Natural disasters are thought to be indiscriminate killers – but is that strictly true?

It turns out disasters affect women much more than men. A 2007 study by researchers at the London School of Economics and the University of Essex found that between 1981 and 2002, natural disasters in 141 countries killed significantly more women than men, and that the worse the disaster, the bigger the gender disparity.

The latest figures from Nepal show that among the 1.3 million affected by the earthquake, about 53% are female – a small but not yet statistically significant bias.

That might soon change. According to the Women Resilience Index, a metric developed to assess a country’s capacity to reduce risk in disaster and recovery for women, Nepal scores a paltry 45.2 out of 100. Japan scores 80.6, by comparison, and Pakistan 27.8.

And lessons from previous disasters show that the bias affecting women can worsen in post-disaster relief.

Is biology destiny?

There are many factors that contribute to this bias – both social and biological.

For instance, the excess female deaths during both the 2001 Gujarat and the 1993 Maharashtra earthquakes, which killed 20,000 and 10,000 people respectively, were blamed on the fact that more women were indoors while men were in open areas.

In 2004, when the third-largest earthquake in recorded history triggered a tsunami in the Indian Ocean, up to four women died for every man in hard-hit Aceh, Indonesia. One factor: women in Indonesia do not usually learn how to swim or climb trees.

During and after the 1998 floods in Bangladesh, many women suffered from urinary tract infections, due to the lack of sanitation and the taboo attached to menstruation.

“Common cultural practices dictate that women’s needs for privacy tend to be higher, so relieving themselves in public is harder than it is for men. Menstruating women face additional difficulties when access to water is lost or limited,” a spokesperson from the international aid agency Oxfam told Quartz.

After the calamity

The discrimination doesn’t stop after the immediate search and rescue is over. Sushma Iyengar, a social educator who works in Gujarat, told Quartz that during the 2001 disaster, “there was a much higher percentage of orthopaedic injury – and a lot of people got spinally impaired. And among those who became paraplegic, a huge number were young women, because they happened to be inside their houses.”

The paraplegic young women then became more vulnerable to the risks of their husbands leaving them if they were alive. “Not immediately after the calamity, but as the reality unfolded, and families come to know that the woman is not going to bear children, and that she is spinally impaired, and dependent, and she will not be earning, so she was abandoned,” Iyengar said. “It’s too early to figure out the extent of injuries, but what happened in Kutch [site of the Gujarat earthquake] might unfold in Nepal, too.”

Women are typically more vulnerable than men, especially in patriarchal societies, due to issues of personal safety and violence and access to scarce resources. Therefore, when a calamity strikes, the situation is accentuated.

“In calamities, you’ll see the best of humankind for the first few days. And then slowly, as the struggle looms large that you’re going to be without shelter and livelihood, that’s when a lot of conflicts occur,” Iyengar said. “At such times, women are vulnerable to different forms of trafficking and exploitation.”

report by the UK department of international development refers to this as “double disaster,” where indirect or secondary impacts make life worse for women. But some efforts are being made to address the disparity.

Flipping the situation

In Nepal, the plight of thousands of pregnant women is being given particular attention. The UN Population Fund, for example, is distributing hygiene and reproductive health kits.

Such efforts have in the past been shown to have a two-fold benefit. Not only are the lives of women improved, but many of them then get involved in relief activities. Local women, for instance, are the most effective at mobilising their communities.

For instance, an Indian non-governmental organisation, Swayam Shikshan Prayog (Hindi for “learning from one’s own experiences”), which had been focused on helping women in disasters for 15 years, helped spearhead a programme to help rebuild homes after earthquakes in Maharashtra and Gujarat.

So those working on relief efforts in Nepal would do well to pay a little more attention to the needs of women. The rewards would be well worth it.

This article was originally published on qz.com.