Transcript - Catalyst

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