* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download - Catalyst
Hepatitis B wikipedia , lookup
Chagas disease wikipedia , lookup
Tuberculosis wikipedia , lookup
Neonatal infection wikipedia , lookup
Oesophagostomum wikipedia , lookup
Traveler's diarrhea wikipedia , lookup
Microbicides for sexually transmitted diseases wikipedia , lookup
Typhoid fever wikipedia , lookup
Rocky Mountain spotted fever wikipedia , lookup
Middle East respiratory syndrome wikipedia , lookup
Epidemiology of HIV/AIDS wikipedia , lookup
Gastroenteritis wikipedia , lookup
Onchocerciasis wikipedia , lookup
Plasmodium falciparum wikipedia , lookup
Hospital-acquired infection wikipedia , lookup
Visceral leishmaniasis wikipedia , lookup
African trypanosomiasis wikipedia , lookup
Marburg virus disease wikipedia , lookup
Schistosomiasis wikipedia , lookup
Leptospirosis wikipedia , lookup
Coccidioidomycosis wikipedia , lookup
Sexually transmitted infection wikipedia , lookup
Neglected tropical diseases wikipedia , lookup
War AND Infectious Disease Consequences Learning objectives • Students will be able to identify why war predisposes combatants and civilians to outbreaks of infectious diseases • Students will be able to discuss specific examples of infectious diseases aggravated by war • Students will be able to recognize how conflict-associated migration influences infectious diseases • Students will be able to identify how conflict promotes the emergence or re-emergence of infectious diseases • Students will be able to understand how conflict disrupts disease control and elimination programs Key definitions • Infectious disease (ID): Communicable diseases spread by human contact with organisms such as bacteria, viruses, fungi or parasites • Vector: Transmitters of disease-causing organisms, carrying pathogens from host to host • Incidence: Number of new cases in a fixed time period/Number of people at risk • Prevalence: Number of people with the disease at a given time/Number of people at risk • Endemic: The constant presence and/or usual prevalence of a disease or infectious agent in a population within a geographic area • Epidemic: An increase, often sudden, in the number of cases of a disease above what is normally expected in that population in that area Key definitions (continued) • Elimination: Reduction to zero of the incidence of disease in a defined geographical area • Eradication: Permanent reduction to zero of the worldwide incidence of infection • Sexually transmitted infection (STI): IDs spread through sexual behavior and intercourse • Zoonotic: An ID that is transmitted from animals to humans, sometimes through a vector • Standardized mortality ratios (SMR): The ratio of observed deaths in the study group to expected deaths in the general population • Case fatality rate (CFR): The risk of death of a certain disease, if infected. Calculated as the number of infected individuals who die/all infected individuals How does war lead to infectious diseases? • Conflict often results in increased exposure to infectious agents or contact with vectors • Violence results in reduced access to preventative interventions • Conflict may lead to the displacement of populations into temporary communities with overcrowding and inadequate shelters, unsafe safe water and sanitation • In post-conflict situations, populations may have high rates of illness and mortality due to the breakdown of health systems, flight of trained staff, failure of existing disease control programs, and destroyed infrastructure (more in week XX) • Populations are more vulnerable to infection and disease because of high under-nutrition or malnutrition, low vaccine coverage, or long-term stress • Consequences of war can persist long after the conclusion of war due to chronic lack of investment in health, education, and public works How does war lead to infectious diseases? Fürst T, Raso G, Acka CA, Tschannen AB, et al. (2009) Dynamics of Socioeconomic Risk Factors for Neglected Tropical Diseases and Malaria in an Armed Conflict. PLoS Negl Trop Dis 3(9) A historical perspective: Death attributed to the American Civil War Smallman-Raynor, M.R., Cliff A.D., (2004)War Epidemics: An Historical Geography of Infectious Diseases in Military Conflict and Civil Strife. As other causes of death decrease overtime, war and IDs are always linked Time series of median standardized mortality ratios by causes of death Group 1: Alimentary TB Pleurisy CNS syphilis Bone, joint TB Measles All other syphilis Genito-urinary system Chronic nephritis Nephritis and nephrosis Group 3: Lobar pneumonia Scarlet fever Typhoid and