Tuberculosis in United States-Bound Follow-to-Join Asylees, 2014-2019

Persons may seek asylum in the United States or at a U.S. port of entry. Principal asylees are those who are granted asylum status. Their spouse and unmarried children under 21 years of age may be granted asylum if accompanying, or following to join, the principal asylees. U.S.-bound follow-to-join asylees must undergo an overseas medical examination that includes tuberculosis (TB) screening. Culture-based overseas TB screening in U.S.-bound follow-to-join asylees has not been evaluated. We evaluated data from overseas TB screening in 19,088 arrivals of follow-to-join asylees during 2014-2019 and assessed data from their postarrival evaluation, which is recommended for those at risk for TB. Of 19,088 arrivals of follow-to-join asylees, 29 (152 cases/100,000 persons) met criteria for class B0 TB (recent completion of TB treatment overseas) and 340 (1,781 cases/100,000 persons) met criteria for class B1 pulmonary TB (chest radiograph/clinical symptoms suggestive of TB but negative sputum cultures overseas). Of 6,847 persons aged 2 to 14 years from countries with a WHO-estimated TB incidence of ≥20 cases/100,000 population/year, 408 (6.0%) were classified as class B2 latent TB infection (LTBI). Postarrival evaluations were completed in 44.8%, 51.5%, and 40.4% of persons with class B0 TB, class B1 TB, and class B2 LTBI, respectively. In conclusion, culture-based overseas TB screening in U.S.-bound follow-to-join asylees is effective in identifying those with TB (class B0 TB) or those at risk for TB (class B1 TB and class B2 LTBI). Completion of postarrival evaluation for newly arrived follow-to-join asylees was less frequent than that reported for immigrants and refugees.

Diagnostic accuracy of three computer-aided detection systems for detecting pulmonary tuberculosis on chest radiography when used for screening: Analysis of an international, multicenter migrants screening study

The aim of this study was to independently evaluate the diagnostic accuracy of three artificial intelligence (AI)-based computer aided detection (CAD) systems for detecting pulmonary tuberculosis (TB) on global migrants screening chest x-ray (CXR) cases when compared against both microbiological and radiological reference standards (MRS and RadRS, respectively). Retrospective clinical data and CXR images were collected from the International Organization for Migration (IOM) pre-migration health assessment TB screening global database for US-bound migrants. A total of 2,812 participants were included in the dataset used for analysis against RadRS, of which 1,769 (62.9%) had accompanying microbiological test results and were included against MRS. All CXRs were interpreted by three CAD systems (CAD4TB v6, Lunit INSIGHT v4.9.0, and qXR v2) in offline setting, and re-interpreted by two expert radiologists in a blinded fashion. The performance was evaluated using receiver operating characteristics curve (ROC), estimates of sensitivity and specificity at different CAD thresholds against both microbiological and radiological reference standards (MRS and RadRS, respectively), and was compared with that of the expert radiologists. The area under the curve against MRS was highest for Lunit (0.85; 95% CI 0.83-0.87), followed by qXR (0.75; 95% CI 0.72-0.77) and then CAD4TB (0.71; 95% CI 0.68-0.73). At a set specificity of 70%, Lunit had the highest sensitivity (81.4%; 95% CI 77.9-84.6); at a set sensitivity of 90%, specificity was also highest for Lunit (54.5%; 95% CI 51.7-57.3). The CAD systems performed comparable to the sensitivity (98.3%), and except CAD4TB, to specificity (13.7%) of the expert radiologists. Similar trends were observed when using RadRS. Area under the curve against RadRS was highest for CAD4TB (0.87; 95% CI 0.86-0.89) and Lunit (0.87; 95% CI 0.85-0.88) followed by qXR (0.81; 95% CI 0.80-0.83). At a set specificity of 70%, CAD4TB had highest sensitivity (84.1%; 95% CI 82.3-85.8) followed by Lunit (80.9%; 95% CI 78.9-82.7); and at a set sensitivity of 90%, specificity was also highest for CAD4TB (54.6%; 95% CI 51.3-57.8). In conclusion, the study demonstrated that the three CAD systems had broadly similar diagnostic accuracy with regard to TB screening and comparable accuracy to an expert radiologist against MRS. Compared with different reference standards, Lunit performed better than both qXR and CAD4TB against MRS, and CAD4TB and Lunit better than qXR against RadRS. Moreover, the performance of the CADs can be impacted by characteristics of subgroup of population. The main limitation was that our study relied on retrospective data and MRS was not routinely done in individuals with a low suspicion of TB and a normal CXR. Our findings suggest that CAD systems could be a useful tool for TB screening programs in remote, high TB prevalent places where access to expert radiologists may be limited. However, further large-scale prospective studies are needed to address outstanding questions around the operational performance and technical requirements of the CAD systems.

