Somalia is battling concurrent outbreaks of cholera, measles, and diphtheria driven by severe drought and displacement

Abstract

Somalia is experiencing concurrent cholera, measles, and diphtheria outbreaks driven by climate change, conflict, displacement, malnutrition, inadequate water and sanitation, and fragile health systems. This letter argues that these overlapping epidemics should be recognized as a syndemic rather than independent outbreaks because they share common structural determinants that amplify transmission and mortality. We advocate for integrated surveillance, combined vaccination strategies, strengthened laboratory capacity, nutrition support, climate-informed early warning systems, resilient primary healthcare, and sustained financing to improve outbreak preparedness and response in Somalia and similar fragile settings.

Text box 1. Contributions to the literaturew
➢ Frames overlapping infectious disease outbreaks as a population health challenge shaped by shared social, environmental, and health-system conditions.
➢ Extends the syndemic perspective to climate-affected and displacement-affected populations experiencing multiple infectious disease threats.
➢ Highlights the value of connecting disease control with vaccination, nutrition, safe water, sanitation, and primary healthcare rather than relying on separate programmes.
➢ Offers a practical framework that may help policymakers in Somalia and other fragile settings prepare for increasingly complex health threats linked to climate change, conflict, and displacement.

Dear Editor,

Somalia faces simultaneous outbreaks of cholera, measles, and diphtheria amid one of the world’s most severe humanitarian crises. Reported cases of these communicable diseases collectively increased from approximately 22,600 to over 46,000 within three months in 2025 [1]. The available reporting underlying these figures presents the burden cumulatively across the concurrent outbreaks rather than consistently disaggregating comparable case counts for each disease over the same period. The World Health Organization has emphasized that conflict, climate shocks, displacement, malnutrition, and recurrent cholera, measles, and diphtheria outbreaks continue to drive Somalia’s protracted health emergency [1]. This convergence deserves urgent international attention because it reflects a pattern in which environmental hazards, conflict, weak water and sanitation conditions, overcrowded internally displaced persons settlements, undernutrition, and limited surveillance capacity interact to amplify multiple disease threats simultaneously. These outbreaks should be understood as a single interconnected public health emergency rather than independent epidemics.

Prolonged drought and climate change increase cholera transmission through water scarcity and poor sanitation, as drought-induced water scarcity and flood-related water, sanitation, and hygiene failures intensify fecal-oral transmission and complicate outbreak control [2]. Conflict acts as an important upstream structural driver by weakening public institutions and health services, disrupting access to care and immunization, and contributing to population displacement. Displacement in Somalia is therefore driven by both conflict and climate-related shocks, with displaced populations often concentrated in overcrowded settlements where access to water, sanitation, nutrition, vaccination, and healthcare is limited. In 2022, Somalia recorded over 130,000 cases of acute diarrheal diseases, including 15,600 suspected cholera cases, marking the highest number in five years [3]. Food insecurity and malnutrition weaken immunity and increase measles severity, with approximately 1.84 million children aged 6 to 59 months projected to suffer acute malnutrition [1]. Among internally displaced persons in Banadir, severe malnutrition, respiratory infections, and diarrheal diseases were the leading causes of death, with malnutrition and measles the primary causes among children under five [4]. Overcrowded internally displaced persons settlements facilitate diphtheria transmission, as an estimated 3.5 million people were displaced in 2025, most living in overcrowded settlements with limited access to basic services [1]. All three outbreaks share the same underlying structural drivers: conflict, climate shocks, displacement, malnutrition, and fragile health systems [2].

Somalia’s health system exhibits limited vaccination coverage, with routine immunization completeness at approximately 20% and measles-containing vaccine second-dose coverage at only 3.3% [2]. DTP-3 coverage reached 71% in 2022 but remains insufficient for herd protection, and 87% of diphtheria patients had no documented immunization. Laboratory capacity is severely limited, with only 25 stool samples tested during the 2023 Banadir cholera outbreak, rendering surveillance essentially presumptive [5]. Surveillance coverage is patchy, especially in rural districts and among over 2.6 million internally displaced persons, contributing to delayed detection and under-reporting [6]. Shortages of diphtheria antitoxin and constrained vaccine supplies further hamper outbreak control [7]. These weaknesses amplify all three epidemics simultaneously because the same gaps in surveillance, laboratory confirmation, vaccine delivery, and access to primary healthcare affect cholera, measles, and diphtheria response efforts in parallel [6].

