The World Health Organization (WHO) has recently released updated guidance on occupational health and safety for health workers.

Background information:

The new guidance document updates the interim guidance issued by the WHO on 18 March 2020.

The guidance was developed based on a review of existing WHO and International Labour Organization (ILO) guidance documents, rapid reviews of evidence about occupational risks that have been amplified by the COVID-19 pandemic and expert opinion from an international group of experts.

In the context of COVID-19 health workers may be exposed to occupational hazards that put them at risk of disease, injury and even death. These risks include:

• Occupational infections with COVID-19
• Skin disorders and heat stress from prolonged use of PPE
• Exposures to toxins because of increased use of disinfectants
• Psychological distress
• Chronic fatigue, and
• Stigma, discrimination, physical and psychological violence and harassment.
• Insufficient occupational health and safety measures can cause
• Increased rates of work-related illness among health workers
• High rates of absenteeism
• Reduced productivity, and
• Diminished quality of care

Occupational exposure to SARS-CoV-2

SARS-CoV-2 mainly spreads between people when an infected person is in close contact with another person.

The virus can spread from an infected person’s mouth or nose in small liquid particles ranging from larger ‘respiratory droplets’ to smaller ‘aerosols’ when the person coughs, sneezes, breathes heavily or talks. Close range contacts can result in inhalation of, or inoculation with, the virus through the mouth, nose or eyes.

Aerosol transmission can occur in specific situations in which medical procedures that generate aerosols are performed. There is inconclusive evidence about aerosol transmission in health-care settings in the absence of aerosol generating procedures.

There is limited evidence of transmission through fomites (objects or materials that may be contaminated with viable virus, such as utensils, furniture, stethoscopes or thermometers) in the immediate environment around an infected person. Such transmission may occur through touching the fomites followed by touching the mouth, nose or eyes.

There is emerging evidence of transmission in settings outside of medical facilities, such as indoor, crowded, and inadequately ventilated spaces, where infected persons spend long periods of time with others. This suggests the possibility of aerosol transmission in addition to droplet and fomite transmission.

Key Messages:

Workplace risk assessment for SARS-CoV-2

The potential for health workers’ occupational exposure to SARS-CoV-2 can be determined by the likelihood of coming into direct, indirect or close contact with a person infected with the virus. This includes direct physical contact or care, contact with contaminated surfaces and objects, through aerosol-generating procedures on patients with COVID-19 without adequate personal protection, or working with infected people in indoor, crowded places with inadequate ventilation. The risk of occupational exposure increases with the level of community transmission of SARS-CoV-2.  

The following risk levels are suggested:

Lower risk: jobs or tasks without frequent, close contact with the public or others and that do not require contact with people known or suspected of being infected with SARS-CoV-2

Examples: Telehealth services, remote interviewing of suspected or confirmed COVID-19 patients

Medium risk: jobs or tasks with close frequent contact with patients, visitors, suppliers and co-workers but that do not require contact with people known or suspected of being infected with SARS-CoV-2

Examples:

• In settings with known or suspected community transmission of SARS-CoV-2

Workers who have frequent and close work-related contact with other people within a health-care facility or in the community where safe physical distance may be difficult to maintain.

• In settings without suspected community transmission of SARS-CoV-2

Close frequent contact with people coming from areas with known or suspected community transmission.

High risk: jobs or tasks with high potential for close contact with people who are known to be or suspected of being infected with SARS-CoV-2 or contact with objects and surfaces possibly contaminated with the virus

Examples:

• Clinical triage with in-person interviewing of patients with signs and symptoms of COVID-19
• Cleaning areas for screening and isolation
• Entering rooms or isolation areas occupied by known or suspected COVID-19 patients
• Conducting a physical examination and providing direct care not involving aerosol-generating procedures for known or suspected COVID-19 patients
• Manipulation/ handling of respiratory samples/ secretions
• Transportation of people known or suspected of having COVID-19 without physical separation between driver and passenger
• Cleaning between transports of patients with suspected COVID-19

Very high risk: jobs and tasks with risk of exposure to aerosols containing SARS-CoV-2, in settings where aerosol generating procedures are regularly performed on patients with COVID-19 or working with infected people in indoor, crowded places without adequate ventilation

Examples:

Work with COVID-19 patients where aerosol-generating procedures like

• Tracheal intubation
• Non-invasive ventilation
• Tracheostomy
• Cardiopulmonary resuscitation
• Manual ventilation before intubation
• Sputum induction
• Bronchoscopy
• Autopsy procedure
• Dental procedures that use spray-generating equipment

are frequently performed

Work with infected people in indoor, crowded places without adequate ventilation.