US Postarrival Evaluation of Immigrant and Refugee Children with Latent Tuberculosis Infection Diagnosed Overseas, 2007-2019

OBJECTIVE

To assess outcomes from the US postarrival evaluation of newly arrived immigrant and refugee children aged 2-14 years who were diagnosed with latent tuberculosis infection (LTBI) during a required overseas medical examination.

STUDY DESIGN

We compared overseas and US interferon-γ release assay (IGRA)/tuberculin skin test (TST) results and LTBI diagnosis; assessed postarrival LTBI treatment initiation and completion; and evaluated the impact of switching from TST to IGRA to detect Mycobacterium tuberculosis infection overseas.

RESULTS

In total, 73 014 children were diagnosed with LTBI overseas and arrived in the US during 2007-2019. In the US, 45 939 (62.9%) completed, and 1985 (2.7%) initiated but did not complete a postarrival evaluation. Among these 47 924 children, 30 360 (63.4%) were retested for M tuberculosis infection. For 17 996 children with a positive overseas TST, 73.8% were negative when retested by IGRA. For 1051 children with a positive overseas IGRA, 58.0% were negative when retested by IGRA. Overall, among children who completed a postarrival evaluation, 18 544 (40.4%) were evaluated as having no evidence of TB infection, and 25 919 (56.4%) had their overseas LTBI diagnosis confirmed. Among the latter, 17 229 (66.5%) initiated and 9185 (35.4%) completed LTBI treatment.

CONCLUSIONS

Requiring IGRA testing overseas could more effectively identify children who will benefit from LTBI treatment. However, IGRA reversions may occur, highlighting the need for individualized assessment for risk of infection, progression, and poor outcome when making diagnostic and treatment decisions. Strategies are needed to increase the proportions receiving a postarrival evaluation and completing LTBI treatment.

Cross-Sectional Assessment of the Association of Eosinophilia with Intestinal Parasitic Infection in U.S.-Bound Refugees in Thailand: Prevalent, Age Dependent, but of Limited Clinical Utility

The most common causes of eosinophilia globally are helminth parasites. Refugees from high endemic areas are at increased risk of infection compared with the general U.S. population. It is widely accepted that eosinophilia is a good marker for helminth infection in this population, yet its absence has little predictive value for excluding infection. During an enhanced premigration health program, the CDC offered voluntary testing and management of intestinal parasites, among other conditions, to U.S.-bound refugees in Thailand. Stool specimens were tested for Ascaris lumbricoides, Strongyloides stercoralis, Trichuris trichiura, hookworms, Giardia lamblia, Cryptosporidium spp., and Entamoeba histolytica using quantitative polymerase chain reaction. Complete blood counts were performed to identify eosinophilia. Predictive values of eosinophilia for parasitic infections were calculated within nematode groups. Between July 9, 2012 and November 29, 2013, 2,004 participants were enrolled. About 73% were infected with at least one parasite. The overall median eosinophil count was 483 cells/μL (interquartile range [IQR] = 235-876 cells/μL). Compared with participants who did not test positive for any infection, higher eosinophil counts were observed in those infected with A. lumbricoides (RR = 1.3, 95% CI = 1.1-1.4), S. stercoralis (RR = 1.8, 95% CI = 1.4-2.4), Necator americanus (RR = 1.2, 95% CI = 1.1-1.4), and Ancylostoma ceylanicum (RR = 1.8, 95% CI = 1.5-2.2). Eosinophil counts were higher in younger participants (2-4 years versus 65+ years: RR = 4.2, 95% CI = 2.5-6.9), and lower in female participants (RR = 0.9, 95% CI = 0.8-0.9). Sensitivities ranged from 51% to 73%, specificities from 48% to 65%, and predictive values from 4% to 98%. The predictive value of eosinophilia is poor for the most common parasitic infections, and it should not be used alone for screening refugees.

