Home

I am studying avian diseases as part of the Field Museum’s Emerging Pathogens Project (EPP), and am particularly interested in mapping and modeling disease distributions of avian haematozoa - blood parasites that are typically transferred to host organisms by dipteran vectors.  Haematozoa in birds (and many other organisms) are relatively understudied, and as a consequence, not much is known about their distributions, evolutionary relationships, or the factors that influence their transmission and ecological patterns.

Using samples I helped collect on Field Museum expeditions to Malawi and Peru, I am now assessing infection prevalence of avian malaria in birds and mammals. Using these data, I can ask many different questions. For example, how many species of haematozoa exist in the areas of Malawi that we sampled, and how closely related are the different species I find? Do certain genera or families of birds tend to be infected more frequently than others, and might these be related to social and behavioral patterns?

I am also interested in ecological patterns. For example, do birds living in degraded habitats suffer more frequent infection rates than their counterparts in pristine habitats? Understanding the relationship between habitat quality and disease transmission is extremely important for conservation planning, and can have important implications for humans as well. Identifying key reservoir species can help us prevent or mitigate the spread of particular diseases that can potentially threaten humans, domestic pets and livestock.

One way of describing a particular species’ role in disease transmission is by calculating something called “host reservoir competence”. Host reservoir competence is the likelihood that an individual host or host species will contract and transmit a given type of infection. It can be determined by comparing vector feeding preferences and infection rates to the number of infected hosts, the extent to which they are infected, and overall host abundance. I hope to answer these kinds of questions by collecting data both in the field and here at the Field Museum. So far, I have found using molecular techniques that birds in Malawi have approximately a 50% malarial infection rate. I am also relying on other experienced collaborators to confirm my findings via microscopy. Because molecular techniques for detecting avian haematozoa are still being improved, and because microscopic detection and identification is notoriously challenging, it is important that we take this two-sided approach. Resources in the Pritzker Lab have been instrumental in helping me improve the molecular detection methods, and I expect that any confusion encountered during this study will be resolved through these improved methods and collaboration with other researchers.

The high infection frequency of birds sampled in Malawi, combined with the fact that Malawi has a wide range of habitats of varying quality, indicate that it will be a good place to conduct this type of research. However, malaria and other haematozoa are globally distributed, and samples I collected on one of this year’s FMNH expeditions to Peru should produce interesting base-line data as well. This type of study is important for any country, particularly developing countries like Malawi or Peru, where communities are increasingly expanding their boundaries at the expense of pristine habitat and biodiversity.