Communicable Diseases
Measles, diarrheal diseases, ARIs, and in some cases, malaria are the primary
causes of morbidity and mortality among refugee and displaced populations
(1,16,41). (Figure 4), (Figure 5), and (Figure 6) illustrate
patterns of mortality typical among those found in refugee camps. Other
communicable diseases, i.e., meningococcal meningitis, hepatitis, typhoid
fever, and relapsing fever have also been observed among refugee populations;
however, the contribution of these illnesses to the overall burden of disease
among refugees has been relatively small.
Densely populated camps with poor sanitation, inadequate clean water
supplies, and low-quality housing all contribute to the rapid spread of
disease in refugee settings. In addition, the interaction between
malnutrition and infection in these populations, particularly among young
children, has contributed to the high rates of morbidity and mortality from
communicable diseases. Available and affordable technology could prevent much
of this morbidity and mortality either through primary prevention (e.g.,
immunization, adequate planning, and sanitation) or through appropriate case
management (e.g., treatment of dehydration caused by diarrhea with oral
rehydration salts and continued feeding).
Measles
Outbreaks of measles within refugee camps have been common and have caused
many deaths. Low levels of immunization coverage, coupled with high rates of
undernutrition and vitamin A deficiency, have played a critical role in the
spread of measles and the subsequent mortality within some refugee camps.
Measles has been one of the leading causes of death among children in refugee
camps. In addition, measles has contributed to high malnutrition rates among
those who have survived the initial illness. Measles infection may lead to or
exacerbate vitamin A deficiency, compromising immunity and leaving the
patient susceptible to xerophthalmia, blindness, and premature death (42). In
early 1985, the crude, measles-specific death rate in one eastern Sudan camp
reached 13/1,000/month; among children less than 5 years of age, the
measles-specific death rate was 30/1,000/month. Over 2,000 measles deaths
were reported in this camp from February through May 1985. (Figure 9)
illustrates the proportion of all deaths that were due to measles in this
camp during the course of the outbreak (16). The CFR was reported to be 33%
during this outbreak; however, mild cases may have been underreported. Large
numbers of measles deaths have been reported in camps in Somalia, Bangladesh,
Sudan, and Ethiopia (1). Mass immunization campaigns were effective in
reducing the measles morbidity and mortality rates in camps in both Somalia
and Thailand (16). Measles outbreaks probably did not occur during certain
other major refugee emergencies (e.g., Somalis in Ethiopia in 1989; Iraqis in
Turkey in 1991), because immunization coverage rates were already high in
those refugee populations before their flight (9,10).
Diarrheal diseases
Diarrheal diseases are a major cause of morbidity and mortality among refugee
and displaced populations, primarily because of the inadequacy of the water
supply (both in terms of quality and quantity), and the insufficient and
poorly maintained sanitation facilities. In eastern Sudan in 1985, between
25%-50% of all deaths in four major camps were attributed to diarrheal
diseases. In Somalia (1980), Malawi (1988), and Ethiopia (1989), between
28%-40% of all deaths in refugee camps were attributed to diarrhea (1).
Between March and October 1991, 35% of deaths among Somali refugees in the
Liboi camp in Kenya were caused by diarrhea. Among Central American refugees
in Honduras, diarrheal diseases were responsible for 22.3% of mortality among
children less than 5 years of age during a 3-year period (43). In April 1991,
in camps for Iraqi refugees on the Turkish border, approximately 70% of all
patients arriving at clinics had diarrhea (10). Of these, approximately 25%
complained of bloody diarrhea during the first 2 weeks of April. (Figure 10
) shows the gradual decline in diarrheal disease among clinic outpatients at
a Kurdish refugee camp in Turkey.
Improvements in camp sanitation and water supply were probably responsible
for this trend. Although the etiologies of diarrheal illness during refugee
emergencies have not been well documented, the responsible pathogens are most
likely to be the same agents that cause diarrhea in non-refugee populations
in developing countries. In one study in a camp for famine victims in
Ethiopia, of 200 patients with diarrhea, 15.6% had positive cultures for
Escherichia coli (pathogenicity not specified by authors), 3.5% for Shigella
spp., and 2% for Salmonella spp. (44).