paratyphoid Gonococcal infection Mental illness Homicide, suicide, war injury Poliomyelitis Meningococcal infections Group 3A: Anthrax Malaria Typhus Smallpox Yellow fever Plague Cholera War injury* Homicide and war injury* Group 2: Dysentery Syphilis, general paralysis TB of meninges All pneumonia All respiratory diseases Tetanus Bronchopneumonia Septicemia/pyaemia Tabes dorsalis syphilis Non-meningococcal meningitis Group 4: Influenza Typhoid fever Whoo[ing cough Diphtheria All syphilis Rheumatic fever Venereal disease Other TB Group 5: Gastroenteritis Acute nephritis Primary pneumonia All infections Respiratory TB All TB Non-respiratory TB Skin diseases Smallman-Raynor, M.R., Cliff A.D., (2004)War Epidemics: An Historical Geography of Infectious Diseases in Military Conflict and Civil Strife. Oxford University Press, Oxford, Overlap between war and poverty Keep this map in mind when we look at disease endemicity…. Key examples of infectious disease consequences of war The example of HIV Human Immunodeficiency Virus (HIV) is a retrovirus that attacks CD4 immune system cells. As the immune system weakens, infected individuals become more at risk of infection by other diseases. The most advanced form of HIV is Acquired Immunodeficiency Syndrome (AIDS). HIV is not curable, but the progression can be slowed with antiretroviral treatment. HIV is transmitted sexually (anally or vaginally), through blood transfusions, thrugh shared contaminated needles, and between mother and child during pregnancy, childbirth, or breastfeeding. Personal security Economic security HIV is a matter of… Communal security International security National security -- International Crisis Group “HIV/AIDS as a Security Issue” 2001 Report The example of HIV 2010 HIV prevalence Source: UNAIDS 2011 HIV incidence increases during conflict due to… • in resources necessary for preventing HIV transmission (ex. condoms) • in access to health care, including safe blood supplies and social Decrease services (ex. antenatal care) • in breakdowns in family and other social and community structures • in use of sexual and gender-based violence as weapons during conflict, including coerced sex with persons infected with HIV (more in week XX) Increase • in sexual interactions between civilians and combatants; in many countries the HIV prevalence rate is 2-5 times greater amongst armed personnel relative to civilians • in levels of commercial or transactional sex Smith, A (2002) HIV/AIDS and Emergencies : Analysis and Recommendations for Practice Network HPN Paper 38, Overseas Development Institute, London HIV incidence increases during conflict due to… -- Video: A former soldier's experience with HIV in the DRC In conflict affected areas of Eastern DRC, HIV prevalence is as high as 20%. In the rest of the DRC HIV prevalence is 4% HIV infected individuals are at risk of worsening health because… HIV+ people may • People are less likely to seek counseling and testing services when there is a lack of confidentiality, asylum is not negotiated, not know their and there is chance of refoulment status HIV+ people may • Because health systems and medicine supplies are disrupted, HIV positive individuals may not be able to access the antiretroviral not be able to therapies that they need to stay healthy access treatment HIV+ pregnant • Pregnant women may not have access to antenatal care, and prevention of mother to child transmission (PMTCT) of HIV women not on programs will be disrupted; more children may be exposed to or treatment at ↑ infected by HIV during pregnancy, birth, and breastfeeding transmission risk • Treatment and prophylaxis for opportunistic infections such as Opportunistic tuberculosis (TB) or pneumonia may not be readily available infections will go untreated Protection of HIV-infected or vulnerable populations during conflict requires… 1 Health systems should try to provide condoms, antiretrovirals, and other preventative resources throughout and following a conflict 2 Safe blood supplies should be established or provided through the humanitarian response 3 Confidential HIV testing should be available to all individuals affected by conflict, but not mandatory 4 Guarantee that access to asylum procedures and right of return will not be contingent on HIV status 5 Displaced HIV positive persons should have access to public-sector programs in their area of displacement 6 HIV testing, counseling, and treatment services should be integrated into the core humanitarian response to conflict emergencies The example of neglected tropical diseases • NTDs are chronic, disabling, and disfiguring conditions