USF College of Public Health doctoral candidate Caitlin Wolfe spent her summer responding to an Ebola outbreak in the Democratic Republic of Congo (DRC) and conducting research for her dissertation on schistosomiasis in Senegal.
On May 8, the Équateur province in the DRC reported confirmed laboratory cases of Ebola in the region. It only takes one laboratory confirmed case to declare an outbreak.
About a week later, Wolfe was contacted by her former colleagues in the World Health Organization (WHO). They sought her expertise from her Ebola response days in Liberia during the West African outbreak and wanted to see if she had any availability to support their current efforts.
“All responding agencies and organizations were pretty concerned that there was a chance this outbreak might spread further, especially once a confirmed case was detected in the large port city of Mbandaka,” she said. “With a population of over one million and its convenient location along the Congo River, if the outbreak continued to spread through Mbandaka it could have easily reached the capital city of Kinshasa, where roughly 12 million people reside.
Wolfe arrived in June and supported the WHO’s African Regional Office (AFRO) in Brazzaville, Republic of Congo, across the river from the DRC. There she assisted AFRO’s Health Information and Management (HIM) division of the Health Emergencies Programme through ongoing Ebola and other disease surveillance efforts while regular staff members were deployed out in the field.
“On July 24, after 54 cases, the outbreak was thankfully declared over. Unfortunately, about one week later, another Ebola outbreak was declared on the opposite side of the country in the North Kivu province, this time bordering Uganda in a region that has been fraught with instability and conflict,” she said. “There are multiple armed groups operating there. As of October 21, that outbreak is up to 237 cases and 202 of them have been laboratory confirmed. All responding agencies have been told they can only send in very small teams because the poor security situation, so that outbreak has been more challenging.”
Since this interview was conducted, the number of confirmed and probable cases has risen to 177, 142 of which have been laboratory confirmed. Wolfe continues to support the efforts of the WHO AFRO HIM team remotely now that she is back in Tampa, Fla.
After spending four and a half weeks in Brazzaville, Wolfe traveled to Senegal to continue her research on schistosomiasis.
Schistosomiasis is a parasitic disease that can affect the blood vessels leading to the intestines or bladder, depending on the species of the parasite an individual is infected with. The parasite requires freshwater snails to complete its life-cycle and is found commonly in places with poor sanitation. People living in endemic areas often get infected when they go to their local water supply to collect water, wash their clothes or bathe.
When people come into contact with the contaminated water, the parasites that were released from the fresh water snails can enter the skin and travel through the body. When a male and female worm finds their way to their preferred location in the body, they attach themselves to the blood vessels and start to lay eggs. Most eggs are passed through feces or urine, depending on which parasite species one is infected with, but the eggs can also start to accumulate elsewhere in the body as they travel through the bloodstream. This accumulation can cause an inflammatory response from the immune system. Common symptoms include nausea, vomiting, diarrhea, blood in the urine or stool, and weight loss. It has also been linked to bladder cancer in some regions of the world due to the prolonged inflammation from the infection.
Wolfe said that about 200 million people are infected with schistosomiasis around the world and that another 800 million are at risk of becoming infected.
In northern Senegal, where Wolfe is conducting her research, schistosomiasis infections are common due to the adverse effects from the Diama dam that was built in the 1980s to increase farming.
“When the Diama dam was constructed, it blocked the freshwater flow of water out to sea, which in turn blocked the saltwater from coming back inland. The blockage made the area a great habitat for the snails that host the schistosomiasis parasite. It increased the available habitat while also decreased some of the predators that helped keep the snail population in check, because those predators, like prawns, required both fresh and salt water for their life cycles. As a result, the snails flourished and unfortunately schistosomiasis infections followed,” she said. “This problem has been seen in countries like Egypt and China following the dam constructions projects as well.”
Wolfe said that the prevalence of schistosomiasis in school-aged children in that region range between 70 and 80 percent.
She and Dr. Jason Rohr, professor in the Department of Integrative Biology at USF, Rohr’s project manager partnered with a local NGO, Espoir Pour la Santé (“Hope for Health”), to investigate the snail habitats and determine ways to maximize disease control efforts.
“My research in particular is focusing on using remote sensing methods and high definition satellite imagery to pinpoint where the exact snail habitats are in these high-risk regions so we can better target where to implement the control measures with the limited resources that we have,” she said.
Currently, Wolfe is going through the data she collected over the summer hoping to create a remote sensing model that can predict where the snail populations are thriving.
“I don’t think that where you live should determine the quality of life you have, and unfortunately this is the case here today,” Wolfe said. “Schistosomiasis is classified as a neglected tropical disease and it doesn’t receive much funding because it usually tends to affect populations who are living in dire situations. I like to work to remedy that.”
Story by Caitlin Keough, USF College of Public Health
Tags: Caitlin Wolfe, Democratic Republic of Congo, disease control, doctoral candidate, ebola, Espoir Pour la Sante, freshwater snails, Jason Rohr, neglected infectious diseases, parasites, remote sensing, satellite, schistosomiasis, Senegal, student research, WHO, World Health Organization