Diarrhoea during military deployment: current concepts and future directions

Extracellular components in enteroaggregative Escherichia coli biofilm and impact of treatment with proteinase K, DNase or sodium metaperiodate

Enteroaggregative E. coli (EAEC) is a major cause of diarrhea worldwide. EAEC are highly adherent to cultured epithelial cells and make biofilms. Both adherence and biofilm formation rely on the presence of aggregative adherence fimbriae (AAF). We compared biofilm formation from two EAEC strains of each of the five AAF types. We found that AAF type did not correlate with the level of biofilm produced. Because the composition of the EAEC biofilm has not been fully described, we stained EAEC biofilms to determine if they contained protein, carbohydrate glycoproteins, and/or eDNA and found that EAEC biofilms contained all three extracellular components. Next, we assessed the changes to the growing or mature EAEC biofilm mediated by treatment with proteinase K, DNase, or a carbohydrate cleavage agent to target the different components of the matrix. Growing biofilms treated with proteinase K had decreased biofilm staining for more than half of the strains tested. In contrast, although sodium metaperiodate only altered the biofilm in a quantitative way for two strains, images of biofilms treated with sodium metaperiodate showed that the EAEC were more spread out. Overall, we found variability in the response of the EAEC strains to the treatments, with no one treatment producing a biofilm change for all strains. Finally, once formed, mature EAEC biofilms were more resistant to treatment than biofilms grown in the presence of those same treatments.

Shigellosis in Southeast Asia: A systematic review and meta-analysis

BACKGROUND

Southeast Asia is attractive for tourism. Unfortunately, travelers to this region are at risk of becoming infected with Shigella. We conducted a meta-analysis to provide updates on Shigella prevalence in Southeast Asia, along with their serogroups and serotypes.

METHODS

We conducted a systematic search using PubMed, EMBASE, and Web of Science for peer-reviewed studies from 2000 to November 2022. We selected studies that detected Shigella in stools by culture or polymerase chain reaction (PCR). Two reviewers extracted the data using a standardized form and performed quality assessments using the Joanna Briggs Institute checklist. The random effects model was used to estimate the pooled prevalence of Shigella.

RESULTS

During our search, we identified 4376 studies. 29 studies (from six Southeast Asian countries) were included in the systematic review, 21 each in the meta-analysis of the prevalence of Shigella (Sample size: 109545) and the prevalence of Shigella serogroups. The pooled prevalence of Shigella was 4% (95% CI: 4-5%) among diarrhea cases. Shigella sonnei was the most abundant serogroup in Thailand (74%) and Vietnam (57%), whereas Shigella flexneri was dominant in Indonesia (72%) and Cambodia (71%). Shigella dysenteriae and Shigella boydii were uncommon (pooled prevalence of 1% each). The pooled prevalence of Shigella was 5% (95% CI: 4-6%) in children aged <5 years. The pooled prevalence showed a decreasing trend comparing data collected between 2000-2013 (5%; 95% CI: 4-6%) and between 2014-2022 (3%; 95% CI: 2-4%). Shigella prevalence was 6% in studies that included participants with mixed pathogens versus 3% in those without. Shigella flexneri serotype 2a was the most frequently isolated (33%), followed by 3a (21%), 1b (10%), 2b (3%), and 6 (3%).

CONCLUSIONS

This study provides compelling evidence for the development of effective Shigella vaccines for residents of endemic regions and travellers to these areas.

Antimicrobial resistance of enteric pathogens in the Military Health System, 2009 - 2019

BACKGROUND

Acute diarrhea (AD) can have significant impacts on military troop readiness. Medical providers must understand current trends of enteropathogen antimicrobial resistance (AMR) in service members (SMs) to inform proper, timely treatment options. However, little is known of enteric pathogen profiles across the Military Health System (MHS). The primary objectives of this study were to identify gaps in enteric pathogen surveillance within the MHS, describe the epidemiology of AMR in enteric pathogens, and identify trends across the MHS both within the Continental United States (CONUS) and outside of the Continental United States (OCONUS).

METHODS

Health Level 7 (HL7)-formatted laboratory data were queried for all specimens where Salmonella, Shigella, and Campylobacter species, as well as Shiga toxin-producing Escherichia coli (E. coli) (STEC) were isolated and certified between 1 January 2009 - 31 December 2019. Antibiotic susceptibility testing (AST) results were queried and summarized where available. Descriptive statistics were calculated for each organism by specimen source, year, and susceptibility testing availability.

RESULTS

Among a total of 13,852 enteric bacterial isolates, 11,877 (86%) were submitted from CONUS locations. Out of 1479 Shigella spp. and 6755 Salmonella spp. isolates, 1221 (83%) and 5019 (74%), respectively, reported any susceptibility results through the MHS. Overall, only 15% of STEC and 4% of Campylobacter spp. specimens had AST results available. Comparing AST reporting at CONUS versus OCONUS locations, AST was reported for 1175 (83%) and 46 (78%) of Shigella isolates at CONUS and OCONUS locations, respectively, and for 4591 (76%) and 428 (63%) of Salmonella isolates at CONUS and OCONUS locations, respectively.

