by Sarah Hughes-McLure and Jen DeBerardinis
Climate change increases the burden of malaria
Deemed “among the greatest health risks of the 21st century” by the World Health Organization (WHO), climate change will not only impact lives directly through higher temperatures and extreme weather but also indirectly through the increased transmission and spread of infectious diseases[1].
The WHO and World Meteorological Organisation (WMO) identified malaria as one of the most climate-sensitive diseases[2]. The world’s most deadly tropical mosquito-borne parasitic disease, malaria kills approximately 1m people and affects as many as 1b in 109 countries in Africa, Asia, and Latin America[3].
Climate change is an important determinant of long-term malaria trends and has the potential to increase the global burden of malaria. Higher temperatures, rainfall and humidity impact malaria incidence by changing mosquitoes’ natural habitats, their longevity, and the growth cycle of the parasite in the mosquito[4]. This is likely to change the prevalence of mosquitoes, increase transmission, lengthen the transmission season, and change the geographic distribution of malaria by exposing new areas and populations to the disease. The World Bank estimates climate change will threaten previously unexposed regions in Latin America, Sub-Saharan Africa and China and increase the probability of malaria transmission by 50% in these areas[5].
The WHO and WMO estimate a 2-3C temperature rise could increase the number of people vulnerable to malaria by up to 5%, representing several hundred million people[6]. The Intergovernmental Panel on Climate Change (IPCC) predict temperature increases of 3.7-4.8C without further mitigation[7]. This impact will be exacerbated if climate change impacts the El Nino cycle: associated with increased risks of malaria being transmitted and high potential for malaria epidemics[8].
Impact of climate change on WHO operations
The WHO’s operations are impacted by the increased malaria burden in three ways:
1) Increased spread of the disease in current malaria endemic areas
2) Re-emergence of malaria in areas which have previously controlled transmission or eliminated the disease
3) Emergence of malaria in previously unexposed regions
So far, the WHO has undertaken assessments of health vulnerability and adaptation in over 30 countries and implemented major projects on climate change adaptation in 18. In 2010, with the UNDP, the WHO launched the first global project on public health adaptation to climate change with pilots in seven countries to increase adaptive capacity of national health systems to respond to climate-sensitive health risks[9]. The WHO is operating under its regular bilateral relationship of technical support to Ministries of Health.
One of the pilot project’s objectives was to prevent epidemic highland malaria in Kenya[10]. Climate change is expected to increase transmission intensity and lengthen the transmission season in areas where malaria already occurs as well as spread to new areas at higher altitudes. In the highlands, the disease is not currently monitored or forecasted. To reduce the burden of highland malaria epidemics the project targeted: improve the use of weather forecasting, improve disease prediction capacity, improve epidemic preparedness and disease detection and improve outbreak response.
There are still important knowledge gaps in the mechanisms of linkage between climate change and malaria. The WHO has taken a lead role in research to better understand the influence of climate change on malaria transmission risks.
The WHO has founded or is a member of many malaria programmes, for example launching Roll Back Malaria, a partnership of over 500 partners which coordinates action globally. To effectively combat malaria, the WHO must integrate climate considerations and risks into programme activities. It will need to build alliances not only between malaria programmes and health ministries but also environmental partners including meteorological organisations.
Beyond malaria, the climate change threat has broadened the WHO’s operations as it helps implement the 2015 Paris climate change agreement health initiatives[11]. For example, the WHO initiated an annual conference to develop investment strategies and economic assessments for climate change and global health and facilitate disease monitoring across countries.
Operating model changes
The increased burden of malaria will require some important changes in the WHO’s operating model: more predictive activities and flexibility, more and different resources, and continued modular projects.
Once research has been conducted to build models that link climate change to malaria epidemics, the WHO and health ministries will need to set up new infrastructure to predict malaria epidemics. This will significantly increase activities of forecasting weather, predicting disease and preparing rather than only responding to outbreaks. With more activities focused on predictive capacity, there will be a need for increased integration of technology into workflow. The shift to prediction will also mean a shift in the skills required on the ground: for example, weather forecasting rather than crisis response.
As climate in malarial regions becomes more volatile, the magnitude of outbreaks will become more volatile with higher uncertainty. By improving predictive capacity, the WHO reduces uncertainty and will be able to be more flexible in its operations to better respond to epidemics.
