The Respiratory Shield is a lightbulb moment - one that re-invents the nasal cannula by adding a cover. It takes a thought so obvious - patients and nurses take nasal oxygen cannulas off more than you think - to its logical conclusion. People we love - people just like us - need a safe place to put their nasal cannula so that the prongs stay clean. 

Nasal prongs included in the study were swabbed.

In a MERS study, 16 fomites (stethoscopes, bag valve masks, blood pressure cuffs, nasal prongs, pillows, and keyboards) were swabbed and 13 tested positive for MERS-CoV. Furthermore, “It is worth noting that many environmental swab samples contained MERS-CoV despite daily cleaning and disinfection of the patients' rooms.” These findings are consistent with previous studies that demonstrated the survival of MERS-CoV for 2 days on plastic and steel surfaces. 

An article that explains the problem we are trying to solve.

“For patients switching to portable oxygen or home oxygen administration, nasal cannula storage can be problematic. The nasal cannula prongs often become contaminated when patients don’t properly protect the cannula between uses (i.e., leaving the nasal cannula on the floor, furniture, bed linens, etc.). Then the patient puts the contaminated nasal cannula back in their nostrils and directly transfers potentially pathogenic organisms from these surfaces onto the mucous membranes inside their nasal passages, putting them at risk of developing a respiratory infection.

Educate the patient on how to store the nasal cannula between uses in a manner that does not allow it to have direct contact with potentially contaminated surfaces,” Mary McGoldrick, MS, RN, CRNI, infection preventionist, consultant, and author.

COVID 19 and contact transmission.

“This mode of transmission has a tendency to get overlooked, but it may be incredibly important. 

This is how it works:

(i)  Someone with coronavirus coughs, emitting large droplets containing the virus. Droplets settle on surfaces in the room, creating a thin film of coronavirus.  The virus may be shed in nasal secretions as well, which could be transmitted to the environment.

(ii) The virus persists on fomites in the environment.  Human coronaviruses can survive on surfaces for up to about a week (Kampf et al 2020).  It's unknown how long COVID-19 can survive in the environment, but it might be even longer (some animal coronaviruses can survive for weeks).

(iii)  Someone else touches the contaminated surface hours or days later, transferring the virus to their hands.

(iv)  If the hands touch a mucous membrane (eyes, nose, or mouth), this may transmit the infection.

Any effort to limit the spread of the virus must block contact transmission.”

MERS (another type of coronavirus) can be spread through surfaces such as bedsheets, bedrails, IV fluid hangers, and X-ray devices up to 5 days after the last positive detection in respiratory specimens aka after the patients are recovered.


Full text: 

“Many environmental surfaces of MERS patient rooms, including points frequently touched by patients or healthcare workers, were contaminated by MERS-CoV. Viral RNA was detected up to five days from environmental surfaces following the last positive PCR from patients' respiratory specimens. MERS-CoV RNA was detected in samples from anterooms, medical devices, and air-ventilating equipment. In addition, MERS-CoV was isolated from environmental objects such as bedsheets, bedrails, IV fluid hangers, and X-ray devices." 


Most of the touchable surfaces in MERS units were contaminated by patients and health care workers and the viable virus could shed through respiratory secretion from clinically fully recovered patients. 

“In patients' rooms, bed sheets, bed rails, bed tables, bed controllers, shelves, door buttons, bathroom doorknobs, and floors were swabbed (Table 2). Patient care equipment such as patient monitor buttons, thermometers, IV fluid hangers, portable X-rays, and computed radiography cassettes were also swabbed.”

“The RT-PCR results with the environmental specimens revealed that bed controllers (5 of 15 specimens, 33.3%), IV fluid hangers (5 of 14 specimens, 35.7%), anteroom desks (3 of 7 specimens, 42.8%), and bedrails (4 of 15 specimens, 26.7%), were frequently positive (Table 3).”

“Infectious virus was also found in some environmental samples including those from bed sheets (room C), IV fluid hanger (room C), bedrail (room D), anteroom table (room D), and X-ray devices (room D) (Tables 2 and 3). It is noteworthy that the virus was recovered from the specimen taken from the IV fluid hanger in room C even on the day when the patient was negative for viral RNA as assessed by RT- PCR.”

“Our results clearly demonstrate that the unwitting actions by both patients and healthcare workers potentially induce viable virus contamination of the surface of various environments and medical devices (X-ray machines, thermometers) around MERS patients.”

Contaminated fomites or surfaces play a key role in the spread of viral infections.

“For centuries it was assumed that infectious diseases were spread primarily by the airborne route or through direct patient contact, and the surrounding environment played little or no role in disease transmission.

Up until 1987 the Centers for Disease Control and the American Hospital Association focused on patient diagnosis due to the belief that nosocomial infections were not related to microbial contamination of surfaces. Over the years studies have changed the perspective on viral transmission to include a more complex multifactorial model of disease spread. There is now growing evidence that contaminated fomites or surfaces play a key role in the spread of viral infections”...”Yet, fundamental knowledge concerning the role of surfaces and objects in viral disease transmission is lacking, and further investigation is needed.”

”During and after illness, viruses are shed in large numbers in body secretions, including blood, feces, urine, saliva, and nasal fluid.”  “If viruses remain viable on surfaces long enough to come in contact with a host, the virus may only need to be present in small numbers to infect the host... After contact with the host is achieved, viruses can gain entry into the host systems through portals of entry or contact with the mouth, nasopharynx, and eyes.” Currently, laboratory studies, epidemiological evidence, and disinfection intervention studies have generated strong indirect and circumstantial evidence that supports the involvement of fomites as a vehicle in respiratory and enteric virus transmission.” 

“A majority of respiratory viruses are enveloped (parainfluenza virus, influenza virus, RSV, and coronavirus) and survive on surfaces from hours to days.”

Coronavirus persists in an infectious state on common surface materials for several days.

“Surface contamination has recently been found to be more significant than originally thought in the spread of many diseases. Symptoms of respiratory disease often result in continuous recontamination of surfaces which are then touched, and infectious virus particles may be transferred to facial mucosa.”

Coronavirus persists in an infectious state on common surface materials for several days. The chart shows coronavirus persisting for five days on PVC. Nasal cannulas are made from PVC.

“There is scant information on minimum infectious doses, but for many respiratory viruses, the minimum infectious dose is believed to be low, i.e., just a few virus particles.”

”The results from this study have shown that a relatively low concentration of enveloped respiratory viruses may retain infectivity on common hard surfaces for longer than previously thought and may present a real risk of infection to anyone who contacts a contaminated surface.”

Nosocomial (hospital-acquired) spread of viral diseases in hospital outbreaks.

Viral spread in nursing homes

Dynamics of infectious disease transmission by inhalable respiratory droplets.

How dirty is your hospital bed? Do you really want to put your nasal cannula on it?

Can a hospital room ever be truly clean?

Influenza outbreaks