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Nonindustrial COVID-19 Aggravates an Industrial Condition

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As explained previously in LaTourette,[1] the Supreme Court defined two exceptions to the general rule that nonoccupational diseases (such as COVID-19) are not compensable. The second exception concerns cases in which the immediate cause of the injury is an "intervening human agency or instrumentality of employment." This language is confusing, but seems to mean that the employment itself somehow contributed to the cause of the injury.

Cases of Preventive Health Care

An example of this exception was established in Maher v. Workers' Comp. Appeals Bd.[2] The Supreme Court held then that a nurse's pre-existing, nonindustrial tuberculosis was compensable when she was required to undergo treatment for it as a condition of employment, and sustained a significant adverse reaction during the course of treatment. It stated, "California law does not require that employment be the sole cause of an injury, only that it be a concurrent or contributory cause."[3] The court concluded that because treatment of the nonindustrial tuberculosis was required as a condition of her employment, the injury was linked in some causal fashion to her employment, rendering her injury AOE/COE.[4] For further discussion, see "Sullivan on Comp" Section 5.9 Occupational Disease.

The most direct application of Maher would involve a situation in which a worker suffers injuries from the side effects of medication used to treat or prevent COVID-19. For example, if an employer required an employee to receive a COVID-19 vaccine as a condition prior to returning to work, any injuries sustained from the vaccine would be compensable.

Since Maher, Labor Code § 3208.05 was enacted. It defines "injury" as a reaction to or a side effect from health care provided by an employer to a health-care worker that is intended to prevent the development or manifestation of any bloodborne disease, illness, syndrome or condition. This statute essentially extends the rule in Maher for any injury sustained by a health-care worker as a result of preventive health care provided by an employer.

When COVID-19 Aggravates an Industrial Condition

As noted above, "intervening human agency or instrumentality of employment" is confusing language. It could be viewed to mean that any work-related causal factor might be enough to establish industrial injury.

If so, it would be in accord with the general rule that even if an employee's underlying condition was not caused by the employment, a disability or death is compensable if the disease was aggravated or accelerated by his or her work.[5] It has been well-established that the employer "takes the employee as it finds him. A person suffering from a preexisting disease who is disabled by an injury proximately arising out of the employment is entitled to compensation even though a normal man would not have been adversely affected by the event."[6]

For example, in South Coast Framing, Inc. v. Workers' Comp. Appeals Bd. (Clark),[7] an employee died from a combination of drugs prescribed following a fall at work. Some of the drugs were prescribed by his workers' compensation doctor and others by his personal doctor. The qualified medical evaluator (QME) reported that the industrial component was the “minimum level of causation,” colorfully equating it to a couple of crumbs off the crust of 12-inch pie.[8] Nevertheless, the court believed that this was enough to award death benefits.

The Supreme Court explained that for the purposes of causation in workers' compensation, it's sufficient if the work was a contributing cause of the injury. It explained, "Death attributable to both industrial and nonindustrial causes may support a death claim."[9] Accordingly, because the evidence established that the drugs prescribed by the workers' compensation doctor contributed to the employee's death, it was compensable under workers' compensation law. For further discussion, see "Sullivan on Comp" Section 12.2 Compensability –– Employee Death.

Because only a minimal causation is required, an employer might be liable if there is an underlying industrial condition that combines –– to any degree –– with nonindustrial COVID-19 to cause disability or death. The evidence indicates that people with pre-existing conditions (such as diabetes, hypertension, chronic lung disease, heart disease or cancer) have a higher risk for severe illness and death from COVID-19. If an employee with an industrial heart condition, respiratory condition, diabetes or hypertension dies as a result of COVID-19, the employer probably would be liable for death benefits.

The principle of minimum causality goes hand in hand with the established principle that workers' compensation benefits –– with the exception of permanent disability –– are not subject to apportionment. (The employer is not responsible for nonindustrial sources of permanent disability due to the apportionment concept; see "Sullivan on Comp" Section 10.34 Apportionment –– Pre-Existing Disease or Condition.) So, if nonindustrial COVID-19 combines with an industrial condition to create the need for benefits, the employer is fully responsible for the increased need, whether it's for temporary disability, medical care or death benefits. (See "Sullivan on Comp" Section 9.41 No Apportionment of Temporary Disability, Section 7.21 No Apportionment of Medical Care, Section 7.2 Scope of Care –– Cure or Relieve for a full discussion of this obligation, and Section 12.27 No Apportionment of Death Benefit, respectively.)[10] There is no apportionment –– the employer pays full freight.

For example, if an employee had an industrial heart problem and the nonindustrial COVID-19 combined with that problem to cause the employee to miss work, temporary disability benefits would be owed. If the heart problem needed treatment because of the aggravating effects of the COVID-19, the employer would be liable for that treatment. If the worker died from the heart problem because the COVID-19 aggravated it, the employer would be fully liable for death benefits.

Treating COVID-19 as a Necessity for Treating Industrial Injury

An employer is required to treat a nonindustrial condition if it is necessary to cure or relieve an employee from the effects of an industrial injury.[11] That is, if it is necessary to treat a nonindustrial condition in order to treat an industrial condition, the treatment must be provided.

Take, for example, a hypothetical case in which a worker needed heart surgery on an industrial basis, but could not have the surgery because of nonindustrial COVID-19. The virus was not aggravating the heart condition, it was just in the way of the surgery. The employer could be liable for the cost of treating the COVID-19 despite the fact that there was no aggravation, because the treatment was needed to treat the industrial condition.

See Also


  1. LaTourette v. Workers' Comp. Appeals Bd.(1998) 17 Cal. 4th 644, 653.
  2. (1983) 33 Cal. 3d 729.
  3. Maher v. Workers' Comp. Appeals Bd. (1983) 33 Cal. 3d 729, 736.
  4. Maher v. Workers' Comp. Appeals Bd. (1983) 33 Cal. 3d 729, 737-738.
  5. Smith v. Workers' Comp. Appeals Bd. (1969) 71 Cal. 2d 588, 592.
  6. Lamb v. Workmen's Comp. Appeals Bd. (1974) 11 Cal. 3d 274, 282.
  7. (2015) 61 Cal. 4th 291.
  8. South Coast Framing, Inc. v. Workers' Comp. Appeals Bd. (Clark) (2015) 61 Cal. 4th 291, 296.
  9. South Coast Framing, Inc. v. Workers' Comp. Appeals Bd. (Clark) (2015) 61 Cal. 4th 291, 300.
  10. See alsoGranado v. Workmen's Comp. App. Bd. (1968) 69 Cal.2d 399, 404.
  11. Braewood Convalescent Hospital v. Workers' Comp. Appeals Bd. (Bolton) (1983) 34 Cal. 3d 159.

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