Boko Haram is leaving a major healthcare crisis in its wake

Nigeria's military has been busy chasing Boko Haram militants out of large swaths of the country's northeast over the last year, pushing fighters out from their camps and strongholds. But as the troops clear out militants, we're starting to see the true scope of what they left behind — a health crisis, and almost a million more people facing dire conditions than previously thought.

For the first time, humanitarian organizations are entering areas across Nigeria's Borno State that were held by Boko Haram for years and then caught in the crossfire between the militants and the army. What they are finding is mass malnutrition, worrying epidemics, and a logistical nightmare.

Recent visits, made possible by military escorts because the security situation remains unstable, found more than half of all medical facilities non-functional. Even healthcare centers still up and running are understaffed and short on supplies. There are least 800,000 people in the newly reached areas with urgent health problems, adding to the 7 million in the northeast region already in need of emergency assistance, according to the World Health Organization.

Fifteen percent of the people in areas newly liberated from Boko Haram also display severe acute malnutrition, the health agency said. Just last week experts confirmed new cases of polio in the area, the first new outbreak in Africa in two years. Measles cases have also been identified. The WHO is already conducting a vaccination campaign against both.

"There's been a lot less on the TV screens of what's going on in Nigeria, but believe me it's very, very dire," Dr. Richard Brennan, the emergency operations director for the UN health agency, said on Tuesday.

The latest revelations have pushed the World Health Organization to announce that it's scaling up its emergency response, in one of the most challenging places in the world to deliver humanitarian aid. An emergency response team is on its way to Nigeria to help as the health agency works with other organizations to reduce death rates and improve medical care.

With the rainy season coming soon, the focus will also be on setting up shelters, delivering supplies, and providing food. Brennan said severe flooding is expected this season, which will make the logistics of the operation even more challenging. In June and July, teams from Doctors Without Borders, or MSF, were the first aid workers to enter several towns outside the capital Maiduguri that had previously been cut off, and highlight the humanitarian needs in these isolated areas.

Follow Kayla Ruble on Twitter: @RubleKB