Overseas Treatment of Latent Tuberculosis Infection in US–Bound Immigrants

Seventy percent of tuberculosis (TB) cases in the United States occur among non–US-born persons; cases usually result from reactivation of latent TB infection (LTBI) likely acquired before the person’s US arrival. We conducted a prospective study among US immigrant visa applicants undergoing the required overseas medical examination in Vietnam. Consenting applicants >15 years of age were offered an interferon-γ release assay (IGRA); those 12–14 years of age received an IGRA as part of the required examination. Eligible participants were offered LTBI treatment with 12 doses of weekly isoniazid and rifapentine. Of 5,311 immigrant visa applicants recruited, 2,438 (46%) consented to participate; 2,276 had an IGRA processed, and 484 (21%) tested positive. Among 452 participants eligible for treatment, 304 (67%) initiated treatment, and 268 (88%) completed treatment. We demonstrated that using the overseas medical examination to provide voluntary LTBI testing and treatment should be considered to advance US TB elimination efforts.

Disease Surveillance Among U.S.-Bound Immigrants and Refugees — Electronic Disease Notification System, United States, 2014–2019

Problem/Condition

Period Covered

Description of System

Results

Interpretation

Public Health Action

Prevalence of Overweight and Obesity in US-Bound Refugees: 2009-2017

Refugees are an often understudied population and vulnerable to poor health outcomes. No large-scale analyses have evaluated the prevalence of overweight and obesity in US-bound refugees. Using data obtained from the Centers for Disease Control (CDC) Electronic Disease Notification system, we quantified the prevalence of overweight and obesity in adult US-bound refugees by nationality from 2009 through 2017. This repeated cross-sectional analysis used CDC data to quantify and examine body mass index (BMI) trends in US-bound adult refugees during 2009-2017. Utilizing data from an overseas medical exam required for all US-bound refugees, we determined BMI for 334,746 refugees ≥ 18 years old who arrived in the United States during January 1, 2009-December 31, 2017. We calculated and compared the prevalence of overweight and obesity as well as changes in demographic characteristics (age, sex, and nationality) by year. Adjusted prevalence and prevalence ratios (APR) for yearly trends were assessed using a modified Poisson regression model with robust error variances. After adjusting for age, sex, and nationality, we observed a significant linear trend in the prevalence of overweight/obesity with an average annual relative percent increase of 3% for refugees entering the United States from 2009 through 2017 (APR = 1.031; 95% CI 1.029-1.033). The adjusted prevalence of overweight/obesity increased from 35.7% in 2009 to 44.7% in 2017. The prevalence of overweight and obesity in US-bound refugees increased steadily over the analysis period. Investigation into pre-migration and post-resettlement interventions is warranted.

The Effect of Drug Pricing on Outpatient Payments and Treatment for Three Soil-Transmitted Helminth Infections in the United States, 2010-2017

The price of certain antiparasitic drugs (e.g., albendazole and mebendazole) has dramatically increased since 2010. The effect of these rising prices on treatment costs and use of standard of care (SOC) drugs is unknown. To measure the impact of drug prices on overall outpatient cost and quality of care, we identified outpatient visits associated with ascariasis, hookworm, and trichuriasis infections from the 2010 to 2017 MarketScan Commercial Claims and Encounters and Multi-state Medicaid databases using Truven Health MarketScan Treatment Pathways. Evaluation was limited to members with continuous enrollment in non-capitated plans 30 days prior, and 90 days following, the first diagnosis. The utilization of SOC prescriptions was considered a marker for quality of care. The impact of drug price on the outpatient expenses was measured by comparing the changes in drug and nondrug outpatient payments per patient through Welch's two sample t-tests. The total outpatient payments per patient (drug and nondrug), for the three parasitic infections, increased between 2010 and 2017. The increase was driven primarily by prescription drug payments, which increased 20.6-137.0 times, as compared with nondrug outpatient payments, which increased 0.3-2.2 times. As prices of mebendazole and albendazole increased, a shift to alternative SOC and non-SOC drug utilization was observed. Using parasitic infection treatment as a model, increases in prescription drug prices can act as the primary driver of increasing outpatient care costs. Simultaneously, there was a shift to alternative SOC, but also to non-SOC drug treatment, suggesting a decrease in quality of care.

