Many questions remain unanswered about the role of microbial transmission in epizootic shell disease in American lobsters (Homarus americanus).

Lobsters are an iconic part of Maine culture, from cuisine to interior decorating to way of life. The Gulf of Maine boasts large lobster landings every year, but as the waters here continue to warm at a faster rate than other nearby coastal regions, there are concerns that this boon might eventually pass us by as lobsters migrate further north in search of colder waters. In addition to rising temperatures along the northeastern coast, we’ve seen an increase in epizootic shell disease (ESD) in the last few decades. ESD causes degradation and pitting of the lobster shell which can leave them susceptible to predation or to harsh weather conditions. There are bacteria living on the shell of healthy lobsters, and it’s not clear how they are involved in ESD in the wild because it is difficult to replicate this disease in an aquaculture facility.

In this perspective piece, we consider how shell microbes might be involved. Marine environments have a thriving microbial community which can change rapidly when currents, storms, filter feeders, or viruses which target microbes roll through. Some of these water or soil microbes end up on lobster shells, and water currents can also lift microbes off and move them elsewhere. The other authors and I wanted to highlight some of these possibilities and what we still don’t know about lobster microbes and health.

A steamed lobster on a plate.

This perspective piece is part of a larger, collaborative project on lobster shell disease and warming ocean waters was begun by researchers at the Aquaculture Research Institute: Debbie Bouchard, Heather Hamlin, Jean MacRae, Scarlett Tudor, and later Sarah Turner as a grad student. I was invited to participate in the data analysis aspect two years ago.

At the time, Grace Lee was a rising senior at Bowdoin College, and accepted to my lab for the UMaine REU summer 2020 session, which was canceled. Instead, I hired Grace to perform DNA sequence analysis remotely, by independently learning data analysis following the teaching materials I had generated for my sequencing class.  I invited Joelle Kilchenmann to this piece after a series of conversations about microbes and social equity, because her graduate work in Joshua Stoll’s lab focuses on lobster fishing communities in Maine and understanding the challenges they face.


Ishaq, S.L., Turner, S.M., Tudor, M.S.,  MacRae, J.D., Hamlin, H., Kilchenmann, J., Lee1, G., Bouchard, D. 2022. Many questions remain unanswered about the role of microbial transmission in epizootic shell disease in American lobsters (Homarus americanus). Frontiers in Microbiology 13: 824950.

This was an invited contribution to a special collection: The Role of Dispersal and Transmission in Structuring Microbial Communities

Abstract: Despite decades of research on lobster species’ biology, ecology, and microbiology, there are still unresolved questions about the microbial communities which associate in or on lobsters under healthy or diseased states, microbial acquisition, as well as microbial transmission between lobsters and between lobsters and their environment. There is an untapped opportunity for metagenomics, metatranscriptomics, and metabolomics to be added to the existing wealth of knowledge to more precisely track disease transmission, etiology, and host-microbe dynamics. Moreover, we need to gain this knowledge of wild lobster microbiomes before climate change alters environmental and host-microbial communities more than it likely already has, throwing a socioeconomically critical industry into disarray. As with so many animal species, the effects of climate change often manifests as changes in movement, and in this perspective piece, we consider the movement of the American lobster (Homarus americanus), Atlantic ocean currents, and the microorganisms associated with either.


Related presentations

Ishaq*, S.L., Lee, G., MacRae, J., Hamlin, H., Bouchard, D. “The effect of simulated warming ocean temperatures on the bacterial communities on the shells of healthy and epizootic shell diseased American Lobster (Homarus americanus).” Ecological Society of America 2021. (virtual). Aug 2-6, 2021. (accepted talk)

Ishaq*, S.L., Lee, G., MacRae, J., Hamlin, H., Bouchard, D. The Effect Of Simulated Warming Ocean Temperatures On The Bacterial Communities On The Shells Of Healthy And Epizootic Shell Diseased American Lobster (Homarus americanus)ASM Microbe/ISME World Microbe Forum 2021 (virtual). June 20-24, 2021. (poster)

Framing the discussion of microorganisms as a facet of social equity

In just a four-week course in 2019 when I was working at the University of Oregon, I introduced 15 undergraduates from the UO Clark Honors College to microorganisms and the myriad ways in which we need them. More than that, we talked about how access to things, like nutritious foods (and especially fiber), pre- and postnatal health care, or greenspace and city parks, could influence the microbial exposures you would have over your lifetime. Inequalities in that access – such as only putting parks in wealthier neighborhoods – creates social inequity in resource distribution, but it also creates inequity in microbial exposure and the effect on your health.

By the end of the that four weeks, the students, several guest researchers, and myself condensed these discussions into a single paper (a mighty undertaking, indeed). Interest in this paper sparked the formation of the Microbes and Social Equity working group.

