Pretravel Health Preparation Among US Residents Traveling to India to VFRs: Importance of Ethnicity in Defining VFRs

Henry C. Baggett MD, MPH, Susan Graham MSPH, Phyllis E. Kozarsky MD, Nancy Gallagher BA, Sena Blumensaadt BA, John Bateman BA, Paul J. Edelson MD, Paul M. Arguin MD, Stefanie Steele RN, MPH, Michelle Russell MPH, Christie Reed MD, MPH
DOI: http://dx.doi.org/10.1111/j.1708-8305.2008.00284.x 112-118 First published online: 1 March 2009

Abstract

Background International travelers visiting friends and relatives (VFRs) in lower income countries experience high rates of travel‐related infections. We examined demographic characteristics and pretravel preparation practices among US residents traveling to India to determine factors that may contribute to higher infection rates and that would allow for improved prevention strategies.

Methods A cross‐sectional study was conducted among US residents traveling to India in departure areas for flights to India at three US international airports during August 2005. Eligible travelers were US residents going to India who were English speaking and ≥18 years. Self‐administered questionnaires were used to assess knowledge of and compliance with pretravel health recommendations.

Results Of 1,574 eligible travelers, 1,302 (83%) participated; 60% were male and the median age was 37. Eighty‐five percent were of South Asian/Indian ethnicity and 76% reported VFR as the primary reason for travel. More than 90% of VFRs had at least a college education and only 6% cited financial barriers as reasons for not obtaining travel health services. VFRs were less likely than non‐VFR travelers to seek pretravel health advice, to be protected against hepatitis A or typhoid fever, and less likely to be taking appropriate antimalarial chemoprophylaxis. However, when stratified by ethnicity, travelers of South Asian ethnicity were less likely than other travelers to adhere to pretravel health recommendations, regardless of VFR status.

Conclusions Similar to previous studies, VFR status was associated with pretravel health practices that leave travelers at risk for important infectious diseases. This association differed by ethnicity, which may also be an important marker of nonadherence to pretravel health recommendations. These findings have important implications for identifying at‐risk travelers and properly targeting prevention messages.

An increasing proportion of preventable infectious diseases in the United States, such as hepatitis A, 1 measles, 2 typhoid fever, 3 and malaria, 4 is attributable to international travel. For instance, 74% of typhoid fever cases reported in the United States during 1999 to 2003 were related to international travel. 3 In addition to the morbidity of these infections, a single case of imported infection can have substantial public health impact related to secondary cases and resources required for investigation. 5

US residents traveling to low‐ or middle‐income countries increasingly report visiting friends and relatives (VFR) as the reason for travel. 6 Foreign‐born US residents comprised approximately 12% (34.2 million persons) of the 2004 population. 7 Travel to India among US residents increased nearly 150% from 1994 (254,000 travelers) to 2004 (629,000 travelers) and more than 55% listed VFR as their primary reason for travel. 8 Thus, more travelers are at risk for illnesses commonly acquired in India, such as typhoid fever and malaria.

VFR travelers have consistently been found to experience high rates of travel‐related infectious diseases and, compared to non‐VFR travelers, to be at increased risk for infections, such as hepatitis A, typhoid fever, 3 and malaria, 4,9,10 possibly due to a low use of travel health preventive services. Reasons previously cited for not using pretravel health services include financial limitations, language barriers, and a lower perceived risk of travel‐related infections among VFR travelers and their physicians. 6 However, few studies have evaluated barriers to pretravel preventive services or other cofactors that might explain the differences in travel health preparation among VFR travelers.

Improved understanding is needed of demographic characteristics, travel patterns, and pretravel health preparation of VFR travelers, as well as how these characteristics and disease risks differ by country of origin. We conducted a cross‐sectional survey among US residents traveling to India to assess their knowledge and practices regarding pretravel health recommendations and compared practices of VFR and non‐VFR travelers.

Methods

Setting and Participants

For 14 consecutive days during August 2005, we distributed questionnaires to eligible passengers traveling on a single Indian airline at each of three US airports: Chicago O’Hare, Newark Liberty, and John F. Kennedy in New York City. We approached all passengers in the departure areas before boarding to assess eligibility. Passengers were eligible if they were at least 18 years, spoke English, had a final destination of India, and lived in the United States. This study was determined to be exempt from a full institutional review board review by the US Centers for Disease Control and Prevention (CDC) human research protection office. Verbal consent was obtained from all participants.

