Occupational physicians engaged in surveillance
evaluations such as audiometry and spirometry should be as concerned with the development of variant strains or COVID-19 as any clinician. Some variations in the SARS-CoV-2 virus have minimal importance. However, some others have more significant clinical effects:
Thus far, the emerging strains have primarily been associated with increased transmissibility (B. 1.1.7 from the United Kingdom, 1.351 from South Africa and P.1 in Brazil).1
- Changes in species specificity
- Increased virulence for causing serious disease
- Increased susceptibility/transmissibility
- Reduced effectiveness of current vaccines
- Changes in patterns of host susceptibility.
Of these, spread of B.1.1.7 is of most current concern in the United States and Canada as it has been shown to be 75% more transmissible.2
Cases have been identified in more than half of US states and will likely continue to be identified in additional states. Some data suggests that this variant is associated with increased mortality.3
To our knowledge, the strains with increased transmissibility
led to changes in regulatory requirements. However, clinicians should monitor OSHA, CDC, and state/county websites for any updates. In addition, since the process of mutation is on-going, new variations will continue to arise. Clinicians should monitor for reports of increased severity of illness or, changes in population group/subgroup susceptibility, or effectiveness of vaccine induced antibody.
Despite the absence of regulatory changes, emergence of variants with increased transmissibility warrants reiterating current principles and regulations. Key elements include the following:
- Adjust local surveillance practices based upon local and state rates. OSHA policies permit deferring some testing if based upon "good faith efforts". Therefore, even if testing has resumed, an increase in local or state rates may warrant reinstitution of deferring some testing. Local/regional factors to consider include the incidence of new cases, percent of tests that are positive, hospitalizations, and availability of critical care services if needed.
- Exposure control measures should not be relaxed. The availability of vaccines should not lead to slackening of these measures until herd immunity has been achieved and community transmission is well controlled.
- As previously, the decision to test an individual patient depends upon the importance of the procedure. For example, routine annual testing may be briefly deferred, whereas assessment of new respirator users warrants a higher priority.
- Occupational medicine practices should continue policies of airborne and surface exposure control measures, universal patient masking, screening potential patients for likely recent exposure or symptoms, limiting unnecessary visitors to the clinic, and providing appropriate PPE to medical staff members.
- Adequate ventilation of clinical facilities should be assured. Recommendations of ASHRAE and CDC should be followed. For example, an adequate number of air changes per hour, typically at least six, and use of effective in-line filters with a Merv at least 13 should be implemented wherever feasible.
- Reducing transmission in the air in clinics and elsewhere is of primary importance. Since occupational medicine experts have greater understanding of ventilation than most clinicians, they should educate professional colleagues and client companies about the need for adequate ventilation. They should remind others that a 6 foot distance does not guarantee safety from spread, particularly from airborne small aerosols or convective bulk movement of air. Surface cleaning and decontamination is recognized by CDC to have a role, albeit limited, in protection.4 Occupational physicians should remind colleagues to not overemphasize highly visible surface decontamination or cleaning and hand washing, sometimes called "hygiene theater"5, as a substitute for ventilation, PPE, and masks and physical distancing.
- Procedures for reducing the potential transmission with specific clinical procedures such as spirometry were presented in detail in an ACOEM Guidance document in July 2020.6 These recommendations are highly relevant now in face of concern about variants with greater transmissibility. For spirometry, these include use of an effective bacterial/viral filter approved for the specific spirometer, test performance in a well-ventilated area, and PPE for staff. Audiometry procedures should also consider adequacy of ventilation of the area, appropriate surface cleaning or decontamination, and protection of clinic staff.
In summary, ACOEM recommends that physicians regularly look for updated recommendations or requirements from public health agencies and professional organizations, adjust decisions about which surveillance testing to defer based upon local conditions. They should maintain effective exposure control measures such as ventilation, and encourage others to do so.
Most Current ACOEM Statement:
P Harber, M Levine, M. Townsend. Occupational Spirometry and Fit Testing in the COVID-19 Era: Updated Recommendations from the American College of Occupational and Environmental Medicine. https://acoem.org/Guidance-and-Position-Statements/Guidance-and-Position-Statements/Occupational-Spirometry-and-Fit-Testing-in-the-COVID-19-Era-Updated-Recommendations-from-the-Americ
. Accessed 1/20/21