CONCLUSIONS

This study revealed inconsistent enteropathogen AST conducted across the MHS, with differing trends between CONUS and OCONUS locations. Additional work is needed to assess pathogen-specific gaps in testing and reporting to develop optimal surveillance that supports the health of the force.

Supplemental Protein and a Multinutrient Beverage Speed Wound Healing after Acute Sleep Restriction in Healthy Adults

BACKGROUND

Physiologic and psychologic stress slow healing from experimental wounds by impairing immune function.

OBJECTIVES

We aimed to determine whether supplemental protein and multinutrient supplementation improved wound healing markers after acute stress induced by acute sleep restriction.

METHODS

In this single-blind, crossover study in generally healthy young adults (18 males/2 females; mean ± SD age: 19.7 ± 2.30 y), experimental wounds were created by removing the top layer of forearm blisters induced via suction after 48 h of 72-h sleep restriction (2-h nightly sleep), a protocol previously shown to delay wound healing. Skin barrier restoration (measured by transepidermal water loss) assessed wound healing ≤10 d postblistering, and local immune responses were evaluated by serial measurement of cytokine concentrations in fluid collected at wound sites for 48 h postblistering. Participants consumed controlled, isocaloric diets with either 0.900 g · kg-1 · d-1 protein plus placebo (PLA) or 1.50 g · kg-1 · d-1 protein plus multinutrient beverage [l-arginine: 20.0 g/d; l-glutamine: 30.0 g/d; omega-3 (n-3) fatty acids: 1.00 g/d; zinc sulfate: 24.0 mg/d; cholecalciferol: 800 IU/d; and vitamin C: 400 mg/d] (NUT) during sleep restriction and for 4 d afterwards.

RESULTS

Skin barrier restoration (primary outcome) was shorter for NUT (median: 3.98 d; IQR: 1.17 d) than for PLA (median: 5.25 d; IQR: 1.05 d) (P = 0.001). Cytokines from wound fluid (secondary outcome) increased over time (main effect of time P ≤ 0.001), except IL-13 (P = 0.07); however, no effects of treatment were observed.

CONCLUSIONS

Supplemental nutrition may promote wound healing after sleep restriction in healthy adults including military personnel, the latter of which also have a high incidence of wounds and infection.This trial was registered at clinicaltrials.gov as NCT03525184.

Exploring Changes in the Host Gut Microbiota During a Controlled Human Infection Model for Campylobacter jejuni

Campylobacter jejuni infection is a leading cause of foodborne disease, common to children, adult travelers, and military populations in low- to middle-income countries. In the absence of a licensed vaccine, efforts to evaluate prophylactic agents are underway. The prophylactic efficacy of a twice-daily, 550 mg dose of the antibiotic rifaximin demonstrated no efficacy against campylobacteriosis in a controlled human infection model (CHIM); however, samples from the CHIM study were utilized to assess how the human gut microbiome responds to C. jejuni infection, and if a ‘protective’ microbiota exists in study participants not developing campylobacteriosis. Statistically significant, but minor, differences in study participant beta diversity were identified during the challenge period (p = 0.002, R² = 0.042), but no significant differences were otherwise observed. Pre-challenge alpha diversity was elevated in study participants who did not develop campylobacteriosis compared to those who did (p < 0.001), but alpha diversity declined in all study participants from the pre-challenge period to post-discharge. Our work provides insight into gut microbiome shifts observed during a C. jejuni CHIM and following antibiotic treatment. This study utilized a high dose of 1.7 x 10⁵ colony-forming units of C. jejuni; future work could include CHIM studies performed with inocula more closely mimicking natural exposure as well as field studies involving naturally-occurring enteric infections.

A Multisite Network Assessment of the Epidemiology and Etiology of Acquired Diarrhea among U.S. Military and Western Travelers (Global Travelers' Diarrhea Study): A Principal Role of Norovirus among Travelers with Gastrointestinal Illness

U.S. military personnel must be ready to deploy to locations worldwide, including environments with heightened risk of infectious disease. Diarrheal illnesses continue to be among the most significant infectious disease threats to operational capability. To better prevent, detect, and respond to these threats and improve synchronization across the Department of Defense (DoD) overseas laboratory network, a multisite Global Travelers’ Diarrhea protocol was implemented with standardized case definitions and harmonized laboratory methods to identify enteric pathogens. Harmonized laboratory procedures for detection of Norovirus (NoV), enterotoxigenic Escherichia coli (ETEC), enteroaggregative E. coli, Shiga toxin–producing E. coli, enteropathogenic E. coli, Salmonella enterica, Shigella/enteroinvasive E. coli, and Campylobacter jejuni have been implemented at six DoD laboratories with surveillance sites in Egypt, Honduras, Peru, Nepal, Thailand, and Kenya. Samples from individuals traveling from wealthy to poorer countries were collected between June 2012 and May 2018, and of samples with all variables of interest available (n = 410), most participants enrolled were students (46%), tourists (26%), U.S. military personnel (13%), or other unspecified travelers (11%). One or more pathogens were detected in 59% of samples tested. Of samples tested, the most commonly detected pathogens were NoV (24%), ETEC (16%), and C. jejuni (14%), suggesting that NoV plays a larger role in travelers’ diarrhea than has previously been described. Harmonized data collection and methods will ensure identification and characterization of enteric pathogens are consistent across the DoD laboratory network, ultimately resulting in more comparable data for global assessments, preventive measures, and treatment recommendations.

