ABSTRACTInternational travelers are frequently afflicted by acute infectious diarrhea, commonly referred to as travelers’ diarrhea (TD). Antibiotics are often prescribed as treatment or prophylaxis for TD; however, little is known about the impacts of these regimens on travelers’ gut microbiomes and carriage of antibiotic resistance genes (ARGs). Here, we analyzed two cohorts totaling 153 US and UK servicemembers deployed to Honduras or Kenya. These subjects either experienced TD during deployment and received a single dose of one of three antibiotics [Trial Evaluating Ambulatory Therapy of Travelers’ Diarrhea (TrEAT TD) cohort] or took once-daily rifaximin (RIF), twice-daily RIF, or placebo as prophylaxis to prevent TD [Trial Evaluating Chemoprophylaxis Against Travelers’ Diarrhea (PREVENT TD) cohort]. We applied metagenomic sequencing on 340 longitudinally collected stool samples and whole-genome sequencing on 54 Escherichia coli isolates. We found that gut microbiome taxonomic diversity remained stable across the length of study for most treatment groups, but twice-daily RIF prophylaxis significantly decreased microbiome richness post-travel. Similarly, ARG diversity and abundance were generally stable, with the exception of a significant increase for the twice-daily RIF prophylaxis group. We also did not identify significant differences between the ARG abundance of E. coli isolates from the TrEAT TD cohort collected from different treatment groups or timepoints. Overall, we found no significant worsening of gut microbiome diversity or an increase in ARG abundance following single-dose treatment for TD, underscoring that these can be effective with low risk of impact on the microbiome and resistome, and identified the relative microbiome risks and benefits associated with the three regimens for preventing TD.IMPORTANCEThe travelers’ gut microbiome is potentially assaulted by acute and chronic perturbations (e.g., diarrhea, antibiotic use, and different environments). Prior studies of the impact of travel and travelers’ diarrhea (TD) on the microbiome have not directly compared antibiotic regimens, and studies of different antibiotic regimens have not considered travelers’ microbiomes. This gap is important to be addressed as the use of antibiotics to treat or prevent TD—even in moderate to severe cases or in regions with high infectious disease burden—is controversial based on the concerns for unintended consequences to the gut microbiome and antimicrobial resistance (AMR) emergence. Our study addresses this by evaluating the impact of defined antibiotic regimens (single-dose treatment or daily prophylaxis) on the gut microbiome and resistomes of deployed servicemembers, using samples collected during clinical trials. Our findings indicate that the antibiotic treatment regimens that were studied generally do not lead to adverse effects on the gut microbiome and resistome and identify the relative risks associated with prophylaxis. These results can be used to inform therapeutic guidelines for the prevention and treatment of TD and make progress toward using microbiome information in personalized medical care.

Background: Travellers' diarrhoea (TD) is the most common travel-related illness with an estimated 10 million people afflicted annually. Outcome measures to assess the efficacy of primary and secondary TD interventions were historically based on diarrhoea frequency with >= 1 associated gastrointestinal symptom. Furthermore, efficacy determination is often made on the presence or absence of TD, rather than on TD illness severity. Current severity classifications are based on subjective consideration of impact of illness on activity. We sought to develop a standardized scoring system to characterize TD severity to potentially apply as a secondary outcome in future field studies. Methods: Data on multiple signs and symptoms were obtained from a previously published multisite TD treatment trial conducted by the US Department of Defense (TrEAT TD). Correlation, regression and multiple correspondence analyses were performed to assess impact on activity and a TD severity score was established. Results: Numerous signs and symptoms were associated with impaired function, with malaise and nausea most strongly associated [odds ratio (OR) 5.9-44.3, P < 0.0001 and OR 2.8-37.1, P < 0.0001, respectively). Based on co-varying symptomatology, a TD severity score accounting for diarrhoea frequency in addition to several signs and symptoms was a better predictor of negative impact on function than any single sign/symptom (chi(2) = 127.16, P <0.001). Additionally, there was a significant difference (P <0.0001) in the mean TD severity score between those with acute watery diarrhoea (3.9 +/- 1.9) and those with dysentery or acute febrile illness (6.2 +/- 2.0). Conclusions: The newly developed disease severity score better predicted a negative impact on activity due to TD than did any single sign or symptom. Incorporating multiple parameters into the TD severity score better captures illness severity and moves the field towards current recommendations for TD management by considering symptoms with high functional impact. Further validation of this score is needed in non-military travellers and other settings.

