Step 2: Project the disease burden

Climate Change and Health, Justice, Equity, Diversity and Inclusion PlaybookIdentifying climate impacts on health, today and in the future

The goal of Step 2 is to estimate the current and future burden of the identified health risks, especially for populations deemed to be especially vulnerable due to greater exposure, increased sensitivity, or limited ability to adapt. BRACE guidance states that this step can be completed using qualitative and/or quantitative methodology.

Based on available resources and capacity, practitioners will need to decide how much time and resources can be put toward this step before moving to Step 3. In some cases, an academic partner may be able to assist a public health jurisdiction with this step if the public agency lacks technical capacity. Other potential partners with technical expertise may include a NOAA Regionally Integrated Sciences and Assessments (RISA) program1 or a local NWS weather forecasting office.2  It could be the case that one disease pathway (such as heat-related illness) can be projected, but other disease burdens are not as easy or straightforward to project. Don’t let this impede progress: acknowledge any limitations and continue to move forward in the framework.


Anticipate the limitations of a quantitative data approach to a disease burden projection in a JEDI context

When progressing through BRACE with a JEDI focus, take caution in relying solely on quantitative data analysis. Many quantitative methods and official reporting systems (e.g., hospital records) underestimate disease burden for particular populations due to the lack of consideration for unique cultural practices or structural factors, such as limited access to health care. These methods often review a population in aggregate and fail to parse out the disparities in disease projections due to differences in multiple domains such as socioeconomic status, cultural practices, occupation, or immigration status, among others. Particularly with historical quantitative data, marginalized populations’ experiences are rarely represented fully and accurately. If culturally sensitive adjustments are made for each subgroup, an aggregate disease burden can be more accurately determined.

With this in mind, consider consulting one or more of these common quantitative data sources for baseline disease burden:


woman with microphoneTraditional quantitative data collection, like the U.S. Census, can omit certain populations or fail to capture the intricacies of cultural or socioeconomic circumstances that can contribute to disease burden. As with Step 1, a qualitative approach can offer rich data solutions for health departments with diverse populations and create a more inclusive, accurate projection. Community leaders can highlight unique experiences and offer insights on health threats that may not be obvious at a glance of the data as a whole. These insights can lead to further data collection and analysis to encompass the health threat more fully and effectively prepare for climate events in the future. Qualitative data collection provides the opportunity for community leaders to provide testimony and advance understanding of specific population’s unique health experiences.

Assess data availability and accuracy. Ask: what populations’ health risk may not be accurately assessed in historical data records? At what level is data collected, i.e. state, county, neighborhood, and whose experience may be left out? Use your vulnerability assessment of at-risk populations to identify groups that may benefit from extra attention through qualitative data collection. Consider the data collection approaches below.

  • Deconstruct large datasets. For example, the incidence of respiratory diseases, such as asthma, is higher in the Swinomish Indian Tribal Community than its neighboring communities. Because the jurisdiction’s health reports are prepared at a summary level, respiratory diseases are not documented at levels specific to the Swinomish. Population-specific datasets would help to focus attention and resources with the communities that need them most.3
  • Use literature reviews to fill in data gaps. Due to limited capacity, many health departments are not able to do significant active work to project disease burden. The Minnesota Department of Health bolsters its disease burden projection by using literature reviews.4
  • Use secondary sources to enhance your analysis. California Department of Public Health’s CalBRACE program supplements Step 2 analysis with secondary sources collated into a bibliography due to the size of the state and limited resources.5
  • Host focus groups or conduct key-informant interviews with community leaders. Community members are the experts of their own lived experience and can highlight population-specific risks that may not be captured in traditional data collection.
  • Additionally, quantitative data sources may miss rich insights that can be gathered by assessing recent climate related events, such as extreme weather, wildfires, prolonged drought, or even associated utility failures. Consult collecting and analyzing briefings or after-action reports that may have been developed in the midst or immediately after an emergency. These reports are likely to highlight how at-risk groups were impacted in a real-life scenario.

Photo by S.Campos, courtesy ITU via Flickr Creative Commons


Consider indirect and emerging health consequences of climate change for at-risk populations

Some health impacts of climate change are less obvious than others. Because climate change is a cross-disciplinary threat, its impacts are felt across a variety of health spheres. A few examples are provided below to help enhance you project disease burden to include a more comprehensive examination.

Heat and crime
Heat is associated with increases in crime, and the heat-crime association is more pronounced in low-income neighborhoods.

  • A study of 57 countries found that each degree Celsius increase in annual temperatures is associated with a nearly six percent average increase in homicides.7
  • Another study found he most disadvantaged neighborhoods in St. Louis, MO are predicted to experience over half of the climate change-related increase in violence.8
  • From 2010-2017, Los Angeles violent crime incidence increased by 5.7% on days with temperatures above 85 degrees Fahrenheit compared to cooler days.6 This was more pronounced in less affluent neighborhoods.9

Natural disasters and human trafficking
Climate-related disasters intensify existing vulnerabilities, and displacement disrupts social systems that prevent the exploitation of families in crisis. The UN Environment Programme estimates that human trafficking increases by 20-30% during disasters.10  Low-income communities are especially at risk because they are disproportionately affected by infrastructural damages and poor access to recovery resources following disasters.11  Even in the U.S., children who are separated from their caregivers are more vulnerable to human trafficking, while public safety authorities are overwhelmed by immediate life-saving measures. For example:

  • In 2006 after Hurricane Katrina, many women experiencing homelessness arrived in Houston with no money, leaving them vulnerable to human trafficking.12
  • Following Hurricane Katrina, an increase in the number of buyers led to an influx of girls trafficked from the northern U.S. to affected areas.12
  • In 2017 after Hurricane Harvey, online ads with human trafficking connotations increased.12

Harmful algal blooms and subsistence farming

overhead view of algal bloom
Harmful algal blooms usually increase during warmer summer months, resulting in marine biotoxins harmful to human health.13  American Indian and Alaska Native communities have applied thousands of years of traditional ecological knowledge to assess risks associated with foods affected by harmful algal blooms. Today, the culture and identity of these traditions are gravely impacted due to increased incidence of such toxins. Shellfish, which provide a source of sustenance, ceremony and commercial harvest for many coastal tribes, and harmful algal blooms are increasing health risks.13

Photo by Zachary Haslic, courtesy Aerial Associates Photography, Inc., via Flickr


Consider these resources from different areas that have implemented community adaptation programs to mitigate the impacts of climate change, with a specific focus on vulnerable populations. Inclusion of resources does not imply endorsement from CDC or APHA.

Centers for Disease Control and Prevention Projecting the Climate-Related Disease Burden: A Guide for Health Departments & Projecting Climate-Related Disease Burden: A Case Study on Methods for Projecting Respiratory Health Impacts
The guide presents a starting point for health departments interested in developing climate change health impact projections and lays out a general map of the process of establishing exposure-response relationships and developing scenario-based projections.

The Case Study on Methods for Projecting Respiratory Health Impacts uses case studies (completed and in development) from Climate Ready States and Cities Initiative grantees utilizing the Building Resilience Against Climate Effects (BRACE) framework. These guidance documents are examples of specific methodology health departments can utilize to project climate-related disease burden.
Maryland Department of Health and Mental Hygiene climate and health profile report
The report summarizes how BRACE has been utilized to predict how climate effects might impact Marylanders’ health.
Oregon Health Authority checklist to identify and assess climate-related health risks
A variety of steps are outlined that include several useful resources for identifying and assessing climate-related health risks.
CalBRACE Adaptation Toolkit: Project disease burden guidance
This collection of tools, reports, and guides helps local health departments and communities understand, and plan to address the health risks of climate change.



1. About the regional integrated sciences and assessments program. National Oceanic and Atmospheric Administration Climate Program Office. Retrieved from https://cpo.noaa.gov/Meet-the-Divisions/Climate-and-Societal-Interactions/RISA/About-RISA

2. NWS weather forecast offices. National Weather Service. National Oceanic and Atmospheric Administration. Retrieved from https://www.weather.gov/jetstream/wfos

3. Swinomish climate change initiative. Climate Adaptation Action Plan. Swinomish Indian Tribal Community Office of Planning and Community Development. 2010 October. Retrieved from https://www.cakex.org/sites/default/files/documents/SITC_CC_AdaptationActionPlan_complete_0.pdf

4. Health-based guidance development process. Minnesota Department of Health. 2020 February 27. Retrieved from https://www.health.state.mn.us/communities/environment/risk/guidance/devprocess.html#developing

5. California Building Resilience Against Climate Effects (CalBRACE). Centers for Disease Control and Prevention. 2019 September 19. Retrieved from https://www.cdc.gov/climateandhealth/state-programs/ca.htm

6. Heilmann K & Kahn M. The urban crime and heat gradient in high and low poverty areas. National Bureau of Economic Research. 2019 June. Retrieved from https://www.nber.org/system/files/working_papers/w25961/w25961.pdf

7. Mares DM, Moffett KW. Climate change and interpersonal violence: a “global” estimate and regional inequities. Climatic Change 135, 297–310 (2016). https://doi.org/10.1007/s10584-015-1566-0

8. Mares D. Climate change and levels of violence in socially disadvantaged neighborhood groups. J Urban Health 90, 768–783 (2013). https://doi.org/10.1007/s11524-013-9791-1

9. Butchireddygari L. Heat waves precipitate more crime in poor areas, study in L.A. finds. The Wall Street Journal. 2019 June 24. Retrieved from https://www.wsj.com/articles/los-angeles-heat-wave-could-lead-to-crime-wave-in-poor-neighborhoods-study-says-11561392032

10. Witong L. The effects of climate change on migration and human trafficking. Soroptimist International. 2019 June 7. Retrieved from https://www.soroptimistinternational.org/the-effects-of-climate-change-on-migration-and-human-trafficking/

11. Natural disasters and human trafficking. Engage Together. Retrieved from https://engagetogether.com/2018/06/05/natural-disasters-and-human-trafficking/

12. Garsd J. Human trafficking is a hidden aftermath of natural disasters. The World. 2017 October 5. Retrieved from https://www.pri.org/stories/2017-10-05/human-trafficking-hidden-aftermath-natural-disasters

13. Impacts on Shellfish - Climate Change. Washington State Department of Health. 2019. Retrieved from https://www.doh.wa.gov/CommunityandEnvironment/ClimateandHealth/Shellfish