Epidemiology and associated microbiota changes in deployed military personnel at high risk of traveler's diarrhea

Travelers’ diarrhea (TD) is the most prevalent illness encountered by deployed military personnel and has a major impact on military operations, from reduced job performance to lost duty days. Frequently, the etiology of TD is unknown and, with underreporting of cases, it is difficult to accurately assess its impact. An increasing number of ailments include an altered or aberrant gut microbiome. To better understand the relationships between long-term deployments and TD, we studied military personnel during two nine-month deployment cycles in 2015–2016 to Honduras. To collect data on the prevalence of diarrhea and impact on duty, a total of 1173 personnel completed questionnaires at the end of their deployment. 56.7% reported reduced performance and 21.1% reported lost duty days. We conducted a passive surveillance study of all cases of diarrhea reporting to the medical unit with 152 total cases and a similar pattern of etiology. Enteroaggregative E. coli (EAEC, 52/152), enterotoxigenic E. coli (ETEC, 50/152), and enteropathogenic E. coli (EPEC, 35/152) were the most prevalent pathogens detected. An active longitudinal surveillance of 67 subjects also identified diarrheagenic E. coli as the primary etiology (7/16 EPEC, 7/16 EAEC, and 6/16 ETEC). Eleven subjects were recruited into a nested longitudinal substudy to examine gut microbiome changes associated with deployment. A 16S rRNA amplicon survey of fecal samples showed differentially abundant baseline taxa for subjects who contracted TD versus those who did not, as well as detection of taxa positively associated with self-reported gastrointestinal distress. Disrupted microbiota was also qualitatively observable for weeks preceding and following the incidents of TD. These findings illustrate the complex etiology of diarrhea amongst military personnel in deployed settings and its impacts on job performance. Potential factors of resistance or susceptibility can provide a foundation for future clinical trials to evaluate prevention and treatment strategies.

Emerging Infectious Diseases and Antimicrobial Resistance (EIDAR)

Introduction

The Infectious Disease Clinical Research Program’s (IDCRP) Emerging Infectious Diseases and Antimicrobial Resistance (EIDAR) Research Area is a Department of Defense (DoD) clinical research capability that is responsive and adaptive to emerging infectious disease (EID) threats to US military readiness. Among active-duty and other Military Health System (MHS) beneficiaries, EIDAR research is largely focused on evaluating the incidence, risk factors, and acute- and long-term health effects of military-relevant EIDs, especially those caused by high-consequence pathogens or are responsible for outbreaks among US military populations. The EIDAR efforts also address Force Health Protection concerns associated with antimicrobial resistance and antimicrobial stewardship practices within the MHS.

Methods

The EIDAR studies utilize the approach of: (1) Preparing for emergent conditions to systematically collect clinical specimens and data and conduct clinical trials to assist the military with a scientifically appropriate response; and (2) Evaluating burden of emergent military-relevant infectious diseases and assessing risks for exposure and development of post-infectious complications and overall impact on military readiness.

Results

In response to the Ebola virus epidemic in West Africa, the IDCRP partnered with the National Institutes of Health in developing a multicenter, randomized safety and efficacy study of investigational therapeutics in Ebola patients. Subsequently, the EIDAR team developed a protocol to serve as a contingency plan (EpICC-EID) to allow clinical research activities to occur during future outbreaks of viral hemorrhagic fever and severe acute respiratory infections among MHS patients. The EIDAR portfolio recently expanded to include studies to understand exposure risks and impact on military readiness for a diversity of EIDs, such as seroincidence of non-Lyme disease borreliosis and Coccidioides fungal infections among high-risk military populations. The team also launched a new prospective study in response to the recent Zika epidemic to conduct surveillance for Zika and other related viruses among MHS beneficiaries in Puerto Rico. Another new study will prospectively follow U.S. Marines via an online health assessment survey to assess long-term health effects following the largest DoD Shiga Toxin-Producing Escherichia coli outbreak at the U.S. Marine Corps Recruit Depot-San Diego. In cooperation with the Trauma-Related Infections Research Area, the EIDAR Research Area is also involved with the Multidrug-Resistant and Virulent Organisms Trauma Infections Initiative, which is a collaborative effort across DoD laboratories to characterize bacterial and fungal isolates infecting combat-related extremity wounds and link lab findings to clinical outcomes. Furthermore, the EIDAR team has developed an Antimicrobial Resistance and Stewardship Collaborative Clinical Research Consortium, comprised of Infectious Disease and Pharmacy specialists.