Background Travelers' diarrhea (TD) is common among military personnel deployed to tropical and subtropical regions. It remains unclear how TD and subsequent antibiotic treatment impact the resident microflora within the gut, especially given increased prevalence of antibiotic resistance among enteric pathogens and acquisition of multidrug-resistant organisms. We examined functional properties of the fecal microflora in response to TD, along with subsequent antibiotic treatment. Methods Fecal samples from US and UK military service members deployed to Djibouti, Kenya, and Honduras who presented with acute watery diarrhea were collected. A sample was collected at acute presentation to the clinic (day 0, before antibiotics), as well as 7 and/or 21 days following a single dose of antibiotics (azithromycin [500 mg], levofloxacin [500 mg], or rifaximin [1650 mg], all with loperamide). Each stool sample underwent culture and TaqMan reverse transcription polymerase chain reaction analyses for pathogen and antibiotic resistance gene detection. Purified DNA from each sample was analyzed using the HumiChip3.1 functional gene array. Results In total, 108 day 1 samples, 50 day 7 samples, and 94 day 21 samples were available for analysis from 119 subjects. Geographic location and disease severity were associated with distinct functional compositions of fecal samples. There were no overt functional differences between pre- and postantibiotic treatment samples, nor was there increased acquisition of antibiotic resistance determinants for any of the antibiotic regimens. Conclusions These results indicate that single-dose antibiotic regimens may not drastically alter the functional or antibiotic resistance composition of fecal microflora, which should inform clinical practice guidelines and antimicrobial stewardship. Clinical Trials Registration Number NCT01618591.

To discern if there was a particular genotype associated with clinical enteroaggregative Escherichia coli (EAEC) strains isolated from deployed military personnel (DMP) with travelers' diarrhea (TD), we characterized a collection of EAEC from DMP deployed to Afghanistan, Djibouti, Kenya, or Honduras. Although we did not identify a specific EAEC genotype associated with TD in DMP, we found that EAEC isolated at the first clinic visit were more likely to encode the dispersin gene aap than EAEC collected at follow-up visits. A majority of the EAEC isolates were typical EAEC that adhered to HEp-2 cells, formed biofilms, and harbored genes for aggregative adherence fimbriae (AAF), AggR, and serine protease autotransporters of Enterobacteriaceae (SPATEs). A separate subset of the EAEC had aggR and genes for SPATEs but encoded a gene highly homologous to that for CS22, a fimbriae more commonly found in enterotoxigenic E. coli. None of these CS22-encoding EAEC formed biofilms in vitro or adhered to HEp-2 cells. Whole genome sequence and single nucleotide polymorphism analyses demonstrated that most of the strains were genetically diverse, but that a few were closely related. Isolation of these related strains occurred within days to more than a year apart, a finding that suggests a persistent source and genomic stability. In an ampicillin-treated mouse model we found that an agg4A+ aar- isolate formed a biofilm in the intestine and caused reduced weight gain in mice, whereas a strain that did not form an in vivo biofilm caused no morbidity. Our diverse strain collection from DMP displays the heterogeneity of EAEC strains isolated from human patients, and our mouse model of infection indicated the genotype agg4A+ aar- and/or capacity to form biofilm in vivo may correlate to disease severity.

Travlers' diarrhea (TD) has historically been common among deployed military personnel and remains a leading infectious disease threat to this population. The risk factors, work performance, and illness associated with TD among British active duty service members exercising at British Army Training Unit Kenya (BATUK) were assessed. Members of the British Army who were finishing a 6-week combined arms training exercise in Nanyuki, Kenya, completed routine public health surveillance questionnaires. Survey data included information on demographics, rank, risk factors, illness characteristics, and impact on work performance. Among 1,227 survey respondents, 21.9% (n=269) reported having diarrhea, with an estimated 824 days of total missed work and 1,215 days of work underperformance. The majority of cases (54.6%) had multiple diarrheal episodes. One quarter (24.9%) of the respondents with TD sought medical care and 19.7% were bedded down because of their illness. There were no statistically significant differences between the TD and no TD groups on the demographic characteristics examined. The strongest risk factor for diarrhea was having a colleague with diarrhea (adjusted odds ratio=51.78; 95% confidence interval: 29.44-91.06). TD had a notable impact on duty status and operational capability. Efforts are needed to improve BATUK's participant education on the importance of diarrheal disease prevention and management.