A syndemic describes the synergistic interaction of multiple diseases within populations experiencing shared social and structural adversities [1]. The mechanism linking cholera, measles, and diphtheria is that shared structural vulnerabilities increase exposure, susceptibility, delayed detection, and barriers to prevention and treatment, allowing each outbreak to compound the overall burden on already fragile communities and health systems. Managing cholera, measles, and diphtheria separately is insufficient because each disease program addresses only its specific pathogen while the common drivers—conflict, drought, displacement, malnutrition, and weak health systems—remain unaddressed [1].

Currently, outbreak responses are largely organized through disease-specific programs and emergency activities, with separate surveillance priorities, vaccination campaigns, supply chains, technical coordination structures, and funding streams for individual diseases. While such vertical approaches can deliver rapid disease-specific interventions, they may operate in parallel and fail to adequately address the common conditions sustaining all three outbreaks. The current vertical response therefore contrasts sharply with an integrated approach: shared surveillance systems could detect all three diseases simultaneously, coordinated vaccination campaigns could combine oral cholera vaccine, measles-containing vaccine, and diphtheria-tetanus-pertussis antigens, and nutrition programs could reduce susceptibility to all three infections [1]. Water and sanitation interventions would simultaneously reduce cholera transmission and decrease vulnerability to measles and diphtheria by improving overall population health [5]. Primary healthcare strengthening would provide the delivery platform through which integrated surveillance, vaccination, nutrition, and water and sanitation services could reach displaced and rural populations [2]. Countries that have achieved durable cholera reductions combined vaccination with reliable water access, routine chlorination, and community-level hygiene programs strengthened by improved surveillance [6].

Practical recommendations for Somalia include establishing integrated surveillance systems that monitor cholera, measles, and diphtheria through a single platform, building on existing Integrated Disease Surveillance and Response and DHIS2 infrastructure [6]. Combined vaccination campaigns should integrate oral cholera vaccine, measles-containing vaccine, and diphtheria-tetanus-pertussis antigens with mobile teams reaching displaced populations [6]. Strengthened water and sanitation interventions should prioritize climate-resilient boreholes, flood-raised latrines, and pre-positioned chlorination supplies [2]. Nutrition support should be integrated into outbreak response, as malnutrition increases mortality from cholera, measles, and diphtheria [6]. Laboratory strengthening requires expanding stool sample collection and confirmation to at least 10% of suspected cholera cases in hotspot districts and deploying rapid diagnostic kits to peripheral facilities [5, 6]. Climate-informed early warning systems should link hydrometeorological forecasts to disease hotspot mapping for proactive outbreak response [5]. Stronger collaboration between humanitarian agencies and government should be formalized through a national outbreak coordination mechanism [5, 6]. Finally, sustained and protected domestic and international financing should support integrated outbreak preparedness and response, recognizing that fragmented and short-term disease-specific funding can reinforce the same siloed approaches that this syndemic framework seeks to overcome.

Somalia’s crisis is a warning for other fragile states facing climate shocks and displacement, as the convergence of drought, conflict, malnutrition, and weak health systems that fuels these overlapping epidemics is not unique to Somalia [8]. Unless the international community adopts integrated syndemic preparedness supported by sustained financing rather than disease-specific emergency responses, similar overlapping epidemics will become increasingly common across climate-vulnerable, conflict-affected regions [2]. The era of treating concurrent outbreaks as independent emergencies must end; integrated syndemic preparedness is not an option but a necessity for protecting the world’s most vulnerable populations from the compounding disease threats of a warming planet.

Authors’ contributions

AAO and MAA conceptualized and designed the study. IAKH and AAO conducted the literature review. AAA and MAA prepared the first draft of the manuscript. AAA critically revised the manuscript for important intellectual content. All authors reviewed and approved the final version of the manuscript.

Funding

The authors received no specific funding for this work.

Data availability

No datasets were generated or analysed during the current study.

Declarations

Ethics approval and consent to participate

This article did not involve human participants, human data, or animals; therefore, ethical approval was not required.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.