Leptospira

 

Order: Spirochaetales,

Family: Leptospiraceae,

Genus: Leptospira.

Leptospirosis is infection with the Spirochaete Leptospira. It is an acute zoonotic infection of worldwide significance. Leptospirosis is seen in both humans and animals.  The primary reservoir is rodents such as rats, mice, wild rodents and once infected, they shed the organisms for life. 

Livestock farming is the major occupational risk factor for human leptospirosis since cattle, dogs, swine etc., can also be reservoirs.

                                   

Infected animals excrete Leptospira both in active infection and asymptomatic stage. The Leptospira survive and remain viable for several weeks in stagnant water. It is common in temperate or tropical climates - rare in North America. Transmission to humans occurs through penetration of the organism into the blood stream via cuts, skin abrasions or mucus membranes.

                                                    

Leptospirosis is also known as hemorrhagic jaundice, infectious jaundice, mud fever, spirochetal jaundice, swamp fever, swineherd's disease, caver's flu, sewerman's flu, Canicola fever (canine leptospirosis-dogs) etc

First human leptospiral disease was described by Adolf Weil in 1886, as an "acute infectious disease with enlargement of spleen, jaundice and nephritis. Leptospira was first observed by Stimson in 1907 from a post mortem renal tissue slice. Stimson named it Leptospira interrogans owing to its shape resembling interrogation (question) mark.

                          

Human infection also known as Weil's disease, is caused mainly by Leptospira icterohaemorrhagiae, which was isolated in 1915 by Inada. 

Spirochetes are divided into two families, Spirochaetaceae and Leptospiraceae. 

• Spirochaetaceae –include Treponemes, Serpulina and Borrelia 
• Leptospiraceae include Leptospira.

Leptospira is further classified into several species and subspecies, called serogroups and serovars, based on the surface (lipopolysaccharide -LPS) antigens. 

Genus Leptospira is divided into two species 

• L. interrogans includes pathogenic strains 
• L. biflexa includes saprophyte strains -from the environment. 

These two species are divided into serovars  as defined by agglutination techniques. There are approximately 60 serovars for L. biflexa, more than 200 for L. interrogans.

L. interrogans has more than 22 serogroups common examples being L. icterohaemorrhagiae, L. Canicola, L. australis, L. hebdomadis, L. andamana, L. pyrogenes etc

 Morphology

·       Leptospires are corkscrew-shaped bacteria, delicate flexible helical cells, about 0.1 µm in diameter by 6–20 µm in length, which differ from other spirochaetes by the presence of end hooks. They have numerous coils with ends hooked like umbrella handles. Actively motile, with single polar flagellum.

·       Stains poorly with aniline dyes.

·       Observed using Giemsa stains, fluorescent antibody techniques or by silver impregnation methods.

·       Best observed using dark field microscopy or phase contrast for observation under living conditions and otherwise by, electron microscopy due to narrow size.

 Growth characters/Cultural characters

o   Leptospires are aerobes and microaerophiles with an optimum growth temperature of 25–30°C and pH 7.2-7.5.

o   They grow in  media enriched with vitamins B1 and B12, long-chain fatty acids, and ammonium salts. Long-chain fatty acids are utilized as the sole carbon source and are metabolized by β-oxidation.

o   Media enriched with rabbit serum or several liquid and semisolid media such as Korthof’s, Stuart’s and Fletcher’s media, etc. can be used. They grow in laboratory media within 12-16 hrs. and in inoculated animals within 4-8 hrs.

o   Growth of leptospires may be slow on primary isolation, and cultures have to be retained for about 13 weeks before being discarded. Agar may be added at low concentrations (0.1– 0.2%).

o   Semisynthetic media such as EMJH : Ellinghausen-McCullough-Johnson-Harris medium which contains fatty acids and bovine serum albumin is commonly used. In such semisolid media, growth is seen beneath the surface of the medium, which becomes more turbid with incubation time. This growth is known as Dinger’s ring or disk.

o   Leptospires can also be grown on chorioallantoic membrane (CAM) of chick embryos –growth observed in 4-5 days.

o   Bacterial contamination in cultures prevented by using antibiotics. Inoculation of the sample intraperitoneally in gunea pigs and culturing the heart blood collected after ten minutes is a good method to obtain contaminant free cultures. Leptospires invade blood stream more readily than other bacteria.

o   Leptospiral cultures are maintained by repeated subculture or by storage in semisolid agar containing hemoglobin. Long-term storage in liquid nitrogen also yields good results and is the preferred method of storage for maintaining virulence.

