfect their clothes, shoes and bags. It is a daily rehearsal yet everyone around doubts fear of contracting coronavirus from them.
Doctors are dying without respirators, but executives, politicians and elite groups are wearing respirators. Rich people and executives should feel ashamed wearing respirators among people. TV hosts and officials should stop wearing respirators, and use medical masks instead of respirators.
Respirators (N95 or KN95) for healthcare workers, surgical/medical masks for surgeons/patients, dust masks and DIY type face coverings for general public. Respirators can be disinfected using IR heat, UV light and chemical cleansers. Mask quality depends on its filtering efficiency. Superior filtering capacity respirators cost $13 to $340. Surgical/medical face masks cost less than one dollar.
Viruses and bacteria come in 0.3 to 60 mm, radioactive fallout in 0.1 to 10 mm, pesticides/herbicides in 0.0001 mm and smoke particles in 0.1 to 50 mm. Dust particles come in 1 to 100 mm sizes, which settle on surfaces due to gravity. Oxygen gas molecules come in 0.000292 mm sizes which sustain life.
Healthcare workers wear respirators (N95, KN95 or FFP2 etc.) to protect themselves against infection and respiratory viruses. Covid-19 patients can wear medical masks to prevent the spread of infectious droplets to others. However, medical masks do not protect against infection with respiratory viruses. Healthy people need no mask in home and community settings. Dust susceptible persons can wear DIY dust masks as coronaviruses can ride over pollutants in air [Leonardo 2020].
Face masks come in three types to protect against nanoparticles (N100, FFP3), PM2.5mm fine particles, viruses and small respiratory droplets (N95, FFP2, KN95) and large respiratory droplets and PM10mm haze particles (FFP1, dust masks) in USA, Europe and China. Equivalent standard masks for fine particles, viruses and small droplets in Australia/New Zealand, Japan and Korea are P2, DS and Korea 1st class respectively. N95 and KN95 respirators use salt as test agent at 85 L/min flow rate at inhalation/exhalation pressures of £ 343/350 Pa and £ 245/250 Pa. N95 and KN95 have ³ 95% efficiencies compared to others (³94%). Respirators are tight fitting devices and surgical/medical or DIY face masks loose fitting devices.
N95 respirators and surgical masks are worn by healthcare workers. These masks provide protection against viruses and bacteria, not against chemical odors, gases or vapors [Thomas 2020]. N95 respirators remove more than 95% airborne particles of ³ 0.3mm size. Surgical or medical masks are worn by health professionals during surgery and during nursing to catch the bacteria shed in liquid droplets and aerosols from the wearer's mouth and nose.
In order to remove chemical gases from the air the respirator must have absorbent or adsorbent media, or catalyst in the filter. Absorption occurs when a gas or vapor penetrates a solid structure (like charcoal) and gets “trapped” in the constituent molecules, atoms and ions of the structure. Gas molecules range in size from only 0.0003 - 0.006mm, which like chlorine, hydrogen sulfide and ammonia can freely pass through tiny spaces between the fibers of N95 mask. Use of N95 respirator to reduce the impact of a chemical gas exposure is comparable to the use of a placebo in patient care. However, N95 is excellent respirator against bacteria and viruses.
N95 mask equivalent in Europe and China are called FFP2 and KN95 respirators. China supplies 50% of respirators, therefore, Covid-19 outbreak in China created shortage of N95 masks worldwide. N95 mask or respirator shortage became panic when some executives in developing countries started wearing N95 respirators to protect themselves against Covid-19 disease [Lily 2020]. N95 masks are made of polyester and other synthetic fibers, including layers of tangled fibers that act as a filter. N95 masks with valves can infect others with wearer’s breathe out.
N95 masks requires a fine mesh of synthetic polymer fibers. These masks are produced through a melt blowing process to form inner filtration layer to remove hazardous particles. N95 masks are used single time in general, however, during shortage five times if not contaminated by patient blood. CDC, is considering to disinfect N95 masks UV germicidal irradiation, vaporous hydrogen peroxide (VHO) and moist heat methods. If there is no shortage of N95 masks then single use is recommended [CDC, 2020].
UV (260-285nm) light needs 30 [Fischer 2020] to 60 [Standard 2020] minutes exposure. VHP needs hardly 10 minute and dry heat sterilization requires 60 minutes of heating at 70°C or 15 minutes at 121°C using autoclave. SARS-CoV2 viruses die after 72 hour on inanimate materials therefore for masks may be used in cyclic manner. Ethanol bath followed by drying decontaminates in 10 minutes [Anand 2020].
Personal protective equipment (PPE) is protective clothing, goggles, gowns, gloves, masks, or equipment designed to protect the wearer's body from injury or infection. The hazards addressed by protective equipment include physical, electrical, heat, chemicals, biohazards, and airborne particulate matter. N95 masks were originally developed for mining workers for protection against nanoparticles.