Conclusions

The EIDAR Research Area is responsive to military-relevant infectious disease threats that are also frequently global public health concerns. Several new EIDAR efforts are underway that will provide Combatant Command Surgeons, Infectious Diseases Service Chiefs, and other Force Health Protection stakeholders with epidemiological information to mitigate the impact of EIDs and antimicrobial resistance on the health of U.S. military service members and their dependents.

Enteric etiological surveillance in acute diarrhea stool of United States Military Personnel on deployment in Thailand, 2013-2017

Background

Diarrhea remains a major public health problem for both civilian and military populations. This study describes the prevalence of acute diarrheal illness etiological agents, their antibiotic resistance distribution patterns, the resulting impact upon military force health protection, and potential prevention and treatment strategies.

Results

Forty-eight acute diarrhea stool samples from US military personnel deployed to Thailand from 2013–2017 were screened for enteric pathogens using ELISA, the TaqMan Array Card (TAC), and conventional microbiological methods. These isolates were also evaluated using antimicrobial susceptibility testing (AST) against ampicillin (AMP), azithromycin (AZM), ceftriaxone (CRO), ciprofloxacin (CIP), nalidixic acid (NA), erythromycin (ERY), and trimethoprim-sulfamethoxazole (SXT) using commercial methodology. Susceptibility results were interpreted following the CLSI and NARM guidelines. Questionnaire data obtained from 47/48 volunteers indicated that 89.4% (42/47) reported eating local food and the most common clinical symptoms were nausea and abdominal pain (51%; 24/47). Multiple bacterial species were identified from the 48 stool samples with diarrhea etiological agents being detected in 79% (38/48) of the samples distributed as follows: 43.8% (21/48) Campylobacter jejuni and Campylobacter species, 42% (20/48) diarrheagenic Escherichia coli, and 23% (11/48) Salmonella. Co-infections were detected in 46% (22/48) of the samples. All C. jejuni isolates were resistant to CIP and NA. One C. jejuni isolate exhibited resistance to both AZM and ERY. Lastly, an association between exposure to poultry and subsequent detection of the diarrhea-associated pathogens E. coli and P. shigelloides was significant (p < 0.05).

Conclusion

The detection of Campylobacter isolates with CIP, AZM and ERY resistance has critical force health protection and public health implications, as these data should guide effective Campylobacteriosis treatment options for deployed military members and travelers to Southeast Asia. Additional research efforts are recommended to determine the association of pathogen co-infections and/or other contributing factors towards diarrheal disease in military and traveler populations. Ongoing surveillance and AST profiling of potential disease-causing bacteria is required for effective disease prevention efforts and treatment strategies.

Medical evacuations of members of the French armed forces for infectious diseases in foreign operations

OBJECTIVES

Medical evacuations from foreign settings are a major health and strategic problem for the armed forces. This work aimed to study the characteristics of French military evacuations due to infectious diseases.

PATIENTS AND METHODS

We performed a retrospective study based on the registers of the French operational military staff for health to assess the characteristics of the strategic medical evacuation of French armed forces members on missions abroad between January 1, 2011 and December 31, 2016.

RESULTS

Out of 4633 included cases, 301 medical evacuations (6.5%) were carried out due to infectious situations. More than half of patients were repatriated to surgical wards (162 patients, 54%), 108 patients (36%) to medical wards, 21 patients (7%) to intensive care units, six patients (2%) to an armed forces medical center, and four files (1%) were incomplete. Among infectious emergencies, malaria led to 30 evacuations (10%) including 11 to intensive care units and one death before evacuation. Infectious diseases requiring medical evacuation were most often mild and community-acquired. Most soldiers were evacuated without medical assistance.

CONCLUSIONS

Infectious diseases during missions and medical repatriations carried out for infectious reasons are important epidemiological indicators to monitor. They make it possible to adapt preventive measures, training, and diagnostic and therapeutic tools which can be made available to front-line military physicians.

An outbreak of Shigella boydii serotype 20 in January 2015 amongst United Kingdom healthcare workers involved in the Ebola response in Sierra Leone

In January 2015, Public Health England and the United Kingdom (UK) Ministry of Defence investigated cases of diarrhoea and fever in military personnel recently returned to the UK after supporting the response to the Ebola epidemic in Sierra Leone. Tests for Ebola virus infection were negative. PCR tests detected the ipaH gene in 10/12 faecal specimens, and Shigella boydii serotype 20 was isolated from 7 patients. A case control study was undertaken and analysed using multivariable logistic regression. Consumption of a coronation chicken lunch at the transit camp in Sierra Leone (SL) 24-48 h prior to departure for the UK was significantly associated with disease [adjusted odds ratio (OR) 28.15, 95 % CI: 1.87-422.65]. In the context of heightened concern during the Ebola epidemic, this outbreak highlights the importance of rapid and effective microbiological and epidemiological investigations to identify the aetiological agent in patients presenting with fever and diarrhoea.

