Analysis of Enteric Parasites Found in Refugees in Texas,

2000-2005

Bethany Dalene BlackstoneSchool of Biological Sciences

The University of Texas at Austin

Mentors: Jeff Taylor, MPH

Katherine Von Alt, M(ASCP)

Introduction

http://news.bbc.co.uk/2/hi/south_asia/4269507.stm

Estimated Worldwide Prevalence of Parasitic InfectionsInfection Prevalence

Toxoplasmosis 1-2 billion

Ascaris 1 billion

Hookworm disease 800-900 million

Amebiasis 200-400 million

Schistosomiasis 200-300 million

Malaria 200-300 million

Filariasis 250 million

Giardiasis 200 million

Pinworm infection 60-100 million

Strongyloidiasis 50-80 million

Guinea worm infection 20-40 million

Trypanosomiasis 15-20 million

Leishmaniasis 1-2 million

taken from Table 51-1, Schaechter's Mechanisms of Microbial Disease, fourth edition

Overview of Parasitology

Parasites: helminths and protozoa Blood and tissue parasites

malaria Enteric parasites

tapeworm Arthropods

A: thick blood smear of malaria; B: T. solium; images from CDC’s DPDx

A

B

Helminths

Metazoa

Nemahelminthes Platyhelminthes

Trematoda Cestoda

Model Helminth: Trichuris trichiura

Protozoa

Protista

Protozoa

Sacromastigophora

Amoeba

Flagellates

Model Protozoan: Giardia lamblia

A Risk for Populations

Developing countriesTropicsSouthern United StatesInstitutional settings (e.g. daycares)Newly arrived persons

Travelers Immigrants Refugees

http://www.internationalstudies.villanova.edu/students/photocontest/photos/SP04%20photo%20contest/Newly%20Arrived%20Refugees%20Peter%20Dweyer,%20Tibet.jpg

Refugees

Immigration and Nationality Act: person forced to leave home country and unable to return because of persecution

Refugees are not Immigrants Internally displaced

persons

http://www.npr.org/templates/story/story.php?storyId=1976090

http://news.bbc.co.uk/2/hi/south_asia/4269507.stm

The world as you are used to seeing it

http://www.sasi.group.shef.ac.uk/worldmapper/display.php?selected=1

Where are refugees commonly from?

http://www.sasi.group.shef.ac.uk/worldmapper/display.php?selected=14

And where are they going?

http://www.sasi.group.shef.ac.uk/worldmapper/display.php?selected=13

Resettlement to the United StatesPre-departurehealth screeningArrival in USresults of screening sent to

state health departmentsArrival in Texasscreening at refugee

clinics

http://www.irrawaddy.org/aviewer.asp?a=3788&z=9http://www.radiocayman.gov.ky/servlet/page?_pageid=3471&_dad=portal30&_schema=PORTAL30&_mode=3

Refugees entering Texas

Amarillo

Austin

Dallas

HoustonSan Antonio

Abilene

Purpose

To analyze the enteric parasites found in refugees entering the state of Texas between 2000 and 2005

Determine prevalence, demographic characteristics http://www.interaction.org/media/photo2005/DR.html

Materials and Methods

http://www.respecteurope.org/Refugees/tabid/58/Default.aspx

Study Population

Official refugees entering Texas between January 1, 2000 and December 31, 2005

Database of 14,540 specimen entries Analysis carried out using Access, Excel

http://www.respecteurope.org/Refugees/tabid/58/Default.aspx

Specimen submission and screening procedure

Clinics collect stool samples Formalin vial PVA vial

Samples sent to Medical Parasitology Section at TDSHS

Process, ID, and enter in database

Texas Department of State Health Services: Medical Parasitology Section

Laboratory Identification

Formalinwet mounts for cysts and trophs PVAtrichrome for ova

Helminth ID

A. lumbricoides C. sinensis D. latum E. vermicularis F. buski/F. hepatica Hookworm species H. nana S. mansoni S. stercoralis Taenia species T. orientalis T. trichiura Other eggs

A B

C D

A: A. lumbricoides eggs; B: T. trichiura egg; C: F. buski fluke; D: T. saginata adult; images from CDC’s DPDx

Protozoan ID

B. hominis (rare to few, moderate to many)

C. mesnili C. parvum C. cayetanensis D. fragilis E. nana E. coli E. hartmanni E. histolytica E. polecki G. lamblia I. butschlii I. belli T. hominis

A B

C D

A: E. nana cyst; B: E. polecki cyst; C: E. histolytica trophozoite ; D: G. lamblia trophozoites; images from CDC’s DPDx

Refugee Databases

Master Database(Access)

Lab ID(Access)

Refugee Demographics(EpiInfo)