Cholera
Outbreaks of cholera have occurred in several refugee populations, although
overall, other diarrheal diseases have probably caused many more deaths than
cholera. In addition to the morbidity and mortality directly caused by
cholera, epidemics of this severe disease cause serious disruption to camp
health services. Outbreaks of cholera have been reported in refugee camps in
Thailand (16,45), Sudan (46), Ethiopia (11-12), Malawi (47), Somalia (48),
and Turkey (10). The Somali Refugee Health Unit reported 6,560 cases of
cholera and 1,069 cholera deaths in 1985. During the course of the epidemic,
one camp (Gannet) experienced a CFR of 25%. The CFR in the remaining camps
was 2.9%, with some areas reporting a CFR of less than 1% (Figure 11)
(48). During the same year, two adjacent refugee camps in the Sudan reported
a total of 1,175 cases of cholera with 51 deaths (CFR = 4%) over the course
of a 2-week epidemic (46). Mozambican refugees in Malawi have been especially
vulnerable to cholera; 20 separate outbreaks have been reported in Malawian
camps since 1988 (49). Outbreak investigations have identified polluted water
sources, shared water containers and cooking pots, lack of soap, failure to
reheat leftover food, and possibly contaminated food (dried fish) as
important risk factors for infection. Nearly 2,000 cases were reported among
80,000 refugees in one camp (Nyamithutu) during a 4-month period in 1990 (
Figure 12). Among 26,165 new arrivals during this period, 1,651 cases
were reported for an attack rate of 6.3% in this group. The variation in CFRs
between camps reflects the different levels of organizational preparedness,
health worker training and experience, and available resources. One group of
relief workers speculated that high CFRs in some Malawian camps may be
associated with concurrent niacin deficiency, although their hypothesis has
not yet been proven (Moren A, personal communication).
Acute respiratory infections
ARIs are among the leading causes of death among refugee populations. In
Thailand (1979), Somalia (1980), Sudan (1985), and Honduras (1984-1987), ARIs
were cited among the three main causes of mortality in refugee camps,
particularly among children (16,43). Among children less than 5 years of age
in refugee camps in Honduras, respiratory infections were responsible for
slightly greater than 1 of every 5 deaths during a 3-year period (43).
Tuberculosis (TB)
TB is well recognized as a health problem among refugee populations. The
crowded living conditions and underlying poor nutritional status of refugee
populations may foster the spread of the disease. Although not a leading
cause of mortality during the emergency phase, TB often emerges as a critical
problem once measles and diarrheal diseases have been adequately controlled.
For example, 26% of adult deaths among refugees in Somalia in 1985 were
attributed to TB (16). During this time, TB was the third leading cause of
death, and the leading cause among adults (48). In eastern Sudan, between 38%
and 50% of all deaths in two camps were caused by TB during the 9 to 10
months period after the camps opened (16). TB has been cited as a major
health problem among Afghan refugees in Pakistan (CDC. Serdula M, trip
report). Although it may be theoretically easier to ensure patient compliance
with protracted chemotherapy in the confined space of a refugee camp, the
personnel needed to supervise treatment may not be available. In addition,
the uncertain duration of stay, frequent changes of camp locations, and poor
camp organization may hinder TB treatment programs.
Malaria
Malaria is a major health problem in many areas that host large refugee
populations, including Somalia, Sudan, Ethiopia, Thailand, Guinea, Cote
d'Ivoire, Malawi, Pakistan, and Kenya. Malnutrition and anemia, conditions
that are common among refugees, may be directly related to recurrent or
persistent malaria infection or may compound the effects of malaria and lead
to high mortality. Malaria is the leading cause of morbidity among adult
refugees in Malawi and in 1990 caused 18% of all deaths and 25% of deaths
among children less than 5 years of age (CDC, unpublished data). Malaria is
of particular concern w