Leptospirosis

Leptospires enter the host via small abrasions, cuts of the skin, conjunctiva, mucous membrane and genital tract. The bacteria enter blood stream or remain in the kidney tubules and be shed in the urine for a period of a few weeks to several months and even longer. 

Once the number of Leptospires in the blood and tissues reaches a critical level, lesions and other symptoms appear, due to the action of  leptospiral toxin(s) or toxic cellular components .

Endotoxin activity due to Leptospiral LPS (leptospiral lipopolysaccharide) has been reported as seen in other Gram-negative bacteria. Hemolysins such as phospholipases act on erythrocytes and other cell membranes containing phospholipids, leading to cytolysis.

 Pathogenesis

•      In natural reservoir hosts – infection asymptomatic. 

•      If infection is transmitted to other animals, cause clinical disease

•    Human infection- Leptospires enter the body through cuts, abrasions on the skin or through intact mucosa of mouth, nose or conjunctiva, when water is contaminated by urine of carrier animals

•      Incubation period 2-26 days (10 days)

         Symptoms

•  Mild undifferentiated pyrexia (fever) to Severe or fatal illness with hepatorenal damage (Weil’s disease)

•   In severe cases, the onset is acute, with rigor (stiffness), vomiting, headache and irritation of the eyes- retro-orbital pain (around orbit of the eyes), conjunctival redness etc.

•     The fever is irregular and subsides in about 10 days

•      Jaundice by the second or third day in 10-20 percent cases

•      Purpuric hemorrhages (small spots of blood appear on skin) - on the skin and mucosa

•      Albuminuria is common

Leptospirosis is of two clinical types- icteric (with fever) and non-icteric

•     Meningitis is common and in some, abdominal symptoms predominate. Hepatorenal failure, hemorrhage of skin and mucous membrane, jaundice, and myocarditis also seen.

•      Clinical diagnosis is impossible in majority of cases –misdiagnosis common

•      High vigilance and laboratory assistance important not to miss out leptospirosis identification

Serious cases of human leptospirosis caused by the serotype L. icterohemorrhagiae. Aseptic meningitis common in L. canicola infection. Abdominal symptoms in L. grippotyphosa infection.

But, clinical syndromes are not serotype specific- Any type of illness may be produced by any serotype.

Epidemiology

•      Leptospirosis- most widespread of zoonoses

•      Present in all continents, except Antartica

•      Pathogenic leptospires survive for long periods in (the convoluted tubules of) the kidneys in natural hosts, multiply and are shed in urine

•      Animal carriers excrete upto 100 million leptospires per ml of urine

•      Infected urine contaminates mud/water that is neutral or slightly alkaline-leptospires survive for weeks

•      People come into contact with such water-leptospires enter the body through abraded skin or mucosa and initiate infection

•      Certain occupational groups-agricultural workers in rice/cane fields, miners, sewage cleaners exposed to infection-more common in them

•      Leptospires can be shed through milk of lactating animals-die rapidly in milk

•      Human infection through milk unknown

•      Not shed in saliva-animal bites not infectious;   Arthropods do not transmit the infection

•      Animals as carriers- rats-ubiquitous, carry the most pathogenic serotype icterohemorrhagiae

•      Field mice carry grippotyphosa, pigs carry pomona, dogs carry canicola serotypes

•      Generally nonpathogenic in the reservoir animal

•      Of veterinary importance since infection in cattle/pigs cause economic loss

•      Infection among animals- transmitted by contaminated water/fodder

•      Human beings are an aberrant/end host- no transmission to other humans

•      Was a rural disease of agricultural workers-  Now, an urban problem in developing countries- overcrowding, insanitation, increasing rat population and habit of walking barefoot