Cleaned Database

Demographic Variables

Overall prevalence Country of origin Area of origin Gender Age Multiple infections City of arrival

http://www.cbc.ca/world/story/2004/12/13/darfur041213.html

Results

http://ec.europa.eu/echo/information/library/refugees/03.htm

Countries of Origin for Refugees in Texas

Percent of Refugees by Area of Origin

UNKNOWN43%

NEAR EAST/SOUTHWEST

ASIA11%

LATIN AMERICA

5%

EASTERN EUROPE

8%

EAST ASIA6%

AFRICA27%

n=14,540

Percent of Refugees by Country of Origin

n=14,540

8%2%

3%

3%

3%

3%4%

5%

5%

6%

7%8%

43%

UNKNOWN

SUDAN

SOMALIA

BOSNIA

CUBA

VIETNAM

AFGHANISTAN

IRAN

LIBERIA

IRAQ

ETHIOPIA

CONGO

LESS THAN 200

Which refugees are going where?

HOUSTON

DALLAS

AUSTIN

AMARIL

LO

SAN ANTONIO

ABILENE

HILLCRO

FT/HO

USTON

TYLER AFRICA

EAST ASIA

EASTERN EUROPE

LATIN AMERICA

NEAR EAST/SOUTHW

EST ASIA

UNKNOW

N

0500

1000150020002500300035004000

NUMBER OF REFUGEES

CITY OF ARRIVAL AREA OF ORIGIN

Breakdown by Area of Origin for Refugees Who Entered Texas by City of Arrival, 2000-2005

Refugees entering Texas…

0

10

20

30

40

50

60

PERCENT OF REFUGEES

AFRIC

A

EAST ASIA

EASTERN EUROPE

LATIN A

MERIC

A

NEAR EAST/S

OUTHW

EST ASIA

UNKNOW

N

AREA OF ORIGIN

Percent by Gender of Refugees Who Entered Texas by Area of Origin, 2000-2005

FEMALE

MALEUNKNOWN

n=14,540

…are not just adults.Percent of Refugees Who Entered Texas by Age, 2000-2005

18-->34(37%)

7-->17(21%)

0-->6(13%)

UNKNOWN(2%)

61+(2%)

35-->60(25%)

n=14,540

Percent of Refugees Positive for Helminths by Area of Origin

(370/3784)

(158/864)

(22/1141)

(32/751)

(94/1488)

0

2

4

6

8

10

12

14

16

18

20

AFRIC

A

EAST ASIA

EASTERN EUROPE

LATIN A

MERIC

A

NEAR EAST/S

OUTHW

EST ASIA

AREA OF ORIGIN

PE

RC

EN

T O

F R

EF

UG

EE

S P

OS

ITIV

E

(0)

(1)

(2)

(4)

(8)

(10)

(13)

(109)

(178)

(178)

(186)

(266)

(317)

0 0.5 1 1.5 2 2.5

Percent of Refugees Positive

D. latum

other eggs

F. buski/F. hepatica

C. sinensis

E. vermicularis

Taenia species

T. orienatlis

S. stercoralis

A. lumbricoides

hookworm species

S. mansoni

T. trichiura

H. nana

Hel

min

ths

Percent of Refugees Positive for Individual Helminth Parasites

n=14,265

Percent of Refugees Positive for Protozoa by Area of Origin

(2469/3784)

(361/864)

(614/1141)

(532/751)

(937/1488)

0

10

20

30

40

50

60

70

80

AFRICA

EAST ASIA

EASTERN EURO

PE

LATIN A

MERIC

A

NEAR EAST/S

OUTHW

EST ASIA

AREA OF ORIGIN

PE

RC

EN

T O

F R

EF

UG

EE

S P

OS

ITIV

E

(2)

(3)

(3)

(3)

(7)

(206)

(568)

(728)

(830)

(1283)

(1912)

(1912)

(1997)

(2979)

(5879)

0 5 10 15 20 25 30 35 40 45

Percent of Refugees Positive

T. hominis

C. cayetanensis

C. parvum

I. belli

E. polecki

C. mesnili

D. fragilis

I. butschlii

E. histolytica

B. hominis (moderate to many)

G. lamblia

E. hartmanni

E. coli

E. nana

B. hominis (rare to few)

Pro

tozo

aPercent of Refugees Positive for Individual Protozoan

Parasites

n=14,265

Gender of Refugees Positive for Helminths and Protozoa Individually, and for Both Helminths and Protozoa

(180)(122)

(4024)(3622)

(462)(330)

0

10

20

30

40

50

60

70

FEMALE (n=6264) MALE (n=7349)

GENDER

PE

RC

EN

T O

F R

EF

UG

EE

S P

OS

ITIV

E

POSITIVE HELMINTHS

POSITIVE PROTOZOA

POSITIVE HELMINTHS & PROTOZOA

Age of Refugees Positive for Helminths and Protozoa Individually, and for Both Helminths and Protozoa

