Environmental HealthAwareness

Presented by

Lemel Dorvilus

Topic: Malaria

Date: November 6th 2009

Agenda•Significance of Malaria•What is Vector?•Biological Vector•Infectious Disease•Transmission•Preventing transmission•Impact on DDT•Malaria Cycle•Malaria Caused Deaths•Conclusion• References

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Environmental Health focused on population rather

than individual.

The Role of Environmental Health Department

• Promote healthy lifestyle.

• Prevent the spread of diseases.

• Identify the health risk in the community.

• Informing the public of health issues.

• Maintaining a safe and healthful environment.

Historical Figures

• John Snow

Father of modern epidemiology.He is an English physician who has studied

about the cholera epidemic in London in 1840.

Historical Figures

• Charles Edward A. Winslow – THE GREAT PUBLIC HEALTH LEADER OF THE 20TH CENTURY.

Theoretician and leader of American public health in the first half of the twentieth century.

Winslow definition of public health is still considered valid today.

Historical Background

• Edward Jenner • Louis Pasteur• Jon Snow• Edwin Chadwick

Turnlock, B. J. (2006). The public health workforce. In Public Health: Career choices that make a difference (pp. 1-25). Sudbury, Massachusetts: Jones and Bartlett Publishers

Enotes. (2009). Medicine and disease-What are Louis Pasteur's

contributions to the study of disease? Retrieved May 12,2009,

from http://www.enotes.com/history-fact-finder/medicinedisease/whar-louis-pasteurs-contributions

Environmental Health Achievement

• In 1880, scientists discovered the real cause of malaria • Discovery of Vaccine• Discovery of Causes of Infectious diseases • People live longer • Birth delivery to healthier babies• Better drinking water• Motor vehicle safety• Utilization of tobacco as a health hazard• Infection Control, hand washing• Using gloves and mask as protective barriers• Centers for Disease Control and Prevention. (1999). Ten great public health achievements: United States, 1900-1999.

Retrieved May 11, 2009, from http://www.cdc.gov/mmr/preview/mmwrthml/0056796.htm

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Significance of Malaria?• Malaria is a life-threatening parasitic disease

transmitted by mosquitoes. It was once thought that the disease came from fetid marshes, hence the name mal aria, ((bad air).

• In 1880, scientists discovered the real cause of malaria a one-cell parasite called plasmodium. Later they discovered that the parasite is transmitted from person to person through the bite of a female Anopheles mosquito, which requires blood to nurture her eggs (Talaro, 2008).

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Significance of Malaria? Cont’d• Malaria is a vector-borne infectious disease

caused by protozoan parasites.• It is widespread in tropical and subtropical

regions, including parts of the Americas, Asia, and Africa.

• Each year, there are approximately 515 million cases of malaria, killing between one and three million people.

• the majority of whom are young children in Sub-Saharan Africa.

• Malaria is commonly associated with poverty, but is also a cause of poverty and a major hindrance to economic development (Talaro, 2008). .

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What is vector?

• There are two types of vector that convey infectious organisms to a host: mechanical and biological.

• In epidemiology, a vector is an organism that does not cause disease itself but which transmits infection by conveying pathogens from one host to another(Vector Control, 2009).

• Microbes do not multiply within mechanical vectors - mechanical vectors only physically transport microbes from host to host.

• In contrast, microbes must propagate within a biological vector before the biological vector can transmit the microbes (Talaro, 2008, pp. 404).

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What is vector? Cont”d

• A classic example is the anopheles mosquito which acts as a vector for the disease malaria by transmitting the malarial parasite plasmodium to humans. In this case plasmodium is harmless to the mosquito (its intermediate host) but causes the disease malaria in humans (its definitive host).

• In molecular biology and genetic engineering a vector is a vehicle for transduct genetic material into a cell.

• A viral vector is a virus which has been modified to transport specific genetic material into a cell, e.g. for gene therapy.

• A plasmid vector is made by splicing a DNA construct into a plasmid. Various techniques are then used to transfect the plasmid into the cell (Talaro, 2008).

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Biological vectors

• Biological vectors are often responsible for serious blood-borne diseases, such as malaria, viral encephalitis, Chagas disease, Lyme disease and African sleeping sickness(Vector Control,

2009).

• A common strategy, used to control vector borne infectious diseases, is to interrupt the life cycle of a pathogen, by killing the vector (Vector Control, 2009).

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Infectious Disease• The term infectivity describes the ability of an organism to enter, survive and

multiply in the host, while the infectiousness of a disease indicates the comparative ease with which the disease is transmitted to other hosts. An infection however, is not synonymous with an infectious disease, as an infection may not cause important clinical symptoms or impair host function.

• An infectious disease is a clinically evident disease resulting from the presence of pathogenic microbial agents, including pathogenic viruses. These pathogens are able to cause disease in animals and/or plants.

• Transmission of an infectious disease may occur through one or more of diverse pathways including physical contact with infected individuals. These infecting agents may also be transmitted through liquids, food, body fluids, contaminated objects, airborne inhalation, or through vector-borne spread .

