GLOBAL ERADICATION OF DISEASE Medical Geography INTRODUCTION Eradication
GLOBAL ERADICATION OF DISEASE Medical Geography
INTRODUCTION � Eradication is the reduction of an infectious disease's prevalence in the global host population to zero � Disease eradication is an absolute process in which an infectious disease is terminated completely from the whole world.
DIFFERENCE BETWEEN ELIMINATION AND ERADICATION � Disease eradication is sometimes confused with disease elimination which means: � “eradication of an infectious disease from a large geographical region or political jurisdiction � When a disease stops circulating in a region, it is considered as eliminated in that region � If a particular disease is eliminated worldwide, it is considered as eradicated. � Polio for example was eliminated from USA in 1979 after widespread efforts of vaccination programs
CONTINUED � Further confusion arises from the use of the term eradication to refer to the total removal of a pathogen from an individual (also know as clearance of an infection). particularly in the context of HIV and certain other viruses where such cures are sought.
ERADICATION CRITERIA � � Selection of infectious diseases for eradication is based on rigorous criteria, as both biological and technical features determine whether a pathogenic organism is (at least potentially) eradicable. The targeted organism must not have a non-human reservoir (or, in the case of animal diseases, the infection reservoir must be an easily identifiable species, as in the case of rinderpest), and/or amplify in the environment. This implies that sufficient information on the life cycle and transmission dynamics is available at the time an eradication initiative is programmed.
CONTINUED � � An efficient and practical intervention (such as a vaccine or antibiotic) must be available to interrupt transmission of the infective agent. Use of vaccination programs before the introduction of an eradication campaign can reduce the susceptible population. The disease to be eradicated should be clearly identifiable, and an accurate diagnostic tool should exist. Economic considerations, as well as societal and political support and commitment, are other crucial factors that determine eradication feasibility.
CONTINUED � � � � Two infectious diseases have successfully been eradicated: smallpox and rinderpest. There also four ongoing programs, targeting poliomyelitis, yaws, dracunculiasis, malaria. Five more infectious diseases have been identified as of April 2008 as potentially eradicable with current technology by the Carter Center International Task Force for Disease Eradication—measles, mumps, rubella, lymphatic filariasis and cysticercosis
ERADICATED DISEASES � Smallpox was the first disease, and so far the only infectious disease of humans, to be eradicated by deliberate intervention. � It became the first disease for which there was an effective vaccine in 1798 when Edward Jenner showed the protective effect of inoculation(vaccination) of humans with material from cowpox lesions
CONTINUED Detailed analysis of national records the global eradication of smallpox was certified by an international commission of smallpox clinicians and medical scientists on 9 December 1979, � It was endorsed by the General Assembly of the World Health Organization on 8 May 1980. � However, there is an ongoing controversy regarding the continued storage of the smallpox virus by labs in the US and Russia, as any accidental or deliberate release could create a new epidemic for persons born after or in the late 1980 s due to the cessation of vaccinations against the smallpox virus. �
CONTINUED During the 20 th century, there were a series of campaigns to eradicate rinderpest, � A viral disease which infected cattle and other ruminants and belonged to the same family as measles, primarily through the use of a live attenuated vaccine. � The final, successful campaign was led by the Food and Agriculture Organization of the United Nations. � On 14 October 2010, with no diagnoses for nine years, the Food and Agriculture Organization announced that the disease had been completely eradicated, making this the first (and so far the only) disease of livestock to have been eradicated by human undertakings. �
HOW ERADICATION WAS MADE POSSIBLE? � Eradication was accomplished with a combination of � focused surveillance � quickly identifying new smallpox case � and ring vaccination.
RING VACCINATION � “Ring vaccination” meant that anyone who could have been exposed to a smallpox patient was tracked down and vaccinated as quickly as possible, effectively corralling the disease and preventing its further spread.