Participants were asked to complete a 49‐question self‐administered survey. Information was collected anonymously on demographics, reasons for travel, and travel itineraries. Participants were asked about their pretravel health practices including visiting a health care professional and receiving vaccinations or medications to prevent hepatitis A, typhoid fever, and malaria.

Study Outcomes and Definitions

We compared demographic and travel characteristics of VFR and non‐VFR travelers. We assessed characteristics potentially associated with four main study outcomes: seeking pretravel advice, protection against hepatitis A and typhoid fever, and planned use of appropriate antimalarial chemoprophylaxis. Ethnicity, an important covariate in our analysis, was defined based on the participant’s response to the multiple‐choice question, “Which ethnic group best describes you?”, which included the choice: “Indian or South Asian.”

VFR travelers were defined as those reporting that the primary purpose for their trip was to visit friends or relatives; all others were non‐VFR travelers. Pretravel health advice was defined as visiting a health care professional in preparation for the trip. Hepatitis A protection was defined as ever having a history of hepatitis A infection or having received hepatitis A vaccine or immune globulin (IG). Participants were considered protected against typhoid fever if they reported having an up‐to‐date typhoid vaccine (ie, oral vaccine within 5 y or injectable vaccine within 2 y of travel). Appropriate medications for malaria chemoprophylaxis were mefloquine, atovaquone–proguanil, or doxycycline, as recommended by the US CDC for travelers to India. 11 The CDC also supports primaquine for primary prophylaxis in certain circumstances, but no participants reported using this medication.

Statistical Analysis

Categorical comparisons were analyzed by the chi‐square test and presented as prevalence ratios (PR). Continuous variables were compared by Student’s t‐test. Participants with missing data for individual comparisons were excluded from the relevant analyses. Multivariate logistic regression models were fit to estimate the adjusted prevalence odds ratios (POR) and 95% confidence intervals (CI) for each outcome after assessing for potential effect modifiers and confounders. Effect modification was considered present if the relationship between the exposure and the outcome differed meaningfully for different levels of the effect modifier. All variables with a p value ≤0.1 in univariate analysis along with age and sex were considered in the multivariate models. The criterion for keeping a covariate in the regression model was a >10% change in the POR after adjustment for the covariate. Statistical significance was defined as a p value ≤0.05. Analyses were performed by using STATA 8 (Stata Corp., College Station, TX, USA) and SAS 9.1.3 (SAS institute, Cary, NC, USA).

Results

We approached 1,574 eligible passengers, of whom 1,302 (83%) completed at least part of the survey. Participants had a median age of 37 years, 60% were male, and 91% had at least a college education (Table 1). The majority (85%) described themselves as being of “Indian or South Asian” ethnicity (hereafter referred to as South Asian). Seventy‐five percent listed their primary reason for travel as VFR and only 34% of all participants sought pretravel health advice. The most common reasons for not seeking pretravel health advice were a lack of awareness that advice was needed (59%) and the belief that vaccinations and medications were current (32%).

View this table:
Table 1

Characteristics of US residents traveling to India—August 2005 (N= 1,302)

n%*
Median age (y)37
 Interquartile range29–49
 Missing83
Male sex74959.7
 Missing47
Education
 Primary70.6
 Secondary997.9
 College/graduate school1,14891.5
 Missing48
Ethnicity
 Indian/South Asian1,06385.2
 White, non‐Hispanic14611.7
 Other Asian/Pacific Islander141.1
 Other 241.9
 Missing55
Citizenship
 United States62050.1
 India59748.2
 Other211.7
 Missing64
Previously traveled outside United States1,15990.2
 Missing17
Median trip duration (d)21
 Interquartile range4–30
 Missing97
Reasons for trip (>1 choice allowed)
 Visiting friends and relatives1,07883.6
 Vacation/tourism44534.5
 Business/convention1209.3
 Study/research574.4
 Missionary251.9
 Medical care/procedure141.1
 Volunteer work191.5
 Other574.4
 Missing12
Primary reason for trip
 Visiting friends and relatives97576.1
 Vacation/tourism1229.5
 Business/convention705.5
 Study/research372.9
 Missionary201.6
 Medical care/procedure80.6
 Volunteer work70.5
 Other423.3
 Missing21
≥1 Trip to India in previous 5 y94473.8
 Missing24
Obtained pretravel health advice  from health care professional43834.4
 Missing27
Obtained pretravel health advice from  travel medicine specialist (among those  who obtained pretravel advice)9221.8
 Missing15
Reasons for not obtaining pretravel health advice  [>1 choice allowed (N= 777)]
 Did not think needed/never considered45558.5
 Vaccinations and meds up to date24531.5
 Time limitations10012.9
 Did not know of facility to visit182.3
 No money/inadequate health insurance577.3
 Other628
 Missing60
Aware of travel recommendations from  (>1 choice allowed)
 Centers for Disease Control and Prevention45638.5
 World Health Organization28323.8
 Other695.8
 None55046.4
 Missing117
  • * Percentage of participants with available data.

