Health Checks | Gorilla Doctors

Part 3: Lab Work and Follow-Up

Category: Field Procedures, Monitoring Visits | Date: Jan 06 2009 | By: Dr. Jan Ramer for gorilladoctors

After a brief break for lunch, Magda, Jean Felix, and I met back in the lab. We spent the next five hours doing all we could to process and run the gorillas’ samples, but we ran out of energy before we could finish. I think we also felt a bit deflated when we didn’t find mites in the hair or skin samples. But we did discover one new, important fact: Icyizere was anemic, too, although not as severely as Mushya. This meant the mother’s health could also be a factor, something we hadn’t suspected.

Close up of the skin on the top of Mushya’s head

The good news, of course, was that we didn’t find scabies. Additionally, Mushya showed no evidence of organ dysfunction. His kidneys and liver were functioning normally, which meant they weren’t the cause of his stunted growth or anemia. As we thought more about what might explain his problem, we reviewed our findings on Icyizere so far. Her blood work was also normal, except for the mild anemia I mentioned, but her fecal sample from the day before had been loaded with parasites—and, at least one type does feed on the host’s blood. A new explanation emerged: maybe Mushya also had a high parasite load like his mother. A phenomenon called endoparasite migration can cause itchy skin.

It was near 10 o’clock at night and time to quit for the day. We’d collected a fecal sample on Mushya and would run it first thing in the morning. I walked the 50 meters to my little house wondering why we hadn’t considered internal parasites as a possible cause of Mushya’s condition. I knew the answer. First, we’d been focused on external parasites, the mites, because they can be highly infectious. We also didn’t expect to find a problem with Icyizere. Additionally, most animals that live in the wild, including mountain gorillas, carry parasites; finding them is nothing new. They haven’t caused serious illness very often, however.

Thankfully, ivermectin rapidly kills endo- (internal) as well as ecto- (external) parasites. If it turned out that the only problem was parasites, both Icyizere and Mushya had a very good chance of feeling better—soon.

Magda and Jean Felix collecting samples from Icyizere and Mushya during the intervention

The next day, I woke up feeling a bit anxious. Even though yesterday’s procedure had gone well and we had no reason to expect problems, we wouldn’t know for certain until we saw Icyizere with Mushya back in their group. I was also wondering what we’d find from rest of our lab work. My plan was to go back up to the forest to check on mother and infant while Jean Paul, our lab manager, headed here to Ruhengeri. He didn’t mind coming in on a Sunday, but it would take some time, since he lives two hours and a border crossing away in another country, in Goma, DRC.

Processing samples after an intervention is critically important and painstakingly slow. There are protocols to follow for labeling and processing every sample. All mountain gorilla biological samples become part of a “biobank” which is made available to all researchers for future study. So we save everything, from bits of hair to drops of blood. Eventually, we send the samples to the USA for further or repeat expert analysis, but when we have an active case, we’re the experts. I’d asked Jean Paul to take another look at the skin scrapings for mites and run the fecal on Mushya. I’d bring back a fresh sample from Icyizere.

On our way back up to Isabukuru Group, Emmanuel was the lead tracker. Luckily for my nerves, he has very long legs and I have to race to keep up—a good distraction whenever I’m worried. Instead of thinking about the gorillas, I focused on keeping the sweat off my eyeglasses so I could see where to place my feet. Before long, we’d reached the site of yesterday’s intervention a full hour earlier than we had the day before. Well, I said Emmanuel was fast!

Isabukuru had moved on. The question was how far?

In my experience, there’s a delayed reaction within the group the day after a darting procedure. The animals seem calm right afterward, but then, either later that day, or early the next morning, the group moves. I wonder if there’s some kind of communication that something bad or scary happened. Emmanuel didn’t think this would be the case with Isabukuru. He’s a young, calm silverback, at least judging by his behavior in the past. We’d also been careful not to give him any indication that we were up to something the day before. As long as the gorillas don’t see the dart gun or the person pointing it, the rest of the event causes minimal, if any, disruption.

Emmanuel found Isabukuru’s trail and quickened his pace. I crossed my fingers that he was right and that the group wasn’t far away. Otherwise, I’d have to ask him to slow down. We were in thick vegetation with nettles, thorns, and downed branches. For every one of Emmanuel’s steps over a fallen tree or deep hole, I had to take two—or jump. Fortunately, we reached the group 30 minutes later. Emmanuel had been right. The gorillas didn’t even react to our presence.

Mushya with Icyizere the day after the intervention

We found Icyizere and Mushya with no trouble. The infant turned to stare at me as he’d done each day before. He was a funny-looking baby. The remaining hair on the top of his head stood straight up and the bald spot on the left side shone white in the sunlight. He clung to his mother’s right hip as she ate thistle. As Icyizere reached out for another handful of food, I noticed several new behaviors. The mother was eating double fisted, instead of holding onto her baby with one hand. Mushya appeared stronger, moving around from her belly to her back and returning to her hip with greater ease than we’d seen the day before. More important, he wasn’t itchy. I saw him rub his forehead just once in the course of the next hour and a half.

Mushya close up, the day after the intervention

Emmanuel smiled and said “Forte,” meaning “strong” in French. I said “Oui!” and gave him a thumbs up. Clearly, our intervention had done no harm. On the contrary, it appeared to have done some good already. We watched Icyizere join the other gorillas in a nearby Hygenia tree. She easily scaled the wide trunk, using both feet and hands, and climbed out along one of the limbs, leaning over at precarious angles to pick handfuls of leaves from the underside of the branches. I may be exaggerating the change, but she seemed like a different gorilla, and so did Mushya. He held on without any help from his mother, riding out the feeding session with no problem.

Mushya holds on to Icyizere even as she feeds from a tall Hygenia tree

Back in the lab, Jean Paul confirmed that the baby did indeed have a moderately high parasite load, including adult forms of two different parasites. Additionally, the fresh sample from Icyizere showed a moderate load of two, instead of three, parasites. The ivermectin may have already started to work. But one fecal sample on any given day can be negative even if the parasites are still there, depending upon the stage of the worm’s lifecycle. We may or may not find eggs, larvae, or adult worms. We’re not expecting one dose of medicine to clear either mother, or infant, of parasites. What we do hope is that the ivermectin will reduce their worm loads and help them regain their body condition—and their red blood cells. If one treatment isn’t enough, we may decide to repeat the intervention.

Meanwhile, we need to understand what is happening with parasites in the rest of the group. Tomorrow we’ll start a weekly screening of all the members of Isabukuru’s family. There may be several pieces missing from this puzzle. It’s still not clear why parasites that normally don’t cause serious illness took hold in this mother/infant pair, or if this is their only problem. Time—and lots more fecal samples—will tell.

Mushya and Icyizere in a tall Hygenia tree the day after the intervention