During the course, a number of guest lecturers were kind enough to lend us their expertise and their perspective:


Ishaq, S.L., Rapp, M., Byerly, R., McClellan, L.S., O’Boyle, M.R., Nykanen, A., Fuller, P.J., Aas, C., Stone, J.M., Killpatrick, S., Uptegrove, M.M., Vischer, A., Wolf, H., Smallman, F., Eymann, H., Narode, S., Stapleton, E., Cioffi, C.C., Tavalire, H..  2019Framing the discussion of microorganisms as a facet of social equity in human health. PLoS Biology 17(11): e3000536.

Abstract

What do “microbes” have to do with social equity? These microorganisms are integral to our health, that of our natural environment, and even the “health” of the environments we build. The loss, gain, and retention of microorganisms—their flow between humans and the environment—can greatly impact our health. It is well-known that inequalities in access to perinatal care, healthy foods, quality housing, and the natural environment can create and arise from social inequality. Here, we focus on the argument that access to beneficial microorganisms is a facet of public health, and health inequality may be compounded by inequitable microbial exposure.

Framing the discussion of microorganisms as a facet of social equity in human health

In summer 2019, I developed and taught a course on ‘Microbes and Social Equity‘ to the Clark Honors College at the University of Oregon.

In just a four-week course, I introduced 15 undergraduates from the University of Oregon Clark Honors College to microorganisms and the myriad ways in which we need them. More than that, we talked about how access to things, like nutritious foods (and especially fiber), per- and postnatal health care, or greenspace and city parks, could influence the microbial exposures you would have over your lifetime. Inequalities in that access – such as only putting parks in wealthier neighborhoods – creates social inequity in resource distribution, but it also creates inequity in microbial exposure and the effect on your health.

The course assignments were literature review essays on various topics, which were compiled into a single manuscript as the group-based final project for the course. This large version is available as a preprint; however, the published version is more focused (abstract below). Course materials are here.

What is next for ‘Microbes and Social Equity’?

Since publishing in November, a number of researchers have connected with me, and we have formed a loose collaboration for “Microbes and Social Equity Part 2”. We have several initiatives in development, and there will be news releases as those coalesce. At this time, we are developing a journal special call, and a series of workshops/mini-symposia, both with the goal of connecting researchers and practitioners. Stay tuned!


Framing the discussion of microorganisms as a facet of social equity in human health.

Suzanne L. Ishaq1,2*, Maurisa Rapp2,3, Risa Byerly2,3, Loretta S. McClellan2, Maya R. O’Boyle2, Anika Nykanen2, Patrick J. Fuller2,4, Calvin Aas2, Jude M. Stone2, Sean Killpatrick2,4, Manami M. Uptegrove2, Alex Vischer2, Hannah Wolf2, Fiona Smallman2, Houston Eymann2,5, Simon Narode2, Ellee Stapleton6, Camille C. Cioffi7, Hannah Tavalire8

  1. Biology and the Built Environment Center,  University of Oregon
  2. Robert D. Clark Honors College, University of Oregon
  3. Department of Human Physiology, University of Oregon
  4. Charles H. Lundquist College of Business, University of Oregon
  5. School of Journalism and Communication, University of Oregon
  6. Department of Landscape Architecture, University of Oregon
  7. Counseling Psychology and Human Services, College of Education, University of Oregon
  8. Institute of Ecology and Evolution, University of Oregon

Abstract

What do ‘microbes’ have to do with social equity? On the surface, very little. But these little organisms are integral to our health, the health of our natural environment, and even impact the ‘health’ of the environments we have built. Early life and the maturation of the immune system, our diet and lifestyle, and the quality of our surrounding environment can all impact our health. Similarly, the loss, gain, and retention of microorganisms ⁠— namely their flow from humans to the environment and back⁠ — can greatly impact our health and well-being. It is well-known that inequalities in access to perinatal care, healthy foods and fiber, a safe and clean home, and to the natural environment can create and arise from social inequality. Here, we focus on the argument that access to microorganisms as a facet of public health, and argue that health inequality may be compounded by inequitable microbial exposure.


In the Media

  1. ” UMaine prof: Inequity is creating a gut microbe gap.” Mike Tipping and Ben Chin, Maine People’s Alliance. Dec 20, 2019.
  2. Inequity takes a toll on your gut microbes, too.” Sue Ishaq,  The Conversation, Dec 4, 2019.
    1. Picked up by The Telegraph, Alton, Illinois, and other agencies
    2. Included on UMaine news
  3. All people have a right to healthy gut microbes.” Paige Jarreau and Signe Asberg, Lifeapps. Dec 3, 2019.  
  4. Rich People Have Access to Better Microbes Than Poor People, Researchers Say.” Becky Ferreira, Vice. Nov 26, 2019.
  5. Microbiome is a Human Right.” Heather Smith, Sierra. Nov 26, 2019.
  6. Life, liberty—and access to microbes?” Press release for Plos Biology. Nov 19, 2019.

Story picked up by (non-exhaustive list)