  • Other ethnicities include black non‐Hispanic and Hispanic.

VFR Versus Non‐VFR Travelers

US VFR travelers (VFRs) traveling to India were similar to non‐VFRs in age and sex but differed in other demographic and travel characteristics (Table 2). VFRs were more likely than non‐VFRs to be Indian citizens, ethnically South Asian, and to have at least a college education.

View this table:
Table 2

Demographic and travel characteristics of US residents traveling to India according to primary reason for travel: visiting friends and relatives (VFR) versus Non‐VFR—August 2005*

CharacteristicVFR,n(%),N= 975Non‐VFR,n(%),N= 306p
Mean age (y)39.7 (SE = 0.41)41.6 (SE = 0.98)0.08
Male sex560 (59.5)178 (60.0)0.95
Citizenship<0.001
 United States406 (44.0)199 (67.2)
 India504 (54.6)89 (30.1)
 Other13 (1.4)8 (2.7)
Ethnicity<0.001§
 Indian/South Asian894 (95.9)155 (52.4)
 White, non‐Hispanic19 (2.0)124 (41.9)
 Other‡19 (2.0)17 (5.7)
Completed college education or higher872 (93.1)260 (87.3)0.003
Previously traveled outside United States878 (91.3)263 (86.8)0.03
Median planned trip duration (d) (interquartile range)21 (15–30)18 (13–60)0.2
Travel to India at least once in previous 5 y800 (82.0)146 (48.0)<0.0001
Obtained pretravel health advice from health care professional283 (29.8)147 (48.4)<0.001
Obtained pretravel health advice from travel medicine specialist  (among those who sought pretravel advice)38 (13.7)51 (37.0)<0.001
Reasons for not obtaining pretravel health advice(of 630)(of 146)
 Did not think needed/never considered367 (58.3)84 (57.5)0.87
 Vaccinations and meds up to date39 (6.2)16 (11.0)0.04
 Time limitations84 (13.3)17 (11.6)0.68
 No money/inadequate health insurance39 (6.2)16 (10.9)0.04
  • * Individual analyses include only participants with complete data.

  • US citizenship compared to Indian or other.

  • Other ethnicities include other Asian or Pacific Islander, black non‐Hispanic, Hispanic, and white non‐Hispanic.

  • § Indian/South Asian ethnicity compared to white, non‐Hispanic or other.

  • Kruskal–Wallis rank test.

VFR and Ethnicity

VFR status and ethnicity were strongly associated; 95% of VFRs were of South Asian ethnicity.Figure 1 demonstrates that differences in the disease protection outcomes by VFR status are minimal for South Asian travelers. Among non‐South Asian travelers, VFR status was still associated with lack of protection for two diseases (hepatitis A and malaria). Because ethnicity (South Asian vs Non‐South Asian) was judged to be an effect modifier for the association between VFR status and all four study outcomes, an interaction term with these variables was included in all multivariate models. In a secondary analysis, we defined VFRs as travelers who listed VFR as at least one reason for their trip (even if not the primary purpose), and our findings were similar for all four study outcomes.

