Research Fellow, Dr Gladys Mosomtai, from the International Centre of Insect Physiology and Ecology (icipe), works on applying Earth observation data to better understand the spread of infectious disease in livestock, in Kenya.

Gladys is one of the first researchers to be based in ESA, under the EO AFRICA programme, which addresses the sustainable adoption of Earth Observation and related space technology in Africa, by empowering the new generation of African researchers to develop innovative and reliable evidence-based solutions, specifically for food-security and water management efforts.

Transmitted primarily by the Aedes mosquitoes, Rift Valley Fever (RVF) is the transboundary zoonotic disease she is researching, which affects both humans and animals with severe economic consequences.

Her study integrates Earth Observation (EO) and telemetry data, mosquito vectors that mainly transmit the RVF disease, and serological data, which show the exposure of the animals to RVF infection along their migratory routes, with rangeland characterisation. The research aims to fill an important gap on the role of cattle movement in the transmission and maintenance of the Rift Valley Fever virus, thus improving the early warning systems for its outbreaks supported by EO data.

Born in 1988, in Mogotio, a small town in the semi-arid part of the central Rift Valley in Kenya, Gladys grew-up in a pastoral community and already at a young age became quite aware of the environmental challenges faced by her society.

This largely formed her choice to pursue a bachelor’s degree in environmental planning and management at Kenyatta University. Furthermore, the late Prof. Wangari Maathai had just won the Nobel Peace Prize for her activism in politics and protecting the environment, becoming Gladys’ new role model.

ESA: How did your studies help you to arrive where you are today? 

Gladys Mosomtai: I was introduced to Geographic Information System (GIS) and remote sensing in one of the modules in my undergraduate programme, in 2009. At the time, it was much more theoretical, with only my professor’s computer used for practical exercises.

The exercises were projected on a screen, and I remember being fascinated by how different band combinations revealed different features on the landscape and its applicability in studying different aspects of the environment, from water resource management, to monitoring forest change and urban planning.

I decided to attend a two-week training at the Regional Centre for Mapping of Resource for Development (RCMRD), to get hands-on experience and since then, my passion for GIS and remote sensing was ignited and turned into my career.

ESA: How and when did you decide you wanted to focus on Earth Observation?

Gladys: During my undergraduate research project, I sought to understand why the water quantity and quality in the only permanent river in my hometown had gradually declined over the years. Growing up, this river was always full, and we would take the animals there to drink water, but by the time I was at university, water scarcity had become a big issue.

Using Landsat images for two epochs, I was able to show the land use and land cover changes that had occurred in the watershed and its possible contribution to the declining water quality and quantity in the river. Furthermore, I conducted interviews to understand the changes that had occurred over the years and this rigorous research experience, with funding from my parents, set me up to be the scientist I am today. I understood then the power of science—it provides solutions to societal problems, and I wanted to be a problem solver.

ESA: How did this project as Research Fellow at ESA come to life?

Gladys: My current research started while pursuing my MSc in GIS and remote sensing, at the Dedan Kimathi University of Technology, in Kenya, in 2015. I worked on it as my research project, but at the time I was not well advanced in the fields. I needed to meaningfully explore the datasets and answer the research questions at hand.

So, I paused the task and went on to pursue my PhD at the University of KwaZulu Natal, South Africa, in 2017, which focused on the landscape ecology in smallholder coffee agroecosystems and its influence on population dynamics of coffee pests. The skills gained during my PhD allowed me to better tackle my current research at ESA.

At ESA, my research focuses on linking the movement patterns of nomadic pastoralists to their exposure to Rift Valley Fever disease (RVF) along their migration routes. RVF is a zoonotic disease caused by a virus transmitted through bites by infected mosquitoes, or by coming in contact with body fluids of infected animals. The transboundary nature of the disease makes it a global risk and necessitates a holistic understanding of RVF virus transmission dynamics to strategically manage the disease, especially during outbreaks.

ESA: How are the various data you use making a difference in your work?

Gladys:

Given the interdisciplinary nature of my research, I am integrating data from (1) GPS collars (these are used to monitor cattle and track where they go) to answer the question where and when the pastoralists move in time and space, (2) Earth observation to understand the drivers of this movement and (3) serum surveys that measure the level of RVF antibodies in the collared herds, to identify where the exposure to RVF virus occurred in their migratory routes. I am leveraging on the Innovation Lab, a cloud computing platform provided by the EO AFRICA R&D Facility, to test and run my codes in Jupyterlab with access to datasets from the CREODIAS infrastructure.

Of interest to my research is generating phenology products from TIMESAT, using NDVI from medium spatial resolution EO data of various ESA missions to link movement patterns of pastoralists to pasture availability and to characterise grassland types. This especially in regions where the collared herds spent 50% of their time grazing to map forage quality and quantity during the collaring period in the study area. I envisaged that the movement patterns of pastoralists will help in identifying areas where the introduction or amplification of the disease could potentially occur, and this will contribute to the understanding of RVF epidemiology and present opportunities for strategic disease prevention securing the food security of the pastoral community in Kenya.

ESA: What does it take to succeed in a STEM (Science, technology, engineering, and mathematics) career, especially as a woman?

Gladys: : Firstly, a grit mentality; having the courage, resilience, and perseverance to go against the tide and this is often from systemic cultural and institutional barriers that have held women back for generations, and sometimes personal ambitions, which can get in the way when you have to choose between a career for instance and raising a family.

Secondly, it takes a village for a woman to succeed, especially a woman with a young family. I am a classic example; for me to be here at ESRIN, I had to leave my one-year-old son with my husband and family. Their unwavering support has accorded me peace of mind, which has allowed me to focus on my current research.

Thirdly, I have been lucky to have good mentors who have guided me in my career and to be around women who are leaders in their institutions. This has normalised my perspective on women and leadership, and I foresee myself in such positions in the near future.