Prevalence of Eosinophilia and Parasites
in a Newly Arrived Refugee Population
Thomas Herchline, MD, Brandon Kohrs, DO
Public Health - Dayton & Montgomery County and
Wright State University Boonshoft School of Medicine
#1688
Eosinophilia is a major health issue concerning
immigrant populations from parasite endemic regions.
The presence of eosinophilia is most commonly due to
parasite infections in this group. This study was
undertaken to assess the prevalence of eosinophilia and
the prevalence of parasitic infections in refugees being
resettled in Dayton, Ohio.
This was a retrospective chart review of all refugees
who were evaluated at Public Health – Dayton &
Montgomery County (Ohio) from 2009-2013. Inclusion
criteria was country of origin in Africa, Asia or Middle
East. Evaluation included a single stool examination for
O&P as well as a CBC with automated differential.
Refugees were excluded from the study if there was no
country of origin listed, or for missing lab values.
Eosinophilia was defined as absolute eosinophil count >
500 cells/μL or eosinophil percentage ≥ 7.0.
A total of 637 charts of individuals were reviewed;
39 were excluded from analysis. Of the remaining 598
refugees, 364 were male and 234 female. A total of 300
were from countries in Africa, 211 from the Middle East
and 87 from Asia. The mean age was 29.1; 450 (75.3%)
of refugees were adults (age ≥ 18 yrs). Overall, 197
(32.9%) of the refugees had a positive screen for O&P.
The most common parasite found was Giardia (29),
followed by E. histolytica/dispar (17), Schistosoma (4),
Hookworm (4), Strongyloides (3), Trichuris (3), and
Ascaris (1). Non-pathogens were found in a total of 165
refugees. Eosinophilia was noted in 95 (15.9%) of the
refugees and was associated with the finding of a tissue
parasite in the stool O&P screen.
The percentage of refugees arriving with intestinal
helminth infection was fairly low in this study, as
compared to studies prior to the recommendation for
refugees from sub-Saharan Africa and Asia to receive
empiric therapy with albendazole prior to departure.
Despite the recommendations for pre-departure
treatment, many refugees arrive in the United States with
parasitic infection, and many more have significant
eosinophilia, emphasizing the need for prompt and
thorough screening after arrival in the US.
Introduction
Results
Conclusions
• Eosinophilia is common in immigrants from
parasite-endemic regions such as Sub-Saharan
Africa, the Middle East and Asia
• The majority of patients with parasitic
infections are asymptomatic, necessitating the
use of screening tests including a CBC with
differential looking for eosinophilia
• In 1999, the CDC issued a recommendation for
all refugees from sub-Sahara Africa to receive
presumptive treatment with albendazole
• Subsequently, this recommendation was
extended to other regions and to include
presumptive treatment with ivermectin and
praziquantel
• The top four countries of origin for refugees
arriving in the US in FY 2013 were Iraq,
Burma, Bhutan, and Somalia – each located in
parasite-endemic regions
•
•
•
•
• The percentage of refugees arriving with
intestinal helminth infection was low in this
study, compared to studies prior to the
recommendation for refugees from subSaharan Africa and Asia to receive
presumptive therapy prior to departure
• Despite presumptive therapy, many refugees
arrive in the United States with parasitic
infection, and many more have significant
eosinophilia, emphasizing the need for
prompt and thorough evaluation after arrival
in the US
• The presence of tissue parasites correlated
with eosinophilia
• The presence of non-pathogens in stool was
not associated with eosinophila
• The presence of pathogens or non-pathogens
correlated with lower BMI compared to those
with no parasites
637 charts reviewed; 39 excluded from analysis
364 males and 234 females
300 from Africa, Middle East: 211, Asia: 87
Mean age 29.1; 450 (75.3%) of refugees were
adults (age ≥ 18 yrs)
197 (32.9%) of the refugees had a positive O&P
The most common parasite found was Giardia
Non-pathogens were found in 165 refugees
Eosinophilia found in 95 (15.9%) of refugees and
was associated with finding parasites in stool O&P
•
•
•
•
Pathogens found in O&P Exam
35
30
25
20
15
10
5
0
O&P Findings vs. Eosinophilia Count
Methods
Non-Pathogen
Pathogen
Tissue Pathogen
45%
• A retrospective chart review was done to
evaluate the prevalence of eosinophilia and
parasites in refugees arriving in Dayton
• Refugees from parasite-endemic regions
(Sub-Saharan Africa, Asia, and the Middle
East) were included in the study
• Refugees were excluded from the study if
there was missing data
• Records from the initial medical evaluations
were reviewed for country or origin, age, sex,
height, weight, CBC result, and results of
stool exam for ova & parasites
• Eosinophilia was defined as absolute
eosinophil count > 500 cells/μL or eosinophil
percentage ≥ 7.0
Percent with Parasite
Abstract
Dr Thomas Herchline
128 E Apple St, 2nd Floor WSU DOM
Dayton, OH 45409
937-208-2873; 937-208-2621 (Fax)
References
40%
35%
30%
25%
20%
15%
10%
5%
0%
0 to 499
500 to 999
≥ 1500
1000 to 1499
Absolute Eosinophilia Count (cells/μL)
BMI in Adults and Children
No Parasites
Non-Pathogens
Pathogens
30.0
25.0
20.0
15.0
10.0
5.0
0.0
Adults
Children
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