Why local health departments are key to fighting climate change

October 5, 2023

Johns Hopkins assistant professor Mary Fox on the critical role these agencies play—and why they should be integrated in preparedness plans

Key Takeaways:

In a year that saw the East Coast struggling with extreme temperatures and choking smoke from Canadian wildfires, there’s little doubt that climate change is having an impact on public health.

Yet local public health departments, which help to protect and understand the health of community residents, are both underfunded and underutilized, according to Mary Fox, a Johns Hopkins Bloomberg School of Public Health assistant professor.

Featured Expert

  • Mary Fox

    Assistant professor, Health Policy and Management and Environmental Health and Engineering

    Mary Fox develops cumulative risk assessments that consider how biological, chemical, environmental, and social factors together affect the public’s health. See full bio

She explains why this on-the-ground perspective is a critical part of an effective and successful climate and health response.

Q: What are some recent examples of how climate change is having an impact on human health?

Mary Fox: This past summer was really remarkable for heat. Deaths are one of the primary outcomes of high temperatures, as well as heat exhaustion and heat stroke.

The wildfire smoke drifting down from Canada exacerbated asthma, and I was seeing people struggling with other respiratory issues. Here in Maryland, we even had a locally transmitted case of malaria—normally a tropical disease—for the first time in 20 years. It’s an example of the kinds of trends we’re seeing that correspond to the changing climate. The environments where mosquitoes and ticks live are changing. And mosquitoes are a vector for many, many diseases.

Q: What role do public health departments play in preparing communities for climate change-driven events?

MF: They play a critical role. First, local agencies know the vulnerabilities of their local populations—what proportion of people have heart disease and asthma, for example. And knowing how healthy or not your population is, even to the level of particular neighborhoods, is really important so you can line up against potential climate hazards. You have to know your neighborhoods, which feeds into overall planning. If you have a neighborhood with elderly people with multiple chronic diseases and the area is an urban heat island, you’re going to want to put a cooling center there, or invest in some nature-based solutions, like planting trees.

Local public health agencies also routinely collect health data and can track, for instance, the status of people with vulnerable conditions over time. It can also be used to evaluate programs. Did that cooling center in the neighborhood lead to fewer heat-related illnesses? We can look at it from year to year.

Another area of research that health agencies can undertake is understanding heat-sensitive illnesses. For example, in Baltimore, the health department is involved in the city’s climate adaptation plan, and one of their research areas is around food safety. That’s important because extreme weather events might take the power out for some amount of time, which can impact the food supply.

Q: You’ve studied climate adaptation plans in major cities. What are they doing right, and what can we learn from their efforts?

MF: Our 2022 study looked at the climate plans of cities around the world and what their public health agencies are doing—and not doing. We found that health was a main goal in 90% of the city plans, but only 70% actually had the health department engaged in the work. Despite this, they’re doing OK, because they’re using an all-hands-on-deck strategy. They have urban planners, the environment department, electric utilities, and the transportation sector all contributing to the effort. But health data is a resource unique to health departments. If you don’t have your health department involved in your plan, you’re missing vital information and a critical partner.

One city that’s doing this well is Baltimore. Its health department is engaged, particularly around preparedness and coordination with social service agencies, emergency responders, the fire department, and so on. The health department is also integrated into the thinking about flooding due to sea level rise. Water safety and water quality, and knowing the water system and how it would need to be managed in different situations, are important for Baltimore.

Q: What can we be doing to better support local health departments?

MF: Health departments are underfunded and understaffed. I teach at a public health school, and one point of pride is that we’re training the future workforce. The pandemic really did a number on the public health workforce—it was overwhelming. We need to make sure that our health departments are staffed up at every level.

Also, it’s important that health departments learn from one another. It’s the “community of practice” idea. There are national associations that convene county and city health officials to access resources and collaborate.

Q: What’s another key role that public health departments play?

MF: Communication is so important. From a public health perspective, one of the challenges is that the role of the health agency is somewhat hidden. When we prevent  illnesses, injuries, and deaths, nobody sees this. When you’re doing prevention work, it’s always a struggle to make sure people know we’re making a difference. It gets back to the importance of evaluation and health data.

But it’s also about how we’re talking. Maybe you don’t want to worry people that asthma rates are ticking up. But you also want them to know that if they go out on a smoky day instead of going to a clean air center, it could trigger an attack. Do you scare people? Or do you tell them the truth? We’re now less worried about people panicking. We just want them to know.

We looked at five core activities: vulnerability mapping, heat, early warning systems, preparedness, and emergency response. It turns out early warning systems are really, really effective. It’s a form of education. Getting that type of information out is really important to influence people’s behavior. Another important piece was monitoring not only health data but health-related data—air pollution, food safety.

Local health departments are already heavily engaged in on-the-ground activities like food safety activity and restaurant inspections. But they need to think about these activities in terms of the climate hazards that we face in our communities. How are we going to build that in over the long term? Everybody needs to look at how they are going to respond to climate change, which will continue until we really turn the corner on our greenhouse gas emissions. We need more and better integration and a climate-first mindset.