The epidemiology and invasive biology of pathogenic nematode Angiostrongylus cantonensis on the Balearic Islands

The invasive nematode Angiostrongylus cantonensis, the rat lungworm, is the main etiological agent of eosinophilic meningitis. Neural angiostrongiliasis is an emerging gastropod-borne zoonosis, being severely debilitating with high fatality rate, that has been steadily expanding in the world since the 1950s.  From ingestion of infective larvae, around 3000 human infections have been reported in 30 countries worldwide and the parasite is continuing to expand into naïve countries.

Europe was considered non-endemic for this snail-borne disease until, in October 2018, this nematode infection was reported in Erinaceidae in the Balearic Islands (Spain). Of note in Spain (as in most of the southern European countries), edible snails (Helix spp.) are an important part of the local cuisine, which raises food safety concerns and complex social challenges. This PhD project is presented in collaboration with scientists from LSTM, Lancaster and the Balearic Islands to explore important aspects of the epidemiology and invasive biology of this parasite adopting a “ONE Health” approach.

This proposed project aims to:

1. determine the spread and spatio-temporal ecozone of A. cantonensis on Mallorca by conducting (molecular) surveillance in gastropod hosts and small mammals and spatiotemporal analyses of environmental drivers and hotspots.

2. design optimised diagnostic techniques (involving statistical pooling approaches) allowing more rapid monitoring of this parasite in gastropod hosts across high risk areas and potential routes of diffusion within revised spatial sampling frames. 

3. address public concerns regarding angiostrongyliasis, by establishing efficient protocols for communication, prevention, diagnosis and addressing current media distortions.

The 3-year period of training seeks to identify micro-foci within small mammals, acting either as permissive or paratenic hosts. In so doing we hope to define putative disease hotspots, to elucidate seasonality effects and to understand how quickly the disease could spread across an ecozone. We therefore seek to help establish an efficient surveillance program in newly invaded areas such as the Balearics which will help Spain better prepare for any human outbreak scenario.

Where does the project lie on the Translational Pathway?

T1 (Basic Research) + T3 (Evidence into Practice)

Expected Outputs

This study will provide important information that will be used by local and European authorities to prevent human infections by A. cantonensis. After the completion of this PhD project (3-year period), this project would;

 

  1. Provide information on the life cycle of A. cantonensis in the Mediterranean region and the hosts that harbour this parasite in the south of Europe with spatial predictions of habitat invasions
  2. Provide epidemiological information on the prevalence hotspots of the rat lungworm in the Balearic Islands and define optimal sampling frameworks to identify any zoonotic transmission micro-foci
  3. Contribute to the understanding of the speed of the spread of A. cantonensis in a recently invaded area and the risk of food borne transmission to humans or other companion animals
  4. Critically evaluate the best cost-effective PCR-based diagnostic alternative for the surveillance of A. cantonensis in invertebrate hosts with effective pooled sampling designs verified by simulation
  5. Develop best practices to communicate public health information on neural angiostrongyliasis to help anticipate the public reaction to a local outbreak and its potentially detrimental effects on tourism.
  6. Assist agricultural industries (snail farmers, lettuce growers) to implement preventative measures to reduce the risk of A. cantonensis transmission to humans

 

We are expecting to publish the results of this study in international scientific journals specialized in Parasitology and Tropical Medicine (PLoS NTDs, Parasites & Vectors, etc).

 

Training Opportunities

Lancaster/LSTM provides a unique programme of training opportunities, events and seminars (updated each semester) to encourage students to meet other researchers from a wide range of specialities to grow their network. Both institutes utilises innovative Technology Enhanced Learning initiatives to ensure that students working in the field are able to interact as fully as possible with training sessions. The full catalogue of MSc modules delivered at LSTM/Lancaster are available for study and students can attend lectures and seminars.

 

In the Balearic Islands, the student will receive the following training: 1. Animal sampling strategies: sampling methods designed for disease surveillance, trap sampling methods and animal processing (snails and small vertebrates) 2. Necropsy of confirmed and suspected vertebrate hosts, 3. Pathogen isolation and processing in a biosecurity level 2 laboratory and 4. Parasite diagnosis.

 

Allied with the supervisors will have the mentorship support of Dr Lee Haines (communications), Dr James LaCourse (fieldwork) and Dr Lucas Cunningham (molecular diagnostics).

 

Skills Required

The potential candidate would require a high-quality degree in Life Sciences (Biology, Veterinary, and Medicine), basic knowledge on molecular biology and parasitology and have good communication skills in English. Interests in statistical analyses, coding (in one of Phyton, R, linux) and GIS-RS would be an advantage. Previous experience in public engagement activities or working with diverse audiences would be beneficial.  The PhD candidate is expected to be highly motivated in this field of research.  Basic knowledge in Spanish language would be valued but is not essential.

 

Key Publications associated with this project

Paredes-Esquivel C,  Sola  J,  Delgado-Serra  S,  Riera  MP,  Negre  N,  Miranda  MA, Jurado-Rivera JA 2019. Angiostrongylus cantonensis in North African hedgehogs as vertebrate hosts, Mallorca, Spain, October 2018. Eurosurveillance  24:  2-6.  doi: 10.2807/1560-7917.es.2019.24.33.1900489

Garcia-Salguero, Alejandro; Delgado-Serra, Sofía;Sola, Jessica; Negre, Nieves; Miranda,  MiguelAngel; Paredes-Esquivel, Claudia*. 2019.Combined morphology and DNA-barcoding to identify Plagiorhynchus cylindraceus cystacanths in Atelerix algirus. Parasitology Research. 118:5.

Sedda L, Lucas ER, Djogbenou LS, Edi AVC, Egyir-Yawson A, Kabula BI, et al. Improved spatial ecological sampling using open data and standardization: an example from malaria mosquito surveillance. Journal of the Royal Society Interface. 2019;16(153). doi: 10.1098/rsif.2018.0941. PubMed PMID: WOS:000466431900008.

Cunningham LJ, Stothard JR, Osei-Atweneboana M, Armoo S, Verweij JJ, Adams ER. Developing a real-time PCR assay based on multiplex high-resolution melt-curve analysis: a pilot study in detection and discrimination of soil-transmitted helminth and schistosome species. Parasitology. 2018;145(13):1733-8. doi: 10.1017/s0031182018001361. PubMed PMID: WOS:000447727700010.

Amoah AS, Hoekstra PT, Casacuberta-Partal M, Coffeng LE, Corstjens P…Stothard JR et al. Sensitive diagnostic tools and targeted drug administration strategies are needed to eliminate schistosomiasis. Lancet Infectious Diseases. 2020;20(7):165-72. doi: 10.1016/s1473-3099(20)30254-1. PubMed PMID: WOS:000544572300004.

Deadline: Thursday 11th February 2021; 12:00 noon GMT

Further details on the MRC/DTP and CASE programmes and application guidance and process can be found here