• (Porta, 2008)

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Transmission

• An infectious disease is transmitted from some source. Transmission may occur through several different mechanisms such as sneezing, coughing, kissing, singing, aerosolized (respiratory disease and meningitis).

• Gastrointestinal disease: ingestion of contaminated food and water.

• Sexually transmitted disease: bodily fluid, as a result of sexual activity and so on (Talaro, 2008).

•

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Transmission cont’d

• An example of a mechanical vector is a housefly, which lands on cow dung, contaminating its appendages with bacteria from the feces, and then lands on food prior to consumption. The pathogen never enters the body of the fly.

• In contrast, biological vectors harbor pathogens within their bodies and deliver pathogens to new hosts in an active manner, usually a bite (Talaro, 2008).

•

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Preventing transmission

• One of the ways to prevent or slow down the transmission of infectious diseases is to recognize the different characteristics of various diseases.

• Another effective way to decrease the transmission rate of infectious diseases is to recognize the effects of small-world networks(Vector Control, 2009).

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Impact on DDT

• DDT was the first synthetic pesticide of the modern age. It promised much, but ultimately created widespread concern as an environmental hazard.

• DDT is moderately to slightly toxic to mammals. It mainly affects the central and peripheral nervous systems, and the liver.

• DDT is very fat-soluble and is therefore found in fatty foods such as meat and diary products.(What is DDT, 1998)

• My position is to control the level of toxicity by using a measurable control method.

• DDT is good a good product to use to eradicate malaria.

• Malaria is the enemy of human and ,therefore, it must be eliminated.

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Malaria Cycle• The malaria parasite enters the

human host when an infected Anopheles mosquito takes a blood meal. Inside the human host, the parasite undergoes a series of changes as part of its complex life-cycle. Its various stages allow plasmodia to evade the immune system, infect the liver and red blood cells, and finally develop into a form that is able to infect a mosquito again when it bites an infected person. Inside the mosquito, the parasite matures until it reaches the sexual stage where it can again infect a human host when the mosquito takes her next blood meal, 10 to 14 or more days later.

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Malaria Caused Deaths• The World Health Organization

collects information on global deaths by International Classification of Disease (ICD) code categories. The following table lists the top infectious disease killers which caused more than 100,000 deaths in 2002 (estimated). 1993 data is included for comparison (Vector Control, 2009).

Major Health Challenges

Assessment

Health Care Reform

Access to care

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Conclusion

• Malaria can be cured by antimalaria drugs. However, in certain region, the parasites have developed resistance to certain ant malarial drugs. Plasmodium Falciparum is the predominant parasite causing over 1 million deaths each year in the world (Vector Control, 2009).

• That is the reason why the experts suggested to have a constant environmental monitoring control. The monitoring control allows the healthcare professionals to estimate the exposures to people resulting from the toxic materials that are being released(Moeller, 2005,p.408).

Centers for Disease Control and Prevention. (1999). Ten great public health achievements: United States, 1900-1999. Retrieved May 11, 2009, from http://www.cdc.gov/mmr/preview/mmwrthml/0056796.htm

Epidemiology State of Florida. (2009). Retrieved May 11, 2009, from http://www.doh.state.fl.us/disease_ctrl/epi/swineflu/index.html

Enotes. (2009). Medicine and disease-What are Louis Pasteur's contributions to the study of disease? Retrieved May 12,2009, from http://www.enotes.com/history-fact-finder/medicinedisease/whar-louis-pasteurs-contributions

Mason, D. J., Leavitt, J. K., & Chaffee. M. W. (2007). Policy & politics in nursing and health care (5th. Ed.). St-Louis: Saunders.

Multilateral Initiative on Malaria.( 2009, November). Malaria Foundation International. Retrieved November 6, 2009, from http://www.malaria.org/

References

References

Moeller, D.W. (2005). Environmental Health, 3rd edition. Cambridge, MA: Harvard University Press.

OSHA, (2009). Safety and Health Topics: Benzene. Retrieved September 16, 2009, from http://www.osha.gov/SLTC/benzene/evaluation.html

Porta, M. (2008). A Dictionary of Epidemiology. New-York: Oxford University Press, Inc.

Schneider, M. (2006g) Epidemiology: The basic Science of Public Health. Introduction to Public Health (pp.51-55), Sudbury, Ma, Jones & Bartlett.

Schneider, M. (2006h) Powers and Responsibilities of Government. Introduction to Public Health (pp. 31-39), Sudbury, Ma, Jones & Bartlett.

Schneider, M. (2006i) Public Health: Science, Politics, and Prevention. Introduction to Public Health (pp.3-5), Sudbury, Ma, Jones & Bartlett.

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References

Talaro, K. P. (2008). Foundations Microbiology6th ed. New York: Mc-Graw-Hill.

Vector Control. (2009, August). Retrieved October 8, 2009, from World Health Organization : http://apps.who.int/malaria/vectorcontrol.html

Vector Control. (2009, August). Retrieved October 8, 2009, from World Health Organization : http://apps.who.int/malaria/vectorcontrol.html

What is DDT. (1998, , June). This article first appeared in Pesticides News No.40, , pp. 18-20. http://www.pan-uk.org/pestnews/Actives/ddt.htm

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