Prevalence of Malaria Parasite Infections among U.S.-Bound Congolese Refugees with and without Splenomegaly

All U.S.-bound refugees from sub-Saharan Africa receive presumptive antimalarial treatment before departing for the United States. Among U.S.-bound Congolese refugees, breakthrough malaria cases and persistent splenomegaly have been reported. In response, an enhanced malaria diagnostic program was instituted. Here, we report the prevalence of plasmodial infection among 803 U.S.-bound Congolese refugees who received enhanced diagnostics. Infections by either rapid diagnostic test (RDT) or PCR were detected in 187 (23%) refugees, with 78 (10%) by RDT only, 35 (4%) by PCR only, and 74 (9%) by both. Infections identified by PCR included 103 monoinfections (87 Plasmodium falciparum, eight Plasmodium ovale, seven Plasmodium vivax, and one Plasmodium malariae) and six mixed infections. Splenomegaly was associated with malaria detectable by RDT (odds ratio: 1.8, 95% CI: 1.0-3.0), but not by PCR. Splenomegaly was not strongly associated with parasitemia, indicating that active malaria parasitemia is not necessary for splenomegaly.

Health profile of adult special immigrant visa holders arriving from Iraq and Afghanistan to the United States, 2009-2017: A cross-sectional analysis

BACKGROUND

Between 2,000 and 19,000 Special Immigrant Visa (SIV) holders (SIVH) from Iraq and Afghanistan resettle in the United States annually. Despite the increase in SIV admissions to the US over recent years, little is known about the health conditions in SIV populations. We assessed the burden of select communicable and noncommunicable diseases (NCDs) in SIV adults to guide recommendations to clinicians in the US.

METHODS AND FINDINGS

We analyzed overseas medical exam data in Centers for Disease Control and Prevention's (CDC) Electronic Disease Notification system (EDN) for 19,167 SIV Iraqi and Afghan adults who resettled to the US from April 2009 through December 2017 in this cross-sectional analysis. We describe demographic characteristics, tuberculosis screening results, self-reported NCDs, and risk factors for NCDs (such as obesity and tobacco use). In our data set, most SIVH were male (Iraqi: 59.7%; Afghan: 54.7%) and aged 18-44 (Iraqi: 86.3%; Afghan: 95.6%). About 2.3% of Afghan SIVH and 1.1% of Iraqi SIVH had a tuberculosis condition. About 0.3% of all SIVH reported having chronic hepatitis. Among all SIVH, 56.5% were overweight or had obesity, 2.4% reported hypertension, 1.1% reported diabetes, and 19.4% reported current or previous tobacco use. Iraqi SIVH were 3.7 times more likely to have obesity (95% CI: 3.4-4.0), 2.5 times more likely to report diabetes (95% CI: 1.7-3.5), and 2.5 times more likely to be current or former smokers (95% CI: 2.3-2.7) than Afghan SIVH. Limitations include the inability to obtain all SIVH records, self-reported medical history of NCDs, and the underdiagnosis of NCDs such as hypertension and diabetes because formal laboratory testing for NCDs is not used during overseas medical exams.

CONCLUSION

In this analysis, we found that 56.5% of all SIVH were overweight or had obesity, 2.4% reported hypertension, 1.1% reported diabetes, and 19.4% reported current or previous tobacco use. In general, Iraqi SIVH were more likely to have obesity, diabetes, and be current or former smokers than Afghan SIVH. State public health agencies and clinicians doing domestic screening examinations of SIVH should consider screening for obesity-as per the CDC's Guidelines for the US Domestic Medical Examination for Newly Arriving Refugees-and smoking and, if appropriate, referral to weight management and smoking cessation services. US clinicians can consider screening for other NCDs at the domestic screening examination. Future studies can explore the health profile of SIV populations, including the prevalence of mental health conditions, after integration into the US.

Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practice

Background

Cholera is a major public health concern in displaced-person camps, which often contend with overcrowding and scarcity of resources. Maela, the largest and longest-standing refugee camp in Thailand, located along the Thai-Burmese border, experienced four cholera outbreaks between 2005 and 2010. In 2013, a cholera vaccine campaign was implemented in the camp. To assist in the evaluation of the campaign and planning for subsequent campaigns, we developed a mathematical model of cholera in Maela.

Methods

We formulated a Susceptible-Infectious-Water-Recovered-based transmission model and estimated parameters using incidence data from 2010. We next evaluated the reduction in cases conferred by several immunization strategies, varying timing, effectiveness, and resources (i.e., vaccine availability). After the vaccine campaign, we generated case forecasts for the next year, to inform on-the-ground decision-making regarding whether a booster campaign was needed.

Results

We found that preexposure vaccination can substantially reduce the risk of cholera even when <50% of the population is given the full two-dose series. Additionally, the preferred number of doses per person should be considered in the context of one vs. two dose effectiveness and vaccine availability. For reactive vaccination, a trade-off between timing and effectiveness was revealed, indicating that it may be beneficial to give one dose to more people rather than two doses to fewer people, given that a two-dose schedule would incur a delay in administration of the second dose. Forecasting using realistic coverage levels predicted that there was no need for a booster campaign in 2014 (consistent with our predictions, there was not a cholera epidemic in 2014).