Abstract Background Travelers’ diarrhea (TD) is a leading threat to military readiness. Most trials of rifaximin chemoprophylaxis involve civilians or short-duration travel, whereas military travelers are exposed for longer periods at austere locations and are often physically taxed. We sought to assess efficacy of two regimens among military personnel deployed overseas. Methods This was a multi-site, double-blind, placebo-controlled trial of deployed military, randomized to placebo, rifaximin 550 mg daily, or rifaximin 550 mg twice-daily, for up to 42 days (1:1:1; 6 randomizations/block). Diaries were reviewed with subjects on return. Primary endpoint was time to first unformed stool (TFUS) in a TD episode. Other endpoints were assessed by intention to treat (ITT) and subgroups included incidence of any loose stool, meeting criteria for TD, safety, efficacy, adherence and impact to activity endpoints. Results 343 subjects were included in the ITT population. All UK travelers deployed to a single-site in Kenya; US travelers mostly deployed to various Asia-Pacific locations. Of 73 (21.2%) subjects reporting diarrhea, 42 (57.5%) met TD criteria. Among rifaximin-treated subjects, 15.9% (n=17) reported diarrhea in the twice-daily arm, 20.7% (n=25) in the daily arm, vs. 27.0% (n=31) of placebo recipients; p=.04 and 0.26 respectively. TD was reported by 10.3% (n=11) and 10.7% (n=13) in the daily and twice-daily arms, vs. 15.7% (n=18) among placebo recipients; p=0.24 vs. 0.26 respectively. Among UK personnel, a twice-daily regimen vs. placebo resulted in significantly fewer TD episodes (1.6% vs. 11.9%; p=0.03). Adverse events were similar between groups. Table 1: Demographics, endpoints, and adverse events (Comparisons are across placebo vs. each dosing regimen. Intent-to-treat [ITT] population defined as subjects enrolled into the study, randomized, travelled and had follow-up. p-values calculated from chi-square or Fisher’s exact test [categorical variables] and Wilcoxon-Mann-Whitney test [continuous variables]. Analyses performed on SAS v9.4. BID: twice-daily) Conclusion This is the first trial comparing two high-dose regimens of rifaximin prophylaxis in deployed personnel. Unlike prior reports, neither regimen was associated with an overall significant decrease in TD, potentially due to low overall TD incidence. However, the twice-daily regimen was associated with a numerically lower incidence of diarrheal stool, and in the UK subject group, there was a significant decrease of both TD and diarrheal stool. The impact of variability in regional TD risk, pathogen distribution and adherence in austere deployment environments on efficacy will be reviewed. Disclosures All Authors: No reported disclosures

We evaluated stool enteropathogen detection by semiquantitative polymerase chain reaction (PCR) in 108 subjects with travelers' diarrhea before and 3 weeks after treatment. Stool samples from 21 subjects were positive for the same pathogen species at both visits. We discuss factors that should be considered when interpreting stool PCR data after treatment.

INTRODUCTION: Travelers’ diarrhea (TD) is a commonly diagnosed acute illness among those visiting tropical and sub-tropical regions with substantial consequences. While antibiotic treatment (with lopermaide) substantially reduces TD symptoms and duration, a growth in concerns about the off-target effects of TD treatment on the impact of resident microflora and the potential adverse effects associated with acquisition of multi-drug resistant organisms (MDRO). To date, most microbiome analyses have studied microbial structure/composition, while the functional capabilities of the gut microbiota remain largely unstudied. We set out to understand the functional properties of the gut microflora in response to TD acquired in diverse geographic regions, associations with different single-dose therapies, MDRO acquisition. METHODS: Fecal samples from USA & UK military service members in 3 continents that presented with acute watery TD were collected at acute presentation (day 1, prior to antibiotics), as well as 7 and/or 21 days following a single-dose of antibiotics (azithromycin (500 mg), levofloxacin (500 mg), or rifaximin (1650 mg) with loperamide). Each sample underwent culture and TaqMan RT-PCR analyses for pathogen detection and a limited set of ESBL-PE genetic probes. Purified DNA from each sample was analyzed using the HumiChip v2.0 microarray which contains over 150,000 DNA probes specific for genes involved in various functional processes including antibiotic resistance, virulence, stress responses, and nutrient metabolism. RESULTS: In total, 125 Day 1 samples, 64 Day 7 samples, and 105 Day 21 samples were available for analysis from 135 subjects. Ordination analysis revealed that subjects enrolled in each country had distinct functional profiles. While we did not observe overt differences in functional profiles between treatment groups, we observed an increase in functional diversity from day 1 to day 21 in the levofloxacin treatment group, relative to azithromycin and rifaximin groups. Additionally, we noted distinct geographical patterns of resistome patterns at baseline and post-illness, but lesser influence of antibiotic effects on post-treatment functional genomic composition. CONCLUSION: A thorough understanding of how antibiotics impact the functional properties of the gut microbiota will help inform future treatment options, antibiotic stewardship in TD patients, and the reduction of potential post-infective complications due to MDRO pathobionts.

