Women who are pregnant and lactating, as well as children under the age of 1, will be offered access to an experimental Ebola vaccine in the Democratic Republic of the Congo, officials said Wednesday, marking the reversal of a controversial policy that had drawn fire from public health experts.

The decision was made by a committee advising the Congolese Ministry of Health, but received the support of the World Health Organization. It followed an outcry over the exclusion of pregnant women from the vaccination program, with some experts calling the initial policy “indefensible.”

Proponents of the earlier policy argued that the vaccine, which goes by the provisional name V920, might harm the fetus or trigger a miscarriage. They noted that there were no data to show the vaccine was safe to use in this very vulnerable population.

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But critics countered that unless the vaccine is used in pregnant women there would never be data to determine whether it was safe. And they noted that while there may be some risk involved in vaccinating pregnant and lactating women, the risk to them from Ebola is greater. Some studies have suggested that 90 percent of pregnant women who are infected die, and fetal loss is almost a given.

The decision to exclude lactating women stemmed from concerns the vaccine viruses might be transmitted via breast milk. Children under the age of 1 were excluded from vaccination because the vaccine’s safety and effectiveness in this group hasn’t been tested. (An earlier decision to lower the threshold for those eligible for vaccination from 6 years old to 12 months old was made without the benefit of a clinical trial.)

With supplies of the vaccine limited, health officials in the DRC have been offering it to people who have been in contact with an Ebola patient — people who have a real risk of contracting the disease. Contacts of the contacts are also eligible. The goal is to protect everyone in the virus’ path, eventually blocking its opportunity to continue to spread.

As of Tuesday nearly 82,000 people in North Kivu and Ituri — the provinces where the outbreak is occurring — have been vaccinated. The vaccine, which has yet to be licensed, is being developed by Merck.

Carleigh Krubiner, a policy fellow at the Center for Global Development, welcomed the news.

“The DRC’s decision to extend Ebola vaccine coverage to pregnant women is a huge step forward, not only for pregnant women in areas affected by outbreaks but for all pregnant women who may face the threat of Ebola in the future,” Krubiner said in a statement.

To date there have been 848 confirmed and probable cases in this outbreak, which is now in its seventh month. Of those, 529 people have died. The WHO estimates that 57 percent of those cases are women; 35 percent of the total cases have been women of childbearing age.

Children, too, have made up a startling share of the cases in this outbreak. Just under a third of cases have been children under the age of 18, and half of those have been in kids under the age of 5, the U.N. International Children’s Emergency Fund (UNICEF) reported in its most recent update.

Krubiner said the policy reversal will not only offer pregnant women the protection of the vaccine, but also provide a critical chance to see how the vaccine works in these women. That knowledge will be of benefit in future outbreaks, she said.

The experts who advise the WHO on vaccine policy — the strategic advisory group of experts on immunization, known as the SAGE  — stressed that if the vaccine is to be used in these new groups efforts must be made to collect data that can inform future policy on the safety and effectiveness of the vaccine for babies and pregnant and lactating women.

The decision was also applauded by Doctors Without Borders, which had opposed the exclusion of pregnant women.

Dr. Séverine Caluwaerts, a Belgian gynecologist who volunteers with MSF —the acronym is based on the organization’s name in French — said in reality some pregnant women have already received the vaccine, because they were vaccinated before they knew they were pregnant. MSF has heard reports of at least 20 such cases in this outbreak, Caluwaerts said.

She argued there’s a bigger picture that needs to be considered. When Ebola kills women of childbearing ages, it also endangers the lives of young children they leave behind.

“The most important factor for child survival in Africa is an alive mother,” said Caluwaerts. “There are data [that suggest] if your mother dies at birth your chance of becoming 5 years old are, like 10 percent, because your mum needs to be there to take care of you.”

Already this outbreak has created a large number of orphans. The most recent UNICEF report, dated Feb. 3, said that 908 children have either been orphaned or separated from parents as a result of the outbreak so far.

Reluctance to offer the vaccine to pregnant and lactating women is based on the fact it is a live-virus vaccine. The virus it contains is not Ebola; it is a livestock virus called vesicular stomatitis virus that can infect, but does not sicken people. A key protein from the Ebola virus has been fused to the VSV virus, which then prompts the immune system to develop a protective response to Ebola.

Traditionally there has been concern about using live-virus vaccines in pregnant women. Krubiner and others have argued that women ought to be informed of the risks and offered the choice.

Dr. Jon Abramson, a pediatric infectious diseases expert at Wake Forest School of Medicine, notes there is a precedent here. Several years ago the SAGE — which he chaired from 2013 to 2016 — agreed that during dangerous yellow fever outbreaks pregnant women should be offered the chance to be vaccinated. The yellow fever vaccine is also a live-virus vaccine and it is known to cause serious side effects in a small portion of people who receive it.

Abramson said the circumstances of this outbreak warrant consideration of dropping the vaccine exclusions.

“I think it is reasonable, given the particular epidemiology and the number of children dying, to think about using it,” he told STAT. “Because at least we know that the vaccine works in other age groups.”

“But if we’re going to do that, we need to also get the data to tell us how effective it is in pregnant women and children,” he insisted.

It was not immediately clear whether all children — even newborns — could be vaccinated. Nor is it clear how the WHO feels about this part of the decision. The statement from the SAGE committee said it “welcomes and supports’’ the DRC’s decision to offer the Ebola vaccine to pregnant women and “acknowledges” the decision to offer it to children under 1.

The WHO did not immediately respond to a request for an interview.

A spokeswoman for the Congolese Ministry of Health, Jessica Illunga, said it would not make any statement on the policy change until a final pending authorization had been approved later this week.

In another Ebola vaccine development, the report from the SAGE committee revealed that the group has recommended the testing of other experimental Ebola vaccines during this outbreak.

Three in particular were considered: one made by Johnson and Johnson and a Russian and a Chinese vaccine. The latter two have been licensed in those countries, but none of the three has been proven to be protective in a Phase 3 clinical trial.

The committee recommended that these vaccines could be used in clinical trials that enroll health care and front line workers in areas around the outbreak zone — areas where Ebola is not transmitting but might at some point.

Pregnant and lactating women could also be enrolled in these trials, the committee said, because the formulations of the other vaccines are different and do not raise the same safety concerns.

Talks about using other vaccines in DRC or potentially neighboring countries during this outbreak have been ongoing for months. It is not clear how quickly the other vaccines might actually be deployed.

 

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