Climate Change and Health in Mozambique: Impacts on Diarrheal Disease and Malaria
As in many African countries, the scientific knowledge describing the health risks of weather, climate variability, and climate change needs to be strengthened in Mozambique. The Mozambican National Communication to the United Nations Framework Convention on Climate Change and the National Adaptation Program of Action recognize that climate change will bring about health impacts but do not elaborate on their nature or distribution. Similarly, the National Institute of Disaster Management published a report in 2009 investigating the effects of climate change on disaster risk in the country. The report highlighted a growing risk with little detail on the specific risks throughout the country. Although current associations between weather variables and a range of adverse health outcomes are generally understood — mostly derived from studies conducted in other countries — improved knowledge of current and projected risks in the different regions of Mozambique is needed to formulate evidence-based policies and programs.
The principal objective of this work is to build a scientific knowledge base to support informed investments and decision making in the health sector in Mozambique. The findings will help to shape the Ministry of Health’s (MoH) preparedness and response to emerging climate risks by working in concert with Mozambique’s new National Climate and Health Observatory, which combines weather and climate data to predict disease outbreaks, raise awareness of weather and climate impacts on health, and encourage government and public discourse on climate-sensitive health issues.
Key points from the report are provided below. See the full text (download from right-hand column) for much more detail.
Methods and Tools
This study examined the relationship between climate and climate-sensitive disease outbreaks using existing weather, climate, and health data. This study relied heavily on Mozambique’s Ministry of Health’s weekly Boletins Epidemiológicos Semanais (BES), which tracks incidence information on priority diseases such as malaria, measles, meningitis, diarrhea, dysentery, cholera, poliomyelitis, rabies, plague, and neonatal tetanus. Collation of health information begins at the service/facility level and information is aggregated to the district level on a weekly basis, offering the opportunity to analyze disease incidence at a weekly scale.
A preliminary evaluation of the relative coverage and completeness of data on the climate-sensitive diseases tracked by the Boletins Epidemiológicos Semanais found that data on diarrheal disease and malaria offered sufficiently consistent national coverage and reporting rates to support the analysis. Furthermore, these are two of the most prevalent and devastating diseases in Mozambique, making it key to understand how weather, climate variability, and climate change impact their occurrence.
Future Climate in Mozambique
- Mean temperatures will continue to rise by approximately 1ºC in the next 20 years and between 3ºC and 5ºC by the end of the 21st century.
- An increase in the number of days with temperatures exceeding 35ºC and a decrease in the number of nights with temperatures below 25ºC will occur.
- The difference between the daily maximum and minimum temperatures, called the diurnal temperature range, will also increase.
- Rainfall:Rainfall will continue to vary. While no statistically significant rainfall changes are projected, the current delayed start and earlier end to the rainy season in the northern region will likely continue and the intensity of single rainfall events is likely to increase.
Diarrheal disease under a changing climate
Future risk from diarrheal disease was evaluated for the period 2046–2065. Annual minimum temperatures are projected to increase across the northern, central, coastal, and southern regions on average 2.39ºC, 1.94ºC, 2.17ºC, and 2.09ºC, respectively, contributing to a projected increase in the burden of disease in the future, as shown in the table below (from page 7 of the report):
Malaria under a changing climate
The relationship between malaria transmission and climate is complex: climate can impact the transmission of malaria by affecting the parasite’s and the mosquito’s lifecycle, the human host, or any combination of the three. Predicting how changes in precipitation or temperature might affect transmission geographically requires detailed knowledge about all other factors involved in transmission. However, as a result of the expected changes in climate over the next several decades, the malaria profile in Mozambique is expected to change:
- As temperatures continue to rise, and given the strong statistical link between the increased number of days above 25ºC, malaria incidence is expected to increase in previously unsuitable regions, such as those in the higher elevation regions of northern Tete and western Niassa Provinces near the border with Malawi. Malaria risks are likely to remain consistent across the rest of the country.
- Since no strongly significant rainfall changes are projected for the next 20 years, precipitation variability, especially the oscillation between dry and wet periods that currently characterize rainfall patterns, will continue to contribute to malaria incidence through this time period, translating into continued malaria risks.
- The increased variability in precipitation, as well as the complicated relationship between malaria and temperature, means that malaria transmission will likely be more variable and unpredictable in the future.
Reducing health risks will require modifying current policies and programs and implementing new ones to explicitly consider climate variability and climate change. Adaptation actions should focus on building more resilient health systems, reducing overall vulnerability, and developing specific system capacities by investing in several entry points, including:
- Support research. Mozambique will be better prepared to aid its citizens through improved understanding of past trends and future projections in climate and their relationship to health outcomes.
- Improve epidemic detection and response. Exploring technological options for improving health data collection, such as SMS-based forms sent directly by health service workers, could facilitate the timely flow of information and responses.
- Deploy early warning systems. Having advance (early) warning that temperatures are expected to be higher or that a week is expected to be wetter than normal — and therefore that an increase in incidence rates is likely — would provide valuable time to put interventions in place.
- Build awareness. Communicate the risks posed by climate variability and climate change, as well as options for disease control, prevention, and treatment to the public and policy makers.
Leadership and governance foundations
- Enhance cross-sectoral governance and collaboration. Negotiate sharing agreements that could contribute to improved epidemic detection systems and ultimately support the development of early warning systems.
- Develop capacity within the health system.While health service workers may recognize the links between climate extremes such as droughts and floods and health sector impacts, they often have limited access to relevant climate information to modify their treatment and diagnosis plans in response to these changes. Important areas of investment in capacity development include:
- Training professional staff on the health risks posed by weather, climate variability, and climate change
- Training professional staff to differentially diagnose diseases based on early warning signs of health risks (using climate information)
- Building capacity to incorporate climate information into decision making. Beyond the development of the country’s health information system, the ability to use data for decision making is extremely weak. The health information system and its subsystems do not produce comprehensive, timely, or quality data for policy makers. During decision making, reforms and improvements should consider the use of weather and climate information and decentralization of health service delivery.
- Advance integrated risk monitoring. Well-functioning surveillance systems are crucial for effective disease control programs.
- Promote climate-smart health programming. Ensure that the information available on climate and disease impacts is used in the planning of resources and supply chain management.
- Strengthen public health services and facilities. Most operate off-grid and require alternate fuel supplies to support lighting, refrigeration, and sterilization, including the collection of medical commodities from district depots if supplies are unreliable. Furthermore, many of these facilities are located long distances from district storage facilities and are only accessible via unpaved roads that are challenging to drive on, especially during the rainy season.
- Support emergency preparedness and management. Establishing contingency plans to deploy surge support, both in staff and supplies, to areas where disease risks may rise in light of forecasts, could make supply chains more resilient to shocks.
Citation: CLIMATE CHANGE AND HEALTH IN MOZAMBIQUE: IMPACTS ON DIARRHEAL DISEASE AND MALARIA. Technical Report. March 2018. Prepared for: United States Agency for International Development by Chemonics International for the Adaptation, Thought Leadership and Assessments (ATLAS) project.