One-hundred years have passed since the original description of the commonly described phenomenon of persistent abdominal symptoms being triggered by an acute enteric infection. This first account was generated out of astute observations by Sir Arthur Hurst in World War I. Additional descriptions followed from military and non-military practitioners adding the evidence which has transitioned this recognized condition from association to causation. While mechanistic understanding is an area of active pursuit, this historical accounting of a centuries progress highlights important advances and contributions of military medicine and scientists to advances benefiting global populations.

Background: Diarrhea is a well-established problem in travellers, with military personnel at especially high risk. This study aimed to characterise the spectrum of pathogens causing diarrhea in UK military personnel in South Sudan, and assess the utility of culture-independent testing for etiology and antimicrobial resistance in a logistically challenging and austere environment. Methods: All military personnel presenting with diarrhea were admitted to the UK Level 2 Medical Treatment Facility in Bentiu, South Sudan. Samples were tested for etiology utilising multiplex PCR-based diagnostics (BioFire FilmArray). In addition, the presence of carbapenemase resistance genes was determined using the geneXpert Carba-R platform. Results: Over 5 months, 127 samples were tested. The vast majority of pathogens detected were diarrheagenic Escherichia coli. The presence of either enterotoxigenic (ETEC) or enteropathogenic (EPEC) E. coli was a significant predictor of the other being present. In this study patients presenting with vomiting were 32 times more likely to have norovirus than not (p < 0.001). No carbapenem resistance was detected. Conclusions: Diarrhea in UK military personnel in South Sudan was determined to be predominantly bacterial, with norovirus presenting a distinct clinical and epidemiological pattern. Multiplex PCR and molecular resistance point of care testing were robust and effective in this environment.

The use of Polymerase Chain Reaction (PCR) assays for pathogen detection in travelers’ diarrhea (TD) field studies is limited by the on-site processing and storage requirements for fecal specimens. The objectives of this investigation were to i) characterize the pathogen distribution in deployed military personnel with TD using the TaqMan® Array Card PCR (TAC) on frozen stool and diarrheal smears on Whatman FTA Elute cards (FTA cards), and to ii) compare TAC detection of enteropathogen targets using smeared FTA cards and frozen stool, using TAC on frozen stool as the ‘reference standard’. Stool samples, obtained from active duty personnel with acute TD enrolled in a field trial, were smeared onto FTA cards and stored at room temperature. A corresponding aliquot of stool was frozen in a cryovial. FTA cards and frozen stool samples were tested at a central lab, using a customized TAC for detection of TD pathogens. 187 paired frozen stool samples and smeared FTA cards were stored for a median of 712 days (IQR 396–750) before testing. Overall detection rates were 78.6% for frozen stool and 73.2% for FTA cards. Diarrheagenic Escherichia coli were the most common bacteria identified. Using the TAC results on frozen stool as the reference, the overall sensitivity and specificity of TAC on FTA cards was 72.9% and 98.0% respectively. TAC on FTA cards demonstrated a decrease in sensitivity with increasing frozen stool quantification cycle (Cq) (90.0% in FTA cards with a corresponding frozen stool Cq < 30, and 72.9% in samples with a corresponding frozen stool Cq < 35). Our findings support the use and further development of FTA cards in combination with a quantitative PCR assay for enteropathogen detection in TD field studies.

