Climate change causes zoonotic disease, and pandemics result from destruction of animal ecosystems.

The claim has two parts: (a) climate change causes zoonotic disease; (b) pandemics are due to human destruction of animal ecosystems, which brings animal pathogens into contact with livestock and humans. Judge both against the scientific consensus as of Oct 2022 (WHO, IPBES 2020 pandemics report, peer-reviewed reviews). True: the consensus supports both as causal drivers. Mostly true: both are recognised drivers, but the claim slightly overstates them, for example by stating as a sole cause something that is a major contributing factor. Mixed: one part is well supported and the other is clearly unsupported or overstated. Mostly false: both are framed as established sole causes when the evidence shows only contributing roles or unproven links (for example climate as a risk amplifier rather than a cause, and many pandemics with other origins). False: the evidence shows that neither link exists.

Set before the research began.

1. E1 Climate change increases cross-species viral transmission risk - Nature Nature (Springer Nature), by Carlson, Albery, Merow et al. · 28 April 2022

   “In some cases, this will facilitate zoonotic spillover—a mechanistic link between global environmental change and disease emergence.”

2. E2 Climate change increases cross-species viral transmission risk - Nature Nature (Springer Nature), by Carlson, Albery, Merow et al. · 28 April 2022

   “Here we simulate potential hotspots of future viral sharing, using a phylogeographical model of the mammal–virus network, and projections of geographical range shifts for 3,139 mammal species under climate-change and land-use scenarios for the year 2070.”

3. E3 IPBES Workshop report on Biodiversity and Pandemics UNCCD Library (IPBES workshop report) · 2020

   “The majority (70%) of emerging diseases(e.g. Ebola, Zika, Nipah encephalitis), and almost all known pandemics (e.g. influenza, HIV/AIDS, COVID-19), are zoonoses – i.e. are caused by microbes of animal origin.”

4. E4 IPBES Workshop report on Biodiversity and Pandemics UNCCD Library (IPBES workshop report) · 2020

   “and are linked to pandemic risk, as well as land use change, biodiversity loss and climatechange.”

The IPBES 2020 workshop report says almost all known pandemics are zoonoses (E3). It links land-use change, biodiversity loss and climate change to pandemic risk (E4), which supports ecosystem destruction as a recognised driver of pandemics. A peer-reviewed Nature study describes a mechanistic link between climate change and zoonotic spillover, but says it applies only "in some cases" (E1) and rests on projections for 2070 (E2). That makes climate a factor that raises risk, not an established direct cause. Both links are recognised as drivers, but the claim states them as more direct and complete causes than the evidence supports, so it is mostly true.