Professor J E Banatvala CBE


Church End, Henham,

Bishop's Stortford, Herts CM22 6AN

Tel. 01279 850386


07 July 2008


Ms Charlotte Littleboy

Scrutiny Unit

House of Commons

London SW1P 3JA




Dear Ms Littleboy,


Health Effects of Climate Change: Role of Aviation


The accumulated data from a number of scientific studies demonstrates unequivocally that the world's climate system is warming. There are reports, almost on a weekly basis, in the scientific literature as well as via the media, of the effects of climate change, much of which in recent times is man-made. Less is known, however, about the health effects on populations resulting from such changes which may affect humans directly, but also less directly but equally important, as a result of disease in livestock and agriculture.


It must be remembered, however, that single events may occasionally be falsely attributed to climate change. Increased frequency and severity are likely to be significant. To ensure that adverse health is indeed related to climate change, it is important to assess surveys attributing variations to longer term effects of climate change rather than just annual variability. Furthermore, climate change must be disentangled from other drivers which may result in ill health, e.g. migration, deforestation, conflict. There may also be a reporting bias. Thus there is a risk that scientific communications with climate change in the title is likely to get published; it's a new growth industry.



Industrialised Countries

The UK: The UK is relatively well protected from many of the adverse effects of climate change. However, raised ambient temperatures will increase the incidence of food poisoning, particularly from salmonella. Climate change is of importance in increasing the risk from flooding from impacts of rising sea levels and increase in stormy weather. The frequency of floods, for example in the West Country and Sussex (Lewes) may well be attributed to climate change and this problem may increase. Fortunately since sanitation in the UK is of a high standard and there is good public health infrastructure, flooding has not been associated with an increase in water-borne infections. However, damage to property, particularly housing and delay in effecting repair, has resulted in considerable hardship for families, including stress and psychological problems. The number of people at high risk from flooding could increase from 1.5 to 3.5 million by 2100. Increased urban development may increase this risk. Climate change may well have resulted in some increase in Lyme Disease, a disease caused by a spirochaete and transmitted by certain ticks, but such vector borne diseases as malaria and various forms of encephalitis are likely to be imported and widespread indigenous transmission is unlikely. Nevertheless, as a precaution, surveillance for infection by West Nile virus which caused major outbreaks of disease, including fatalities, in the USA, is being conducted by the HPA. .


Other industrialised countries: In parts of Europe there has been an increase in tick borne encephalitis (Baltic States and South Scandinavia) and there was recently an outbreak of a mosquito borne infection Chikungunya in Southern Italy. This infection normally occurs in parts of Africa and Asia and is similar in its symptoms to Dengue. France experienced about 15,000 excess deaths during the August 2003 heat wave, particularly among elderly people as well as those with chronic disease. Lack of mobility was a major risk factor and in Paris younger members of the family as well as doctors who would have given support were on annual vacation. It cannot determined with any certainty whether this as yet singular event was the result of climate change, although it may have been a contributing factor. The effects of severe floods following the New Orleans hurricane were widely publicised; there were many deaths from drowning and widespread destruction of property, both domestic and industrial. Hurricanes in the vicinity of the East Coast of the USA occur almost annually but the undue severity of the one in New Orleans was almost unprecedented. Low frequency but high impact climate changes will result in modification of conditions to prevent flooding, particularly in coastal regions, as well as construction of buildings, both domestic and industrial, to withstand the ravages induced by storms.




Developing Countries

It is in developing countries, particularly in the Tropics as well as in the Arctic regions that the effects of climate change are already having a major impact on health. In Sub-Saharan Africa, for example, vector transmitted infections are affected by temperature, humidity and precipitation and include malaria, Dengue and West Nile encephalitis. The burden of climate change and infectious disease is enhanced by a significant proportion of the population suffering also from HIV/AIDS, severe respiratory and gastrointestinal infections, as well as malnutrition. Alternating climate change induced by heavy rainfall, drought and high temperatures, not only affect the health of the population directly, but also result in many diseases, often vector borne, in animals. Examples include Rift Valley Fever causing disease among sheep and cattle, and Trypanosomiasis (sleeping sickness caused by a parasitic protozoan transmitted by tsetse flies). About 50% of the global food crop is from supplies of rice, maize, wheat and potatoes. These, as well as other crops are susceptible to flooding, drought and various climate change induced diseases resulting from microbial infections. Food shortages will destabilise economies and also result in migration of populations to avoid famine which, in turn, may result in territorial disputes. The world's fish supplies are also at risk; about 50% of the world's population live near coastal zones and many developing countries are dependent upon fish as a protein source. Increased stress on fisheries driven by climate change, particularly warming of the oceans associated with increased acidity, will have a significant repercussion on the diets in many developing countries. Thus, infection by fungal and bacterial diseases, algae biotoxins and paralytic shellfish poisoning are already increasing. Rising temperature in the sea water in the Bay of Bengal favours the growth of V cholera which has resulted in the frequency and severity of outbreaks of cholera in the coastal regions of Bangladesh. In the Arctic climate change is already having an impact on infectious diseases, particularly food borne infections. However, flooding resulting from the melting of the permafrost has increased water borne infections. Change in the rodent fox population is at risk of transmitting rabies to humans. In addition, the Northern Range of arthropod vectors (e.g. mosquitoes) may result in infections being transmitted from animal hosts to humans.




