Zoonosis: How Does Population Growth Influence Animal-to-Human Pathogen Spillover?

Using the Covid-19 pandemic as an example, this class will discuss the links between human activity and zoonotic diseases. It will explore how deforestation, habitat destruction, species extinction, wildlife trade, and industrialized agriculture have contributed to zoonotic disease outbreaks by creating ideal environments for animal-to-human pathogen spillovers. The class will end by introducing the “OneHealth” approach to conservation as a potential way to stop future outbreaks.




Participant Book Recommendations

  • The Coming Plague—I recommend it!
  • Conversations with Friends—I would recommend.
  • Braiding Sweetgrass by Robin Wall Kimmerer. WONDERFUL!
  • That Wild Country—a little too macho outdoorsman for me, but an interesting intersection of hunters and environmentalists banding together for public lands
  • How to be an Antiracist.  Everyone should read.
  • The Two Lives of Lydia Bird—it was good!
  • Pardonable Lies by Jacqueline Winspear
  • In a Sunburned Country (about history and travel in Australia)—highly recommend
  • Too Much and Never Enough by Mary L. Trump—excellent.
  • The Warmth of Other Suns (about the Great Migration) by Isabel Wilkerson


What about tea crops?
Tea crops are also cash crops, for which the same economic processes apply. The main point we were trying to make is that the economic structure we’ve created on a global scale has made it so that certain countries depend on the production and sale of one or a few cash crops to support and hopefully grow their economies. In these cases, it could be argued that deforestation, habitat destruction, and exploitive land use practices are essential for economic survival. Many countries located in biodiverse, tropical regions like Brazil produce cash crops for export. This is a really complex topic that deserves its own class entirely!

Is the pandemic sending an environmental and population message to actors who count, but are not in the choir?
I think the pandemic has brought to the surface many issues that are now difficult, if not impossible, to ignore. The emissions reductions we’ve seen globally as a result of Covid-19 now have defined benefits in terms of air quality, reduced deaths, and improved health. This should  be the catalyst for increased investment in renewables. Covid-19 has also highlighted many existing disparities according to race, gender, income, and other social indicators, which should help clarify the need for integrated solutions both in response to the pandemic and for sustainable development efforts moving forward.

Can you give some more ideas of how we can translate this into local action on the scale needed?
In terms of individual contributions, I do think it’s important to consume as consciously as possible. A lot of this requires education and extensive research, as many products are advertised in misleading ways. Understanding the supply chain of goods produced far away is really difficult, but it can help paint a clearer picture regarding the origin(s) of the goods you consume on a regular basis. As much as we can, we need to be educating ourselves about the interconnections between human health, human impacts on the environment, and the health of the planet. That sounds both simple and daunting, and that’s the point! One tangible way forward is to try to buy foods that are organically grown and local. Try to familiarize yourself with your surrounding environment and what exists naturally there.

Which companies are working on this solution, and how can we support them?
There are many organizations involved in the One Health approach, including our partner organization, Conservation Through Public Health (CTPH). We talked briefly about them during the Q&A, but they are doing some really important work in the realms of gorilla conservation and sustainable development. Check out their work here: https://ctph.org.

You touch on contraception, but isn’t the unprecedented increase in population due to lack of access to contraception?
In part, yes. As we were talking about, rapid population growth is largely the result of high rates of unintended pregnancies and the inability of women to access contraceptives and reproductive health services more broadly. However, high fertility rates are also correlated with poverty and lack of access to resources, which in many ways is a reflection of social support or lack thereof. Fertility rates are high in poor regions because overall health and life expectancy is usually quite low, and the assumption is that it’s advantageous to have many children because not all will survive and because they are needed to help with household and localized labor. When public services and utilities like running water are put into communities, and when labor conditions improve, and when social safety nets increase, then fertility rates start to drop. This has a lot to do with government support.

Kamala Harris is supposed to be a real advocate of environmental justice. Is there anything in the Democratic platform that is hopeful?
The 2020 Democratic Party Platform includes six pages about “Combating the Climate Crisis and Pursuing Environmental Justice,” beginning on page 49.

Along with Alexandria Ocasio-Cortez, Kamala Harris introduced a bill a couple weeks ago called the Climate Equity Act of 2020 (no bill number available yet).

If you’re interested in population and politics, please visit the website of our sister organization, Population Connection Action Fund!

Chances of the repeal of Helms Amendment?
Now that we have, for the first time ever, a bill that would repeal the Helms Amendment, we are closer than we’ve ever been to ending this dangerous policy (which prohibits the use of U.S. foreign assistance for the performance of safe abortion). The Abortion Is Health Care Everywhere Act, introduced in late July by Rep. Schakowsky (D-IL-9), would repeal Helms and allow foreign aid to be used for abortion services, as permitted by law, in aid-recipient countries. If the pro-choice majority in the House holds in November, and the Senate gains a majority, we have an excellent chance of repealing Helms, which has been in place since 1973!

Should I donate to the Guttmacher Institute?
Guttmacher is an invaluable resource for Population Connection and for other groups that work on issues related to reproductive health, in the U.S. and in developing countries. The organization’s data and analyses help us examine trends in reproductive health over time and allow us to articulate confidently the importance of working toward universal access to reproductive health, including voluntary contraception.