In October 2015, at the height of West Africa’s Ebola epidemic, a woman in rural Guinea arrived at an Ebola treatment center bleeding from her gums. Like many women, she had been the caretaker for someone who had recently died of the disease. Anyone else likely would have received the new, experimental Ebola vaccine. But she wasn’t anyone else — she was pregnant.

If it hadn’t been for what happened next, we likely never would have heard the Guinean woman’s story. (Her name has been withheld for privacy.)

Rushed to a treatment center in Conakry, the capital city of Guinea, her and the fetus’s likelihood of survival was almost zero. She was treated with an experimental drug called Favipiravir and four days later gave birth to a baby girl who was given ZMapp, an experimental Ebola drug.

The baby girl, named Nubia, would become the first infant to survive Ebola. Her mother died just hours later.

Nubia’s mother was the first of hundreds, likely thousands, of women who for years would be denied the life-saving Ebola vaccine out of fear that it could negatively impact fetuses.

That all changed this week when, in the midst of the Ebola outbreak currently roiling the Democratic Republic of Congo, the country’s ministry of health and the World Health Organization made a landmark policy reversal allowing pregnant women to receive the Ebola vaccine — which, while still experimental, is widely believed to be safe and effective.

The change of heart isn’t just a dose of hope in what is now the second-largest Ebola outbreak in history, with more than 500 people dead — it’s a reversal that could have implications for how pregnant women fare in infectious disease outbreaks for years to come.

Pregnant women and pandemics around the world

While the prognosis for Ebola — a devastating and highly contagious virus that wreaks havoc on the human body, causing internal bleeding and damage to almost every organ — is bad for anyone, it is particularly deadly for pregnant women.

Some data show that between 80 and 90 percent of all pregnant women with Ebola die, while death rates for the general population hover closer to 50 percent. Babies of mothers infected almost never survive. Among infectious diseases, Ebola isn’t unique in this sense.

“There is nothing about pregnancy that makes women or their babies immune from infectious disease threats, and more often than not, pregnant women and their babies face even greater consequences from these infections,” says Carleigh Krubiner, a policy fellow at the Center for Global Development and faculty at Johns Hopkins Berman Institute of Bioethics.

As the world becomes more interconnected, the threat of large-scale disease outbreaks like the West African Ebola outbreak, which claimed 11,325 lives across multiple countries, is becoming increasingly acute. As the Centers for Disease Control puts it:

“While we can’t predict exactly when or where the next epidemic or pandemic will begin, we know one is coming.”

There’s growing evidence that pregnant women will face some of the most dire risks of future pandemics. With hepatitis E, as many as 30 percent of pregnant women die from the infection, compared with an overall mortality rate that’s between 0.5 to 2 percent. With influenza, pregnant women get seriously ill at much higher rates. With Lassa fever, endemic to West Africa, maternal and/or fetal loss during pregnancies in the third trimester occurs in more than 80 percent of cases.

Despite this, and despite the fact that there are more than 200 million pregnancies per year worldwide, pregnant women are almost always excluded from vaccine research and deployment.

Why aren’t pregnant women included in vaccine research?

“It’s a risk benefit decision: if you have a disease that is highly lethal, essentially 100 percent in a fetus and at least 60 to 70 percent lethal in a pregnant woman, does the risk-benefit rationale of giving an experimental vaccine that appears to be highly effective outweigh the risk of causing some sort of adverse effect of the vaccine in the mother and the infant?” asks David Schwartz, the series editor of Global Maternal and Child Health: Medical, Anthropological, and Public Health Perspectives, in reference to the Ebola vaccine.

“For many of us in the public health community, we felt that it did outweigh the risk, but for some other people, it did not.”

It’s an oversight that may seem surprising, but the exclusion of women from clinical trials isn’t anything new. In fact, writes Schwartz, pregnant women have never been prioritized in the development or clinical testing of pharmaceuticals or vaccines.

In the United States, according to a 2013 analysis, pregnant women are excluded from 95 percent of industry-sponsored clinical trials; just one percent target them. As a result, the vast majority of drugs prescribed to pregnant women are “off-label,” which means they haven’t gone through the clinical trials typically required by the Food and Drug Administration before approving their use for a specific population. Dr. Cheryl Broussard, a health scientist at CDC, has said that "Less than ten percent of approved medications have enough data to show what, if any, concerns there are for fetal effects."

It isn’t just pregnant women: It wasn’t until 1993 that American law required clinical trials to include women at all.

Research on vaccines hasn’t been any different — until now.

What vaccinating pregnant women will mean for the future

Deploying the vaccine to pregnant women in the current outbreak will be as promising as it is challenging.

This is the country’s tenth Ebola outbreak, but it is the first in an active war zone. The virus erupted last August in the thick of one of Eastern Congo’s most entrenched conflicts, a region that Dr. Jean-Christophe Shako, an Ebola response coordinator, described in a piece for IRIN as “a densely populated, heavily travelled urban region where about 100 armed groups operate,” which doesn’t just make responding difficult, it makes the chance of geographic spread incredibly high.

Amidst the violence, and populations constantly fleeing that violence, health workers will have to develop protocols to ensure that pregnant women are aware of the potential risks of the vaccine while also tracking women who receive it over years to determine whether they ever develop negative effects.

“This will also be a critical opportunity to collect data to better understand the safety profile of this vaccine in pregnancy,” says Krubiner.

“The hope is that we’ll never again be in a situation like this, in which we only have a non-ideal option to offer pregnant women and an insufficient evidence base.”

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