Figure 1

Percentage of US residents traveling to India who were considered protected against hepatitis A infection, typhoid fever, and malaria (ie, planning to take chemoprophylaxis) according to VFR status and ethnicity—August 2005. Bars represent 95% confidence intervals. Hepatitis A protected: reported history of hepatitis A infection, hepatitis A vaccination, or immune globulin; typhoid fever protected: up‐to‐date typhoid vaccine (ie, oral vaccine in previous 5 y or injectable vaccine in previous 2 y); appropriate antimalarial chemoprophylaxis: mefloquine, atovaquone–proguanil, or doxycycline, as defined by Centers for Disease Control and Prevention recommendations for travelers to India. 11 Individual analyses include only participants with complete data. SA = South Asian ethnicity; VFR = primary reason for travel was to visit friends or relatives.

Pretravel Health Advice

In univariate analysis, VFRs were less likely than non‐VFRs to have sought pretravel health advice (Table 3). Seeking pretravel advice was also less common among travelers of South Asian ethnicity, males, age 18 to 39 years, non‐US citizens, persons who had traveled to India in the previous 5 years, and those with at least a college education.

View this table:
Table 3

Demographic and travel characteristics assessed as possible risk factors for four main study outcomes: pretravel health advice, protected against hepatitis A infection and typhoid fever, and taking appropriate antimalarial chemoprophylaxis—August 2005*

CharacteristicPretravel health adviceHepatitis A protectedTyphoid fever protected§Antimalarial chemoprophylaxis
VFR status
 VFR283 (29.8) 361 (50.9)51 (9.4)139 (16.3)
 Non‐VFR147 (48.4)181 (68.8)75 (36.6)108 (39.4)
 Prevalence ratio,p0.62, <0.0010.74, <0.0010.26, <0.0010.41, <0.001
Age (y)
 18–39201 (29.4)291 (57.7)70 (18.6)121 (19.1)
 ≥40210 (40.5)235 (53.4)56 (15.6)122 (26.0)
 Prevalence ratio,p0.73, <0.0011.08, 0.191.19, 0.330.73, 0.007
Sex
 Male211 (28.6)316 (54.7)53 (12.8)124 (18.1)
 Female215 (43.3)223 (57.2)75 (22.1)126 (28.4)
 Prevalence ratio,p0.66, <0.0010.96, 0.470.58, ≤0.0010.64, <0.001
Education level completed
 ≤High school46 (45.5)57 (65.5)18 (28.1)30 (32.3)
 ≥College381 (33.6)484 (54.9)110 (16.0)221 (21.3)
 Prevalence ratio,p1.35, 0.021.19, 0.071.76, 0.021.52, 0.02
Citizenship
 United States291 (47.6)323 (63.2)104 (25.5)191 (33.9)
 Indian (n= 597) or other (n= 21)127 (20.9)218 (48.3)22 (6.6)60 (10.6)
 Prevalence ratio,p2.28, <0.0011.31, <0.0013.89, <0.0013.20, <0.001
Ethnicity
 Indian/South Asian299 (28.6)399 (50.2)49 (8.0)149 (15.6)
 Non‐South Asian126 (69.6)140 (83.8)79 (57.7)102 (59.3)
 Prevalence ratio,p0.41, <0.0010.60, <0.0010.14, <0.0010.26, <0.001
Previously traveled outside United States
 Yes391 (34.3)490 (55.8)116 (17.0)224 (22.0)
 No43 (35.3)55 (56.7)12 (17.1)27 (23.5)
 Prevalence ratio,p0.97, 0.840.98, 0.911.00, 1.000.94, 0.72
Travel to India in previous 5 y
 Yes250 (27.0)360 (51.5)39 (7.5)118 (14.5)
 No179 (54.9)182 (67.4)88 (39.5)131 (42.1)
 Prevalence ratio,p0.49, <0.0010.76, <0.0010.19, <0.0010.34, <0.001
Trip duration (anticipated) (d)
 ≥21220 (33.7)250 (50.1)54 (14.0)119 (20.2)
 <21187 (35.4)275 (64.1)69 (20.9)120 (25.0)
 Prevalence ratio,p0.95, 0.540.78, <0.0010.67, 0.020.81, 0.07
  • Values given in parentheses show row percents. VFR = primary reason for travel was to visit friends or relatives.

  • * Individual analyses include only participants with complete data.

  • Pretravel advice: visited a health care professional in preparation for the current trip.

  • Hepatitis A protected: reported history of hepatitis A infection, hepatitis A vaccination, or immune globulin.

  • § Typhoid fever protected: up‐to‐date typhoid vaccine (ie, oral vaccine in previous 5 y or injectable vaccine in previous 2 y).

