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Dr Joanne Lello

Dr Joanne Lello

Senior Lecturer

School of Biosciences

+44 (0)29 2087 5885
+44 (0)29 2087 4116
Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX
Available for postgraduate supervision

My research focuses on the ecology and evolution of infectious disease, particularly, what happens when individual hosts or host populations are infected by more than one parasite at a time (coinfection). I am very interested in how common and persistent infections (endemic), like gut helminths, may alter the likelihood of epidemic diseases emerging and spreading in populations. To explore these questions, I use a combination of field and lab based studies coupled with mathematical modelling techniques.


Assessment Co-ordinator: BI2133/4 Ecology and Conservation

Module Leader: BI3156 Systems Biology and Modelling.

Interested in joining my lab as a self-funded post-graduate student or a postdoc/fellow? Please contact me by email.

I started out as a junior medical laboratory scientist in microbiology at Liverpool PHLS, but returned to education undertaking an Applied Biology degree at Liverpool John Moores University. Following my degree I spent several years studying squirrel behaviour and disease before taking up a PhD in December 1999 at Stirling University under the guidance of Prof. Peter Hudson. It was there that my interest in coinfection began while studying the "Community Ecology of Rabbit (Oryctolagus cuniculus) Parasites". After completion of the PhD in May 2006 I moved to Armidale (NSW, Australia), to take up a position as a Research Scientist in CSIRO Livestock Industries extending my coinfection research to examine the immune mechanisms mediating parasite interspecific interactions in sheep. Finally after three years down-under I returned to the UK and gained my position as a Lecturer here in Cardiff, where I became a Senior Lecturer in 2014.














Year 2: Week long practical (An Exploration of Individual and Environmental Health: An Exercise in Data Handling, Analysis and Visualisation)

Masters of Research (MRes): BIT010  Data Handling and Statistics

SWBIO GW4 PhD: statistics.

Current and developing research

The role of parasites in sexual selection

One of the key unanswered questions in the field of sexual selection is 'What are the costs and benefits (for both sexes) of female mate choice?'  Importantly, environment, including the risk of infection, can alter the costs of mate choice. Alternatively, parasites may alter the choice itself. We are exploring the role of parasites using two model insect species (Lobster cockroaches and German cockroaches), that have different types of mating cost. Lobster cockroaches provide only indirect benefits of mate choice (i.e. the female does not live longer or produce more offspring if she mates) whereas the German cockroach provides direct benefit to the female by providing a nuptial gift (food) during mating (which may then increase female survival or the number of offspring she can produce). Both cockroach species carry endemic gregarine infections in their gut and our preliminary work suggests theses parasites may be important in mate selection.

How important is coinfection to human health?

We are all assaulted simultaneously by a plethora of different infectious organisms. This is especially true for people living in the developing world, where endemic infections are common and multiple infections are the norm. In recent work ( we demonstrated that infection with one species could alter the risk of being infected with another species. We continue to explore this question considering how coinfection may influence disease severity and infection and transmission processes using field studies combined with statistical methodologies.

What is the role of coinfection in the emergence, transmission and evolution of epidemic disease?

The German cockroach (Blattella germanica) is host to an endemic gut parasite, Gregarina blattarum. We use this model system to determine whether and how this endemic species alters the spread and evolution of an epidemic parasite species Steinernema carpocapsae. We have demonstrated that within host competition for resources between the endemic and epidemic parasites leads to a substantial reduction in transmission potential of the epidemic species ( In our ongoing work we are assessing whether these within host processes scale up to effect changes in epidemic spread through populations. We also aim to explore whether the within and / or between host processes result in the evolution of greater virulence in either parasite species or in the evolution of host resistance mechanisms.

Immune responses during coinfection

There are many different arms to the immune response and these different components often interact, up or down regulating one another. Therefore, the response of a host to one parasite species may have profound effects upon how that host responds to a second species. I am exploring this idea in both vertebrate and invertebrate systems. In past work with CSIRO I demonstrated that the blood feeding helminth Haemonchus contortus suppresses host immune response against a second helminth species Trichostrongylus columbriformis, in sheep (work in prep for publication). In my current work I am using the cockroach system to assess how macro- and micro-parasites may interact through differential host immune responses.

