This journal article, written by three researchers in Trinidad and Tobago, looks at malaria in the Caribbean. It asks why there are still outbreaks — including a big one in Jamaica in 2006/2007 — when the disease was allegedly eliminated in the late 1950s. The authors review malaria and vector data from across the Caribbean, summarising the pattern of imported cases as well as indigenous ones.

They identify three essential conditions for malaria transmission: presence of the vector, imported organisms and susceptible human hosts — all of which the authors show still exist across the Caribbean.

The authors suggest specific actions for regional policymakers to combat malaria. These include enhancing vector control skills, strengthening surveillance with new technologies, upgrading malaria therapy, increasing prevention strategies such as bed nets and raising public awareness of malaria. They emphasise that the role of climate change must be considered too, saying that rising temperatures could lead to new malaria vectors entering and colonising Caribbean islands and transmitting malaria on a major scale. But the authors are also careful to point out that the link to climate change is uncertain and remains contested in scientific circles.

This report from the WHO assesses the potential for creating early warning systems for vector-borne disease. It reviews the current state of research for several diseases such as dengue fever, leishmaniasis, malaria and West Nile virus.

The report includes an algorithmic framework for developing early warning systems, outlining data requirements and the different components of the system. It also contains two useful tables: one on the sensitivity of different infectious diseases to climate; and one summarising the existing research, identifying in which region the disease is most common, data availability and proposed actions.

A key problem in developing early warning systems, as highlighted by this report, is that non-climatic risk factors such as population immunity and food security strongly affect the potential for a disease outbreak. Equally challenging is the poor disease surveillance in many developing countries — the authors call on these countries to strengthen these systems, to help in the fight against climate change.

The report concludes that it will be important for researchers not to design these systems in isolation — health policymakers should be included at all stages of the design.

The third IPCC assessment report, Climate Change 2001, includes this section on the links between climate change and health. It offers a detailed look at how variations in climate, such as temperature or rainfall, could affect vector-borne disease. In particular, it evaluates computer models that predict climate impact on dengue fever and malaria. The assessment also looks at specific diseases such as leishmaniasis or schistosomiasis, explaining how the disease is spread and how changes in the environment might alter that spread.

The authors take a holistic look at the various factors involved. For example, in assessing schistosomiasis, they also consider the irrigation systems that will likely be needed to cope with expected water shortages resulting from climate change. The schistosomiasis parasite uses water snails as an intermediate host, so irrigation systems will need to be designed in such a way that they do not cause snail populations to multiply.

An update to the research on climate and vector-borne disease is also included in the fourth IPCC assessment report[796kB] although not in as much detail.

This journal article describes the first climate-based model used to predict outbreaks of dengue fever. Researchers from the University of Miami and the University of Costa Rica used climate data and vegetation indices from Costa Rica to predict disease outbreaks with 83 per cent accuracy.

Globally, there are up to 100 million cases of dengue fever, and its more dangerous form, dengue haemorrhagic fever, every year. The spread of dengue fever is set to rise as the world's climate changes. The importance of this model is that it could be used as the basis for an early warning system to prevent the spread of the disease by warning populations that are at risk.

The indices used in the model include variables such as El Niño Southern Oscillations and sea surface temperature, which affect populations of the Aedes aegypti mosquito that spreads the infection.

This Nature paper reviews evidence that a changing climate poses significant health risks and that global warming over the past few years has already increased illness and death worldwide.

Infectious diseases are strongly affected by climatic variations because the vectors that carry the bacteria or viruses do not have thermoregulatory mechanisms, say the authors. One of the most important existing sources of climatic variability is El Niño. This weather system has been shown to influence malaria in South America, rift valley fever in east Africa, cholera in Bangladesh and dengue fever in Thailand. If, as some scientists have suggested, climate change alters El Niño, the consequences will be significant.

The authors say there are some promising early warning systems for infectious disease. In Botswana, for example, two-thirds of the inter-annual variability of malaria can be predicted from sea surface temperatures and monthly rainfall.