Conclusions

Our analyses suggest that vaccination in conjunction with ongoing water sanitation and hygiene efforts provides an effective strategy for controlling cholera outbreaks in refugee camps. Effective preexposure vaccination depends on timing and effectiveness. If a camp is facing an outbreak, delayed distribution of vaccines can substantially alter the effectiveness of reactive vaccination, suggesting that quick distribution of vaccines may be more important than ensuring every individual receives both vaccine doses. Overall, this analysis illustrates how mathematical models can be applied in public health practice, to assist in evaluating alternative intervention strategies and inform decision-making.

Association of Diabetes and Tuberculosis Disease among US-Bound Adult Refugees, 2009-2014

Diabetes is associated with an increased risk for active tuberculosis (TB) disease. We conducted a case-control study and found a significant association between diabetes and TB disease among US-bound refugees. These findings underscore the value of collaborative management of both diseases.

Use of Oral Cholera Vaccine and Knowledge, Attitudes, and Practices Regarding Safe Water, Sanitation and Hygiene in a Long-Standing Refugee Camp, Thailand, 2012-2014

Oral cholera vaccines (OCVs) are relatively new public health interventions, and limited data exist on the potential impact of OCV use on traditional cholera prevention and control measures—safe water, sanitation and hygiene (WaSH). To assess OCV acceptability and knowledge, attitudes, and practices (KAPs) regarding cholera and WaSH, we conducted cross-sectional surveys, 1 month before (baseline) and 3 and 12 months after (first and second follow-up) a preemptive OCV campaign in Maela, a long-standing refugee camp on the Thailand-Burma border. We randomly selected households for the surveys, and administered questionnaires to female heads of households. In total, 271 (77%), 187 (81%), and 199 (85%) households were included in the baseline, first and second follow-up surveys, respectively. Anticipated OCV acceptability was 97% at baseline, and 91% and 85% of household members were reported to have received 1 and 2 OCV doses at first follow-up. Compared with baseline, statistically significant differences (95% Wald confidence interval not overlapping zero) were noted at first and second follow-up among the proportions of respondents who correctly identified two or more means of cholera prevention (62% versus 78% and 80%), reported boiling or treating drinking water (19% versus 44% and 69%), and washing hands with soap (66% versus 77% and 85%); a significant difference was also observed in the proportion of households with soap available at handwashing areas (84% versus 90% and 95%), consistent with reported behaviors. No significant difference was noted in the proportion of households testing positive for Escherichia coli in stored household drinking water at second follow-up (39% versus 49% and 34%). Overall, we observed some positive, and no negative changes in cholera- and WaSH-related KAPs after an OCV campaign in Maela refugee camp. OCV campaigns may provide opportunities to reinforce beneficial WaSH-related KAPs for comprehensive cholera prevention and control.

Safe water, sanitation, and hygiene (WaSH) are the primary measures for cholera prevention and control. Since 2010, oral cholera vaccines (OCVs) have been recommended as an additional tool for endemic and epidemic cholera prevention and control. Given the relatively new use of OCVs in public health programs, there is limited information on the impact of OCV use on traditional WaSH activities, i.e., can they serve as complementary tools, or will OCV use have a negative impact on WaSH-related behaviors? This study reports the findings of knowledge, attitudes and practices (KAP) surveys conducted before and after a preventive OCV campaign (2013) in a long-standing refugee camp in Thailand, where frequent cholera outbreaks had occurred in recent years. The surveys demonstrated high acceptability of the OCV campaign and several modest improvements in cholera and WaSH KAPs among the camp population. OCV campaigns may be used as opportunities to reinforce cholera and WaSH-related messaging towards strengthening comprehensive cholera prevention and control.

Mass vaccination with a two-dose oral cholera vaccine in a long-standing refugee camp, Thailand

BACKGROUND

During 2005-2012, surveillance in Maela refugee camp, Thailand, identified four cholera outbreaks, with rates up to 10.7 cases per 1000 refugees. In 2013, the Thailand Ministry of Public Health sponsored a two-dose oral cholera vaccine (OCV) campaign for the approximately 46,000 refugees living in Maela.