(6)(35) (90) (124) (60)

(141)

(2076)(3096)

(1718)

(795)

(16)(105)

(317)(272)

(101)

0

10

20

30

40

50

60

70

0-->6 (n=1781) 7-->17 (n=2999) 18-->34 (n=5285) 35-->60 (n=3651) 61+ (n=277)

AGE

PE

RC

EN

T O

F R

EF

UG

EE

S P

OS

ITIV

E

POSITIVE HELMINTHS

POSITIVE PROTOZOA

POSITIVE HELMINTHS & PROTOZOA

Percent of Refugees Positive for H. nana by Area of Origin

(41/1488)

(0/751)

(3/864)

(140/33784)

(4/1141)

0

0.5

1

1.5

2

2.5

3

3.5

4

AFRIC

A

EAST ASIA

EASTERN EUROPE

LATIN A

MERIC

A

NEAR EAST/S

OUTHW

EST ASIA

AREA OF ORIGIN

PE

RC

EN

T O

F R

EF

UG

EE

S P

OS

ITIV

E

Percent of Refugees Positive for G. lamblia by Area of Origin

(151/1488)

(56/751)(91/1141)

(436/3784)

(48/864)

0

2

4

6

8

10

12

14

AFRIC

A

EAST ASIA

EASTERN EUROPE

LATIN A

MERIC

A

NEAR EAST/S

OUTHW

EST ASIA

AREA OF ORIGIN

PE

RC

EN

T O

F R

EF

UG

EE

S P

OS

ITIV

E

Conclusions

http://saindarfur.org/darfur_photos/albums/uploads/May/2/refugees_food_line_AFP_5_12_05.jpg

Conclusions

Refugees who entered Texas came from all areas of the world Africa Gender Age

http://www.lnsart.com/JachRefugeeCampSudan.jpg

Most commonly seen parasites

Helminths H. nana—2.22% (317) T. trichiura—1.86% (266) S. mansoni—1.30% (186)

Protozoa (pathogens) G. lamblia—8.99% (1283) B. hominis (moderate to many)—8.92% (1272) E. histolytica—5.82% (830)

Similar Studies

State

(author)

Texas

(current study)

California

(Garg et al.)

Illinois

(Peterson et al.)

Year Jan 2000- Dec 2005 Oct 2001-Jan 2004 July 1998-June 1999

Helminths H. nana (2.2%)

T. trichiura (1.9%)

Hookworm (2%)

A. lumbricoides (1.3%)

S. stercoralis (1.3%)

N/A

Protozoa G. lamblia (9.0%)

B. hominis (moderate to many) (8.9%)

G. lamblia (6%)

D. fragilis (3%)

N/A

Similar StudiesState

(author)

Texas

(current study)

California

(Garg et al.)

Illinois

(Peterson et al.)

Area of Origin

Helminths: East Asia (18.3%)

Protozoa: Latin America (70.8%)

Helminths: South Central Asia (10.8%)

Protozoa: Middle East (12.9%)

Overall: Middle East (56.5%)

Southeast Asia (48.9%)

Africa (48.9%)

Gender Helminths: males

Protozoa: females

Both: males

Helminths: no association

Protozoa: males (p=0.14)

N/A

Age Helminths: 717

Protozoa: 1834

Both: 717

Helminths: no association

Protozoa: under age 18 (p=0.01)

N/A

Statistically Significant Differences

Gender Males:

• Helminths (p≤0.01) • Both helminths and protozoa (p≤0.01)

Females:• Protozoa (p≤0.025)

Age 7 to 17 years:

• Helminths (p≤0.001)• Both helminths and protozoa (p≤0.001)

18 to 34 years:• Protozoa (p≤0.001)

Limitations

Significant portion of refugee database missing information (e.g. country of origin)

Number of specimens not equal to total number of refugees who entered Texas during study period

Country of origin may not be country where infection acquired

Only reflects data from refugees tested

Study Impact

Medical clinics across Texas Refugees General population

http://ww

w.am

s.usda.gov/cotton/OfficeP

ages/CO

%20im

ages/texas.jpg

Future studies

Demographic data: ensure that all possible data is gathered from every submission clinic

Multiple infections: analyze by specific organisms

Transit history: determine more accurate transit history for sample of refugees

http://www.humanrightsfirst.org/images/refugees/intl_refs/intl_ref_1.jpg

Acknowledgements

Mr. Jeff Taylor Ms. Katherine Von Alt Dr. Leanne Field Ms. Cathy Snider Mr. Stephen Murchison Mr. Sam Householder Ms. Nancy Elder Ms. Sandra Cranek Mr. Jim Schuermann Everyone in TDSHS Infectious

Disease Control Unit

Questions?