Effects of Psychological, Environmental and Physical Stressors on the Gut Microbiota

Stress, a ubiquitous part of daily human life, has varied biological effects which are increasingly recognized as including modulation of commensal microorganisms residing in the gastrointestinal tract, the gut microbiota. In turn, the gut microbiota influences the host stress response and associated sequelae, thereby implicating the gut microbiota as an important mediator of host health. This narrative review aims to summarize evidence concerning the impact of psychological, environmental, and physical stressors on gut microbiota composition and function. The stressors reviewed include psychological stress, circadian disruption, sleep deprivation, environmental extremes (high altitude, heat, and cold), environmental pathogens, toxicants, pollutants, and noise, physical activity, and diet (nutrient composition and food restriction). Stressors were selected for their direct relevance to military personnel, a population that is commonly exposed to these stressors, often at extremes, and in combination. However, the selected stressors are also common, alone or in combination, in some civilian populations. Evidence from preclinical studies collectively indicates that the reviewed stressors alter the composition, function and metabolic activity of the gut microbiota, but that effects vary across stressors, and can include effects that may be beneficial or detrimental to host health. Translation of these findings to humans is largely lacking at present. This gap precludes concluding with certainty that transient or cumulative exposures to psychological, environmental, and physical stressors have any consistent, meaningful impact on the human gut microbiota. However, provocative preclinical evidence highlights a need for translational research aiming to elucidate the impact of stressors on the human gut microbiota, and how the gut microbiota can be manipulated, for example by using nutrition, to mitigate adverse stress responses.

Antimicrobial resistance profiles of Shigella dysenteriae isolated from travellers returning to the UK, 2004-2017

PURPOSE

Antimicrobial resistance (AMR) profiles of 754 strains of Shigella dysenteriae isolated between 2004 and 2017 from UK travellers reporting symptoms of gastrointestinal (GI) disease were reviewed to look for evidence of emerging AMR associated with travellers' diarrhoea.

METHODOLOGY

A travel history was provided for 72.7 % (548/754) of cases, of which 90.9 % (498/548) reported travel outside the UK within 7 days of onset of symptoms, and 9.1 % (50/498) reported no travel in that time frame. During the course of this study, whole genome sequencing (WGS) was implemented for GI disease surveillance, and we compared phenotypic AMR profiles with those derived from WGS data (n=133).Results/Key findings. The phenotypic and genotypic AMR results correlated well, with 90.1 % (121/133) isolates having concordant results to 10 classes of antimicrobials. Resistance to the first-line drugs commonly used in the treatment of shigellosis was observed throughout the study (ampicillin, 54.1%; chloramphenicol, 33.7 %; sulphonamides, 76.0 %; trimethoprim, 80.0%). Between 2004 and 2017, resistance to all classes of antimicrobials (except the phenicols) increased. The proportion of isolates exhibiting reduced susceptibility to ciprofloxacin increased from 3.8 % in 2004 to 75.7 % in 2017, and this was significantly associated with cases reporting travel to Asia compared to Africa (P<0.001). Of the 201 sequenced isolates, 3.0 % (20/201) had either blaCTX-M-15 or blaCMY-4.

CONCLUSIONS

Increasing MDR, along with resistance to the fluroquinolones and the third generation cephalosporins, in Shigella dysenteriae causing travellers' diarrhoea provides further evidence for the need to regulatethe use of antimicrobial agents and continuous monitoring of emerging AMR.

The current state and future direction of DoD gut microbiome research: a summary of the first DoD gut microbiome informational meeting

The gut microbiome is increasingly recognized as integral to human health, and is emerging as a mediator of human physical and cognitive performance. This has led to the recognition that US Department of Defense (DoD) research supporting a healthy and resilient gut microbiome will be critical to optimizing the health and performance of future Warfighters. To facilitate knowledge dissemination and collaboration, identify resource capabilities and gaps, and maximize the positive impact of gut microbiome research on the Warfighter, DoD partners in microbiome research participated in a 2-day informational meeting co-hosted by the Natick Soldier Research, Engineering and Development Center (NSRDEC) and the US Army Research Institute of Environmental Medicine (USARIEM) on 16–17 November 2015. Attendee presentations and discussions demonstrated that multiple DoD organizations are actively advancing gut microbiome research. Common areas of research included the influence of military-relevant stressors on interactions between the microbiome and Warfighter biology, manipulation of the microbiome to influence Warfighter health, and use of the microbiome as a biomarker of Warfighter health status. Although resources and capabilities are available, they vary across laboratories and it was determined that centralizing certain DoD capabilities could accelerate progress. More significantly, the meeting created a foundation for a coordinated gut microbiome and nutrition research program aligning key DoD partners in the area of microbiome research. This report details the presentations and discussions presented during the 1st DoD Gut Microbiome Informational Meeting.

