A nurse is caring for a patient with suspected Lassa fever in the isolation unit. Which action demonstrates the most critical aspect of personal protective equipment (PPE) usage in this high-risk situation?

Following a strict donning and doffing sequence with a trained observer is critical for Ebola to prevent contamination during removal.

Critical Aspect of PPE for Viral Hemorrhagic Fevers

When managing a patient with a suspected viral hemorrhagic fever (VHF) such as Lassa fever, all the listed options represent important components of infection prevention and control (IPC). However, the question asks for the most critical action, which shifts the focus from the type of equipment to the process of using it. The correct answer is following the strict sequence for donning and doffing PPE with a trained observer present.

The rationale is rooted in the fact that the highest risk of healthcare worker (HCW) contamination occurs not during patient care while fully protected, but during the removal (doffing) of contaminated PPE. A Cochrane review on PPE for highly infectious diseases found that the doffing process is a primary point of failure, where HCWs can inadvertently self-contaminate by touching soiled outer surfaces and then their skin or mucous membranes ^[4]. This is particularly true for VHFs like Lassa fever, where transmission occurs through direct contact with infected body fluids.

A trained observer serves as a cognitive aid and safety net during this high-stakes procedure. By following a strict, step-by-step sequence verified by the observer, deviations are immediately corrected before a breach occurs. The importance of this structured, supervised approach was clearly demonstrated during the management of the first imported case of Lassa fever in China, where strict IPC measures, including supervised donning and doffing, were a cornerstone of the response that successfully prevented any secondary transmission ^[1]. The observer ensures that the sequence—designed to remove the most contaminated items first—is meticulously followed, mitigating the risk of contact transfer.

While the other options are valuable IPC practices, they are components of a larger system and do not independently address the highest-risk moment of care.

- Option 2 (Double gloving): Wearing double gloves is a specific recommendation for VHF care because it allows the outer, heavily contaminated glove to be removed first during doffing, reducing hand contamination risk ^[2]. However, this is a single element within the doffing sequence; its protective value is lost if the sequence itself is flawed.

- Option 3 (N95 respirator): An N95 respirator is essential for airborne precautions but Lassa fever is not transmitted via the airborne route. Its primary mode of transmission is direct contact with blood and body fluids, though droplet transmission is possible during aerosol-generating procedures. A surgical mask would be insufficient for droplet protection, but the choice of respiratory protection is not the most critical procedural step that prevents the majority of self-contamination events.

- Option 4 (Complete skin coverage): Ensuring PPE covers all exposed skin is a fundamental principle of barrier protection. Evaluations of Lassa fever treatment centers in Nigeria have identified incomplete skin coverage as a breach in IPC practice . However, even perfectly applied PPE that provides complete coverage becomes a vector for contamination if removed improperly. The integrity of the barrier is only as good as the technique used to take it down.

In essence, the most meticulously chosen and worn PPE ensemble can be rendered ineffective by a single error during removal. The strict, observed donning and doffing sequence is the overarching safety system that controls the highest-risk procedure, making it the most critical action for preventing HCW infection with Lassa fever [1,4].