 

Laboratory diagnosis 

Leptospires are seen in the blood during the acute phase of the disease but can seldom be demonstrated after 8-10 days. They persist in the internal organs, and most abundantly in the kidneys, so may be demonstrated in the urine in the later stages of the disease.

v  Microscopic Demonstration in blood/urine

v  Isolation in culture

v  Inoculation in Guinea pigs

v  Serological tests

 

Examination of Blood

•      Helpful in early stages of the disease (before antibiotics are given)

•      Leptospires disappear from blood after the first week

1) Examination of blood under dark field microscope/by immunofluorescence; but of little practical value

 

2)Three or four drops of blood are inoculated into EMJK or similar medium- incubated at 37⁰C for two days and left at room temperature in the dark for two weeks

•      Samples from the cultures are examined every third day for the presence of Leptospires under dark ground illumination

•      Primary isolation may be delayed and may take many weeks to months

•      Chances of isolation are increased by culturing blood daily at the early stage of the disease

•      Leptospires may be isolated from CSF also

3)      The blood from the patient is inoculated intraperitoneally into young guinea pigs

With virulent serotypes- icterohemorrhagiae, the animals develop fever, die within 8-12 days with jaundice and hemorrhage into the lungs and serous cavities

With other serotypes- canicola or pomona, animal may not become ill-Leptospires should be demonstrated in the peritoneal fluid, by blood culture or by serology

From the third day after inoculation, the peritoneal fluid is examined daily under dark ground illumination

When Leptospires are detected the blood withdrawn by cardiac puncture is inoculated into culture media

 

 Urine Examination

• Leptospires appear in the urine in the second week of the disease and intermittently thereafter for 4-6 weeks
• Urine should be examined immediately - Leptospires readily undergo lysis in acid urine

1)      Centrifuged deposit of urine is examined under dark field microscope

2)      Direct culture of urine seldom successful due to contamination but isolation is possible by inoculation into guinea pigs

 

Serological tests

• Antibodies appear in serum towards the end of the first week of the disease, increase till the fourth week, then reduces.
• Antibodies/Agglutinins are demonstrable years after the infection
• Serological tests can be- broadly reactive genus specific screening tests and the serotype specific tests

v  Genus specific/ Broadly reactive tests -identify Leptospiral infection without identifying the exact serotype

•      The antigens for these tests are prepared from the nonpathogenic L. biflexa Patoc 1 strain

•     Sensitized erythrocyte lysis (SEL), complement fixation, agglutination and indirect immune florescence, ELISA

•      ELISA to detect IgM and IgG separately, to determine the stage of infection can be done

•      Simple and rapid dip stick assays for detecting Leptospira specific IgM antibody in human sera available

v  Serotype specific tests

•      Identify the infecting serotype by macroscopic and microscopic agglutination tests

•      Macroscopic agglutination tests done with inactive formalinized suspensions of Leptospiral serotypes with serial dilutions of the test serum

•   Microscopic agglutination tests (MAT) use live cultures of different serotypes and agglutination is observed under the low power dark field microscope- more specific- done in reference laboratories

 

Prophylaxis

•      Leptospirosis results from contact of skin or mucosa with contaminated water

Ø  Rodent control

Ø  Disinfection of water

Ø  Wearing of protective clothing

•      Vaccination of high risk groups such as agricultural workers encouraged.  Immunity is serotype specific

Ø  Vaccination of dogs, cattles, pigs

 

Therapy

•      Sensitive to penicillin and tetracyclines

•      Treatment should be started early in the course of the disease

•      Penicillin given as IV : 1-2 million units 6 hourly for 7 days, for serious cases

•       A mild Jarish Herxheimar reaction seen in some

•      Doxycycline 200 mg orally given once in a week effective for prophylaxis

 

Jarish Herxheimar reaction - common detoxification response of the body to the increased toxins released during a treatment for pathogens

•      the amount of toxins released into the circulation is more than what our body can safely handle quickly -      lot of stress on internal organs, especially the colon, liver and kidneys that are involved in filtering toxins in the body

Ultrastructure of bacteria- External structures-glycocalyx & capsule

                     BACTERIAL CELL STRUCTURE

Procaryotic cells are in general smaller, grow extremely rapidly and lack the complex vesicular transport systems in comparison to eucaryotic cells. A variety of structures are found in procaryotic cells. Not all structures are found in every genus. Also, gram- negative and gram-positive cells differ, particularly with respect to their cell walls. Despite these variations procaryotes are consistent in their fundamental structure and most important components.