Strategies to Improve Management of Acute Watery Diarrhea during a Military Deployment: A Cost Effectiveness Analysis

To inform policy and decision makers, a cost-effectiveness model was developed to predict the cost-effectiveness of implementing two hypothetical management strategies separately and concurrently on the mitigation of deployment-associated travelers’ diarrhea (TD) burden. The first management strategy aimed to increase the likelihood that a deployed service member with TD will seek medical care earlier in the disease course compared with current patterns; the second strategy aimed to optimize provider treatment practices through the implementation of a Department of Defense Clinical Practice Guideline. Outcome measures selected to compare management strategies were duty days lost averted (DDL-averted) and a cost effectiveness ratio (CER) of cost per DDL-averted (USD/DDL-averted). Increasing health care and by seeking it more often and earlier in the disease course as a stand-alone management strategy produced more DDL (worse) than the base case (up to 8,898 DDL-gained per year) at an increased cost to the Department of Defense (CER $193). Increasing provider use of an optimal evidence-based treatment algorithm through Clinical Practice Guidelines prevented 5,299 DDL per year with overall cost savings (CER −$74). A combination of both strategies produced the greatest gain in DDL-averted (6,887) with a modest cost increase (CER $118). The application of this model demonstrates that changes in TD management during deployment can be implemented to reduce DDL with likely favorable impacts on mission capability and individual health readiness. The hypothetical combination strategy evaluated prevents the most DDL compared with current practice and is associated with a modest cost increase.

Management of Acute Diarrheal Illness During Deployment: A Deployment Health Guideline and Expert Panel Report

BACKGROUND

Acute diarrheal illness during deployment causes significant morbidity and loss of duty days. Effective and timely treatment is needed to reduce individual, unit, and health system performance impacts.

METHODS

This critical appraisal of the literature, as part of the development of expert consensus guidelines, asked several key questions related to self-care and healthcare-seeking behavior, antibiotics for self-treatment of travelers' diarrhea, what antibiotics/regimens should be considered for treatment of acute watery diarrhea and febrile diarrhea and/or dysentery, and when and what laboratory diagnostics should be used to support management of deployment-related travelers' diarrhea. Studies of acute diarrhea management in military and other travelers were assessed for relevance and quality. On the basis of this critical appraisal, guideline recommendations were developed and graded by the Expert Panel using good standards in clinical guideline development methodology.

RESULTS

New definitions for defining the severity of diarrhea during deployment were established. A total of 13 graded recommendations on the topics of prophylaxis, therapy and diagnosis, and follow-up were developed. In addition, four non-graded consensus-based statements were adopted.

CONCLUSIONS

Successful management of acute diarrheal illness during deployment requires action at the provider, population, and commander levels. Strong evidence supports that single-dose antimicrobial therapy is effective in most cases of moderate to severe acute diarrheal illness during deployment. Further studies are needed to address gaps in available knowledge regarding optimal therapies for treatment, prevention, and laboratory testing of acute diarrheal illness.

Incidence, Etiology and Risk Factors for Travelers' Diarrhea during a Hospital Ship-Based Military Humanitarian Mission: Continuing Promise 2011

Travelers’ diarrhea (TD) is the most common ailment affecting travelers, including deployed U.S. military. Continuing Promise 2011 was a 5-month humanitarian assistance/disaster response (HA/DR) military and non-governmental organization training mission aboard the hospital ship USNS Comfort, which deployed to Central and South America and the Caribbean between April and September 2011. Enhanced TD surveillance was undertaken during this mission for public health purposes. Passive surveillance (clinic visits), active surveillance (self-reported questionnaires), and stool samples were collected weekly from shipboard personnel. Descriptive statistics and multivariate-logistic regression methods were used to estimate disease burden and risk factor identification. Two polymerase chain reaction methods on frozen stool were used for microbiological identification. TD was the primary complaint for all clinic visits (20%) and the leading cause of lost duties days due to bed rest confinement (62%), though underreported, as the active self-reported incidence was 3.5 times higher than the passive clinic-reported incidence. Vomiting (p = 0.002), feeling lightheaded or weak (p = 0.005), and being a food handler (p = 0.017) were associated with increased odds of lost duty days. Thirty-eight percent of self-reported cases reported some amount of performance impact. Based on the epidemiological curve, country of exercise and liberty appeared to be temporally associated with increased risk. From the weekly self-reported questionnaire risk factor analysis, eating off ship in the prior week was strongly associated (adjusted odds ratio [OR] 2.4, p<0.001). Consumption of seafood increased risk (aOR 1.7, p = 0.03), though consumption of ice appeared protective (aOR 0.3, p = 0.01). Etiology was bacterial (48%), with enterotoxigenic Escherichia coli as the predominant pathogen (35%). Norovirus was identified as a sole pathogen in 12%, though found as a copathogen in an additional 6%. Despite employment of current and targeted preventive interventions, ship-board HA/DR missions may experience a significant risk for TD among deployed US military personnel and potentially impact mission success.

