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Dr Joanne Lello  -  PhD


Current and Developing Research

 1.    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 (http://dx.doi.org/10.1098/rspb.2012.2813) 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. 

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

Photo of adult female cockroach with fully formed ootheca protruding

Adult female cockroach with fully formed ootheca protruding

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 (http://dx.doi.org/10.1098/rspb.2013.1500). 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.

3.    Immune responses during coinfection

Photo of Merino sheep, hosts to the blood feeding worm Haemonchus contortus and intestinal browser Trichostrongylus colubriformis

Merino sheep, hosts to the blood feeding worm Haemonchus contortus and intestinal browser Trichostrongylus colubriformis

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.

4.    Can we define coinfection functional groups?

Photo of Gregarine mating pairs tightly packed together after removal from a heavily infected cockroach

Gregarine mating pairs lie tightly packed together after removal from a heavily infected cockroach

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 (http://dx.doi.org/10.1017/S0031182008000383). 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).

Personal Background:

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.

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 are 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, http://cripescardiff.co.uk/ 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

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.

Major Collaborators

Dr Mark Viney: University of Bristol, School of Biological Sciences

Dr 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 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. In have collaborated with Dr Fenton on a number of projects and we have published five papers together.

Dr 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 Michael Bonsall: Oxford University, Department of Zoology

Dr Bonsall is a mathematical biologist with a focus on population biology (population dynamics, community ecology, evolutionary ecology). His research considers a wide range of questions including the population and evolutionary dynamics of parasites and host resistance. He combines modelling with empirical studies to achieve his research goals. Dr Bonsall is collaborating in fitting models to the population data from the cockroach empirical system in my laboratory.