Prediction and preparedness against emerging zoonotic infections
Convener: Magnus Evander, Department of Clinical Microbiology, Umeå University
Contact: magnus.evander@umu.se
General aim: To increase preparedness against emerging zoonotic infections.
Specific aims: To determine the drivers of emerging zoonotic infections; to understand the role of the local community in outbreaks; to characterize the multidisciplinary factors needed for preparedness; to discuss the global importance of cooperation regarding combatting emerging zoonotic infections.
Emerging infectious diseases, particularly zoonoses that are transmitted from animals or vectors to humans, represent a significant threat to global health. Developing countries in Africa suffer most from the zoonotic and vector-borne disease burden and its socioeconomic consequences.
Transmission of zoonotic diseases has increased worldwide in recent years due to transboundary transport, travel, and increasingly intense livestock production in areas of proximity to human populations. An emerging infection could affect both humans and animals with an effect on the society.
Sudden emerging disease outbreaks cause direct suffering, and leads to severe negative impact on economy, exaggerating poverty to already deprived communities. Furthermore, these diseases are prone to transboundary spread and can cause new outbreaks globally.
Recent outbreaks of zoonotic infections such as Zika, Ebola, Rift Valley fever and Dengue has severely affected populations in resource poor settings. Furthermore, livestock infection could e.g. cause abortions and death in herds used for meat and dairy production and generation of income. This results in less food availability and curtailed monetary income, with major impact on poorer communities that do not have access to alternative sources of livelihood.
To improve the capacity to predict and be prepared against the impact of such emerging disease outbreaks, translational research is crucial to counteract these types of devastating outbreaks, and is the best strategy towards the prevention and control. Furthermore, cultural and equality factors (gender, community) could affect appearance and consequences of disease outbreaks. Multidisciplinary research is needed to better predict and prepare against emerging zoonotic infections as well as to guide policy makers how to develop the needed infrastructure.
Questions to be addressed
What are the drivers of emerging zoonotic diseases? With focus on understanding cultural factors. What is the future of emerging zoonoses according to the ongoing drivers (possible scenarios)?
What is the societal and economic impact of zoonotic outbreaks? (local level, country level, regional level and global level).
How should one build the capacity of local communities to prevent and control emerging zoonotic outbreaks? How should one develop a policy that considers local community as main stakeholders in the fight against emerging zoonoses. What is the expected role of developed countries in assisting developing countries regarding these aspects?
Why is One Health multidisciplinary research needed to confront emerging zoonotic outbreaks? Examples? What types of research could be suggested to fill the gap?
24 Aug., 09:00–10:30, Seminar Room Y22
- Disrupting emerging zoonotic diseases with global concern at the frontline of local community. The case of Rift Valley fever outbreaks. Osama Ahmed Hassan, Umeå University / Public Health Institute, Sudan / Umeå University; Hippolyte Affognon, Joacim Rocklöv, Umeå University; Peter Mburu, International Centre of Insect Physiology and Ecology; Rosemary Sang, International Centre of Insect Physiology and Ecology; Clas Ahlm, Umeå University and Magnus Evander, Umeå University.
- Early detection of waterborne diseases by detecting genetic traces from hosts and parasites in water samples. Micaela Hellström, Stockholm University.
- Linking cattle movement with environmental characteristics in understanding Rift Valley Fever virus transmission and maintenance along their trajectory routes. Gladys Mosomtai, International Centre of Insect Physiology and Ecology / Dedan Kimathi University of Technology; Magnus Evander, Umeå University; Per Sandström, Swedish University of Agricultural Sciences (SLU); Clas Ahlm, Umeå University; Rosemary Sang, International Centre of Insect Physiology and Ecology; Osama Ahmed Hassan, Umeå University; Charles Mundia, Dedan Kimathi University of Technology; Jacqueline Kasiiti, Ministry of Agriculture Livestock and Fisheries, Kenya; Murithi Mbaabu, Ministry of Agriculture Livestock and Fisheries, Kenya and Tobias Landmann, International Centre of Insect Physiology and Ecology.
- Entomological indices and ecology for the dengue vector in Kenya. Sheila Agha, International Center of Insect Physiology and Ecology / University of Pretoria; Tchouassi, International Center of Insect Physiology and Ecology; Bastos, University of Pretoria and Sang, International Center of Insect Physiology and Ecology.
Abstracts
Disrupting emerging zoonotic diseases with global concern at the frontline of local community. The case of Rift Valley fever outbreaks. Osama Ahmed Hassan, Umeå University / Public Health Institute, Sudan / Umeå University; Hippolyte Affognon, Joacim Rocklöv, Umeå University; Peter Mburu, International Centre of Insect Physiology and Ecology; Rosemary Sang, International Centre of Insect Physiology and Ecology; Clas Ahlm, Umeå University and Magnus Evander, Umeå University.
Background: Rift Valley fever (RVF) virus is an emerging mosquito-borne disease with potential for global expansion. It causes hemorrhagic fever in livestock and humans, with a high case fatality. There is no specific treatment or vaccine for humans and the virus has a complex transmission cycle. Innovative strategies are needed to disrupt RVF outbreaks at the frontline of occurrence at local areas. Thus, we investigated the role of the local community using the Sudan 2007 RVF outbreak as a case study. Methods: A cross-sectional community-based study using random sampling technique was conducted in Sudan. A one health questionnaire was developed to compile data from 235 households concerning humans, animals, and the environment. Findings: The participants were aware of RVF, but few had appropriate knowledge of disease symptoms and risk factors. The community was hesitant in notifying the authorities about RVF infection in livestock. RVF awareness significantly increased in subjects who were educated (P=0.02), and who used social networks for information (P=0.001). Seeking medical treatment was significantly associated with receiving RVF information from these networks (P=0.001). Interpretation: The perceived role of the community in controlling RFV was fragmented, and lack of knowledge about RVF increases the probability of global dispersal and prevents the local community from confronting the disease at the frontline. Policies enforcing disruption of RVF at the interface between humans, animals, and the environment is paramount and would benefit from targeting of the local community, their socio-cultural practices, and their education using social networks.