� The CONTINUED epidemiological factors which have led to eradication of smallpox; these could form the basis for eradication for other disease: 1. No known animal reservoir. � 2. No long-term carrier of the virus. � 3. Life-long immunity, after recovery from the disease. � 4. Simple detection of cases , the rash was so characteristic and occurred in visible parts of the body. � 5. Persons with subclinical infection did not transmit the disease � 6. Vaccine highly effective, easily administered, heat stable, and confers long term protection � 7. International cooperation �
ONGOING ERADICATION PROGRAMS � 1 -Dracunculiasis; guinea worm disease It is a painful and disabling parasitic disease caused by a worm, Dracunculus medinensi. � It is spread through consumption of drinking water infested with copepods hosting the larvae. � Guinea worm disease is set to become the second human disease in history, after smallpox, to be eradicated. � It will be the first parasitic disease to be eradicated and the first disease to be eradicated without the use of a vaccine or medicine �
CONTINUED � Eradication efforts have been based : 1. On making drinking water supplies safer (e. g. through treating the water with larvicide). 2. Control of infection. 3. Education for safe drinking water practices.
CONTINUED � The original goal for eradication was 1995. � Two decades of eradication efforts have reduced guinea worm's global incidence to: � more than 99. 99% to 126 cases in 2014, down from an estimated 3. 5 million in 1986
MEASLES � It is an airborne disease, spreads easily through the coughs and sneezes of those infected , and contact with saliva or nasal secretions. � Nine out of ten people who are not immune and share living space with an infected person catch it. � The measles vaccine is effective at preventing the disease � Vaccination has resulted in a 75% decrease in deaths from measles between 2000 and 2013 with about 85%of children globally being currently vaccinated.
CONTINUED � � � In 2009 the regional committee for Africa agreed a goal of measles elimination by 2020 Europe had set a goal to eliminate measles transmission by 2010, but couldn’t succeed due to the MMR vaccine controversy so they have set a new target of 2015 but still not achieved. The Americas set a goal in 1994 to eliminate measles transmission by 2000, and successfully achieved regional measles elimination in 2002. As of February 2015, measles is no longer eliminated in the US. From January 1 to April 10, 2015, 159 people were reported to have measles.
CONTINUED � � � � � Challenges Funding issues specially for the follow-up campaigns Inadequate number and qualification of staff Competing priorities: Polio eradication Pockets of susceptible populations/groups Hard to reach populations in low income countries – Pockets in countries with big expatriate population Security situation: rapidly deteriorating in the EMR Delayed implementation of planned activities Opportunities Financial support from international partners Interest of the countries Polio infrastructures
3 -POLIOMYELITIS (POLIO) The disease of poliomyelitis has a long history. � The first example may even have been more than 3000 years ago. � The World Health Assembly launched the Global Polio Eradication Initiative (GPEI) in 1988 � Since the GPEI was launched, the number of cases has � fallen by over 99%. � Since 2013, only three countries in the world remain polioendemic: Nigeria, Pakistan and Afghanistan
THE GLOBAL POLIO ERADICATION INITIATIVE (GPEI) Objectives �To interrupt transmission of wild poliovirus as soon as possible �To achieve certification of global polio eradication �To contribute to health systems development and strengthen routine immunization and surveillance for communicable diseases
HOOKWORM � � � Hookworm infection is caused by the transmission of the hookworm parasite common in warmer climates. Hookworm larvae live in soil and typically enter humans through the soles of their feet. Hookworm eradication campaign was started at US in 1909. The Rockefeller Sanitary Commission (RSC) was created with the intention of eliminating the disease across the region. By implementing a three-pronged approach, including mapping the disease, curing patients, and providing education. RSC dramatically reduced the disease burden.
CONTINUED � � � � � 700 million people worldwide, including 44 million pregnant women. Tropical or sub-tropical environments in poverty-stricken areas of Africa, Latin America, Southeast Asia and China. 2001: WHO adopted a resolution aimed at the deworming of 75% of all at-risk school-age children by 2010. A hookworm vaccine is currently in Phase I clinical The 2012 WHO Road Map added 75% coverage of all at-risk pre-school-age children. In United States, elimination of hookworm had been attained.
CONCLUSION � It is useful to consider the successful eradication programs, these programs could form the basis for eradication for other disease. � Both biological and technical features of the disease should be considered before starting eradication program � We have to put in our knowledge the economic , social and political issues before setting a specific global target date for any eradication program.
USEFUL LINKS WHO https: //ourworldindata. org/eradicationofdiseases/ http: //www. nejm. org/doi/full/10. 1056/NEJMra 12 00391#t=article http: //www. iflscience. com/healthandmedicine/were-close-achieving-secondever-globaleradication-human-disease/
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