that affect the world’s most marginalized populations • More than 1 billion people are in need of treatment for NTDs worldwide • NTDs are associated with poverty, breakdowns in health infrastructure, and inadequate access to safe water and sanitation • Because they disproportionately impact the poor, they are “neglected” from research NTD EXAMPLES Lymphatic Filariasis Onchocerciasis Schistosomiasis Soil-transmitted helminths Trachoma Disease Cause Anopholes mosquito vector Impact on poverty Annual productivity loss of $3.1 billion In Africa Treatment Albendazole + ivermectin Blackfly vector Ivermectin Fresh water snail intermediate host Poor access to water, sanitation, and hygiene Poor access to water, sanitation, and hygiene 45.4 days of work are lost annually in infected individuals Income decreases by 40% in infected adults Annual global economic cost of trachoma is $2.9 billion Praziquantel Albendazole Azithromycin The example of neglected tropical diseases The 17 neglected tropical diseases (NTDs): 2013 NTD Endemicity : WHO 2013 1 disease 4 diseases 2 diseases 5 diseases 3 diseases 6 diseases 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. Buruli Ulcer Chagas disease Dengue Guinea-worm Echinococcosis Trematodiases Sleeping sickness Leprosy Lymphatic filariasis Onchocerciasis Leishmaniasis Rabies Schistosomiasis STH Tapeworm Trachoma Yaws War affects NTDs by…. Conflict increases exposure to infectious NTD agents NTD incidence Conflict results in increased transmission and more severe illness Decrease in basic health infrastructure Widespread disability and morbidity Political and social instability Increase in poverty and inequity Conflict and violence Conflict increases susceptibility to disease (ex. malnutrition The example of malaria • Malaria is a parasitic disease spread by the bite of an infected Anopholes mosquito • Malaria cause severe fever, headache, and muscle ache due to rapid destruction of red blood cells • In 2010, 219 million clinical malaria cases and 660,000 malaria deaths occurred, mostly amongst children living in endemic countries in Africa • Malaria can be treated with antimalarials and prevented by sleeping under long lasting insecticide treated nets (LLIN) or removing mosquito breeding sites • Resistance to treatment is increasing, largely due to poor adherence to drugs How can families maintain preventative practices like sleeping under an LLIN during times of conflict? http://www.theguardian.c om/society/2012/apr/05 The example of malaria 2009 estimated number of malaria cases per 1,000 population Cibulskis RE, Aregawi M, Williams R, Otten M, et al. (2011) Worldwide Incidence of Malaria in 2009: Estimates, Time Trends, and a Critique of Methods. PLoS Med 8(12): War affects malaria by… 1 Weakening vector control programs, allowing infected mosquitos to spread 2 Forced migration leads to exposure of nonimmune individuals to malaria endemic areas 3 Environmental destruction encourages mosquito breeding and removes natural predators Local parameter estimates for relationship between 2007 malaria prevalence and number of battles occurring in the DRC within 100 km since 1994 Messina et. al. 2011 “Population, behavioural and environmental drivers of malaria prevalence in the Democratic Republic of Congo” Malaria Journal 10:161 The example of tuberculosis • Tuberculosis (TB) is a very contagious bacterial disease that is spread through the air (ex. coughing) from person to person • TB affects the lungs and can spread to other organs, if left untreated it is usually fatal • People who are immunocompromised with HIV are at increased risk of infection TB around the world • A study of 36 conflicts found that the TB notification rate before conflicts was 81.9 per 100,000 and after conflicts was 105.1 per 100,000. After 2.5 years following the outbreak of conflict, TB rates returned to pre-conflict levels (Drobniewski and Verlander, 2000) • During the 1980s war in Afghanistan, TB incidence increased because TB control activities ceased. After the war, the situation improved, but by 1999 the incidence of active TB was still high (278 per 100,000) and only 10 percent of TB patients received directly observed therapy (DOTS) (Kahn and Laaser, 2002) • During the 1998 civil war in Guinea-Bissau TB patients who received irregular or no treatment had a 3-fold increase in mortality, and HIV-positive patients with TB had an eight-fold increase in mortality (Gustafson et al., 2001) • A study in East Timor found that restoration of TB services during the 5 years post-conflict was primarily due to the structure and experience of a local