Can we define coinfection functional groups?

In classical ecology we can define organisms in a particular environment by their effect upon and response to that environment – the functional group. Organisms can often be assigned to functional groups based on simple characteristics. Potential interactions between species can then be inferred by understanding how the functional groups interact rather having direct knowledge of the two species. If we can use this idea to group parasites we can potentially predict how any two parasite species might interact ( Ongoing work using a variety of systems explores this concept, in particular with respect to the immune axis (i.e. using immune responses as a mechanism by which to group parasites).

Additional information

I am Chair of the British Ecological Society Special Interest Group: Parasite and Pathogen Ecology and Evolution. This group brings together a current membership of over 230 researchers, at all career levels, from across the UK and is now expanding its membership into Europe and further afield. The aim of the group is to:

  • be a central forum for parasite and pathogen ecologists and evolutionary biologists to make and maintain contacts, exchange and discuss ideas and promote useful events. As a part of this aim the group will play a role in encouraging early career development
  • seek collectively to understand the causes of variation in parasite-host interactions with a focus on the ecological and evolutionary influences
  • form a coherent body of scientists who can act as a force to inform government policy on funding, conservation and health with respect to parasites and pathogens
  • to evolve according the ideas and needs of its membership.

Cardiff Research into Infection, Parasites and Ecological Systems (CRIPES)

I am a member of CRIPES, which is a research group within the Organisms and Environment Division in the School of Biosciences at Cardiff. This diverse group link through the study of the ecology of infectious diseases.

Research grants

  • 2015-2016 Marie Skłodowska-Curie Actions Fellowship (H2020-MSCA-IF-2014; grant no. 661690) “PARACORT:  The role of macroPARAsite COinfection in Rodent-borne microparasite Transmission” at the Fondazione Edmund Mach, Italy.
  • 2007-2011: Natural Environmental Research Council studentship (NERC; NE/G523420)
    Endemic infection in the German cockroach, Blattella germanica. – Joanna Randall
  • 2007-2008: Cardiff University Seed Corn Funding
    Co-infection dynamics in a free-running system using the cockroach host (Blattella germanica).
  • 2004-2007: CSIRO Livestock Industries, Australia
    Complex systems science approaches to sheep gut helminth interactions.

Recent publication

Theme issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission' compiled and edited by Joanne Lello and Andy Fenton (Philosophical Transactions of the Royal Society B) 10.1098/rstb/372/1719

Major collaborators

Prof Mark Viney University of Bristol, School of Biological Sciences

Prof Viney is a parasite biologist interested in all aspects of developmental control. He also has a particular interest in the immune response to parasites and the response of the parasites themselves to the host immunity. We collaborate on projects concerning parasite coinfection, in particular with relation to detection and human health.

Dr Mark Viney

Dr Mhairi Gibson  University of Bristol, School of Arts

Dr Gibson is a biological anthropologist focusing on applying evolutionary ecology to emerging public health and social issues in low income settings. She combines qualitative anthropological and quantitative demographic methodologies with the theoretical frameworks of evolutionary biology.

Dr Mhairi Gibson

Prof Rachel Norman University of Stirling, Department of Mathematics and Department of Evolutionary and Environmental Biology

Prof Norman is a mathematician focused on modelling infectious disease dynamics and control. We have published three papers together including the recent publication detailed above which explores and alternative strategy for describing transmission in mathematical models.

Prof Rachel Norman

Prof Jürg Utzinger: Swiss TPH, Epidemiology and Public Health

Dr Utzinger is a Professor of epidemiology with a focus on the diagnosis, epidemiology and control of neglected tropical diseases, particularly schistosomiasis, soil-transmitted helminthiasis and food-borne trematodiasis. In particular I have published with Prof Utzinger on the role of coinfection in disease risk of school-aged children in Tanzania.

Dr Jürg Utzinger

Prof Andrew Fenton: Liverpool University, School of Biological Sciences

Dr Fenton is an ecologist and mathematical modeller with particular interests in the epidemiology and evolution of parasites. I have collaborated with Dr Fenton on a number of projects and we have published five papers together.

Dr Andrew Fenton