  • Appropriate antimalarial chemoprophylaxis: mefloquine, atovaquone–proguanil, or doxycycline, as defined by Centers for Disease Control and Prevention recommendations for travelers to India. 11

In logistic regression modeling, among non‐South Asian travelers, seeking pretravel health advice was significantly less common among VFRs compared to non‐VFRs (POR = 0.36, 95% CI: 0.16–0.79); however, among travelers of South Asian ethnicity, VFR status was not associated with seeking pretravel health advice. Seeking pretravel health advice remained significantly less common among males, travelers aged 18 to 39 years, non‐US citizens, and persons reporting travel to India in the previous 5 years.

Hepatitis A Protection

Previous hepatitis A infection was reported by a similar proportion of VFRs (8%) and non‐VFRs (7%). However, non‐VFRs were more likely than VFRs to have received hepatitis A vaccine or IG (66% vs 46%; PR = 0.71, 95% CI: 0.63–0.79). The most common reasons for not receiving vaccine or immunoglobulin did not differ between groups and included not being advised by their health care provider (36%), not being aware of the vaccine (18%), and believing that vaccine or IG was unnecessary (21%). In univariate analysis, 51% of VFRs were considered protected against hepatitis A infection compared to 69% of non‐VFRs (Table 3).

In logistic regression modeling, hepatitis A protection remained significantly associated with VFR status for travelers of non‐South Asian ethnicity (POR = 0.36, 95% CI: 0.14–0.96) but was not associated with VFR status for the South Asian ethnic group (Figure 1). Hepatitis A protection was also associated with US citizenship and travelers aged 18 to 39 years.

Typhoid Fever Protection

A past history of typhoid fever was reported by 13% of VFRs and 11% of non‐VFRs; prior typhoid vaccination was less common among VFRs (35%) than non‐VFRs (57%) (PR = 0.62, 95% CI: 0.54–0.72). Only 9% of VFRs compared with 37% of non‐VFRs met the criterion for up‐to‐date typhoid vaccination and were therefore considered protected (Table 3).

In logistic regression modeling, typhoid fever protection was no longer associated with VFR status for either South Asian or non‐South Asian travelers but was significantly less common among travelers who had been to India in the previous 5 years (POR = 0.35, 95% CI: 0.20–0.63).

Malaria Chemoprophylaxis

VFRs were more likely than non‐VFRs to report previous malaria infection (18% vs 11%; PR = 1.6, 95% CI: 1.2–2.3) and were less likely to believe that they were at risk for malaria during travel to India (20% vs 37%; PR = 0.54, 95% CI: 0.45–0.65). In univariate analysis, VFRs were less likely than non‐VFRs to be taking appropriate antimalarial chemoprophylaxis (Table 3).

In logistic regression, among non‐South Asian travelers, VFRs were less likely than non‐VFRs to be taking appropriate antimalarial chemoprophylaxis (POR = 0.46, 95% CI: 0.31–0.67); among travelers of South Asian ethnicity, taking chemoprophylaxis was not associated with VFR status (Figure 1). Taking chemoprophylaxis remained significantly more common among US citizens (POR = 2.71; 95% CI: 1.91‐3.85) and less common among those who had traveled to India in the previous 5 years (POR = 0.46; 95% CI: 0.31‐0.67).

Discussion

In this cross‐sectional survey of US residents traveling to India, we found that 65% of travelers had not sought pretravel health advice from a health care professional. In univariate analysis, VFRs were less likely than non‐VFRs to seek pretravel health advice and less likely to be protected against hepatitis A, typhoid fever, and malaria, but this association differed by ethnicity. Among travelers of South Asian ethnicity, VFRs did not differ from non‐VFRs in terms of seeking pretravel health advice or protection against travel‐related infections. Further, regardless of reason for travel, travelers of South Asian ethnicity were less likely than other travelers to follow pretravel health recommendations. Clinicians should be aware that persons of South Asian ethnicity traveling to India may be less likely to follow pretravel health recommendations, leaving them at risk for travel‐related infections.

