Radical gender ideology—the belief that whether one is male or female is rooted in subjective feeling, not objective fact—has gained devoted adherents in the most influential spheres of our culture. The argument that one’s chosen gender should override biological sex has taken hold even when it comes to medical care.

The coronavirus pandemic, however, has again highlighted the importance of basing medicine on scientific facts. Though much is still unknown about the virus and its effects, there is strong evidence that it affects men and women differently.

Early statistics from Italy, where the outbreak has been severe, indicated that many more men than women have died from the disease, with men constituting more than 70% of COVID-19 deaths. As scientists and medical professionals race to find effective treatments for the virus and provide the best possible care, they need clear data, including accurate records of basic information—such as a patient’s sex.

The United Kingdom’s National Health Service, for example, has long since adopted transgender ideology in an attempt to placate activists. But now this choice may be putting its coronavirus patients at greater risk.

An online questionnaire intended to help screen patients who think they may have contracted the virus includes a standard request for patients to specify whether they are male or female. Next to this question, however, the website provides a link titled “Why aren’t there more options?” beyond those two categories. Users who follow this link are informed that “Some clinical assessments can be different depending on your sex. Not everyone sees themselves as female or male” and that they should call the NHS hotline “if neither option is right for you.”

Unfortunately, this isn’t an isolated incident of ideological activism gaining a foothold within the medical community. On March 13, just as authorities in the U.K. and the United States were announcing drastic new measures to slow the spread of the virus, the NHS website published a blog post titled “Ensuring pregnant trans men get equal quality care,” demonstrating just how deeply embedded transgender ideology has become in Britain’s state-run healthcare system.

Science has consistently recognized sex as an objective physical trait determined by an organism’s overall organization with respect to reproduction. Humans, like other mammals, are a sexually dimorphic species, with recognizable characteristics distinguishing males and females. Every cell in the body carries chromosomes that indicate a person’s sex and direct physical development.

This reality has well-recognized implications for medical care. Men and women have notably different rates of illness, heart disease, and diabetes, and they differ in their responses to medication, which is critical knowledge when treating a patient.

Subjective gender identity or social presentation is no substitute for biological reality when it comes to medicine. As the NHS’s questionnaire indicates, sex distinctions do matter when treating COVID-19.

The preference for politics and ideology over science has led to confused messaging from activists. A coalition of more than 100 prominent activist groups recently released a joint letter claiming that gay and transgender people are particularly vulnerable to coronavirus due to higher rates of smoking, a higher population of immunosuppressed individuals due to the treatment of HIV and cancer, and invidious discrimination in the medical system.

The city government of San Francisco’s official website provides similar information and advises residents who identify as transgender to be aware of their heightened risk. If people who identify as LGBT are in particular danger from the virus, then we must be unified in working to ensure that they get the best medical care possible. However, continuing denial of the relevance of biological sex to treatment creates a needless complication in ensuring everyone receives lifesaving medical care.

Substituting self-determined gender identity for the scientific fact of biological sex dangerously gambles with human life. At some point, activists will have to choose one or the other: concede to biological reality or maintain their ideology at all costs—which would mean endangering the lives and health of the very population for which they advocate.

As the COVID-19 pandemic continues to unfold, the vital importance of keeping politicized ideology out of medicine is becoming clearer by the day.