Tag Archives: sneeze distance

Fostering environment where employees work sick costs more than it saves

Faced with the choice of working while sick or sitting out and not getting paid, most will work while sick. Pros and Cons of Sick Pay Schemes: Testing for Contagious Presenteeism and Shirking Behavior takes a look at the ramifications. Most organizations’ human resource policy is focused on short term goal. It is clearly that way with sick pay. While it might take some logistics wrangling, there generally are duties that can be accomplished at home. It is time to get smart and realize that working sick hurts business as well as the bottom line.

The spread of disease in a facility happens quickly, as noted in Office Germs: Viruses Spread Everywhere in Just Hours, Study Shows. Bacteria and viruses move through the water system, on the air, and are moved around a facility on shoes, hands and clothes. Dr Gerba’s study showing how quickly the bacteriophage MS-2 virus moved throughout and office was enlightening.

How long do nosocomial pathogens persist on inanimate surfaces? A systematic review shows that bugs can remain viable on surfaces for hours, even weeks.

Bugs (viruses, bacteria and fungi) all move through the air.  The CDC always talks about droplet precaution.  It contends that droplets fall out of the air to a surface within six feet of the patient. MIT showed droplets moving 6-8 meters through the air in Studying the Science of 100 Sneezes. High-speed video shows how far sneezes spread in The snot-spattered experiments that show how far sneezes really spread. Droplet nuclei can remain suspended in air for extended periods, according to ASHRAE.

Focusing on cleaning for health, hand hygiene and sub-micron air filtration is a must for a healthy environment.

Studies show CDC’s droplet precaution guidance might fall short

sneezeThe Center for Disease Control (CDC) has provided guidance on droplet precaution that might need to be reconsidered. In the cloud: How coughs and sneezes float farther than you think is a study that uncovers the way coughs and sneezes stay airborne for long distances. Discussed at MIT News, the study specifically “finds that droplets 100 micrometers — or millionths of a meter — in diameter travel five times farther than previously estimated, while droplets 10 micrometers in diameter travel 200 times farther. Droplets less than 50 micrometers in size can frequently remain airborne long enough to reach ceiling ventilation units.” The video at this link shows droplets moving 6-8 meters (20-26 feet), considerably farther than the 6 foot droplet precaution put forth by CDC.

Extensive Viable Middle East Respiratory Syndrome (MERS) Coronavirus Contamination in Air and Surrounding Environment in MERS Outbreak Units explored the possible contribution of contaminated hospital air and surfaces to MERS transmission by collecting air and swabbing environmental surfaces in 2 hospitals treating MERS-CoV patients. The study shows clearly droplet precaution isn’t working. The presence of MERS-CoV was confirmed by reverse transcription polymerase chain reaction (RT-PCR) of viral cultures of 4 of 7 air samples from 2 patients’ rooms, 1 patient’s restroom, and 1 common corridor. In addition, MERS-CoV was detected in 15 of 68 surface swabs by viral cultures. Immunofluorescence assay (IFA) on the cultures of the air and swab samples revealed the presence of MERS-CoV. EM images also revealed intact particles of MERS-CoV in viral cultures of the air and swab samples. The study concludes: These data provide experimental evidence for extensive viable MERS-CoV contamination of the air and surrounding materials in MERS outbreak units. Thus, our findings call for epidemiologic investigation of the possible scenarios for contact and airborne transmission, and raise concern regarding the adequacy of current infection control procedures.

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Sneeze droplets shown to travel farther than conventionally believed

sneezeThe snot-spattered experiments that show how far sneezes really spread. Mathematician Lydia Bourouiba uses high-speed video to break down the anatomy of sneezes and coughs — and to understand infectious disease. In this piece at Nature, Corie Lok writes: Bourouiba’s goal is to “ground epidemiology and public health in physics and mathematics. When trying to keep diseases from running rampant, she says, “we want to be giving recommendations that are based on science that has been tested in the lab”. In practical terms, such insights could lead to maps showing the contamination risks in the vicinity of infected people, protective equipment optimized to shield hospital workers from specific kinds of germs, and better predictions of how diseases move through a population.

Lok goes on to write: The video evidence (shown wonderfully at this link) contradicted conventional thinking about sneezes, which held that larger droplets would fall to the ground within 1–2 metres, and that only the smaller ones would stay aloft as airborne aerosols. Feeding her video evidence into her mathematical models, Bourouiba concluded that, thanks to the cloud dynamics, many of the larger droplets can travel up to 8 metres for a sneeze and 6 metres for a cough, depending on the environmental conditions, and stay suspended for up to 10 minutes — far enough and long enough to reach someone at the other end of a large room, not to mention the ceiling ventilation system. That conclusion has implications for health-care workers, says James Hughes, an infectious-disease epidemiologist at Emory University in Atlanta. If a disease is thought to be transmitted within 1–2 metres, workers might assume that they are safe beyond that zone. “I think maybe we need to be a little bit more circumspect about that,” he says.

Aerosolized bacteria come from many sources. When you look at particle size you can really see how disease spreads through the air and on to other surfaces. Combine all this with bacterial and viral shedding, and it is easy to see how standard cleaning practices cannot keep up with the contamination levels.

In the cloud: How coughs and sneezes float farther than you think debunks Centers for Disease Control data droplet precaution that is set at 6 feet. As science advances, we have to rethink continually.

A High-Speed Super Zoomed Video Of What Happens To A Toilet When You Flush: You think you’re cleaning up the mess, but it’s just making it worse. That’s very bad in places where they’re trying to have no messes at all—like, say, a hospital. Aerosolized bacteria come from many sources.  When you look at particle size you can really see how disease spreads through the air and on to other surfaces. Combine all this with bacterial and viral shedding it is easy to see how standard cleaning practices cannot keep up with the contamination levels.