International team including Johns Hopkins experts makes excess deaths projections in Gaza

If fighting continues at a similar pace through August, the conflict in Gaza could cause between 58,260 and 66,720 excess deaths from military action, disease, malnutrition, poor sanitation, a lack of medical care, and more, according to a report issued in February by an international team of experts including researchers from Johns Hopkins University. Excess deaths refer to the number exceeding what would be expected based on Gaza data from the recent past (baseline deaths). If the conflict escalates, the projected toll could reach between 74,290 and 85,750 excess deaths.

The recent report, "Crisis in Gaza: Scenario-Based Health Impact Projections," funded by the UK Humanitarian Innovation Hub and led by Francesco Checchi from the London School of Hygiene and Tropical Medicine and Paul Spiegel, director of the Johns Hopkins Center for Humanitarian Health, provides projections with the goal of informing critical decision-making and policy related to humanitarian efforts in the region.

Image caption: Tak Igusa

Image credit: Will Kirk / Johns Hopkins University

The Hub recently spoke with research team member Tak Igusa, a systems expert and a professor in the Department of Civil and Systems Engineering at JHU's Whiting School of Engineering and a member of the Center for Systems Science and Engineering. Igusa is leading the modeling for trauma-related fatalities and supervises projections for communicable diseases.

What did the team learn from its first report? Did your analysis reveal any unexpected insights?

In my previous modeling work on natural disasters, I examined the impacts of the reduction of essential services and supplies. These models include the emergency response that would typically be brought in to help communities recover. Our Gaza report analyzed what would happen if such assistance was unavailable due to the conflict. We projected multiple health impacts, including non-communicable and infectious diseases, malnutrition, and maternal and newborn mortality. One of our findings is that there is a steadily increasing possibility of cholera, famine, and other humanitarian disasters that may result in higher mortality than the trauma deaths from the conflict. 


How do you model excess mortality rates in Gaza? What data sources do you rely on and how do you address potential data gaps or biases?

Our academic team encompassed a wide range of disciplines including epidemiology, disaster response, nutrition, and maternal and neonatal health. We also used panels of experts to provide estimates for various risk factors, such as the rate of mortality for various types of trauma, and the reproductive number for cholera and other infectious diseases. We used experts who were familiar with or had worked in conflict zones.

I am glad you asked about bias. We discussed the importance of producing an unbiased report in nearly every team meeting. There are some specific steps we took to remove possible sources of bias. First, we carefully looked for possible sources of bias in our data, which came from the academic literature or publicly available sources from the current or past conflicts in the Gaza Strip or other similar settings in the Middle East. Second, we made our data and methods, including the computation code, easily accessible on GitHub to demonstrate transparency and to allow others to reproduce and check our results.


How does your model account for compounding risk factors? For example, how might damage to infrastructure exacerbate the risk of death from food insecurity and lack of access to health care? 


As a systems modeler, I have been working with the team on the interactions between risk factors. We needed more time to complete this complex analysis for our February report, and are currently working on the broad health impacts of sustained malnutrition.


What additional data points could be incorporated into future studies to provide an even more comprehensive understanding of the situation and shed light on where resources are needed most? 


You are correct in noting that complete data is essential for assessing the humanitarian situation. The example I am thinking about now is food. We modelers can compute the total nutritional needs of the Gaza population, and we can also calculate the number of calories entering the Gaza Strip through emergency relief efforts. We also know that it is not possible to distribute these calories evenly and that there is a severe deficit in various regions of Gaza. The additional data we need in this example is related to the flow—or lack thereof—of food to the regions of the Gaza Strip with the most severe cases of malnutrition.


What is the goal or intended impact of making these reports publicly available? While the data itself may be neutral, there was initially some concern that releasing it could elicit strong feelings from various parties. Has that been your experience? 


The U.K. Humanitarian Innovation Hub funded our project to assess the wide health impacts of the conflict in Gaza. Our February report assessed this impact by comparing mortalities due to continuing or escalating conflicts with mortalities in a ceasefire scenario. We presented our numerical findings, pointed out the need for a multi-faceted health response, and highlighted the lifesaving impact an immediate ceasefire would have.



We got quite positive and, in many cases, respectful responses. This may be partly because our report is a comprehensive examination of the impacts of the conflict in Gaza conducted by a team of academics.


Are your research findings currently being used to inform decision-making about resource allocation or other humanitarian efforts?

The principal investigators, professors Paul Spiegel at Johns Hopkins Bloomberg School of Public Health and Francesco Checchi at the London School of Hygiene and Tropical Medicine, have disseminated the report through their networks with policymakers and humanitarian organizations internationally, including in the U.S., U.K., Israel, and Palestine. Key findings in our report have been published in all major news outlets and cited in the U.K. Parliament and the U.S. Senate.



A debriefing session that was most memorable to me was with USAID's Bureau for Humanitarian Assistance. Members of their response team had been studying our report and discussed in detail the parts of our projections that were directly related to their emergency relief plans.


Can your modeling approach and lessons learned be applied to other conflict zones or scenarios—such as Ukraine—or in places experiencing climate-change-induced movement of people?

One motivation for working on this project is that the new modeling approaches we develop can be applied to other contexts in the future. I have done some work on climate-induced migration, and the Gaza project has given me new insights and approaches that I can use to advance this migration research further.


Are there any other important points or considerations you wish to highlight regarding the team, its results, and your role?

This work is an example of the interdisciplinary collaboration that defines the One University concept of Johns Hopkins. There really are no barriers between our schools—and this has enabled a Whiting School faculty member like me to engage in challenging and rewarding humanitarian research.