Dr Stewart-Ibarra’s initial studies provided the first
evidence regarding the role of climate and social risk
factors in the transmission of dengue fever in this region
It is imperative that researchers learn all they can
about the climate events that trigger vector-borne outbreaks to
better predict and prevent epidemics
What analysis do you carry out in your laboratories in Ecuador?
We have clinical and entomology laboratories set up in Machala, Ecuador, in partnership with the Ministry of Health and the local university, the Universidad Tecnica de Machala. In the clinical laboratory, we enroll patients with suspected dengue fever, chikungunya or Zika fever in the study, then collect demographic information and a blood sample. The samples are tested for DENV, CHIKV, or ZIKV. They are then sent for further analysis, including the identification of other co-infections. For example, we’ve also screened our samples for the presence of Chagas disease (transmitted by the kissing bug) and Rickettsial diseases (transmitted by ticks).
In our entomology laboratory, we have basic mosquito rearing capabilities, and we have two experimental huts. These are replicas of local houses which are fully screened in, so that mosquitoes we release into the hut won’t escape. In the lab, we rear Aedes aegypti mosquitoes for different experiments, such as testing new mosquito control devices in the experimental huts, or testing for insecticide resistance. We also collect adult mosquitoes from homes in the community, and bring them back to the laboratory to sort by species and sex. These mosquitoes are later analysed for the presence of DENV, CHIKV, ZIKV and other viruses. How have the local communities responded to your research?
Local communities have been very receptive to our research. The work began as a grassroots research initiative, supported by Ecuadorian institutions and Ecuadorian researchers, and our research focus is driven by public health priorities in Ecuador. When I started working with urban communities in Machala during my PhD, I developed a close relationship with the community leaders. They were very receptive and were glad that we were paying attention to the broader social-ecological problems associated with dengue fever, which include access to potable water, garbage collection, housing conditions, etc.
At that time, my role as a researcher was to create a space where community leaders could have a dialogue with public health leaders, to identify their needs and develop joint solutions. Today, my role is to ensure that our research stimulates the development of new interventions that can reduce the risk of these mosquito-borne diseases. This is the nature of translational science – to move from the bench to real world solutions. What have been the most challenging aspects in carrying out your fieldwork?
One of the greatest challenges we faced was when the earthquake occurred in April 2016. My role changed dramatically from researcher to emergency responder. A 7.8 magnitude earthquake devastated the north-central coast of Ecuador, resulting in the worst natural disaster in many decades. We immediately stopped all research and relocated to the disaster area. We raised funds from the US and worked with local organisations to set up a primary care clinic and medical brigades to attend to people from the most affected communities. This required close coordination with the local Ministry of Health, the National Secretary of Risk, local religious organisations, and the Sathya Sai School.
The earthquake occurred as the Zika epidemic was sweeping through the region. Tens of thousands of people were sleeping outdoors for weeks and months, exposed to infectious mosquito bites. Water supply systems were damaged, resulting in water storage in buckets and drums, and an increase in mosquito larval habitat. People’s immune systems were suppressed because they were experiencing posttraumatic stress and losing sleep due to the recurrent aftershocks. We found that women who reported a greater number of posttraumatic stress symptoms were also more likely to report arbovirus (DENV/CHIKV/ZIKV) symptoms.
This experience fundamentally changed the way that I understood the intersection of social vulnerability, natural disasters and emerging epidemics; and the role of the scientist in times of emergency. Over one year later, this work has evolved into the NGO, Walking Palms, which is led by local volunteers David Madden and Avriel Diaz. Walking Palms continues to provide integrated health care to six communities in the city of Bahia de Caraquez. They are the only non-governmental group that has provided continuous post-earthquake health care to the communities. It will be many years before these communities recover, and long-term support is imperative. Are there any other mosquito-borne diseases that pose a threat to Latin America at the moment?
There is a major risk that malaria will re-emerge in the region. Historically, malaria was endemic and caused the greatest burden of mosquito-borne disease in southern coastal Ecuador. It was completely eliminated from the region in 2011, and in the bordering province in northern Peru in 2012. However, in 2015 we began to see a resurgence of malaria in nearby areas. As often happens, investment in malaria control and surveillance has been dramatically reduced following the reduction of transmission. Unless we are careful, the same thing will happen to malaria as happened with dengue fever, which was eradicated throughout the region in the 1950s, and re-emerged in the 1980s following the decline in vector control. What have you enjoyed most about your work in Ecuador?
I have strong personal connections to Ecuador, as I am a US-Ecuadorian citizen. This work has allowed me to bridge my passion for ecology and social justice, and to conduct research that directly addresses some of the most significant public health issues today. One of the most rewarding aspects of my work has been to see the growth and development of the research programme, from a grassroots pilot project 10 years ago, to a vibrant interdisciplinary research programme. The research platform has also provided important international training opportunities for US and Ecuadorian students, researchers, and international practitioners. Our success is due to the fact that US and Ecuadorian partners share the vision that this is a long-term partnership, with all partners contributing important roles.
Research Objectives
Dr Stewart-Ibarra aims to understand the role of climate and social vulnerability in the emergence and persistence of dengue fever, Zika and other mosquito-borne infectious diseases. Funding
Clinical Research Management (CRM); U.S. Centers for Disease Control (CDC); NSF EEID; NSF Zika Rapid; Prometeo Fellowship of the National Secretary of Higher Education, Science, Technology and Innovation (SENESCYT) of Ecuador Collaborators
Dr Mark Polhemus, SUNY Upstate Medical University; Dr Timothy Endy, SUNY Upstate Medical University; Dr Sadie J. Ryan, University of Florida; Dr Rachel Lowe, London School of Hygiene and Tropical Medicine; Dr Angel Muñoz, Princeton University; Dr Erin Mordecai, Stanford University; Dr Efrain Beltran-Ayala, Universidad Tecnica de Machala; Lic. Tania Ordoñez, Ministry of Health; Dr Mercy Silva, Ministry of Health; Dr Washington B. Cardenas, Escuela Superior Politecnica del Litoral; Dr Mercy J. Borbor-Cordova, Escuela Superior Politecnica del Litoral; Dr Marco Neira, Catholic University of Ecuador Bio Dr Stewart-Ibarra is the Director of the Latin America Research Program of the Center for Global Health & Translational Science at SUNY Upstate Medical University, and an Assistant Professor in the Department of Medicine. She received her PhD in ecology from the SUNY College of Environmental Science and Forestry and Masters in Public Administration from the Maxwell School of Citizenship and Public Affairs at Syracuse University. Stewart also received a Fulbright Fellowship from the US State Department and a Prometeo Fellowship from the Ecuadorian government to conduct research on dengue fever in Ecuador. Contact
Anna M. Stewart Ibarra, PhD, MPA;
SUNY Upstate Medical University, Syracuse, NY, USA
E: stewarta@upstate.edu