METHODS

We enumerated the target population (refugees living in Maela who are ≥1 year old and not pregnant) in a census three months before the campaign and issued barcoded OCV cards to each individual. We conducted the campaign using a fixed-post strategy during two eight-day rounds plus one two-day round for persons who had missed their second dose and recorded vaccine status for each individual. To identify factors associated with no vaccination (versus at least one dose) and those associated with adverse events following immunization (AEFI), we used separate marginal log-binomial regression models with robust variance estimates to account for household clustering.

RESULTS

A total of 63,057 OCV doses were administered to a target population of 43,485 refugees. An estimated 35,399 (81%) refugees received at least one dose and 27,658 (64%) received two doses. A total of 993 additional doses (1.5%) were wasted including 297 that were spat out. Only 0.05% of refugees, mostly children, could not be vaccinated due to repeated spitting. Characteristics associated with no vaccination (versus at least one dose) included age ≥15 years (versus 1-14 years), Karen ethnicity (versus any other ethnicity) and, only among adults 15-64 years old, male sex. Passive surveillance identified 84 refugees who experienced 108 AEFI including three serious but coincidental events. The most frequent AEFI were nausea (49%), dizziness (38%), and fever (30%). Overall, AEFI were more prevalent among young children and older adults.

CONCLUSIONS

Our results suggest that mass vaccination in refugee camps with a two-dose OCV is readily achievable and AEFI are few.

Airport exit and entry screening for Ebola--August-November 10, 2014

In response to the largest recognized Ebola virus disease epidemic now occurring in West Africa, the governments of affected countries, CDC, the World Health Organization (WHO), and other international organizations have collaborated to implement strategies to control spread of the virus. One strategy recommended by WHO calls for countries with Ebola transmission to screen all persons exiting the country for "unexplained febrile illness consistent with potential Ebola infection." Exit screening at points of departure is intended to reduce the likelihood of international spread of the virus. To initiate this strategy, CDC, WHO, and other global partners were invited by the ministries of health of Guinea, Liberia, and Sierra Leone to assist them in developing and implementing exit screening procedures. Since the program began in August 2014, an estimated 80,000 travelers, of whom approximately 12,000 were en route to the United States, have departed by air from the three countries with Ebola transmission. Procedures were implemented to deny boarding to ill travelers and persons who reported a high risk for exposure to Ebola; no international air traveler from these countries has been reported as symptomatic with Ebola during travel since these procedures were implemented.

Albendazole therapy and enteric parasites in United States-bound refugees

BACKGROUND

Beginning on May 1, 1999, the Centers for Disease Control and Prevention (CDC) recommended presumptive treatment of refugees for intestinal parasites with a single dose of albendazole (600 mg), administered overseas before departure for the United States.

METHODS

We conducted a retrospective cohort study involving 26,956 African and Southeast Asian refugees who were screened by means of microscopical examination of stool specimens for intestinal parasites on resettlement in Minnesota between 1993 and 2007. Adjusted prevalence ratios for intestinal nematodes, schistosoma species, giardia, and entamoeba were calculated among refugees who migrated before versus those who migrated after the CDC recommendation of presumptive predeparture albendazole treatment.

RESULTS

Among 4370 untreated refugees, 20.8% had at least one stool nematode, most commonly hookworm (in 9.2%). Among 22,586 albendazole-treated refugees, only 4.7% had one or more nematodes, most commonly trichuris (in 3.9%). After adjustment for sex, age, and region, albendazole-treated refugees were less likely than untreated refugees to have any nematodes (prevalence ratio, 0.19), ascaris (prevalence ratio, 0.06), hookworm (prevalence ratio, 0.07), or trichuris (prevalence ratio, 0.27) but were not less likely to have giardia or entamoeba. Schistosoma ova were identified exclusively among African refugees and were less prevalent among those treated with albendazole (prevalence ratio, 0.60). After implementation of the albendazole protocol, the most common pathogens among 17,011 African refugees were giardia (in 5.7%), trichuris (in 5.0%), and schistosoma (in 1.8%); among 5575 Southeast Asian refugees, only giardia remained highly prevalent (present in 17.2%). No serious adverse events associated with albendazole use were reported.

CONCLUSIONS

Presumptive albendazole therapy administered overseas before departure for the United States was associated with a decrease in the prevalence of intestinal nematodes among newly arrived African and Southeast Asian refugees.

