The UK government recently announced a dramatic U-turn on the COVID vaccine mandate for healthcare workers, originally scheduled to take effect on April 1 2022. Health or social care staff will no longer need to provide proof of vaccination to stay employed. The reason, as health secretary Sajid Javid made clear, is that “it is no longer proportionate”.

There are several reasons why it was the right decision at this point to scrap the mandate. Most notably, omicron causes less severe disease than other coronavirus variants; many healthcare workers have already had the virus (potentially giving them immunity equivalent to the vaccine); vaccines are not as effective at preventing re-infection and transmission of omicron; and less restrictive alternatives are available (such as personal protective equipment and lateral flow testing of staff).

But the question remains: what does this imply for vaccine mandates more generally? In a Twitter thread, former UK health secretary Jeremy Hunt has expressed concerns that the U-turn will make it harder to implement vaccine mandates in the future. This might be true politically, but ethically, it doesn’t follow. Indeed, this provides an opportunity to reflect on when such mandates are ethically justifiable – or even required.

The ethical principle that justifies some forms of mandatory vaccination of health professionals remains: healthcare professionals have a fundamental duty to minimise the risk of harm to patients. This includes taking reasonable steps to protect patients from infection. The General Medical Council and the Royal College of Nursing have previously made it clear that unless they have a medical reason, doctors and nurses have a duty to have vaccines against serious communicable diseases. It is, arguably, required by the Hippocratic oath.

When would a mandate be ethical?

At least four factors are relevant when considering whether it’s justifiable to make vaccines mandatory for healthcare workers.

1. Will the mandate increase vaccine uptake?
2. Will the mandate reduce infection in hospitals and clinics?
3. Are the health benefits for patients proportionate to the risks for healthcare workers?
4. Are less restrictive policies available that can achieve similar outcomes?

With omicron as the dominant variant, a mandate would not satisfy those conditions. But mandates for other vaccines might well do.

Take the flu, for instance. Most people aren’t aware of the risk of catching the flu in a hospital. However, COVID has made the problem of hospital-acquired infections more evident. During the first wave of the pandemic in 2020, up to a quarter of COVID hospitalisations may have been caught in hospital. Up to a third of COVID deaths in Scotland in 2020 were considered “definitive hospital onset”.

A similar problem occurs with flu. For example, during the 2018-19 flu season, 15% of patients hospitalised with the flu at London University College hospitals were estimated to have caught it in hospital. Hospital-acquired flu infection is associated with high mortality - with about 27% of cases being fatal. And the uptake of the flu vaccine among healthcare workers is patchy. In the last winter season (2020-21), around a quarter of frontline healthcare workers in England hadn’t had the flu jab. Some NHS Trusts had only around 50% uptake.

For the flu vaccine, mandatory vaccination for healthcare workers is much more effective than less restrictive alternatives (condition four), at increasing vaccine uptake (condition one), and at reducing hospital transmission (condition two).

It has also been shown to reduce overall deaths from pneumonia and flu and it is effective at reducing staff absenteeism due to illness. Importantly, the flu vaccines have been extensively researched over decades and there is a high degree of confidence about their safety. This makes even a small marginal benefit resulting from a vaccine mandate worth the mandate for healthcare workers (condition three).

There is a strong ethical case that those who work in the health and social care sector should be required to have the seasonal flu vaccine as a condition of employment. If a new, more serious – but vaccine-preventable – variant of SARS-CoV-2 were to emerge, that might also apply.

One reason provided for the U-turn on COVID vaccines is the fear of critical staff shortages. But that would not necessarily apply if staffing problems in the NHS are addressed. In the US, large hospitals that have mandated flu vaccination have not had significant staff losses as a result.

Ethical principles are not relative, but what course of action they prescribe depends on the circumstances and the facts. While the U-turn on the COVID vaccine mandate was ethically justified, we shouldn’t rule out mandates altogether.

The Conversation