Both biology and behaviour play a part in why the coronavirus hits men harder than women. Photo: peakpx.com

As the coronavirus sweeps the globe, it seems indiscriminate in its attack, taking down anyone exposed to it. But a pattern is emerging: men seem to be hit harder than women.

Is it biology, behaviour, or both?

Women tend to have more robust immune responses, but as a consequence, are more prone to autoimmune diseases such as rheumatoid arthritis and lupus. But this may also mean women are better protected against invading viruses, since their initial immune reaction is stronger than their male counterparts. 

“Sex hormones like testosterone and estrogen are important in modulating the immune response,” says Veena Taneja of the Mayo Clinic, who studies differences in male and female immune systems. 

One hypothesis is that women’s stronger immune systems confer an advantage to their offspring. Antibodies from mothers’ breast milk help ward off disease while infants’ immune systems are still developing.

Another explanation may be genetic. Women have two copies of the X chromosome, which contains many immune-response genes. Men have only one.  Taneja says that while a female’s extra X chromosome is generally silenced, around 10 percent of these immune-boosting genes can be activated. It’s possible for women to get a "double-dose" of protection — although the research is still at an early stage, and it's still too soon to know exactly how all this might play out in the context of COVID-19.

Men may also be disadvantaged by higher concentrations than women of a biomarker associated with increased pulmonary, gut, renal, central nervous system, and cardiovascular manifestations. A recent study published in the European Heart Journal suggests this biomarker, angiotensin-converting enzyme 2 (ACE2), indicates susceptibility for the coronavirus to infect healthy cells. This may help to explain why men are more vulnerable to SARS-CoV-2 (the COVID-19 virus) than women.

Over the last two decades, men were also disproportionately affected by SARS and MERS outbreaks, both caused by coronaviruses. A study published in the Annals of Internal Medicine, found that more women than men were infected by SARS in Hong Kong in 2003, but the death rate among men was 50 per cent higher.

It is clear that being male may be a risk factor for COVID-19, just like being older or having medical conditions like asthma or heart disease.

Gender differences in our vulnerability to the coronavirus are also shaped by social norms and practices. Photo: pixabay.com

Men’s behaviour may also be working against them during this epidemic. Men often don't seek health care until they feel more symptoms and so are less likely to seek out testing for the coronavirus when they feel sick. This might be because many men are taught to be self-sufficient, seeing self-care as an admission of weakness. This may result in ignoring tell-tale symptoms of the coronavirus. Other behaviours that affect general health such as smoking, may also play a role in the disease’s disproportionate impact on men. 

Pollution could also be playing a role. In most cultures, men are more likely than females to work outside, exposing them to pollution and its associated risks for lung disorders. 

Since the start of the COVID-19 outbreak, public health officials have emphasized the importance of hand washing and hand sanitizing to prevent infection. But a study done by the Hong Kong Polytechnic University found that men — even those who are healthcare workers — are less likely to wash their hands or to use soap than women. These men also tend to be less compliant with pandemic-related restrictions such as physical distancing.

When it comes to this latest coronavirus, there is a tendency to group cases by criteria such as age and social standing and make broad assumptions that both men and women are equally affected. They are not. It’s a lesson for both the public and the scientists who are gathering and analyzing data about the new virus.

By: Sara Chung

Sara was born and raised in Singapore, and has lived in Canada for more than a decade. She completed her B.Sc. at the University of Toronto, majoring in Neuroscience and Psychology, and currently works in the tech sector. With coffee and tea flowing through her veins, she takes life on with high dopamine and serotonin levels!

For more details, please check out her LinkedIn: https://www.linkedin.com/in/sara-chung/