Early detection of waterborne diseases by detecting genetic traces from hosts and parasites in water samples. Micaela Hellström, Stockholm University.
Schistosomiasis, also called bilharzia, is an infectious disease caused by snail-mediated trematodes leading to chronic infection and high morbidity. This affects more than 230 million people worldwide in tropical and subtropical regions. In May 2012, WHO proposed a strategy to eliminate schistosomiasis. However, prevention efforts have mainly focused on drug development, and existing diagnostic methods are inefficient and unreliable. For successful elimination of schistosomiasis it is crucial to identify habitats where transmission takes place. Traditional inventory studies to detect the vector snails and their parasites are slow, expensive and unprecise. We successfully modified and used a new, feasible and innovative technique in ten inter-connected ponds in Kenya for fast and precise detection of the parasite Schistosomiasis mansoni and its snail host Biomphalaria pfeifferi. The technique called aquatic environmental DNA or eDNA builds on the following principle: Any organism within a water body leaves traces of extracellular DNA in their surroundings (eDNA). By processing 1L of water it is possible to find the DNA “fingerprints” of all species present. Because the schistosome parasites spend part of their life in freshwater, either as free living larvae or inside vector snails, they contribute to the pool of eDNA. This enables surveys covering large geographic areas within a short timeframe. To inform and include local people, collections of samples have been part of successful community projects. eDNA can target any species of choice making it applicable for surveying a wide range of waterborne zoonotic diseases, soon after spreading to a new environment.
Linking cattle movement with environmental characteristics in understanding Rift Valley Fever virus transmission and maintenance along their trajectory routes. Gladys Mosomtai, International Centre of Insect Physiology and Ecology / Dedan Kimathi University of Technology; Magnus Evander, Umeå University; Per Sandström, Swedish University of Agricultural Sciences (SLU); Clas Ahlm, Umeå University; Rosemary Sang, International Centre of Insect Physiology and Ecology; Osama Ahmed Hassan, Umeå University; Charles Mundia, Dedan Kimathi University of Technology; Jacqueline Kasiiti, Ministry of Agriculture Livestock and Fisheries, Kenya; Murithi Mbaabu, Ministry of Agriculture Livestock and Fisheries, Kenya and Tobias Landmann, International Centre of Insect Physiology and Ecology.
Rift Valley Fever (RVF) is a zoonotic disease endemic to Africa, however in recent years it is increasingly recognized as a major transboundary disease threat. Livestock movement is one of the means of spread of the disease. This study aims at characterizing this movement and understanding the exposure to RVF virus along their GPS mapped grazing routes. Cattle trajectories from 11 herds collared between June 2012 to date were analyzed and GPS-tracks overlaid on high resolution images of Google earth. The results were related to seroprevalence data sampled along the migratory routes. All herds showed limited movement during rainy season which is between March to June and November to December, while during dry season which is between January to February and July to October they covered an average of 120km in 10 days in search of pasture. Herds collared along Tana River and Garissa spent three months in Tana delta, Korini and Mboni forest while another herd collared in Isiolo spent three months in Lewa conservancy during dry season. Merti herd spent over six months both dry and wet season grazing in large wetland in Ewaso Nyiro river. Animal seroprevalence varied between wet and dry season. It also varied depending on the herd. In general we could show that there is an interepidemic activity of RVFV in these regions and that there were more positive after spending time in wet areas and during rainy season. This infection could spread to new regions when viremic cattle move long distances.
Entomological indices and ecology for the dengue vector in Kenya. Sheila Agha, International Center of Insect Physiology and Ecology / University of Pretoria; Tchouassi, International Center of Insect Physiology and Ecology; Bastos, University of Pretoria and Sang, International Center of Insect Physiology and Ecology.
Recent outbreaks of Dengue (DEN) have been reported in Kenya. The disease vector Aedes aegypti is highly domesticated and thrives in artificial water containers. Despite the emergence of the disease, studies to estimate larval indices and characterize the ecology of the vector for targeted vector control in major Kenyan cities are limited. In this study we estimated the house index (HI) and characterized positive container types for the DEN vector, Ae. aegypti, in two Kenyan cities-Kisumu and Mombasa. Houses were randomly selected and indoor containers surveyed for mosquito larvae/pupae, reared to adults and morphologically identified. The container types positive for Ae. aegypti in each house were characterized and the house index (HI) was compared between sites and seasons using chi-square. 200 houses were surveyed per site and the HI was significantly higher in Mombasa compared to Kisumu (X2 = 4.79, df = 1, p = 0.03). HI was higher during the long than the short rainy season for both sites although not significantly different. Positive containers in houses were mostly, plastic drums, metal drums, and jerry cans in Mombasa and plastic drums, Jerry cans and clay pot in Kisumu. The overall HI for Kisumu (14.0%) and Mombasa (23.0%) are indicative of high DEN transmission risk compared to the threshold (>5%) established by the Pan American Health Organization. Assessment of the competence of the vector populations is required which is ongoing. The preferred breeding containers were common for both sites and can inform the basis for possible targeted vector control.
