Surveillance Systems as the First Line of Defense Against Future Infectious Disease Outbreaks

By Edil A. Sepúlveda Carlo, Climate and Society ’13

The vulnerability and risks of climate change and variability for different regions of the world has been widely assessed and documented. Moreover, adaptation strategies and measures to cope with the expected impacts have been designed and developed. However, the timely and effective implementation of these adaptation measures had raised many concerns as the impacts of climate change are quickly emerging.

The United States Agency for International Development (USAID) is developing a project to identify adaptation measures that can be implemented in a fast-track approach in sectors such as agriculture, health and energy. I have been focusing my work, alongside colleague Margot Le Guen, on identifying fast track adaptation options, which are low cost, low tech and of simple design for the health sector in particular. My focus has been on malaria and cholera, which according to the Intergovernmental Panel on Climate Change would have the greatest burden on developing countries in the near and long-term future.

Adaptation options which are straightforward, easily implemented and scaled up have been executed by organizations such ad The Global Fund, the World Health Organization (WHO) and USAID in the last couple of years. These interventions, which have become the basis of my recommendations for this Fast-Track Implementation (FTI) Project from USAID, include the distribution of long-lasting insecticide-treated mosquito nets, indoor residual spraying, rapid diagnostic tests and behavior change communication campaigns for malaria. For cholera, they include improved sanitation facilities, safe drinking water treatment, drainage and storm water management and oral rehydration salt treatment. However, it has become evident throughout my research that climate prediction lies as the major factor for achieving the prompt and effective implementation of these adaption measures.

Climate is the key player for developing successful Early Warning Systems (EWS) that can effectively predict with enough lead-time when and where malaria and cholera epidemics are likely to occur. The EWS can be combined with Early Detection Systems (EDS), which promptly identify outbreaks of these infectious diseases in their early stages, for an early and effective treatment. The EWS and EDS are the basis for an overarching surveillance system, which can be implemented on a national or regional level, to effectively warn and promptly identify outbreaks of infectious diseases.

Climate variables such as sea surface temperatures in the region that El Niño occurs as well as regional temperature and precipitation have been used to developed seasonal climate forecasts. These have been successfully correlated with outbreaks of malaria and cholera in many epidemic regions of the world. Researchers from the International Research Institute for Climate and Society (IRI) have conducted research into the relationship of these climate variables with the onset of malaria outbreaks. One such study conducted in Botswana concluded that seasonal climate forecasts using precipitation data were effective in predicting malaria outbreaks with five months of lead-time in this country and other neighboring epidemic-prone areas. Furthermore, another study conducted in Eritrea and Madagascar proved that temperature and precipitation data were effective in identifying malaria incidence in these epidemic prone regions.

In addition to the seasonal climate forecasts that can be incorporated into EWS, case surveillance systems have also proved successful in malaria epidemic regions. A case study conducted also in Madagascar depicted the effectiveness of an EDS, which used the low cost technology of mobile phone’s SMS messages to record and track the early onsets of a malaria outbreak, helping to promptly placed the necessary interventions to control the epidemic.

Seasonal climate forecasts incorporated into EWS and complemented by low-cost, low-technology EDS have to become the first line of defense for any intervention involving control and prevention of malaria and cholera outbreaks. Although there still is research to be done for recommending appropriate FTI adaption options, these findings prove once more the importance of getting climate scientists, public health officials and policymakers to work together to combat infectious diseases.