Are masks really necessary for routine care of TB patients?

Here two nurses make their case for and against.

TB specialist nurse Kelvin Karim argues in favour

The use of masks and respirators in caring for people with actual or suspected infectious TB has long been one of a number of infection control measures aimed at limiting its transmission.

Clearly, the risk of transmission will be greater in environments where aerosol generating procedures are being performed. However, to suggest - as the NICE guidelines do - that masks should be used only in the context of multiple-drug resistant (MDR) tuberculosis is illogical.

The first major question it raises is: why is it permissible to allow exposure to drug sensitive tuberculosis? It may well be because drug sensitive TB is treatable, while MDR TB is regarded as more serious. Given that MDR TB is no more or no less infectious than drug sensitive TB, and that tuberculosis adversely affects health - even if only temporarily - the question has to be asked: should we not wear respirators to help prevent unnecessary exposure from all patients with actual or suspected infectious tuberculosis?

Put another way, in the absence of evidence to support the current opinion-based NICE guidelines, should we not err on the side of caution, until more robust evidence becomes available?

Health protection nurse, Gary Porter-Jones puts the case against.

Nursing and medicine have long endeavoured to ensure that practice is founded on a firm evidence-base. Indeed, we find security in the knowledge that our resulting practice has undergone the scrutiny that ritualistic practices have not.

Why then, do we continue to recommend that staff use masks for routine care of patients with TB? This practice is not founded on scientific evidence and surely belongs in the realms of ritual. At best, it stems from the opinions of leaders in the field of TB, but this is quite different from recommendations that result from well-designed robust studies at the apex of a well-established hierarchy of evidence.

For example, current NICE guidance makes illogical, opinion-based, recommendations about mask use: don a high-filtration respirator if you think the patient has multidrug-resistant TB (MDRTB), but no need to use any mask if it's unlikely that the patient's TB is drug-resistant. What's the evidence that supports this approach? There is no evidence, scientific or otherwise, that MDRTB is more likely to be filtered out by a mask than its drug sensitive brother. Such irrational recommendations serve only to confuse clinicians about the rationale for their actions. This confusion is compounded by NICE's acknowledgment that there is conflicting guidance on whether staff should wear masks and their concern that the inappropriate use of masks worries patients. Of course it does - there is no evidence for their use and therefore they are likely to be used inconsistently.

Outside of performing high-risk procedures - such as those that generate aerosols from infectious patients - the use of masks in the routine care of people with TB must be reconsidered. It is well established that other interventions are far more effective in preventing transmission of TB. Early diagnosis of infectious cases, early treatment initiation, and early isolation measures are the key to effective TB control. Perhaps we should target our limited resources towards these and stop being distracted by mask use until the evidence dictates otherwise.