Procaryotic cells are bounded by a chemically complex cell wall. Inside this wall, and separated from it by a periplasmic space is the plasma membrane. The genetic material is localized in a discrete region, the nucleoid and is not separated from the surrounding cytoplasm by membranes. Ribosomes and larger masses called inclusion bodies are scattered about in the cytoplasmic matrix. Both gram-positive and gram-negative cells can use flagella for locomotion. In addition, many cells are surrounded by a capsule or slime layer external to the cell wall.

Structure	Functions
Plasma membrane	Selectively permeable barrier, mechanical boundary of cell, nutrient and waste transport, location of many metabolic processes  (respiration, photosynthesis), detection of environmental cues for chemotaxis
Gas vacuole	Buoyancy for floating in aquatic environments
Ribosomes	Protein synthesis
Inclusion bodies	Storage of carbon, phosphate, and other substances
Nucleoid	Localization of genetic material (DNA)
Periplasmic space	Contains hydrolytic enzymes and binding proteins for nutrient processing and uptake
Cell wall	Gives bacteria shape and protection from lysis in dilute solutions
Capsules and slime layers	Resistance to phagocytosis, adherence to surfaces
Fimbriae and pili	Attachment to surfaces, bacterial mating
Flagella	Movement
Endospore	Survival under harsh environmental conditions

External cell structures

Glycocalyx

·         All polysaccharide containing substances found external to cell wall

·         Thickest capsule to thinnest slime layer

Capsules

·         Protective structure secreted by the organism; seen outside the cell wall

·      Capsules -clearly visible in the light microscope using negative stains or special capsule stains; also with the electron microscope

·         Well organized & not easily washed off

·  Chemical composition unique to the organism -  Usually composed of polysaccharides; may be constructed of other materials. eg., Bacillus anthracis - poly- D-glutamic acid capsule

·  Pathogens usually are capsulated; prevents phagocytosis by host phagocytic cells eg., Streptococcus pneumoniae -Without a capsule, more vulnerable to destruction & less likely to cause disease, whereas the capsulated variant is pathogenic

Slime Layers

·         A slime layer is a zone of diffuse, unorganized material that is removed easily.

·         Capsules and slime layers usually are composed of polysaccharides

S-Layers

·         Many gram-positive and gram-negative bacteria have a regularly structured layer called an S-layer on their surface- S layer has a pattern like floor tiles and is composed of protein or glycoprotein

·         S- layers  are very common among Archaea bacteria, where they may be the only wall structure outside the plasma membrane.

·    In gram-negative bacteria the S-layer adheres directly to the outer membrane whereas it is associated with the peptidoglycan surface in gram-positive bacteria.

In general, glycocalyx, capsules, slime layers, S-layers

• helps maintain the shape and envelope rigidity of at least some bacterial cells
• aids bacterial attachment to surfaces of solid objects in aquatic environments or to tissue surfaces in plant and animal hosts
• protect bacteria against desiccation, pH fluctuations, osmotic stress, enzymes, or the predacious bacterium Bdellovibrio
• protection against bacterial viruses and  detergents
• protect some pathogens against complement attack and phagocytosis, thus contributing to their virulence
  
  

Participatory Resource Appraisal (PRA)

 Participatory Resource Appraisal is a way of learning about natural resources from local community. A field-based methodology evolved in1990’s- involves local community participation in study on natural resources. Participatory Resource Appraisal (PA) enable local people to identify their own priorities and make their own decisions about the future. The organising agency facilitates, listens and learns. PRA uses visual and flexible tools to ensure that everyone can join in regardless of background. It can be carried out in a place familiar to local community. PRA can help utilise natural resources on a sustainable basis.