Presumptive treatment to reduce imported malaria among refugees from east Africa resettling in the United States

During May 4, 2007-February 29, 2008, the United States resettled 6,159 refugees from Tanzania. Refugees received pre-departure antimalarial treatment with sulfadoxine-pyrimethamine (SP), partially supervised (three/six doses) artemether-lumefantrine (AL), or fully supervised AL. Thirty-nine malaria cases were detected. Disease incidence was 15.5/1,000 in the SP group and 3.2/1,000 in the partially supervised AL group (relative change = -79%, 95% confidence interval = -56% to -90%). Incidence was 1.3/1,000 refugees in the fully supervised AL group (relative change = -92% compared with SP group; 95% confidence interval = -66% to -98%). Among 39 cases, 28 (72%) were in refugees < 15 years of age. Time between arrival and symptom onset (median = 14 days, range = 3-46 days) did not differ by group. Thirty-two (82%) persons were hospitalized, 4 (10%) had severe manifestations, and 9 (27%) had parasitemias > 5% (range = < 0.1-18%). Pre-departure presumptive treatment with an effective drug is associated with decreased disease among refugees.

Non-pharmaceutical interventions during an outbreak of 2009 pandemic influenza A (H1N1) virus infection at a large public university, April-May 2009

Nonpharmaceutical interventions (NPIs), such as home isolation, social distancing, and infection control measures, are recommended by public health agencies as strategies to mitigate transmission during influenza pandemics. However, NPI implementation has rarely been studied in large populations. During an outbreak of 2009 Pandemic Influenza A (H1N1) virus infection at a large public university in April 2009, an online survey was conducted among students, faculty, and staff to assess knowledge of and adherence to university-recommended NPI. Although 3924 (65%) of 6049 student respondents and 1057 (74%) of 1401 faculty respondents reported increased use of self-protective NPI, such as hand washing, only 27 (6.4%) of 423 students and 5 (8.6%) of 58 faculty with acute respiratory infection (ARI) reported staying home while ill. Nearly one-half (46%) of student respondents, including 44.7% of those with ARI, attended social events. Results indicate a need for efforts to increase compliance with home isolation and social distancing measures.

Evaluation of universal antenatal screening for group B streptococcus

BACKGROUND

Group B streptococcal disease is one of the most common infections in the first week after birth. In 2002, national guidelines recommended universal late antenatal screening of pregnant women for colonization with group B streptococcus to identify candidates for intrapartum chemoprophylaxis.

METHODS

We evaluated the implementation of the guidelines in a multistate, retrospective cohort selected from the Active Bacterial Core surveillance, a 10-state, population-based system that monitors invasive group B streptococcal disease. We abstracted data from the labor and delivery records of a stratified random sample of live births and of all cases in which the newborn had early-onset group B streptococcal disease (i.e., disease in infants <7 days of age) in 2003 and 2004. We compared our results with those from a study with a similar design that evaluated screening practices in 1998 and 1999.

RESULTS

We abstracted records of 254 births in which the infant had group B streptococcal disease and 7437 births in which the infant did not. The rate of screening for group B streptococcus before delivery increased from 48.1% in 1998-1999 to 85.0% in 2003-2004; the percentage of infants exposed to intrapartum antibiotics increased from 26.8% to 31.7%. Chemoprophylaxis was administered in 87.0% of the women who were positive for group B streptococcus and who delivered at term, but in only 63.4% of women with unknown colonization status who delivered preterm. The overall incidence of early-onset group B streptococcal disease was 0.32 cases per 1000 live births. Preterm infants had a higher incidence of early-onset group B streptococcal disease than did term infants (0.73 vs. 0.26 cases per 1000 live births); however, 74.4% of the cases of group B streptococcal disease (189 of 254) occurred in term infants. Missed screening among mothers who delivered at term accounted for 34 of the 254 cases of group B streptococcal disease (13.4%). A total of 61.4% of the term infants with group B streptococcal disease were born to women who had tested negative for group B streptococcus before delivery.

CONCLUSIONS

Recommendations for universal screening were rapidly adopted. Improved management of preterm deliveries and improved collection, processing, and reporting of culture results may prevent additional cases of early-onset group B streptococcal disease.

Epidemiology of invasive group B streptococcal disease in the United States, 1999-2005

CONTEXT

Group B streptococcus is a leading infectious cause of morbidity in newborns and causes substantial disease in elderly individuals. Guidelines for prevention of perinatal disease through intrapartum chemoprophylaxis were revised in 2002. Candidate vaccines are under development.

OBJECTIVE

To describe disease trends among populations that might benefit from vaccination and among newborns during a period of evolving prevention strategies.

DESIGN AND SETTING

Analysis of active, population-based surveillance in 10 states participating in the Active Bacterial Core surveillance/Emerging Infections Program Network.