Aviation and Climate Change

Much is being done to reduce the emission of climate change gases industrially and domestically, less so for aviation. Indeed, civil aviation is one of the world's faster growing means of transport and unless steps are taken now to curtail demand, aviation will soon become the major factor driving climate change.


Although airport development, which in the UK now includes proposals to expand Heathrow and Stansted, may not have a major affect on the health of the population in the UK, such proposals, if fulfilled, will have an a cumulative effect globally. Certainly the population in their homes or those responsible in the work place are being advised to reduce CO2 emissions, but is this sufficient? Providing an example which can readily be assimilated by the general public, it has been estimated that to offset emissions of CO2 from the proposed extended use of the existing runway at Stansted Airport, it will be necessary to replace 350 million conventional light bulbs with low energy bulbs, or shut 1.4 million homes (more than exist in Hertfordshire, Essex and Suffolk) or take 2.3 million cars off the road. For the proposed second runway at Stansted, or the third at Heathrow, the comparison would be even more drastic.


The Royal Commission on Environmental Pollution, in its report on the Environmental Effects of Civil Aircraft in Flight (2002) recommended restricting airport development, emphasising that short-haul passenger flights made a disproportionate contribution to the global environmental impacts of air transport. Furthermore, it stressed that air travel will become one of the major sources of anthropogenic climate change by 2050. This report expressed the fear that the Government showed little sign of recognising this regarding further growth of aviation as inevitable.


EU Members adopted the 1999 WHO Charter recommendations, stating that the welfare of communities must be put first when creating transport policy, adverse effects falling disproportionately on vulnerable groups, e.g. children, the elderly, those with disabilities and those socially excluded. The WHO stressed the importance of conducting Environmental (EIA) and Health Impact Assessments (HIA) assuring that air quality and noise pressure levels were acceptable for environments including schools, hospitals and dwellings.


HIAs should be conducted for major industrial developments including, of course, airports and with EIAs consider local and global issues and mitigating ill effects. For London, as yet, HIAs, although not statutory, have been conducted for Stansted but not for Heathrow, or, less importantly, for Gatwick as further expansion is not currently envisaged. However, the responsibility for the HIAs for both the increased use of the existing runway at Stansted and for the proposed development of a second runway was delegated to BAA who appointed a company (ERM) on its behalf, BAA thereby acting as both enabler and regulator. Scarcely a transparent exercise.


The HIAs for the increased use of the existing runway and for the proposed development of the second runway at Stansted excluded climate change from their Terms of Reference. When questioned, the relevant Strategic Health Authority which has a duty of care not only for those residing in the vicinity of Stansted Airport, but also globally, expressed the view that climate change was a national not a local issue, a view which contrasted with that expressed by the then Secretary of State for DEFRA. The Chairman of the Royal Commission on Environmental Pollution expressed the view to me, when questioned about the HIA for the first runway, that he thought it was "bonkers" to exclude climate change (his word not mine). The Director of the London School of Hygiene and Tropical Medicine, Sir Andy Haines, whose department has done extensive peer reviewed and internationally recognised work on the health effects of climate change, stated that mitigating the effects of climate change should be both a local and national priority. In the recent HIA for the proposed second runway at Stansted, the exclusion of climate change was justified on the grounds that the health effects of climate change had already been reported extensively by the DH in 2007. This report relates only to the UK and, as stated above, the impacts of climate change are global.


The Royal Commission on Environmental Pollution's Report on the Urban Environment (2007) has recommended "that the UK Government and devolved administrations develop a statutory framework for including Health Impact Assessments in the planning process, accompanied by appropriate guidance". However, the Government, particularly the Department of Health, has a duty of care to the population; DIFID has a more global responsibility. The Department of Health should ensure that HIAs are conducted independently, perhaps using the expertise of University departments. This may go some way to ensuring that commercial interests do not override environmental and health considerations.



What steps should the UK adopt?

Apart from taking up the recommendations of the Royal Commission on Environmental Pollution, ensuring the HIAs are conducted independently, the following areas are of importance:


1. Industrialised countries like the UK should continue to promote and extend high quality research into the breeding of drought and infection resistant crops.


2. 75% of emerging and re-emerging human pathogens are also present in animals. Many human infections are zoonoses, i.e. transmissions infected from animals to humans. Encouragement must be given to the development of vaccines to protect animals and thereby humans.


3. Responsibility for human, animal and plant health has been segregated and encouragement should be given to co-ordination with appropriate funding and political direction.


4. The development of co-ordinated surveillance, including the use and development of rapid diagnostic techniques which can be used in the field. Molecular diagnostics now make this possible.


5. Expertise in infections occurring in developing, particularly tropical countries, present at

the end of the war or for a while during "Empire" days, has been lost but should be regained. Unfortunately there is relatively little training today in microbiology in the medical undergraduate curriculum. This should be rectified. Opportunities to train abroad should be encouraged, whether by university departments, or by the HPA. Current resources constrain developments outside the UK. Reciprocal arrangements for training for those in the UK and the developing countries should be encouraged.



Yours sincerely,





Professor J.E. Banatvala


Adviser to Stop Stansted Expansion on Health related matters



1. Royal Commission on Environmental Pollution. The environmental effects of civil aircraft in flight. November 2002.

2. World Health Organisation, June 1999, charter on transport, environment and Health. Copenhagen: WHO 1999

3. Royal Commission on Environmental Pollution; The Urban Environment. March 2007

4. Banatvala J. Unhealthy airports. The Lancet 2004;364:646-648