Background Recommended treatment for travelers' diarrhea includes the combination of an antibiotic, usually a fluoroquinolone or azithromycin, and loperamide for rapid resolution of symptoms. However, adverse events, postdose nausea with high-dose azithromycin, effectiveness of single-dose rifaximin, and emerging resistance to front-line agents are evidence gaps underlying current recommendations. Methods A randomized, double-blind trial was conducted in 4 countries (Afghanistan, Djibouti, Kenya, and Honduras) between September 2012 and July 2015. US and UK service members with acute watery diarrhea were randomized and received single-dose azithromycin (500 mg; 106 persons), levofloxacin (500 mg; 111 persons), or rifaximin (1650 mg; 107 persons), in combination with loperamide (labeled dosing). The efficacy outcomes included clinical cure at 24 hours and time to last unformed stool. Results Clinical cure at 24 hours occurred in 81.4%, 78.3%, and 74.8% of the levofloxacin, azithromycin, and rifaximin arms, respectively. Compared with levofloxacin, azithromycin was not inferior (P = .01). Noninferiority could not be shown with rifaximin (P = .07). At 48 and 72 hours, efficacy among regimens was equivalent (approximately 91% at 48 and 96% at 72 hours). The median time to last unformed stool did not differ between treatment arms (azithromycin, 3.8 hours; levofloxacin, 6.4 hours; rifaximin, 5.6 hours). Treatment failures were uncommon (3.8%, 4.4%, and 1.9% in azithromycin, levofloxacin, and rifaximin arms, respectively) (P = .55). There were no differences between treatment arms with postdose nausea, vomiting, or other adverse events. Conclusions Single-dose azithromycin, levofloxacin, and rifaximin with loperamide were comparable for treatment of acute watery diarrhea. Clinical Trial Registration NCT01618591.

BACKGROUNDAcute 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.METHODSThis 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.RESULTSNew 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.CONCLUSIONSSuccessful 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.

Gogtay and Ferner raise important issues regarding the use of mefloquine for malaria chemoprophylaxis in British military personnel.1 However, we feel that some points need clarification. Although malaria has had a major impact on British Armed Forces in the past, the last operational death of a British service person from malaria occurred in …

Miriam Shuchman in her World Report (Dec 20, p e67)1Shuchman M Sierra Leone doctors call for better care for colleagues.Lancet. 2014; 384: e67Summary Full Text Full Text PDF PubMed Scopus (9) Google Scholar and the Lancet editorial (Dec 20, p 2174)2The LancetEbola: protection of health-care workers.Lancet. 2014; 384: 2174Scopus (3) Google Scholar raise the very important issue of the need for better care for doctors and other health-care workers putting their lives at risk managing Ebola in west Africa. However, some of the assertions and conclusions need to be balanced and indeed corrected. The UK Defence Medical Services (DMS) was tasked in August, 2014 to initially deploy for 60 days to support the UK Department for International Development (after a call by WHO) in provision of humanitarian assistance to the Sierra Leonean Government in its response to the Ebola crisis, recognising that long-term support would be provided by the non-governmental organisation community. A high-quality, mission-specific, intensive training package was developed in-house with external support, and the cohort of trained health-care workers (HCWs) deployed at the end of October, 2014. The UK DMS Ebola Treatment Facility (ETF) is a 20-bed facility specifically designed to care for HCWs, and the care delivered is the most advanced within west Africa, offering a level of care that includes use of ventricular ultrasound-guided fluid management, inotropic support, coagulopathy management with blood products, and intensive 1:1 nursing. Care is delivered (not just led) by UK consultants for every patient. Expert consensus is that haemodialysis and ventilator support are not likely to offer substantial benefit to severely ill patients with Ebola.3Jacobs M Beadsworth M Schmid M Tunbridge A Provision of care for Ebola.Lancet. 2014; 384: 2105-2106Summary Full Text Full Text PDF PubMed Scopus (11) Google Scholar The level of care delivered is reviewed every week by senior clinicians within the UK military, taking advice from national and international experts as evidence and experience develops. Since Nov 5, 2014, the unit has offered places to all HCWs referred, no matter where they work. 91% (24) of those admitted with Ebola were local nationals, 57% of whom were HCWs. Despite patients often declining to be admitted until late in their disease course, the case fatality rate is 45%, which is a substantial improvement on that elsewhere in country. The unit has undergone a planned expansion to ensure sufficient capacity for all HCWs in need. To link the junior doctors' strike with access to the UK DMS ETF is disappointing. The main reason for this strike was the death of three doctors in 3 days at the Connaught Hospital (Freetown, Sierra Leone) and a scarcity of equipment locally to manage patients in a safe way.4O'Carroll L Ebola crisis: Sierra Leone doctors go on strike over inadequate equipment.The Guardian. Dec 9, 2014; (accessed Dec 18, 2014).http://www.theguardian.com/world/2014/dec/09/ebola-crisis-sierra-leone-doctors-strike-inadequate-equipmentGoogle Scholar At the meeting between UK Government officials (including JJHT) and the Sierra Leone Medical and Dental Association in late November, 2014, the offer of treatment within the UK DMS ETF was made proactively and certainly not under pressure. The only constraint to admission of HCWs is capacity. Access to care is effectively the same at the UK-run ETF as the US-run facility in Liberia, although we appreciate that the compassionate wording within the US rules of eligibility5AnonMonrovia Medical Unit (Ebola Treatment Unit): US Public Health Service Commissioned Corps.http://www.timothypflaniganmd.com/wp-content/uploads/2014/11/Corps-MMU-ETU_Overview-Nov-7_2014_Final.pdfGoogle Scholar could affect the perception. We stress that no HCW in Sierra Leone has been refused admission to the UK DMS ETF. UK DMS remains committed (indeed has extended its commitment) to providing the highest level of care possible for all HCWs in Sierra Leone who present to the ETF, within its finite capacity. Results so far suggest that this level of care is reducing the case fatality rate of this dreadful disease, and we hope that as more experience is gained and new treatments are established, this rate will fall further, giving local HCWs the confidence of the highest standard of care available in the country and one that approaches, as near as possible, that available in the UK. We are members of the UK Defence Medical Service and are directly involved in deployment and management of clinical provision at the UK Defence Medical Services Ebola Treatment Facility in Sierra Leone. Sierra Leone doctors call for better Ebola care for colleaguesLocal doctors went on strike in Sierra Leone after it emerged that they would not be able to access a specialised British-run Ebola treatment unit for health-care workers. Miriam Shuchman reports. Full-Text PDF Ebola: protection of health-care workersThe Ebola outbreak in west Africa has taken a substantial toll on health-care workers in Guinea, Liberia, and Sierra Leone—not only doctors and nurses, but also other cadres including ambulance drivers, hospital cleaners, and burial team members. More than 600 of the nearly 17 000 cases of Ebola virus disease have been in health-care workers, more than half of them fatal. In today's issue of The Lancet we pay tribute to several of the health workers who have lost their lives to the disease since the outbreak began a year ago. Full-Text PDF