MAIN OUTCOME MEASURES

Age- and race-specific incidence of invasive group B streptococcal disease.

RESULTS

There were 14,573 cases of invasive group B streptococcal disease during 1999-2005, including 1348 deaths. The incidence of invasive group B streptococcal disease among infants from birth through 6 days decreased from 0.47 per 1000 live births in 1999-2001 to 0.34 per 1000 live births in 2003-2005 (P < .001), a relative reduction of 27% (95% confidence interval [CI], 16%-37%). Incidence remained stable among infants aged 7 through 89 days (mean, 0.34 per 1000 live births) and pregnant women (mean, 0.12 per 1000 live births). Among persons aged 15 through 64 years, disease incidence increased from 3.4 per 100,000 population in 1999 to 5.0 per 100,000 in 2005 (chi2(1) for trend, 57; P < .001), a relative increase of 48% (95% CI, 32%-65%). Among adults 65 years or older, incidence increased from 21.5 per 100,000 to 26.0 per 100,000 (chi2(1) for trend, 15; P < .001), a relative increase of 20% (95% CI, 8%-35%). All 4882 isolates tested were susceptible to penicillin, ampicillin, and vancomycin, but 32% and 15% were resistant to erythromycin and clindamycin, respectively. Serotypes Ia, Ib, II, III, and V accounted for 96% of neonatal cases and 88% of adult cases.

CONCLUSIONS

Among infants from birth through 6 days, the incidence of group B streptococcal disease was lower in 2003-2005 relative to 1999-2001. This reduction coincided with the release of revised disease prevention guidelines in 2002. However, the disease burden in adults is substantial and increased significantly during the study period.

Legionnaires' disease among residents of a long-term care facility: the sentinel event in a community outbreak

BACKGROUND

A long-term care facility (LTCF) reported an outbreak of Legionnaires' disease (LD) in September 2004.

METHODS

We conducted case finding through enhanced surveillance, medical record review (n = 131), and community surveys (n = 258). We cultured water samples from the LTCF and assayed their outdoor air-intake filters for Legionella DNA. We also investigated a cooling tower, the only nearby outdoor aerosol source.

RESULTS

Among 7 confirmed cases, 2 LTCF residents never exited, and 2 community residents never entered the LTCF during the incubation period. Among 63 water and biofilm samples collected from throughout the LTCF, we found no evidence of Legionella colonization, either in the potable water or air-handling systems. Conversely, we isolated a common outbreak-causing strain of Legionella pneumophila serogroup 1 from an industrial cooling tower located 0.4 km from the LTCF and recovered L pneumophila DNA from the LTCF's outdoor air-intake filters, suggesting that aerosolized Legionella from the cooling tower most likely entered the LTCF through the air-intake system or, possibly, through open windows.

CONCLUSION

Residents of LTCFs can acquire LD from community sources. A cluster of LD cases among LTCF residents does not necessarily indicate transmission from within the LTCF.

Fluid intake and decreased risk for hospitalization for dengue fever, Nicaragua

In a hospital and health center-based study in Nicaragua, fluid intake during the 24 hours before being seen by a clinician was statistically associated with decreased risk for hospitalization of dengue fever patients. Similar results were obtained for children <15 years of age and older adolescents and adults in independent analyses.

Predictors of chloroquine treatment failure in children and adults with falciparum malaria in Kampala, Uganda

Chloroquine-resistant falciparum malaria is a serious problem in much of sub-Saharan Africa. However, it is desirable to continue to use chloroquine as first-line therapy for uncomplicated malaria where it remains clinically effective. To identify predictors of chloroquine treatment failure, a 14-day clinical study of chloroquine resistance in patients with uncomplicated falciparum malaria was performed in Kampala, Uganda. Among the 258 patients (88% follow-up), 47% were clinical failures (early or late treatment failure) and 70% had parasitological resistance (RI-RIII). Using multivariate analysis, an age less than five (odds ratio [OR] = 3.4, 95% CI = 1.8-6.3) and a presenting temperature over 38.0 degreesC (OR = 2.0, 95% CI = 1.1-3.7) were independent predictors of treatment failure. In addition, patients who last took chloroquine 3 to 14 days prior to study entry were significantly more likely to be treatment failures compared to patients with very recent (less than 3 days) or no recent chloroquine use. In areas with significant chloroquine resistance, easily identifiable predictors of chloroquine treatment failure might be used to stratify patients into those for whom chloroquine use is acceptable and those for whom alternative treatment should be used.