NGO, and the commitment and flexibility of local personnel and international advisors (Martins et al., 2006) Levy, Barry (2010) “Armed Conflict and Infectious Disease” Infectious Disease Movement in a Borderless World: Workshop Summary. National Academy of Sciences. Diseases associated with migration Migration influences infectious disease because… • Migrants may have no immunity to diseases endemic in the new area • Migrants may bring with them diseases that are common in their former home but which are not endemic in the new area • Migrants are stressed, often physically and emotionally, and behaviors in transition may be different from when in their former home Refugees carry malaria to Thailand Burma Large reservoir of malaria infection in Asia Promotes spread of MDRmalaria in Asia Refugees return with multi-drug resistant malaria from Thailand Thailand Large reservoir of resistant malaria in Asia Beyrer and Lee (2008) “Responding to infectious diseases in Burma and her border regions” Conflict and Health,2:2 WWI and the 1918 Spanish Influenza • The 1918 influenza killed 500 million people (3-5% of the world’s population) • The disease spread in part due to close quarters & massive troop movements during WWI • Some speculate that soldiers’ immune systems were weakened due to malnourishment, increasing their susceptibility to disease and the speed of virus mutation • Flu broke out in Fort Riley, Kansas on March 4th and spread to Queens, NY by March 11th Global diffusion of pandemic influenza, March-November 1919 Spring/Summer 1918 Fall 1918 Smallman-Raynor, M.R., Cliff A.D., (2004)War Epidemics: An Historical Geography of Infectious Diseases in Military Conflict and Civil Strife. Oxford University Press, Oxford, 805pp Migration of combatants Diseases associated with U.S. military service in the Gulf War Malaria: Transmitted by mosquitoes. Symptoms include chills, fever, and sweats Brucellosis: A bacterial disease with symptoms such as profuse sweating and joint and muscle pain. The illness may be chronic and persist for years Campylobacter Jejuni: A disease with symptoms such as abdominal pain, diarrhea, and fever Coxiella Burnetii (Q Fever): A bacterial disease with symptoms such as fever, severe headache, and gastrointestinal problems such as nausea and diarrhea. In chronic cases, the illness may cause inflammation of the heart Tuberculosis: Disease that primarily affects the lungs and causes symptoms such as chest pain, persistent cough (sometimes bloody), weight loss and fever Nontyphoid Salmonella: A condition characterized by symptoms such as nausea, vomiting, and diarrhea Shigella: Characterized by symptoms such as fever, nausea, vomiting, and diarrhea Visceral Leishmaniasis: Parasitic disease characterized by symptoms such as fever, weight loss, enlargement of the spleen and liver, and anemia. The condition may be fatal if left untreated West Nile Virus: Spread by mosquitoes characterized by symptoms such as fever, headache, muscle pain or weakness, nausea, and vomiting http://www.publichealth.va.gov/exposures/gulfwar/infectious_diseases.asp#sthash.QgkmRgQp.dpuf Dengue Fever • Dengue fever is a viral disease spread by the bite of the Aedes mosquitos. Dengue can also be spread through untested blood supplies. • The disease causes severe, acute joint pain and fever • There is no treatment for dengue, but early diagnosis and clinical care decrease the risk of mortality • Dengue increased in South-East Asia during WWII and the immediate post-war period, due to the movement of infected soldiers and different virus strains • The U.S. army used a quantitative algorithm to identify the biggest threat to the health of deployed soldiers globally; dengue is #3 (after malaria and bacterial diarrhea) Civilians are affected by the abandonment of vector control programs during wartime; Mosquitos breed in used tires and other discarded trash containing standing water, often perpetuated by violence Gibbons, R, et. al. (2012) “Dengue and US Military Operations from the Spanish– American War through Today”. Emerging Infectious Diseases,18:4 Dengue Fever “The 65th infantry battalion cleans up streets with residents in Marawi City (Phillipines) to prevent the rise of dengue fever cases. In the past few weeks, at least 60 persons including 7 soldiers have already been infected and remain in the hospital” (Photo by Richel Umel) http://news.pecojon.org/army-marawi-folks-wage-war-on-garbage/ Emerging Infectious Diseases Emerging Infectious Diseases include… 1 New infections resulting from changes or evolution of existing organisms 2 Known infections spreading to new