The CMRs reported in various refugee, internally displaced, and famine-affected (but nondisplaced) populations, respectively, during the emergency phase of relief operations in the past 15 years are listed in ( Table 2), (Table 3), and (Table 4). These rates are compared with baseline CMRs reported for nonfamine-affected and nondisplaced populations, or, in the case of refugees, with CMRs in their country of origin. CMRs in these tables are expressed as deaths per 1,000 per month to reflect the short reporting periods; comparison rates have been extrapolated from annual CMRs published by the United Nations Children's Fund (UNICEF) (13). Although CMRs reported in refugee emergencies have not been adjusted for age and sex, it is unlikely that demographic differences between refugee and non-refugee populations account for the excess mortality found among many of the latter.
Monthly CMRs recorded immediately after the initial influx of Cambodian refugees into Thailand (1979), Ethiopian refugees into Somalia (1980), and Ethiopian refugees into eastern Sudan (1985) were 8.1 to 15.2 times the expected rates. The early death rate among Kurdish refugees in Turkey in April 1991 was 18 times the baseline rates in both Iraq and Turkey. In contrast, among Mozambican refugees in Malawi in 1987, camp-based CMRs were one-third lower than the national CMR reported for Mozambique. A movement of 50,000 refugees from Burundi into Rwanda in 1988 also resulted in minimal mortality once asylum had been attained. The rate of improvement in camp populations has varied considerably. For example, mortality rates decreased rapidly in Cambodian refugee camps in Thailand in 1979-1980 and in the Kurdish camps of Turkey in 1991, but only slow improvement occurred during the initial 8 months in Somalia (1980) and in Sudan (1985). In eastern Ethiopia in 1988-1989, initially low mortality rates among Somali refugees increased after 6 months, reaching a peak at 9 months (Figure 3). Overall, less than 1% of Cambodian refugees in Thai camps died during the first 12 months; 9% of refugees in eastern Sudan died during the same period of time (1).
Political and security factors often obstruct the accurate documentation of death rates among internally displaced populations; however, a few situations have been well documented. In Mozambique (1983), Ethiopia (1984-1985), and Sudan (1988), CMRs estimated by surveillance or population-based surveys of internally displaced persons ranged between 4 and 70 times the death rates in nondisplaced populations in the same country. In the Korem area of Ethiopia, CMRs recorded among camp populations displaced by famine in 1985 were 7-10 times those of settled villagers in a similar highland zone affected by the famine. In Monrovia, the capital of Liberia, the death rate among civilians displaced during the 1990 civil war was 7 times the pre-war death rate (Holland MSF, unpublished data, January 1991).
As in stable populations in developing countries, age-specific death rates in displaced and refugee populations are highest in children less than 5 years of age. A mortality survey of Kurdish refugees at the Turkey-Iraq border during 1991 revealed that 63% of all deaths occurred among children less than 5 years of age, who comprised approximately 18% of the population (11). Although absolute death rates are highest in infants less than 1 year of age, the relative increase in mortality during emergencies may be highest in children 1-12 years of age (1).
A study of 42 refugee populations completed in 1989 examined acute protein energy malnutrition (PEM) prevalence and crude unadjusted monthly mortality rates, gathered from 1984-1988. Analysis of the data showed a strong positive association between PEM prevalence and CMRs. Populations with PEM prevalence rates of less than 5% had a mean CMR of 0.9/1,000/month. Refugee populations with PEM prevalences of greater than or equal to 40%, however, experienced a mean CMR of 37/1,000/month with a range of 4/1,000/month to 177/1,000/month ( Figure 7). The rate ratio between the lowest and highest CMR values was 40.7 (14).
The close correlation between malnutrition prevalence and crude mortality during a relief operation for Somali refugees in eastern Ethiopia in 1988-1989 is clearly demonstrated in (Figure 8. Malnutrition prevalence was estimated by serial, cross-sectional, cluster sample surveys of children less than 5 years of age, and monthly death rates were estimated retrospectively by a population-based survey in August 1989. During the period of high malnutrition prevalence and high mortality (March-May 1989), food rations provided an average of approximately 1,400 kilocalories (kcal)/person/day instead of the recommended minimum of 1,900 kcal/person/day (9). Likewise, in eastern Sudan in 1985, inadequate amounts of food (1,360-1,870 kcal/person/day) were distributed to Ethiopian refugees during the first 5 months after their arrival in the camps. Malnutrition rates, as well as mortality rates, remained high during this period (Figure 3) ( Table 5). In addition, a severe measles outbreak in the Sudanese camps added to the high mortality (21).