Letters N, R and P refer to non-oil resistant, oil resistant and oil proof masks. RN95 for healthcare workers and R95 for industry people. You also see N99 or N100 and P99 or P100 respirators which are designed to filter even smaller particles but it is hard to breathe through higher number filters. First layer blocks PM10, second layer PM2.5 to PM0.3 particles and third layer blocks viruses, bacteria and gas pollutants. N100 is generally recommended for foundry, grinding, mineral processing and welding applications. Higher the number, harder to breathe. Three layer masks for military applications.
However, a surgical mask is a loose-fitting disposable filter that creates a physical barrier between the mouth and nose of the wearer and contaminants in the environment around him/her. If worn properly, a surgical mask is meant to help block large-particle droplets, splashes, sprays, or splatter release from wearer that may contain viruses and bacteria. Surgical masks basically help reduce exposure of the wearer's saliva and respiratory secretions to others. Medical masks filter 60 to 80% particles. Medical masks are made of paper like synthetic fabric.
A healthy person needs no mask. However, air pollution (smog) is another issue like pollen in spring that may require susceptible people to wear appropriate masks dust, molds and allergens. Air pollution has become a serious concern in China and India where air quality index (AQI) rises several times higher than the safety limits. AQI in China, India and Italy plummeted well below limits during Covid-19. A scholar said during Covid-19 outbreak lockdown the nature has closed atmosphere for repair. If medical masks are in short supply you can wear homemade cotton fabric masks.
Air pollution is higher throughout the year in India and China yet smog peaks during paddy crop harvest days when farmers burn stubble to prepare land for wheat crop. Smog has become fifth season in India where Delhi looks like a gas chamber. India is sleep walking into runaway environmental catastrophe by deadly combination of fossil fuels emitted smog and fascism. N95 masks filter fine particles too. A filter is a device that separates undesired pollutants. Filter is a general term used in physics, chemistry and engineering. Physicists use filters to block certain color lights, acousticians use to block noise, chemists use to separate solutes from solvents, and electronic engineers use to block noise. Mechanical engineers use filters to block dust particles entering into engine. Biologists and doctors recommend using filters and masks to prevent entry of airborne particles into mouth and nose.
Principle of filters or masks is to use single or multiple layers of barrier such as cloth, paper or synthetic materials which block airborne contaminants and allow air to pass into mouth and nose. The key tactic is to choose a porous barrier material in which size of mesh is smaller than desired particles intended to be blocked. Typical sizes of particles and viruses are shown below
Airborne particles, bacteria and viruses sizes (in mm) [Mieszko, 2016]
Smart Air conducted an interesting study to determine 1mm size particle blocking efficiency of various materials used in filters and face masks. A laser particle counter was used to count particles passing through various filter and mask materials. This research found 3M N95 masks block more than 99.99% airborne particles. HIPA and HERO filters block 99% and 98% airborne particles. However, paper towel, canvas and cotton sheets capture 90% particles.
Smart air conditioning systems for asthma and allergy patients from different manufacturers are available market. Natural environment does not suit to everybody. To have living and working spaces free from allergens and pollutants, we have to manage. However, healthy people can live in harmony with nature. Air pollution standards put limits on PM10 and PM2.5 particles. Airborne particles vary in size from nanometers (nm) to micrometers (mm). The sizes of smallpox and Ebola viruses are 0.3 and 1 mm. Microscopic organisms and particles range from a few mm to nm sizes.
Types of airborne atmospheric particles include suspended particulate matter, thoracic and respirable particle, inhalable coarse particles, which are coarse particles with a diameter between 2.5 and 10μm (PM10), fine particles with a diameter of 2.5μm or less (PM2.5), ultrafine particles, and soot.
According to Cambridge Mask Company, “on average, we humans take about 16 breaths a minute, 960 breaths an hour, 23 040 breaths a day and 8 409 600 a year. If you’re lucky enough to live to the ripe old age of 80, you’ll take approximately 672 768 000 breaths in your lifetime!” Suppose one breath takes 1mg PM 2.5 particulates into your lungs then at end of life a total mass of 672 grams accumulates in the lungs. However, lungs defense system continues to push them back yet some reach into blood.
We know rats can pass through steal fence walls, but cats cannot. Sand, silt and clay particles vary from 0.05 to 2mm, 0.002 to 0.05mm and < 0.002mm sizes. Bacteria sizes vary from 0.02 to 0.42mm whereas viruses vary in size from 0.02 to 0.4mm. Viruses and bacteria are so small that they can easily pass through ordinary filters. E coli, E. faecalis and C. jejune are rod shaped bacteria that come in 2´0.5mm, 1´1mm and 3-5´0.5mm sizes. Rod shaped bacteria come in 1-10mm´0.25-1mm sizes. They may pass widthwise, but not widthwise. Materials may have mesh sizes of 0.2-0.8nm and viruses 0.02-0.4mm.