geographic areas or populations 3 Previously unrecognized infections appearing in areas undergoing ecologic transformation 4 Old infections reemerging as a result of antimicrobial resistance in known agents or breakdowns in public health measures - CDC Journal of Emerging Infectious Diseases Emerging Infectious Diseases include… 1 New infections resulting from changes or evolution of existing organisms • Spread by non-human primates and fruit bats, Marburg is a hemorrhagic fever that results in fever, rash, vomiting, diarrhea, and massive hemorrhaging • An outbreak of Marburg fever occurred in northeastern DRC (controlled by Congolese rebels and Ugandan soldiers) from 1998- 2000 • This was the first large outbreak in a rural area, with a CFR of 83% 2 Known infections spreading to new geographic areas or populations 3 Previously unrecognized infections appearing in areas undergoing ecologic transformation 4 Old infections reemerging as a result of antimicrobial resistance in known agents or breakdowns in public health measures Bausch DG, et. al. International Scientific and Technical Committee for Marburg Hemorrhagic Fever Control in the Democratic Republic of the Congo. Marburg hemorrhagic fever associated with multiple genetic lineages of virus. N Engl J Med. 2006;355:909–19. Emerging Infectious Diseases include… 1 New infections resulting from changes or evolution of existing organisms 2 Known infections spreading to new geographic areas or populations • Malaria had been almost eliminated in Tajikistan in the early 1960s • Civil conflict during 1992–1993 led to massive population displacement; more than 100,000 persons fled to Afghanistan, reintroducing malaria parasites when they returned in 1994 • An outbreak ensued, which reestablished Plasmodium falciparum malaria in Tajikistan for first time in 35 years • By 1997, 200,000–500,000 cases were estimated per year. Malaria has subsequently been controlled in Tajikistan 3 Previously unrecognized infections appearing in areas undergoing ecologic transformation 4 Old infections reemerging as a result of antimicrobial resistance in known agents or breakdowns in public health measures Aliev SP. Malaria in the Republic of Tajikistan [in Russian]. Med Parazitol (Mosk).2000;2:27–9 Emerging Infectious Diseases include… 1 New infections resulting from changes or evolution of existing organisms 2 Known infections spreading to new geographic areas or populations 3 Previously unrecognized infections appearing in areas undergoing ecologic transformation • Hepatitis E is a liver disease caused by the hepatitis virus, resulting in jaundice, fever, and vomiting • An outbreak of hepatitis E occurred in Darfur, Sudan in 2004, with an attack rate of 3.3% and a CFR of 1.7% • More than 1 million people were displaced during an extreme drought, resulting in little access to safe water and adequate sanitation • The outbreak subsequently spread to Chad when Sudanese refugees fled Darfur 4 Old infections reemerging as a result of antimicrobial resistance in known agents or breakdowns in public health measures Guthmann JP, et. al. , A large outbreak of hepatitis E among a displaced population in Darfur, Sudan, 2004: the role of water treatment methods. Clin Infect Dis. 2006 Emerging Infectious Diseases include… 1 New infections resulting from changes or evolution of existing organisms 2 Known infections spreading to new geographic areas or populations 3 Previously unrecognized infections appearing in areas undergoing ecologic transformation 4 Old infections reemerging as a result of antimicrobial resistance in known agents or breakdowns in public health measures • Shigella dysenteriae is a bacterial disease that causes severe diarrhea and malnutrition, spread through fecal-oral routes • An outbreak of Shigella dysenteriae occurred in a Rwandan camp for Burundian refugees fleeing civil war in 1993 • <50% of patients complied with their 5-day antimicrobial drug treatment • An attack rate of 32% was observed with a CFR of 4% Paquet C, Leborgne P, Sasse A, Varaine F. An outbreak of Shigella dysenteriae type 1 dysentery in a refugee camp in Rwanda Geographic distribution of recent emerging or reemerging infectious disease outbreaks and countries affected by conflict, 1990–2006 Countries in yellow were affected by violence during this period Michelle Gayer, Disease Control in Humanitarian Emergencies, Communicable Diseases Cluster, World Health Organization, Geneva 27, Switzerland; Conflict and disease eradication efforts Poliomyelitis • Polio is a viral disease that invades the brain, spinal chord, and can cause paralysis • Polio is