 

•        Participatory - People are involved

•        Resource – source of supply of something that is available for use

•        Appraisal-finding out of information about problems, needs etc-

 

PRA was developed in Africa and Asia and is now used across the globe. A multitude of acronyms are used to describe it: e.g. PLA (Participatory Learning and Action), and PRA (Participatory Rural Appraisal).

 

PRA is an assessment and learning process for participatory planning and action. The approach aims to incorporate the knowledge and opinions of rural people in the planning and management of development projects and programmes. Participatory Appraisal is an empowerment approach that seeks to build community knowledge and encourage action at grass root level.

PRA is used when you are willing to let the community take control, when you want to base your actions on local knowledge and when you want to reach out to very diverse members of a community. The long-term goal of this approach is to empower and enable people to analyse and tackle their problems themselves.

 

 

Principles of Participatory Resource Appraisal

 

1) Listening and learning - through participation

2) Offsetting biases – which generally arise with “rushed proposals”

3) Proper utilization of community time – in the best possible way

4) Seeking diversity – learning from diverse conditions and people

5) Crosschecking – to minimize errors in the results obtained

 

PRA uses a lot of visual methods making it especially useful for participants. Various techniques are used including community/participatory mapping, diagramming (resource mapping, Venn diagrams etc.), focus group discussions, interviews, ecosystem mapping, etc. Oral and visual communication using diagrams, pictures etc. are prioritized to overcome literacy divides.

 

Techniques used include:

•        Ø Surveying and sampling, e.g. transect walks (systematic walk along a defined path (transect) across the community/project area together with the local people to explore the water and sanitation conditions by observing, asking, listening, looking), wealth ranking (information on the relative wealth and well-being of households in a village -helps in determining the social and economic status of households in a village), social mapping.

•        Ø Interviewing, e.g. group discussions, semi-structured interviews

•        Ø Community mapping, e.g. Venn diagrams, matrix scoring, ecograms, timelines.

 

 

The critical aspects of PRA are

1) Proper attitude and behaviour- for approaching and establishing links with local communities

2) Process of participation- process of rapport building, process of learning, pace of participatory process, broadening and deepening participatory process

3) Methods for interactive participation-interview, walks, etc

4) Sharing-information obtained from local communities should be shared for further learning to occur

 

Participatory Rural Appraisal (PRA) is thus an assessment and learning approach that focusses on empowering local people to actively involve in analysing their living conditions, problems, and potentials and bring about changes required. Changes are to be achieved by collective action and the local communities are encouraged to assume responsibilities for implementing appropriate actions. PRA follows the principles of decentralization and empowerment and ensures accountability to stakeholders. PRA is an exercise which transfers the role of planning and decision-making, traditionally taken by government institutions and development agencies, to the target group or community itself.

 

• PRA can be expensive at first as it is very important that people running the process are properly trained in the approaches and its values. If local community members learn the approaches themselves and become more confident, the costs of hiring external help may be reduced.
• PRA should be an ongoing process to ensure you are getting the most out of it.

• PRA can be extremely inclusive, flexible, and empowering. The knowledge produced by local community researchers will be highly reliable, and can help to identify and tackle underlying issues.
• When local community members have been trained to facilitate a process, this capacity remains within the community for the future.
• PRA is a creative and flexible approach that can complement and draw in other techniques as and when needed throughout the process.

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PRA Techniques

 • Transect Walk

• Timeline

• Social Mapping

• Seasonal mapping

• Venn diagram

• Matrix ranking

• Pair wise ranking

• Well being ranking

 Transect Walk

• It is mostly used for the appraisal of natural resources in terms of status, problems and potential. It provides a cross-sectional representation of the different agro-ecological zones.

• This has also been used for the depiction of various social aspects, such as, the caste and ethnic determinants of a settlement.

 Types of transect Paths

• Walk from a high point across to a low point in the area

• Just a straight line walk from one extreme point of the area to the other.

