Science and Development Network
News, views and information about science, technology and the developing world
.jpg){kind=small}
.jpg){kind=spacer}
.jpg){kind=small}
Definitions
- Antibiotic resistance
- Bird flu
- Climate change & insect-borne disease
- Genomics
- Malaria
- Nanotechnology for health
- Tuberculosis
Below is a directory of terms used in the debate about climate change and insect-borne disease. Most of the terms have been reproduced from the WHO, US Environment Protection Agency, the UN University Institute of Advanced Studies, the Center for International Forestry Research, and the Meridian Institute.
A
Adaptation
Adjustment of natural or human systems in response to actual or expected climate change, or its effects, that lessens damage or exploits beneficial opportunities.
B
Biodiversity
The number of living organisms, and the variability among them and their environments.
Biological Diversity
Biological Diversity — more commonly known as biodiversity — is a collective term used to describe the totality and variety of living organisms on Earth. Biodiversity is usually classified at three levels — genes, species and ecosystems.
C
Carbon Dioxide (CO2)
The greenhouse gas whose concentration is being most affected directly by human activities. Carbon dioxide also serves as the reference to compare all other greenhouse gases (see carbon dioxide equivalents). The major source of carbon dioxide emissions is fossil fuel combustion. Carbon dioxide emissions are also a product of forest clearing, biomass burning, and non-energy production processes such as cement production. Atmospheric concentrations of carbon dioxide have been increasing at a rate of about 0.5 per cent per year, and are now about 30 per cent above pre-industrial levels.
Climate
Usually defined as the 'average weather'. More rigorously it is the statistical description of the mean and variability of factors such as temperature, precipitation and wind over a period of time ranging from months to thousands or millions of years.
Climate Change
(Also referred to as 'global climate change'). This term is sometimes used to refer to all forms of climatic inconsistency, But as the Earth's climate is never static, the term is more properly used to imply a significant change from one climatic condition to another. In some cases, ‘climate change' has been used synonymously with the term, 'global warming'. Scientists, however, tend to use the term in the wider sense to also include natural changes in climate.
Climate variability
Variations in the mean and other statistics (standard deviation and outliers for example) of the climate on all temporal and spatial scales beyond individual weather events. Variability may be due to natural internal processes within the climate system or to variations in natural or anthropogenic external forces.
D
Deforestation
The practices or processes that result in the change of forested lands to non-forest uses. This is often cited as one of the major causes of the enhanced greenhouse effect, on the grounds that the burning or decomposition of the wood releases carbon dioxide, and that trees that once removed carbon dioxide from the atmosphere in the process of photosynthesis are no longer present and contributing to carbon storage.
Degradation
Changes within forests which negatively affect the structure or function of the forest stand or site, and thereby lower the capacity of the forest to supply products or services. In the context of a REDD mechanism, forest degradation results in the net loss of carbon from the ecosystem.
Disability Adjusted Life Year (DALY)
An indicator of life expectancy combining mortality and morbidity into a summary measure of population health. This accounts for the number of years lived in less than optimal health and the time lost due to premature death. It was developed for calculating global disease burden and is also used by the WHO and the World Bank for example, to compare the outcomes of different interventions.
Disease burden
The impact of a health problem measured in terms of economic cost, mortality, morbidity, or other indicators. It is often quantified using Disability Adjusted Life Years (DALYs).
Drug resistance
Resistance to anti-tuberculosis drugs that develops because of sub-optimal therapy — usually by not completing the course of treatment.
E
Early warning system
A disease surveillance and response system designed to detect, as early as possible, any change from the usual or normally-observed frequency or phenomenon.
El Niño/Southern Oscillation (ENSO)
El Niño, in its original sense, is a warm water current that periodically flows along the coast of Ecuador and Peru. This event is associated with a fluctuation of the intertropical surface pressure patterns and circulation in the Indian and Pacific Oceans, called the Southern Oscillation. This coupled atmosphere-ocean phenomenon is collectively known as the El Niño Southern Oscillation or ENSO. During an El Niño event, the prevailing trade winds weaken and the equatorial counter current strengthens. This causes warm surface waters in the Indonesian area to flow eastward to overlie the cold waters of the Peru current. This event greatly impacts wind, sea surface temperature, and precipitation patterns in the tropical Pacific. It has climatic effects throughout the Pacific region and in many other parts of the world. The opposite of an El Niño event is called La Niña.
Emissions
Emissions of greenhouse gases and aerosols associated with human activities. These include fossil fuel burning for energy, deforestation and land use changes that result in net increases in emissions.
Endemic
Describes a species that is native only to a limited area, for example, a bird endemic to a particular island or a plant endemic to a mountain range.
Epidemic
An outbreak of a disease that affects a large number of individuals within a population or region at the same time. Compare to pandemic.
Epidemiology
The study of epidemics and the diseases that cause them, especially the factors that influence the incidence, distribution and control of infectious diseases.
Extreme weather events
Severe weather, such as floods, hurricanes and tornadoes.