Prevention and mitigation measures by risk level

Risk level	Health facilities	Workers	Patients, visitors & suppliers
Lower risk	Organize remote work and teleservices wherever possible. Provide natural/mechanical ventilation without recirculation. Organize regular environmental clean-up and disinfection. Introduce measures for avoiding crowding. Introduce measures preventing the sharing of workstations and equipment	Stay home if unwell. Observe hand & respiratory hygiene. Use fabric masks in common areas and face-to-face meetings
Medium risk	Consider alternatives to face-to-face outpatient visits. Provide sneeze screens, barriers, workplace modifications. Organize screening and triage for early recognition of patients with suspected COVID-19 and rapid implementation of source control measures. Introduce measures to avoid crowding and social mixing, such as restricting visitors and designating areas where visitors are not allowed. Encourage workers to observe safe physical distancing when not wearing PPE (like in cafeteria and break rooms). Provide IPC training and PPE in sufficient quantity and quality	Wear medical masks and other PPE according to their tasks and apply standard precautions in providing patient care.	Observe hand and respiratory hygiene. In settings with community or cluster transmission, wear medical or fabric masks.
High risk	Provide enhanced ventilation without recirculation, with “clean to less clean” directional design for airflow	Use PPE based on transmission-based precautions (medical mask, gown, gloves, eye protection) and apply standard precautions in providing patient care.	Wear medical or fabric masks.
Very high risk	Provide mechanical ventilation with high efficiency particulate air (HEPA) filters without recirculation. Provide regular IPC training, and training in donning and doffing PPE.	Use PPE (respirator N95 or FFP2 or FFP3, gown, gloves, eye protection, apron) and apply standard precautions in providing patient care.

Some health workers may be at higher risk of developing severe COVID-19 illness because of older age, pre-existing medical conditions or pregnancy. Such workers should not be required to carry out tasks with medium, high or very high risk levels in accordance with WHO recommendations.

Prolonged use of PPE

PPE is intended to be used for short periods of time when the exposure to hazard cannot be avoided or otherwise controlled. In the context of COVID-19, heavy workload, patient flows, and shortages of PPE may require health workers to wear PPE for extended periods of time.

If a health worker has a latex allergy, use of non-latex or nitrile gloves is advised. Frequent application of moisturizing creams is a good practice to decrease hand irritation. Products containing petroleum can damage the integrity of latex gloves and should be avoided for skin care. Health workers with sustained rashes or inflammatory skin symptoms should be referred to medical care.

There is evidence that prolonged use of PPE for respiratory and eye protection (masks, respirators, and goggles) can also cause skin damage: itching, rash, acne, pressure injury, contact dermatitis, urticaria and aggravation of pre-existing skin diseases. To decrease the risk of skin damage, it is a good practice to provide health workers with properly fitted PPE, to avoid sustained friction or pressure on the same site; to apply moisturizers or gel before wearing facial protective equipment to lubricate and reduce friction between skin and masks or goggles; and to avoid using over-tight goggles, which can damage the skin and generate fogging.

Prolonged use of full PPE (gowns, masks, head coverings, coveralls) traps heat and sweat, limits evaporative cooling of the body and can lead to heat stress (heat rash, muscle cramps, fainting, exhaustion, breakdown of skeletal muscle and heat stroke). Coveralls, double layering of gowns, shoe protection, or hoods that cover the head and neck such as those used in the context of filovirus disease outbreaks (e.g. Ebola virus), are not required when caring for patients with COVID-19.

Useful Link:

Link to the related WHO document:

https://www.who.int/publications/i/item/WHO-2019-nCoV-HCW_advice-2021.1