• To get more detailed view of the area, an S-shaped transect walk is also undertaken

 Key steps

• Locate a group of local people having some knowledge of the area and who are willing to walk with you for the exercise. Explain the purpose of the study.

• Go along with the people at the prefixed time on the already decided transect path.

• Observe the surroundings. If necessary, stop at certain locations for detailed discussions on the points emerging. It also gives you a breather and time to note down details.

• After returning, draw a transect on a large sheet of paper. Let the local people take the lead in drawing the transect diagram. Use your notes and the notes of other members of the transect team while making the diagram

• It is not uncommon to have two transects done for the same area- one by local men and another by local women. What is very striking s the different perspectives the two transect produce.

• The path, as far as possible, should remain the same for different transect walks. It helps in making the date more comparable. If you want the coverage to be detailed, you can select more than one path and have the same and different team do the transect walk.

 

Timeline

• It captures the chronology of events as recalled by local people

• Time line provides an aggregate of the various landmark events as perceived by the local people.

• Helps to learn from the community what they consider to be important past events, the historical perspective on current issues and to generate discussions on changes with respect to issues you are interested in.

 Key steps

• Identify some elderly persons in the village, explain the purpose of the exercise.

• The key questions:

• When was the village established? What are the important events in the history of the village? What major changes took place? What are the reasons for these changes?

• Make a note of the key points in brief in cards in bold letters.

• Once you feel that the list is more or less complete, keep the cards in a chronological order- the earlier events on the top and the later events lower down.

•  Add years to the left side of the list of events.

• Triangulate with other elderly persons in the village to see the correctness of the information given in the time line. Secondary sources of information can also be used.

 

Venn Diagram

Venn diagram is useful to study and understand local people’s perceptions about local institutions, individuals, programmes etc. Particularly useful to study and analyse:

 • Various institutions and individuals and their influences on the local people

• Various groups and individuals in the locality and their influence.

• Relative importance and usefulness of services and programmes

 

Eg., 1) Ask the participants to list the various institutions , which are assigned in different sizes of the circles. Size of the circle is proportionate to perceived importance- i.e., big circle more important

2) Distance from the centre is proportionate to access, i.e., less distance means easier access

Well being ranking

• Used for ranking and grouping households and communities on the basis of income/livelihood, wealth and other perceivable well being criteria such as educational attainment, food security etc.

• It is based on the perception of the local people. It helps to understand the local people’s conceptions of wealth, well-being and their views on socio-economic disparities between households.

• Helpful to explore issues like: livelihood, vulnerability, constraints to development as people perceive them, and to design intervention strategies in line with people’s aspirations.

 • To study inter-household and inter-group socio-economic disparities and to understand how the local people view them.

• Well being ranking is generally done with key informants. The selection is made based on the basis of their knowledge about the different households.

 

Make a list of households. The names of the head of households are written on separate cards. A group of key informants with good knowledge of the village are then asked to rank the household. Let the participants do the ranking on their own. Ask the participants to sort out the household cards into representatives categories of well- being. Ensure that the participants discuss among themselves and arrive at the well-being categories.

 As the participants arrange the household cards, ask them why they have placed the cards in a particular order. This gives you the criteria participants are using to do the well being ranking.

Natural Resource Accounting (NRA)

 

Natural Resource Accounting is based on the concept - ‘measurement of a resource leads to its better management’. Natural resource accounting is the compilation of data relating to natural resources within an accounting framework. NRA is an accounting system that deals with stocks and stock changes of natural assets, including biota (cultivated or wild), subsoil assets (reserves), water and land with their aquatic and terrestrial ecosystems. Natural resources accounts may involve both physical units and monetary values. Natural resource accounts differ from other data as they are organized in terms of stocks and flows.

Natural resource accounting can be used to support environmental policy, along with environmental impact assessment, economic analyses and public investment/expenditure reviews.

The resources include both those which contribute to marketable forms of production as well as non-commercial or environmental resources such as air, water and biological life. Natural resource accounts are regarded as a means of creating linkages between the environment and the economy. The terms 'NRA', 'green accounting' and 'environmental accounting' are used interchangeably.