G
Global Warming
An increase in the near-surface temperature of the Earth. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases. Scientists generally agree that the Earth's surface has warmed by about 1 degree Fahrenheit in the past 140 years. The Intergovernmental Panel on Climate Change recently concluded that increased concentrations of greenhouse gases are causing an increase in the Earth's surface temperature and that increased concentrations of sulphate aerosols have led to relative cooling in some regions, generally over and downwind of heavily industrialised areas.
Greenhouse effect
The effect caused by greenhouse gases such as carbon dioxide and water vapour that allow incoming solar radiation to pass through the Earth's atmosphere. They also prevent most outgoing infra-red radiation from the surface and lower atmosphere from escaping into outer space. This process occurs naturally but is enhanced by human activities such as fossil fuel consumption that emits greenhouse gases and increases their concentrations in the atmosphere.
Greenhouse Gas
Any gas that absorbs infra-red radiation in the atmosphere. Greenhouse gases include water vapour, carbon dioxide, methane, nitrous oxide, halogenated fluorocarbons, ozone, perfluorinated carbons, and hydrofluorocarbons.
H
Health system
The often complex set of people, institutions, resources and policies that exist to serve the health needs of a population. Health systems fulfil three main functions: health care delivery, fair treatment for all, and meeting non-health expectations of the population.
Host
A multicellular organism (such as a tree, dog, or human) colonised by either commensal or pathogenic microorganisms.
I
Immunity
The state of not being susceptible to disease; being able to resist disease. An effective vaccine gives a person or animal immunity to a disease.
Intergovernmental Panel on Climate Change (IPCC)
The IPCC was established jointly by the United Nations Environment Programme and the World Meteorological Organization in 1988. Its purpose is to assess information in the scientific and technical literature related to all significant components of the issue of climate change. The IPCC draws upon hundreds of expert scientists as authors and thousands as expert reviewers. Leading experts on climate change and environmental, social, and economic sciences from some 60 nations have helped the IPCC to prepare periodic assessments of the scientific underpinnings for understanding global climate change and its consequences. With its capacity for reporting on climate change, its consequences, and the viability of adaptation and mitigation measures, the IPCC is also looked to as the official advisory body to the world's governments on the state of the science of the climate change issue. [Source: IPCC]
K
Kyoto Protocol
The international agreement, reached in 1997 in Kyoto, Japan, which extends the commitments of the UNFCCC originally made at the Earth Summit in 1992. In particular, it sets targets for future emissions of greenhouse gases by the developed countries.
M
Mitigation
An anthropogenic (i.e. derived from human activities) intervention to reduce the emissions or enhance the sinks of greenhouse gases.
Monitoring
Performance and analysis of routine measurements to detect changes in the environment or health status of populations. Not to be confused with surveillance, although surveillance techniques may be used in monitoring.
Morbidity
Rate of occurrence of disease or other health disorders within a population, taking account of age-specific morbidity rates.
Mortality
Rate of occurrence of death within a population within a specified time period.
O
Offset
A process by which carbon emissions released by activities such as deforestation are balanced, or offset, by conservation or mitigation activities elsewhere.
Outbreak
A sudden appearance of a disease in a specific geographic area. Smaller than an epidemic or a pandemic.
P
Particulate matter
Small particles of matter such as dust and soot that are suspended in the air. Particulate matter is emitted from sources such as motor vehicles, some industrial processes and forest fires.
Pathogen
An organism that causes disease in another organism.
R
Reservoir of resistance
A phrase used to describe commensal bacteria that are resistant to antimicrobials. These commensal bacteria will not cause disease in their hosts; however, the resistance may eventually be transferred to an organism that will cause an antimicrobial-resistant disease in another host.
Resistance
A pathogen is said to be resistant to a drug when the drug has no effect on it. Pathogens can evolve to become resistant to a drug through repeated exposure to it. In October 2005, researchers said they had found a strain of H5N1 that was resistant to oseltamivir (see Tamiflu-resistant bird flu found in Vietnam).
S
Surveillance
Continuous analysis, interpretation and feedback of systematically collected data. Data is used to detect trends in disease spread or occurrence based on practical and standardised methods of notification or registration. Sources of data may be related directly to disease or factors influencing disease.
T
Transmission
The passing of a disease from an infected individual or group to a previously uninfected individual or group. The bacteria and viruses that cause disease can be transmitted from one person to another in various ways, including direct or indirect contact, through the air, via contaminated food or water, or through insects or other animals — vectors — that carry the disease.
V
Vector
An organism (e.g., Anopheles mosquitoes) that transmits an infectious agent (e.g. malaria parasites) from one host to the other (e.g., humans).
Vector-borne disease
Diseases that are transmitted by the bite of vectors such as mosquitoes or ticks. The more common vector-borne diseases include dengue fever, malaria, Lyme disease, West Nile virus, Rift Valley fever, chikungunya and yellow fever.
Vector competence
The ability of a vector (e.g., Anopheles mosquitoes) to transmit a disease (e.g. malaria).
Vulnerability
The degree to which a system is susceptible to, and unable to cope with, adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the character, magnitude, and rate of climate change and variation to which a system is exposed, its sensitivity and its adaptive capacity.
