Emergent disease

The GOOSE defines (in 2006) the emergent diseases as new infections, caused by the evolution or the modification of an agent Pathogène or a existing parasite .

They will result for example in a change of hosts, vector, pathogenicity or stock.

Categories

A disease can be at the same time old, permanent and emergent for the variable ones of pathogenic in question. For example, the influenza is an old disease, but that which is induced by virus IA H5N1 HP is an emergent disease.

A disease perhaps endemic and old in a part of the world, but known as emerging when it appears in an area before unscathed. for example, because it appeared for the first time in Europe in the northern hemisphere of the hemisphere in August 2006, the GOOSE classified the Fièvre catarrhale sheep like emergent disease in this part of the world.

A disease quasi-disappeared, or which had with a return of a variable missing for a long time can be D-emergent (ex; Fièvre of the valley of the Rift), which can occur when our immune system is not able any more to react to it correctly or when it became disease Nosocomiale. Examples: Leishmaniose S, or Paludism which locally became antibiorésistant, which was formerly present in Europe, which could return there. Evolutions " are observed; recent and not expliquées" distribution of several vectors anophéliens.

These diseases relate to often at the same time the man and the animal, including the aquatic animals (with an increased risk with the development of the pisciculture and intercontinental transport of shellfish, fish or shells. In Europe, in the event of appearance of an emergent disease in a pisciculture, the Member State concerned must implement the necessary measures in order to avoid the propagation of this disease and to inform the Commission and the other Member States of the situation. (If necessary, the list of the diseases is modified consequently).

Examples

Among the emergent diseases considered to be alarming for their gravity in medical term and/or the importances of their potential social-economic impacts, one finds for example (alphabetical order):

Chikungunya
Ebola (virus)
Fever catarrhale of the sheep
Fever of the valley of the Rift (virus)
Influenza (virus)
Disease of the language blue, disease affecting in particular bovine and caprine, due to by 24 viruses, last of North Africa there are 6 or 7 years in Europe (in Sicily in 2000, then Italy, Corsica and Spain and South-France, with hearths with the Benelux countries and in Allemagne").
Disease of Newcastle (virus),
Disease of Lyme (parasite)
Plague of the small ruminants,
Swine-fever African (virus)
AIDS
West Nile Virus (virus)

Causes

The Promiscuity between people and with the pets and/or savages, promiscuity between pets and wild animals, the universalization of transport and the exchanges, the erosion of the Biodiversity (including the Predatory retreat of the S), but also the Climate changes are factors recognized like being able to support the propagation of the emergent disease-causing agents throughout the world.

The diseases émergeantes often appear in a context of instability ecological, landscape, environmental or social (war, displacements of refugees, impoverishment of populations, etc).

The introduction of exotic species carrying microbes (rat + Plague with the Middle Ages in Europe), important changes in vegetable cover and the land use seem to count among the first causes of proliferation of the infectious illness. The Deforestation, but also the fragmentation increasing of the forests, accompanied by an intensification of the Urbanization and agriculture and by a modification of the uses of water puts brutally contacts the pathogenic ones formerly isolated in forest, without the ground or the sediments, etc with human groups which do not have there had ever been exposed and which lives under conditions of promiscuity and/or displacement supporting the contagion. The disappearance of forest cover is factor of stress for certain microbes and organizations (cf mutagen radiation UV, dehydration of the air, fires, etc)

The disturbance of the hydrous role of the Forest S, or them drainage (by modifying the access points to water for fauna) also intervenes in the propagation the pathogenic ones. The retreat or the disappearance of the predatory carnivores returns the animals much more sensitive to parasitism and the diseases (the sick animals are not eaten more in first as they were it formerly).

This process is known for a long time in tropical forest (ex: AIDS, Ebola, etc), but it could also be important in moderate forest. For example, the echinococcosis is mainly carried by a Campagnol which pullulates on average mountain in the mediums opened not densément scrap-metals around the fragmented forests where its predatory is fewer (and while wanting to poison the field voles, one often also poisoned their predatory).
Quand one pursued the foxes, these animals territorial benefitted from the " vides" left by the eradication campaigns to circulate much further. while transporting the rage very quickly through Europe.
On recently showed that the Maladie of Lyme, transmitted by the Tique S, in the North-East of the United States enormously increased while benefitting from the parcelling out of the forest which supported the development of two species which carry and convey this parasite, while disadvantaging their predatory. The mouse with white legs ( Peromyscus leucopus ) and the Cerf of Virginia proliferate in the fragmented forest landscapes. One showed in North America that the more important the parcelling out is and the smaller the fragments are; the more present the mouse is and the more the rate of individuals carrying ticks increases, and the higher the rate of tick carrying the parasite is. These two species are adapted to the Lisière S and they have less the predatory ones in these landscapes. In the large solid masses of forest nonfragmented by roads (where they subisté), the ticks do not pullulate and are less carrying the disease of Lyme).

One of the challenges of research is a better multidisciplinarity between epidemiologists and ecologists and specialists in the Social sciences.

Take care

The medical good management of crisis implies a Veille in the éco-epidemiologic field and ecological and an optimal reactivity.

The GOOSE, WHO and UNO support a permanent day before, and a program " Glews" (Total early warning system) in particular helping the 10 countries of Africa and 10 countries of Asia the most reached by the influenza aviaire" (virus H5N1).

the European commission supports on its side a " project; Eden " ((Emerging Diseases in has changing European Environment) which associates 48 partners in 24 countries to study, describe and quantify the impacts of the disease-causing agents/vectors and their relationships to the modifications écopaysagères and sociocultural. Eden must rest on the Télédétection, the epidemiologic Modélisation, but also sciences of the ecology and Biodiversité) to describe, model and supervise the operation of the emergent diseases in Europe.

Avian flu
Pathocénose
Epidemiology
Écoépidémiologie

External bonds

Conference INVS 5/2/07 " Anticipation, detection and answer to the emergent infectious risks in France" (April 24th, 2007, Paris)
Emerging Diseases in has changing European (EDEN) eNvironment- Integrated Project off the European Commission