The aim of NRA is to provide information on the state of natural resources and the changes affecting them. It is an important link in the chain of sustainable development. The term 'sustainable development' means a form of development which is capable of meeting the needs of the present generation without jeopardizing the ability of future generations to meet their own needs. 

Natural Resource Accounting (NRA) is an attempt to develop accounting systems to help monitor the responsible utilisation of natural resources, which will in turn lead to sustainability. There are various types of natural resource accounts: stock accounts, flow accounts, a combination of these two, emission accounts, waste accounts and environmental expenditure accounts.

Environmental accounting or NRA aims to provide a framework for organizing information on the status, use, and value of natural resources and environmental assets as well as expenditures on environmental protection and resource management.  NRA is also used to account for the depletion of natural resources and the fall in the environmental quality.

An environmental account must be:

• Purposeful and important for the account-user who depends on the reported information;

• Able to measure change in a defined account subject through time;

• Organised to enable comparisons and crosschecks in an internally consistent manner; and

• Comparable with other relevant accounts so it can provide the basis for more detailed or aggregated analyses

 

Aims of natural resource accounting:

Natural resource accounting is a means of demonstrating linkages between the environment and the economy. The resultant information can form the basis for the computation of environmental performance indicators. 

In short, Natural resource accounting can be used for:

• the demonstration of accountability for the management and protection of natural resources

• identifying environmental problems such as resource depletion;

• analyzing government policy;

• undertaking resource management and decision-making;

• monitoring sustainable development;

• drawing up (macro-economic) indicators for environmental performance or prosperity;

• improving benchmarks for measuring a country's national product.

 

Organisations:

There are a number of organisations which are active in this field, such as the United Nations Environment Programme (UNEP) and the United Nations Statistical Division (UNSD, formerly known as UNSTAT). These organisations include the Organisation of Economic Cooperation and Development (OECD), the World Bank, the World Resource Institute (WRI), the Statistical Office of the European Communities (EUROSTAT) and the Worldwide Fund for Nature (WWF)

The need for NRA took its first step at the United Nations (UN) conference on Human Environment in 1970 (Stockholm Conference) when the relationship between economic development and environmental degradation was discussed for the first time. 

The Brundtland Commission, set up by the UN, articulated the idea of close association between the environment and economic activities in 1987, which was followed up by environmental accounting and the Earth Summit at Rio de Janeiro in 1992.

 UN General Assembly resolution titled, "Transforming our world; the 2030 agenda for sustainable development" (25^th of September, 2016) which got the approval of more than 190 countries, requires the preparation of Natural Resource Accounts.

India is a signatory to this resolution.

The UN, in 2012, adopted the System of Economic and Environmental Accounting (SEEA). It is the latest internationally accepted framework for NRA.

Significance of Natural Resource Accounting

NRA can be effectively utilised for:

            (i)Resource management; (ii) Policy planning; (iii) Identification and accounting the natural resources within the economy; (iv) Monitoring sustainable development goals; (v) Combating climate change: and (vi) Aid to Environment Impact Assessments

What are the Challenges Related to Accounting of Natural Resources?

§  There is lack of proper training and capacity building among personnel involved.

§  Limitations in preparing the asset accounts - mapping the periodicity of data.

§  Multiple agencies are involved in data collection for resources; it may give rise to the issues of data sharing/data conflict.

 

    NRA has deep inter-linkage to sustainable development; and 10 of the 17 goals (Sustainable Development Goals or commonly known as the SDGs, 2030) are directly or indirectly related to the management of natural resources and their accounting. The government of India is a signatory to the UN General Assembly resolution on the adoption of SDGs titled, “transforming our world; the 2030 agenda for sustainable development”. Thus, it becomes an obligation for GOI to develop fine standards of resource accounting.

Accounting for natural resources will definitely aid both economical and ethical perspectives of life on earth. For example, accounting for forest wealth has a number of useful policy benefits, including the provision of a framework for analyzing and presenting detailed and diverse data in a manner which supports economically informed policy choices.