As the incidence of malaria increases, the WHO will be working with partners (traditionally health ministries) that are increasingly stretched. Given partners’ resource constraints, the WHO may need more resources to have the real option to take on additional activities in monitoring or delivery. In addition, as malaria emerges in previously unexposed regions, the WHO will need more resources and need to set-up relationships with new health ministries. This will require a significant training effort as new populations without prior experience of malaria are affected.
The WHO’s current operating model is modular as projects are set up with only the critical elements for that region; for example, one project might improve epidemic preparedness while another might be crisis response. This way of working improves flexibility and allows for efficient use of resources; the modular model will become even more critical as the impact of climate change on malaria incidence differs significantly by region.
Potential for additional private sector partnerships
Beyond governments and international organizations, the WHO has opportunities to build private sector relationships, as climate change makes companies more vulnerable to the economic impacts of higher malaria burden.
One of many companies in Africa taking steps to address malaria, the Senegal Sugar Company has partnered with the National Malaria Control Program to implement initiatives aimed at curbing malaria transmission in Senegal[12]. As the irrigated sugar fields where many employees work are breeding grounds for mosquitos, the impetus for the partnership came from many workers becoming ill and requiring substantial time away from work. With a team of 14 medical professionals, the Senegal Sugar Company has developed malaria control interventions such as distributing mosquito nets to employees, widespread use of rapid malaria diagnostic tests among employees, and quick prescriptions of treatments when malaria is diagnosed. Over the 6-month period after the program was implemented, the Senegal Sugar Company saw malaria cases among employees fall from 20 a day to only 24 over the entire half year.
In Ghana, the AngloGold Ashanti mining company has pioneered a public-private partnership model to fund comprehensive spraying of districts with high rates of malaria infection[13]. As in the Senegal Sugar Company’s case, efforts were spurred by concerns over lost employee productivity at its gold mine in Obuasi. In partnership with Ghana’s Ministry of Health, AngloGold Ashanti helped fund comprehensive indoor spraying across a number of districts, as recommended by the WHO, including mines, homes and other buildings. While much of the funding was provided through grants, there is a possibility this type of effort could be funded more broadly by the private sector as there is a favourable business case for investing in spraying. Within 2 years, the program achieved a 74% reduction in malaria prevalence in the region.
The rise in the burden of malaria and the need for surveillance and intervention in previously unexposed areas creates incentives for the private sector to engage in initiatives to combat malaria, particularly in regions where international organizations have not previously worked. This creates opportunities for the WHO to work with these companies by providing technical support to implement the most appropriate prevention and response protocols across different regions.
[1] WHO website: WHO global programme on climate change and health, http://www.who.int/globalchange/mediacentre/news/global-programme/en/
[2] World Meteorological Organisation and World Health Organisation, 2009, Factsheet #2: Climate information for protecting human health
[3] UN Chronicle, 2010, Climate change and malaria – a complex relationship
[4] UN Chronicle, 2010, Climate change and malaria – a complex relationship
[5] International Bank for Reconstruction and Development and World Bank, 2012, Turn down the heat – why a 4 degree warmer world must be avoided
[6] World Meteorological Organisation and World Health Organisation, 2009, Factsheet #2: Climate information for protecting human health
[7] IPCC, 2014, Summary for policymakers, Climate change 2014: mitigation of climate change, Contribution of working group III to the fifth assessment report of the IPCC
[8] UN Chronicle, 2010, Climate change and malaria – a complex relationship
[9] WHO website: climate change adaptation to protect human health, http://www.who.int/globalchange/projects/adaptation/en/
[10] WHO website: climate change adaptation to protect human health, http://www.who.int/globalchange/projects/adaptation/en/index6.html
[11] http://www.who.int/globalchange/conferences/2nd-global-climate-conf-scope-and-purpose.pdf?ua=1
[12] Making Malaria History website: http://www.makingmalariahistory.org/educate-and-advocate/senegal-media-gallery/private-sector-company-takes-on-malaria-elimination-in-senegal/
[13] The Guardian: https://www.theguardian.com/global-development-professionals-network/2014/apr/25/ghana-anglogold-malaria-reduction