Combination vaccines against diarrheal diseases

Diarrheal diseases remain a leading cause of global childhood mortality and morbidity. Several recent epidemiological studies highlight the rate of diarrheal diseases in different parts of the world and draw attention to the impact on childhood growth and survival. Despite the well-documented global burden of diarrheal diseases, currently there are no combination diarrheal vaccines, only licensed vaccines for rotavirus and cholera, and Salmonella typhi-based vaccines for typhoid fever. The recognition of the impact of diarrheal episodes on infant growth, as seen in resource-poor countries, has spurred action from governmental and non-governmental agencies to accelerate research toward affordable and effective vaccines against diarrheal diseases. Both travelers and children in endemic countries will benefit from a combination diarrheal vaccine, but it can be argued that the greater proportion of any positive impact will be on the public health status of the latter. The history of combination pediatric vaccines indicate that monovalent or single disease vaccines are typically licensed first prior to formulation in a combination vaccine, and that the combinations themselves undergo periodic revision in response to need for improvement in safety or potential for wider coverage of important pediatric pathogens. Nevertheless combination pediatric vaccines have proven to be an effective tool in limiting or eradicating communicable childhood diseases worldwide. The landscape of diarrheal vaccine candidates indicates that there now several in active development that offer options for potential testing of combinations to combat those bacterial and viral pathogens responsible for the heaviest disease burden—rotavirus, ETEC, Shigella, Campylobacter, V. cholera and Salmonella.

Health protection during the Ebola crisis: the Defence Medical Services approach

This paper is a narrative of the policies, procedures, mitigations and observations of the application of Force Health Protection measures applied by the Ministry of Defence (MOD) for the deployment of military personnel to West Africa as part of the UK contribution to the international response to the Ebola crisis from July 2014 to July 2015. The MOD divided the threat into three risk categories: risk from disease and non-battle injury, Ebola risk for non-clinical duties and Ebola risk for healthcare workers. Overall risk management was directed and monitored by the OP GRITROCK Force Health Protection Board. There were six cases of malaria, four outbreaks of gastrointestinal disease, two needlestick injuries in Ebola-facing healthcare workers, one MOD Ebola case and five non-needlestick, high-risk exposures. This experience reinforces the requirement for the Defence Medical Services to have a high level of organisational competence to advise on Force Health Protection for the MOD.

Gastrointestinal Infections in Deployed Forces in the Middle East Theater: An Historical 60 Year Perspective

Infectious diarrhea has been among the most common maladies of military deployments throughout time. The U.S. military experienced a significant burden from this disease in the middle eastern and north African campaigns of World War II (WWII). This article compares patterns of disease experienced in WWII with the recent military deployments to the same region for Operation Iraqi Freedom and Operation Enduring Freedom (OIF/OEF). Remarkable similarities in the prevalence and risk factors were noted, which belie the assumed improvements in prevention against these infections. In both campaigns, peaks of diarrhea occurred shortly after arrival of new personnel, which were seasonally associated and were linked to initial lapses in field sanitation and hygiene. It is important to reassess current strategies, especially, in light of emerging evidence of the chronic sequelae of these common infections to include a reemphasis on or reexamination of vaccine development, rapid field diagnostics, treatment algorithms, and antimicrobial prophylaxis.

Surveillance of Food- and Smear-Transmitted Pathogens in European Soldiers with Diarrhea on Deployment in the Tropics: Experience from the European Union Training Mission (EUTM) Mali

Introduction. Since 2013, European soldiers have been deployed on the European Union Training Mission (EUTM) in Mali. From the beginning, diarrhea has been among the most “urgent” concerns. Diarrhea surveillance based on deployable real-time PCR equipment was conducted between December 2013 and August 2014. Material and Methods. In total, 53 stool samples were obtained from 51 soldiers with acute diarrhea. Multiplex PCR panels comprised enteroinvasive bacteria, diarrhea-associated Escherichia coli (EPEC, ETEC, EAEC, and EIEC), enteropathogenic viruses, and protozoa. Noroviruses were characterized by sequencing. Cultural screening for Enterobacteriaceae with extended-spectrum beta-lactamases (ESBL) with subsequent repetitive sequence-based PCR (rep-PCR) typing was performed. Clinical information was assessed. Results. Positive PCR results for diarrhea-associated pathogens were detected in 43/53 samples, comprising EPEC (n = 21), ETEC (n = 19), EAEC (n = 15), Norovirus (n = 10), Shigella spp./EIEC (n = 6), Cryptosporidium parvum (n = 3), Giardia duodenalis (n = 2), Salmonella spp. (n = 1), Astrovirus (n = 1), Rotavirus (n = 1), and Sapovirus (n = 1). ESBL-positive Enterobacteriaceae were grown from 13 out of 48 samples. Simultaneous infections with several enteropathogenic agents were observed in 23 instances. Symptoms were mild to moderate. There were hints of autochthonous transmission. Conclusions. Multiplex real-time PCR proved to be suitable for diarrhea surveillance on deployment. Etiological attribution is challenging in cases of detection of multiple pathogens.