Our findings counter some common beliefs about VFRs. Previous studies have speculated that financial barriers might limit access to pretravel health services for VFRs. While this may be true in some communities, more than 90% of VFRs in our study had at least a college education and only 6% cited financial barriers or lack of insurance as reasons for not obtaining travel health services (compared to 12% for non‐VFRs). Despite this high education level and adequate resources, only 34% of participants sought pretravel health advice and only 35% had ever received typhoid vaccination. More important reasons for not seeking pretravel health services were lack of awareness of recommendations and the belief that prevention measures were not needed. Our findings also suggest that health care providers may not be aware of recommendations (eg, 36% of travelers not vaccinated against hepatitis A reported that they were not advised to do so by their provider). Prevention efforts should focus on increasing awareness of the risk of travel‐related infections not only among travelers but also among clinicians.

Previous studies have concluded that VFRs are at increased risk for travel‐related infections. 3,4,9,12,13 This increased risk among VFRs has been attributed to infrequent use of travel health services, 7,9,13–16 poor adherence to pretravel preventive measures, 6,14,15 and more frequent high‐risk exposures during travel. 13 These conclusions have been based primarily on pretravel health surveys and qualitative assessments that did not separate VFR status from ethnicity. 17–21 Our findings support that among US travelers to India, pretravel health preparation does not differ by VFR status for travelers of South Asian ethnicity (ie, the majority ethnic group at their destination). When evaluating VFR as a risk factor for travel‐related infections, researchers should collect data necessary to evaluate different risk groups defined by the traveler’s ethnicity relative to the majority population of the destination.

A standard definition of VFR for use in epidemiologic studies does not exist. A recent study of ill travelers from the GeoSentinel Network demonstrated the importance of using a precise definition of VFR that accounts for the traveler’s country of birth. 13 They showed that, compared with tourist travelers, immigrant VFRs traveling back to their home countries were less likely to obtain pretravel health care and more likely to develop malaria and typhoid fever. Our findings support those of the GeoSentinel study in highlighting the importance of a clear VFR definition that accounts not only for the reason for travel but also for ethnicity or country of birth and travel destination.

Our study has some limitations. Our findings are not necessarily generalizable to US residents traveling to other low‐ or middle‐income countries. More than 90% of our participants were college educated. Travelers with less education or lower income may have limited access to pretravel health services and may have different health beliefs that influence their pretravel preparation. Enrolling travelers going to a single destination may also limit the generalizability of our findings. Our study design may be subject to selection bias because travelers who agreed to enroll may have differed from those who declined (eg, participants had to be able to read English). However, potential bias was limited by the high participation rate (83%) and the fact that only 5% of those who declined participation did so due to language barriers (data not shown). The cross‐sectional study design did not allow us to make inferences about causality, assess exposures during travel, or determine the incidence of travel‐related infections among our participants. We also had to rely on reported history of hepatitis A to determine potential susceptibility. Although some travelers may have had previously unrecognized hepatitis A infections, seroprevalence studies have demonstrated that a relatively high percentage of adult immigrants from developing countries remain susceptible to hepatitis A infection. 22–25

To better understand the risk factors for travel‐related infections, controlled studies are needed that include careful measures of pretravel health preparation, reason for travel, and potential exposures during travel. Although VFR status remains a marker for travel‐related infectious disease risks, in this study travelers of South Asian ethnicity had similarly poor adherence to pretravel health recommendations, regardless of reason for travel. These findings have important clinical and public health implications for identifying travelers at risk for travel infections and for targeting prevention messages to the most appropriate groups. Risk groups defined by ethnicity may be easier to identify than groups defined by reason for travel. Because most travelers never seek pretravel health advice, primary care clinicians should consider anticipatory pretravel counseling for their patients who are likely to travel to high‐risk areas.

Disclaimer

The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the CDC.

Declaration of interests

P.E.K. has accepted fee for chairing educational consultant from Berna Biotech/Crucell. All the other authors state that they have no conflicts of interest.

Acknowledgments

We are indebted to the US Quarantine Station staff in Chicago, New York, and Newark, for their support in survey implementation; Todd Mercer and Linda Quick for their contributions to study design and implementation; Nina Marano, Leisa Weld, and Brian Plikaytis for their thorough review and statistical support. This work was supported solely by the US CDC.

Footnotes

  • These findings were presented in part at the Northern European Conference on Travel Medicine, June 7 to 10, 2006, Glasgow, Scotland.

  • Address for US Mail:CDC/IEIP, Box 68, APO, AP 96546.

References

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