A population's immunity to disease can greatly affect outbreaks of vector-borne disease, and isolating the influence of climate variability has proven difficult. This research study sets out to evaluate the effect of climate by accounting for population immunity.

The authors collated data on cholera cases from a predominant strain in the rural area of Matlab, Bangladesh, from 1966–2002. They used a model to incorporate immunity from previous infections and also potential cross-immunity from previous infections by other strains. They found that both forms of immunity were long-lasting — over 10 years in some cases. Yet the variation in transmission did not always match variations in immunity; at several points, it coincided with severe weather change such as monsoon rains or river overflow.

The authors suggest that forecasting disease will require considering climate variability alongside population susceptibility.

This extensive report from the Institute of Medicine of the US National Academies takes on the considerable challenge of understanding how, and to what extent, climate change will affect infectious diseases.

The report provides detailed summaries of current knowledge on diseases such as cholera and rift valley fever. Several pages are devoted to reviewing the latest climate science to contextualise the effect on infectious disease; it also includes several maps on climate anomalies to show how they are linked to disease.

One section highlights methods to assess climate change impacts on infectious diseases. These include analyses of historical records; monitoring programs, especially those that track disease in wild animals; and comparisons of satellite-derived environmental measurements with epidemiological data.

The report concludes with an analysis of the challenges facing policymakers. In many cases, it says, the best public health measures against climate change are those that strengthen health systems in general, such as better training for professionals and better disease surveillance. Policymakers will need to move away from the traditional thinking of individual policies for individual diseases, towards a joined-up approach aimed at tackling "systemic, long-term" stresses that cause a range of effects.

Paul Reiter, a researcher on insects and infectious disease at the Institut Pasteur in France, is not convinced that climate change will cause a rise in malaria in tropical regions. In this opinionated review he sets out to dispel widely held "common misconceptions" about the effect of climate variability on future transmission.

To do so, he examines the history of malaria. He finds that in the past, contrary to expectations, climate has often not affected the transmission of the malaria parasite. Researchers claim that the Anopheles mosquito that carries the parasite cannot survive extreme temperatures, yet Reiter cites examples of the mosquito finding ways to adapt. In Sudan, for example, they can survive temperatures of over 55 degrees Celsius by hiding in buildings in daytime and only feeding after midnight.

Reiter's main disagreement with prediction models is that they only look at how one climate variable, temperature, is likely to interact with mosquito populations. Temperature, rainfall and humidity are interconnected and cannot be analysed separately, he says. The ecology of mosquitoes and humans is too complex to predict future malaria prevalence and incidence from temperature alone, he adds.

As global temperatures rise, vector-borne disease is set to increase in the developing world but patterns will vary across countries. This review looks at how the prevalence of vector-borne disease will change in Africa, Asia, Australia, Europe, North America and South America.

As the authors explain, urbanisation levels will determine which diseases are likely to hit hardest. For example, dengue fever is a largely urban disease and will affect South America, where over 70 per cent of the population live in cities, far more than it will Sub-Saharan Africa, where less than 30 per cent of people live in urban areas. Malaria, by contrast, will have a bigger impact in Africa.

As ecosystems change, so will the distribution of vector species. Some will find their habitats expanded. A positive note is that most vectors cannot survive above about 40 degrees Celsius, so regions in which warming tips the temperature over this level could well see a drop in vector-borne disease — this is starting to be seen in Senegal, for example.

But the precise extent to which climate variability affects vector-borne disease is yet unknown, say the authors, which hampers evidence-based policy change.

This report provides a policy framework for assessing the impacts of climate change on health, including vector-borne disease, by considering five challenges: informational, poverty and equity-related, technological, sociopolitical and institutional.

It begins with a detailed outline of climate science so far and the financial cost of adaptation. The informational challenges relate to better monitoring and surveillance to gather urgently needed data on disease and mortality in different regions, and early warning systems to predict extreme weather events and associated disease outbreaks. Technological challenges include the development of vaccines for diseases such as malaria and dengue fever.