spread through person-to-person contact • There is no cure for polio, but it can be prevented by a childhood vaccine • Elimination of polio from the Western hemisphere is one of the greatest public health achievements of this century Polio in 1988 Polio in 2006 http://www.polioeradication.org/Aboutus/Progress.aspx Poliomyelitis • Low vaccine coverage in war-endemic countries has led to reemergence of poliomyelitis • Increased incidence has also pushed back global polio eradication targets • 2013 has seen an increase in the spread of polio, including infections in Syria and strains detected in Egypt and Israel • February 12, 2014: First case of polio occurs in Kabul since 2001 www.thehindu.com Poliomyelitis • Ceasefires have been called to provide polio vaccines during times of conflict • “Days of tranquility” require armed forces to cease fighting to accommodate health worker movement • In 2001, the UN negotiated a week-long ceasefire in Afghanistan that enabled 5.7 million child polio vaccinations nationwide • In order to prevent polio recrudescence in Syria, officials are calling for a ceasefire to vaccinate 500,000 children Oral polio vaccine campaign in Afghanistan (2013) Video: Negotiating a ceasefire in Syria m.afghanistan-today.org Guinea Worm • Guinea worm disease, or dracunculiasis, is caused by roundworm parasites • It is spread by drinking water containing copepods—tiny crustaceans—carrying the worm's larvae; after a year, mature worm emerges from the skin, usually at the foot The Carter Center (2013) Guinea Worm How might the 2013 outbreak of civil violence in South Sudan affect the eradication activities discussed in this video? Video of the Carter Center's guinea worm eradication efforts Malnutrition and infectious diseases Malnutrition • Malnutrition refers to substandard nutritional status of a person (both under and over nutrition). We are refer to under-nutrition, specifically • Malnutrition can be acute or chronic • Both macronutrients and micronutrients affect immune function conflict.lshtm.ac.uk Malnutrition promotes infection by compromising the immune system Infectious disease Malnutrition IDs promote malnutrition by interfering with the metabolism of key nutrients Wang et. al. (2006)“HIV InSite Knowledge Base Chapter” UCSF Malnutrition Malnutrition Socioeconomic and political instability Impaired child development Compromised immunity Poverty Energy loss/reduced productivity Infection and disease Malnutrition Example: Post-Gulf War sanctions in Iraq • The 1991 Persian Gulf war was followed by international sanctions by the United States against Iraq • The sanctions resulted in widespread damage to water and sanitation systems, resulting in epidemics such as cholera, typhoid, gastroenteritis, malaria, meningitis, measles, polio, and hepatitis (all of which occurred predominantly amongst children) • The sanctions also resulted in high rates of malnutrition by limiting food imports and decreasing food production and processing domestically • Research demonstrated that the Iraq sanctions predominantly affected the poor and 2 years after the war most Iraqis faced severe hunger (Birn et. al. 2009) • Rampant malnutrition and destruction of infrastructure (and resulting IDs) combined to drastically increase child mortality • By 1998, an estimated 500,000 “excess deaths” of Iraqi children had occurred (Arya et.al., 2007) Ostrach et. al. (2013) “Syndemics of war- Malnutrition infectious disease interactions and the unintended consequences of intentional war policies.” Annals of Anthropological Practice Malnutrition Example: Post-Gulf War sanctions in Iraq By affecting nutrition, water quality, and sanitation infrastructure, it is estimated that post-Gulf War sanctions caused at least 4 civilian deaths for every Iraqi soldier killed in battle (Garfield 1999) http://www.scn.org/ccpi/UnicefMay2001.html Summary How to prevent conflict-associated infectious diseases • Look for potential associations between infectious diseases and conflict and inequality; disconnecting causal social influences from biological processes undermines disease control efforts • Invest in strong surveillance systems to detects outbreaks before they become widespread, particularly amongst soldiers and other migratory populations • Work with political and health organizations to ensure that key health activities are carried out despite conflict (ex. polio vaccination ceasefires) • Ensure that preventative activities (ex. HIV testing and LLINs) are available to displaced persons during and post-conflict • Prevent war; if you want health for all then work for justice for all