Red blood cell size is 7mm whereas diameter of SARS-CoV2 virus is 0.125mm (0.06 to 0.14mm). However, size of the SARS-CoV2 virus droplets sneezed by patient may vary from 5-10mm. However, wool scarf, polyester neck warmer, cotton bandana and light scarf have poor filtering capabilities. Cashmere and light ramie have 43% and 24% filtering efficiencies. Denim, bed sheet and paper towels have higher efficiencies. All mask filters are desired to block 99.95% to 99.97% of 0.3mm particles.
A surgical mask blocks 80% large size airborne particles, but not nanoparticles. It may be good against pollen and air pollution yet not against Covid-19 viruses. However, these can block waterborne viruses and bacteria coming out of mouth into environment. It is not safe to visit Covid-19 patients using ordinary surgical masks. N95, FFP2 and KN95 masks can block viruses that are in use by healthcare workers.
Masks prices went up during peak of Covid-19 outbreak, however, later prices of KN95, FFFP2 and N95 respirators face masks were $3.00, $2.5 and $4.25 respectively. Prices vary place to place depending upon demand and supply. China has flooded market after 76 days lockdown.
Government scientists say sunlight, heat and humidity may have a “powerful” impact on killing the coronavirus within one or even two minutes. However, warns against using ultraviolet light to disinfect your body, saying UV radiation can cause skin irritation. Health experts advise people to use bleaches to disinfect surfaces, not to drink bleach or isopropyl alcohol to kill COVID-19. Trump’s idea to disinfect lungs leaves medical experts aghast.
US officials and some scientists claim light, heat and humidity can kill coronavirus [Cecelia 2020]. Lesser spread of Covid-19 in Far East compared to China, Europe and America is quoted as reference. Scientific insights from laboratory studies predicts that COVID-19 would ease over summer with heat, humidity, and UV light [Cory 2020]. Humidity rises in summer (70-80%] and falls during winter (24%) months. Winter viruses feel stable at 20-50% relative humidity [Miyu 2020].
SARS-CoV-2 transmission occurs through contact (direct & indirect), droplet spray in short range and aerosols in long-range (airborne transmission). The respiratory droplets spread up to 6 feet when infected person coughs, sneezes or talks. LiveScience, experts advise to increase mutual distance more than six feet. Larger respiratory droplets (>5mm) travel less than 1 meter and remain in air only for short time [Lu 2020]. However virus-laden small (<5mm) aerosolized droplets can travel longer distance (>1m) and remain in air for longer time [Fernstoorm 2013].
Wind currents may transfer dust particle born viruses to distant places [Pica, 2012]. Air conditioner flow may mediate local distribution of viruses in close rooms. Temperature and humidity modulate virus surface proteins and lipid membrane. Relative humidity has significant effect on airborne transmission [Miyu 2020]. Fast fans, air coolers and air conditioners in summer may affect spread rates.
WHO refers to large respiratory droplets (>5-10mm) as droplet particles and small respiratory droplets (<5mm) as droplet nuclei. Covid-19 is transmitted through respiratory droplets and contacts. Airborne droplet nuclei remain in air for long time so travel over longer distances [WHO 2014]. A recent report claims the SARS-CoV-2 aerosol may travel up to 4m distance that makes is very dangerous for hospital settings [Guo 2020]. Aerosols are produced in hospital during several procedures and treatments like endotracheal intubation, bronchoscopy, open suctioning, administration of nebulized treatment, manual ventilation before intubation, turning the patient to the prone position, disconnecting the patient from the ventilator, non-invasive positive-pressure ventilation, tracheostomy, and cardiopulmonary resuscitation etc. [WHO 2020].
Viruses can stay viable in air for three hours [Editor 2020]. However, this result is based on laboratory experiment that has little similarity with cough or sneeze conditions. Primary mode of transmission is touch with contaminated surfaces, and then with mouth, nose and eyes. Infected person’s viruses can stay on computer mouse, trash cans, sickbed handrails, door knobs, exercise equipment, medical equipment, PC, iPads, reading classes, cellular phones, remote controls, toilets, room surfaces, bedside tables, rails, and window ledges. Virus stays on plastics and stainless steel up to 2-3 days, on cardboard up to 1 day and copper up to 4 hours [Guo 2020]. Floor swab samples are positive as gravity causes respiratory droplets float to earth. Walking healthcare workers spread by shoes to all around. For doctors and paramedics, it is very important to disinfect shoes at exit. Viruses enter into soles of shoes that become carriers. Healthcare workers have to be more conscious than others.