How do policymakers tackle such challenges? A key move will be for government and non-government agencies, academia and civil society to collaborate internationally. Surveillance and primary health information systems in developing countries must be improved and local communities need to share adaptation strategies.

Adapting to climate change also means investing in food security, clean water supplies and reforestation. Policymakers also need to stimulate industry to develop low-cost methods for recycling wastewater and desalinating sea water. Mitigating and adapting to climate change, say the authors, has become inextricable from policies to eradicate poverty or closing the gap on social inequalities and health.

1990 saw the first major effort to estimate the main causes of illness and the biggest killer diseases in different countries. The data are important for public-health officials to allocate their resources wisely but also for feeding into estimates to plan for the future. Importantly, these need to be regularly updated to ensure that health programmes are still going in the right direction. This paper updates the 1990 study and offer predictions up to 2030.

The most forceful change in disease trends is in developing countries, with the proportion of people affected by non-communicable diseases set to increase. Proportionally, the number of people with infectious diseases is set to fall, though not when it comes to HIV/AIDS.

Because the authors also rely on predicting socio-economic development trends, they created best-case and worst-case scenarios for economic growth. In the pessimistic scenario, by 2030, the three leading causes of illness will be HIV/AIDS, depression, and ischaemic heart disease; in the optimistic scenario, road-traffic accidents will replace heart disease as the third leading cause.

This report looks at the future consequences of climate change in the greater Himalayan region. Experts predict that global climate change will lead to major shifts in the strength and timing of climate systems affecting the region, and expect this to intensify in mountain areas.

The authors focus on changes in glaciers, permafrost and avalanches, as well as the implications for water supplies, ecosystems and hazards such as glacier lake outbursts and how these threaten regional populations.

The authors emphasise that because the poor and marginalised are likely to suffer the earliest and most, identifying changes in the environment likely to affect them is of utmost importance.

The authors highlight the need to work on policies and strategies — in land use, water management, disaster management, energy consumption and human health — in order to improve the adaptive capacities of communities at risk. They argue that community-led adaptive strategies and capacities, as well as substantial efforts to reverse the human drivers of climate change, are needed.

This collection of nine research articles, published by the Indian Academy of Sciences, presents the latest findings of a network of studies conducted by leading scientific institutes and researchers in India. They examine the likely national impact of climate change on issues such as water availability, tropical cyclone frequency, changes in forest type and malaria transmission rates. The collection also includes an analysis of current and predicted trends for greenhouse gas emissions from India, as well as commentary on mitigation strategies for ensuring sustainable development.

The Roll Back Malaria partnership aims to halve deaths from malaria by 2010. In its first comprehensive report since its launch in 1998, the partnership reveals that malaria still kills more than a million people a year in poor countries. But despite a resurgence of the disease in many parts of the world, the report outlines the progress being made in scaling-up control and prevention measures. These include fighting the spread of parasite resistance to drugs such as chloroquine by introducing new drugs, promoting the use of insecticide-treated nets and intermittent preventive treatment of pregnant mothers, and using early warning, detection and response systems to cope with epidemics. The full report and summary are available online in French and English.

The Third Assessment Report of the Intergovernmental Panel on Climate Change, published in 2001, is the most comprehensive and authoritative source of information on climate change. Its conclusions confirm and strengthen those of the previous reports: human-induced climate change is a reality and most of the effects will be negative, but a range of mitigation opportunities is available to address the problem.

The Report finds that most of the earth’s warming over the past 50 years can be attributed to human activities, and that its effects are already being felt. Global temperature is expected to increase by 1.4 to 5.8ºC over the next century, a significant increase on the projections of the 1995 Second Assessment Report. This briefing paper summarises the findings of the Third Assessment Report and the debates underpinning them, and discusses the likely outcomes of the Report.