Bending the curve: force health protection during the insertion phase of the Ebola outbreak response

After >10 years of enduring operations in Iraq and Afghanistan, Defence Strategic Direction is returning to a contingency posture. As the first post-Afghanistan operation, in September 2014, a UK Joint Inter-Agency Task Force deployed to Sierra Leone in response to the Ebola virus disease (EVD) epidemic in West Africa. The aims were expanding treatment capacity, assisting with training and supporting host nation resilience. The insertion phase of this deployment created a unique set of challenges for force health protection. In addition to the considerable risk of tropical disease and trauma, deployed personnel faced the risks of working in an EVD epidemic. This report explores how deployed medical assets overcame the difficulties of mounting a short-notice contingent operation in a region of the world with inherent major climatic and health challenges.

Evaluation of hepatocyte growth factor as a local acute phase response marker in the bowel: the clinical impact of a rapid diagnostic test for immediate identification of acute bowel inflammation

BACKGROUND

There are no rapid tests that can distinguish contagious gastroenteritis, which requires isolation at its onset, from exacerbation of chronic inflammatory bowel disease (IBD) or bowel engagement in the course of systemic inflammatory response syndrome (SIRS). Hepatocyte growth factor (HGF) is an acute phase cytokine that is produced at the site of injury. It has high affinity to sulfated glycan, and this binding affinity is lost during chronic inflammation. The fecal pH strongly impacts the prognosis for severe bowel disease. We developed a strip test to evaluate HGF as a local acute phase response marker in the bowel. This test assessed the binding affinity of HGF to sulfated glycans in fecal samples and determined fecal pH as an indicator of illness severity.

METHODS

Fresh feces from patients with diarrhea (n=513) were collected and tested blindly, and information about patient illness course and outcome was collected. Patients were classified based on the focus of inflammation and the cause of the symptoms. Objectively verified diagnoses of infectious gastroenteritis (n=131) and IBD onset/exacerbation and bowel cancer (n=44) were used to estimate the performance of the test strip. ELISA was performed on 101 freeze-thawed feces samples to determine the fecal HGF levels.

RESULTS

The test rapidly distinguished infectious gastroenteritis from non-infectious inflammatory causes of diarrhea (sensitivity, 87.96%; specificity, 90.9%; positive predictive value, 96.6%; negative predictive value, 71.4%; accuracy, 89.1%). Fecal pH (p<0.0001) and mortality within 28days of sampling (p<0.04) was higher in patients with sepsis/SIRS and diarrhea. The concentration of HGF was higher in strip test-positive stool samples (p<0.01).

CONCLUSIONS

HGF is a good local acute phase response marker of acute bowel inflammation. Test-strip determination of the binding affinity of fecal HGF to sulfated glycan was a rapid, equipment-free way to assess patients with diarrhea and to guide the diagnostic and therapeutic approaches on admission.

Prevention of infectious diseases during military deployments: a review of the French armed forces strategy

Military personnel in operations have always paid a high toll to infections. In the 21st century some of these diseases still cause outbreaks with significant morbidity and impact on deployments. The new configuration of the French Armed Forces requires the permanent preparedness of deployable units. During deployments, soldiers are at least exposed to the infectious diseases that are observed in travellers, but with a potentially severe impact for the combatting strengths and a risk for cancelation or failure of the operational durability. The most common disabling infections during military deployments are faeco-oral transmitted diseases including diarrhoea. Preventing infectious diseases during deployments is of great concern and the French medical service has established a strategy based on different components; risk assessment and preparation, immunizations, protective measures and chemoprophylaxis, health education, health surveillance, outbreak investigations and medical tracking. In this review, the authors present the context of deployment of the French Armed Forces, the main health risks they are exposed to and develop the key points of the force health protection strategy, focused on infections related to military deployments.

Expatriates: special considerations in pretravel preparation

Expatriates comprise a diverse set of travelers who face unique medical, psychiatric, and non-health-related risks as a result of increased exposure to host country environment and associated lifestyle. Expatriates have an increased risk of developing malaria, gastrointestinal disorders, latent tuberculosis, vaccine-preventable infections, and psychological disorders, when compared with other travelers, yet the majority of existing pretravel guidelines have been designed to suit the needs of nonexpatriates. Although greater interest in expatriate health issues has led to improved characterization of illness in this population, expatriate-specific risk mitigation strategies-including modifications to chemoprophylaxis recommendations, limiting tuberculosis exposure, and prevention of occupational or sexual blood-borne virus transmission-are poorly described. Occupations and destinations affect travel-related disease risk and should inform the pretravel consultation.