Covid-19: AIIMS Delhi asks its staff to reuse N-95 masks four times

The hospital is yet to issue detailed guidelines on how to disinfect the said masks, according to the administration.

Despite rising coronavirus disease (Covid-19) cases among hospital staff in India, the country’s premiere medical college – the All India Institute of Medical Sciences (AIIMS), New Delhi – has asked its staff involved in direct patient care to use the five N-95 masks allotted to each of them four times so they can be used over 20 days, according to a hospital circular.

Even before the government has admitted a community spread, at least 34 healthcare workers have been infected in Delhi so far. (ANI / Photo used for representational purpose)

“It is imperative that in accordance with evidence-based scientific literature, these N-95 masks are to be disinfected by individual users (by keeping them in open after use or by other methods) and reused at least four times each, whereby these will suffice for about 20 days,” the circular reads.

The hospital is yet to issue detailed guidelines on how to disinfect the said masks, according to the administration.

“We have been writing to the administration about the shortage of personal protective equipment and N-95 masks since March. Not only have we not received any concrete answers on how they are dealing with the shortage, they have now issued guidelines for using the masks four times. How is a doctor supposed to carry the infected mask home? How are they individually supposed to disinfect it? This should happen at the hospital level to curtail the spread of the infection and even then only when there is no other option available,” said Dr Srinivas Rajkumar T, General Secretary of Resident Doctors’ Association at AIIMS.

Even before the government has admitted a community spread, at least 34 healthcare workers have been infected in Delhi so far. One of the doctors from the physiology department of AIIMS who tested positive for the infection and passed it on to his pregnant wife and brother was not involved in active care of Covid-19 patients; authorities have been unable to trace a clear history.

Around 20 other healthcare workers, who came in contact with a patient who later tested positive for Covid-19, have been quarantined for 14 days.

“The circular does not clarify whether the same will be applicable for people working in the Covid-19 wards and those screening the patients for respiratory symptoms – as they are at a higher risk of carrying the disease home with the masks. If we are at this stage even before the community transmission has begun, what will happen when there is a deluge of patients. This will take active doctors out of duty,” said Dr Srinivas.

The hospital insists that it is as per current scientific knowledge.

“We will shortly share the protocol for disinfecting the masks with everyone; N-95 masks do not need to be thrown away after one use,” said Dr DK Sharma, medical superintendent of the hospital.

In its guidelines on using personal protective equipment during Covid-19, the World Health Organization (WHO) says, “Respirators (like N-95 and FFP2) have been used for extended time during previous public health emergencies. This refers to wearing the same respirators while caring for multiple patients who have the same diagnosis. Evidence indicates respirators maintain their protection when used for extended periods. However, using one respirator for longer than four hours can lead to discomfort and should be avoided.”

The shifts of healthcare workers in the hospital last between eight and twelve hours. The WHO guidelines do not talk about reuse.

With the US scrambling to get supplies as their tally closes in on 370,000, their Centre for Disease Control has said a N-95 mask can be donned multiple times depending on manufacturer recommendation or up to five times, conditional to stringent measures on how the masks are stored and reused.

A group of researchers from Stanford University’s School of Medicine reviewed various decontamination measures and said hydrogen peroxide and ultraviolet radiation could disinfect the masks but they could not determine whether filtration and material strength would remain intact after repeated use.

Heating the mask at 70 degrees Celsius in kitchen microwave for 30 minutes or hot water vapour for 10 minutes can also help in decontamination, but the study came with the rider: “Please do not heat your masks in a home oven! Our reports do not advocate or advise on practices and suggest that you strictly adhere to your hospital’s policies and procedures.”