Healthcare workers wear N95, KN95 and FFP2 face masks to protect themselves against infection and respiratory viruses. Covid-19 patients must wear medical masks to protect others from their own infectious droplets. Everybody can wear medical and DIY masks outside home.
Never forget to change or disinfect masks everyday.
References
Leonardo S, Fabrizio P, Gianluigi DG, Pierluigi B, Maria GP, Massimo B, Jolanda P, Alessia DG, Valentina T, Alberto P, Maurizio R, Prisco P, Alessandro M, SARS-Cov-2 RNA Found on Particulate Matter of Bergamo in Northern Italy: First Preliminary Evidence, Letter to Editor, BMJ, 18 April 2020. https://doi.org/10.1101/2020.04.15.20065995.
Thomas PF, N95 respirators and toxic gases or vapors, Massachusetts Nurse Newsletter, 15 September 2008. https://www.massnurses.org/health-and-safety/articles/chemical-exposures/p/openItem/1318
Lily K, Fury in China as footage appears to show officials taking doctors' face masks, The Guardian, 5 February 2020. https://www.theguardian.com/world/2020/feb/02/shameless-outrage-china-coronavirus-outbreak-mask
Dawn, 'Was reusing N-95 mask given to me in China': President Alvi responds to criticism, Dawn, 9 April 2020. https://www.dawn.com/news/1547737
CDC, "Decontamination and Reuse of Filtering Facepiece Respirators". U.S. Centers for Disease Control and Prevention. 2020-04-09. Retrieved 2020-04-20
Fischer RJ et al. Assessment of N95 respiratory decontamination and re-use for SARS-CoV-2. Preprint without peer review 04.15.20. [Link is HERE]
Stanford Medicine: Addressing COVID-19 Face Mask Shortages
Anand S, "N95 Mask Decontamination and Reuse", REBEL EM blog, April 21, 2020. Available at: https://rebelem.com/n95-mask-decontamination-and-reuse/.
Paddy R, What Are The Best Materials for Making DIY Masks? Smart Air, 8 March 2020. https://smartairfilters.com/en/blog/best-materials-make-diy-face-mask-virus/
Paddy R, The Ultimate Guide to Homemade Face Masks for Coronavirus, Air Smart, 21 April 2020. https://smartairfilters.com/en/blog/best-diy-coronavirus-homemade-mask-material-covid/
Mieszko J, https://commons.wikimedia.org/wiki/File:Airborne-particulate-size-chart_fr_particules.jpg, 3 January 2016
Cecelia SS, U.S. Official: Sunlight, Heat, Humidity Could Help Kill Coronavirus, US News, 23 April 2020. https://www.usnews.com/news/national-news/articles/2020-04-23/us-official-sunlight-heat-humidity-could-help-kill-coronavirus
Cory M, Mark CU, Seasonality and uncertainty in COVID-19 growth rates, BMJ, 22 April 2020. doi: https://doi.org/10.1101/2020.04.19.20071951
Miyu M, Walter J, Akiko I, Seasonality of Respiratory Viral Infections, Annual Review of Virology, 7:2.1–2.19, 2020. https://www.annualreviews.org/doi/pdf/10.1146/annurev-virology-012420-022445
Lu J, Gu J, Li K, Xu C, Su W, Lai Z, et al. COVID-19 outbreak associated with air conditioning in restaurant, Guangzhou, China, 2020. Emerg Infect Dis. July 2020. https://doi.org/10.3201/eid2607.200764
Fernstrom A1, Goldblatt M. Aerobiology and its role in the transmission of infectious diseases. J Pathog. 2013;2013:493960. doi: 10.1155/2013/493960. Epub 2013 Jan 13.
Pica N1, Bouvier NM.Environmental factors affecting the transmission of respiratory viruses. Curr Opin Virol. 2012 Feb;2(1):90-5. doi: 10.1016/j.coviro.2011.12.003. Epub 2012 Jan 4.
WHO, Infection prevention and control of epidemic- and pandemic-prone acute respiratory infections in health care, WHO Guidelines 2014.
Guo Z-D, Wang Z-Y, Zhang S-F, Li X, Li L, Li C, et al. Aerosol and surface distribution of severe acute respiratory syndrome coronavirus 2 in hospital wards, Wuhan, China, 2020. Emerg Infect Dis. 26. July, 2020. https://doi.org/10.3201/eid2607.200885
WHO, Modes of transmission of virus causing COVID-19: implications for IPC precaution recommendations, Scientific Brief, 29 March 2020.
Editor, Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1, N Engl J Med 2020; 382:1564-1567, DOI: 10.1056/NEJMc2004973