Diarrhoea in deployed soldiers is a fact of operational life. It is part of soldiering, has been documented as such as far back as the Old Testament (Deuteronomy 23 : 12–14) and should be accepted as such. Its persistence over the years has shown it to withstand attempts to defeat it,

Background It is increasingly recognised that diarrhoeal disease is an important contributor to disease non-battle injury (DNBI) rates on operations. Current data collection methods (J97/EPINATO) rely on self-presentation of patients to medical care, which is likely to under-record the true incidence of diarrhoea in theatre. Along with this, the data recording itself is less than adequate, with acknowledged issues in classification of diarrhoeal disease within J97/EPINATO categories.Methods Two post-tour diarrhoeal disease questionnaire surveillance exercises were carried out at the end of Operation HERRICK 6 (H6) and 10 (H10), respectively.Results Crude diarrhoeal disease attack rates were similar across the two surveillance periods with approximately 40% of troops questioned reporting at least one diarrhoeal illness episode. The severity of illness increased from H6 to H10 as measured by disease-related symptomatology and days ill and/or off work. Mission burden was substantial and increased in H10 compared with H6.Conclusions Diarrhoeal disease is a significant cause of DNBI on operations. Current data collection methodologies underestimate its incidence and true operational burden.

PURPOSE OF REVIEW:Diarrhoea among military travellers deployed globally in conflict and peacekeeping activities remains one of the most important health threats. Here we review recent advances in our understanding of the epidemiology, laboratory identification, treatment and chronic health consequences of this multi-cause infection, and consider the implications for public health management and future research.RECENT FINDINGS:The incidence of diarrhoea among deployed military personnel from industrialized countries to lesser developed countries is approximately 30% per month overall, with clinical incidence between 5 and 7% per 100 person-months. The risk appears to be higher early during deployment and is associated with poor hygienic conditions and contaminated food sources. Gaps remain in our understanding of the cause, given the lack of laboratory capability in austere conditions of deployment; however, recent advances in molecular methods of characterization hold promise in improving our detection capabilities. While there have been improvements in understanding of best treatments, more work needs to be done in transforming this knowledge into action and optimizing single-dose antibiotic treatment regimens. Finally, the under-recognized burden of chronic consequences of these infections is gaining awareness and reinforces the need to find effective preventive strategies.SUMMARY:Our understanding of the epidemiology of diarrhoea is improving but further research is needed to fully account for acute operational-focused health impacts as well as the chronic enduring disease impacts. Improved field diagnostics would be of great value to support these efforts.