ABSTRACT
Enterotoxigenic Escherichia coli (ETEC) has consistently been the predominant bacterial cause of diarrhea in many birth cohort- and hospital-based studies conducted in Egypt. We evaluated the pathogenicity of ETEC isolates in a birth cohort of children living in a rural community in Egypt. Between 2004 and 2007, we enrolled and followed 348 children starting at birth until their second year of life. A stool sample and two rectal swabs were collected from children during twice-weekly visits when they presented with diarrhea and were collected every 2 weeks if no diarrhea was reported. From routine stool cultures, five E. coli-like colonies were screened for ETEC enterotoxins using a GM1 enzyme-linked immunosorbent assay (ELISA). The isolates were screened against a panel of 12 colonization factor antigens (CFAs) by a dot blot assay. A nested case-control study evaluated the association between initial or repeat excretion of ETEC and the occurrences of diarrhea. The pathogenicity of ETEC was estimated in symptomatic children compared to that in asymptomatic controls. ETEC was significantly associated with diarrhea (crude odds ratio, 1.37; 95% confidence interval [CI], 1.24 to 1.52). The distribution of ETEC enterotoxins varied between the symptomatic children (44.2% heat-labile toxin [LT], 38.5% heat-stable toxin [ST], and 17.3% LT/ST) and asymptomatic children (55.5% LT, 34.6% ST, and 9.9% LT/ST) (P < 0.001). The CFAs CFA/I (n = 61), CS3 (n = 8), CS1 plus CS3 (n = 24), CS2 plus CS3 (n = 18), CS6 (n = 45), CS5 plus CS6 (n = 11), CS7 (n = 25), and CS14 (n = 32) were frequently detected in symptomatic children, while CS6 (n = 66), CS12 (n = 51), CFA/I (n = 43), and CS14 (n = 20) were detected at higher frequencies among asymptomatic children. While all toxin phenotypes were associated with diarrheal disease after the initial exposure, only ST and LT/ST-expressing ETEC isolates (P < 0.0001) were associated with disease in repeat infections. The role of enterotoxins and pathogenicity during repeat ETEC infections appears to be variable and dependent on the coexpression of specific CFAs.
Subject(s)
Diarrhea/microbiology , Enterotoxigenic Escherichia coli/classification , Enterotoxigenic Escherichia coli/isolation & purification , Escherichia coli Infections/microbiology , Case-Control Studies , Child, Preschool , Cohort Studies , Diarrhea/epidemiology , Egypt/epidemiology , Enterotoxigenic Escherichia coli/genetics , Enterotoxigenic Escherichia coli/physiology , Escherichia coli Infections/epidemiology , Feces/microbiology , Female , Humans , Immunoassay , Infant , Infant, Newborn , Male , Phenotype , Rural Population , Virulence Factors/analysisABSTRACT
Human challenges with enterotoxigenic Escherichia coli (ETEC) have broadened our understanding of this important enteropathogen. We report findings from the first challenge studies using ETEC-expressing colonization factor fimbria CS17 and CS19. LSN03-016011/A (LT, CS17) elicited a dose-dependent effect, with the upper dose (6 × 10(9) organisms) causing diarrhea in 88% of recipients. WS0115A (LTSTp, CS19) also showed a dose response, with a 44% diarrhea rate at 9 × 10(9) organisms. Both strains elicited homologous antifimbrial and anti-LT antibody seroconversion. These studies establish the relative pathogenicity of ETEC expressing newer class 5 fimbriae and suggest suitability of the LT|CS17-ETEC challenge model for interventional trials.
Subject(s)
Adhesins, Bacterial/biosynthesis , Enterotoxigenic Escherichia coli/pathogenicity , Escherichia coli Infections/microbiology , Escherichia coli Infections/pathology , Escherichia coli Proteins/biosynthesis , Virulence Factors/biosynthesis , Adhesins, Bacterial/immunology , Adolescent , Adult , Antibodies, Bacterial/blood , Bacterial Toxins/immunology , Diarrhea/microbiology , Diarrhea/pathology , Enterotoxigenic Escherichia coli/growth & development , Enterotoxins/immunology , Escherichia coli Proteins/immunology , Female , Human Experimentation , Humans , Male , Middle Aged , Virulence Factors/immunology , Young AdultABSTRACT
Vector-borne infections (VBI) are defined as infectious diseases transmitted by the bite or mechanical transfer of arthropod vectors. They constitute a significant proportion of the global infectious disease burden. United States (U.S.) Department of Defense (DoD) personnel are especially vulnerable to VBIs due to occupational contact with arthropod vectors, immunological naiveté to previously unencountered pathogens, and limited diagnostic and treatment options available in the austere and unstable environments sometimes associated with military operations. In addition to the risk uniquely encountered by military populations, other factors have driven the worldwide emergence of VBIs. Unprecedented levels of global travel, tourism and trade, and blurred lines of demarcation between zoonotic VBI reservoirs and human populations increase vector exposure. Urban growth in previously undeveloped regions and perturbations in global weather patterns also contribute to the rise of VBIs. The Armed Forces Health Surveillance Center-Global Emerging Infections Surveillance and Response System (AFHSC-GEIS) and its partners at DoD overseas laboratories form a network to better characterize the nature, emergence and growth of VBIs globally. In 2009 the network tested 19,730 specimens from 25 sites for Plasmodium species and malaria drug resistance phenotypes and nearly another 10,000 samples to determine the etiologies of non-Plasmodium species VBIs from regions spanning from Oceania to Africa, South America, and northeast, south and Southeast Asia. This review describes recent VBI-related epidemiological studies conducted by AFHSC-GEIS partner laboratories within the OCONUS DoD laboratory network emphasizing their impact on human populations.
Subject(s)
Communicable Diseases, Emerging/epidemiology , Global Health , Malaria/epidemiology , Military Medicine , Sentinel Surveillance , Animals , Arthropod Vectors , Communicable Diseases, Emerging/transmission , Drug Resistance , Humans , United States , ZoonosesABSTRACT
The mission of the Armed Forces Health Surveillance Center, Division of Global Emerging Infections Surveillance and Response System (AFHSC-GEIS) is to support global public health and to counter infectious disease threats to the United States Armed Forces, including newly identified agents or those increasing in incidence. Enteric diseases are a growing threat to U.S. forces, which must be ready to deploy to austere environments where the risk of exposure to enteropathogens may be significant and where routine prevention efforts may be impractical. In this report, the authors review the recent activities of AFHSC-GEIS partner laboratories in regards to enteric disease surveillance, prevention and response. Each partner identified recent accomplishments, including support for regional networks. AFHSC/GEIS partners also completed a Strengths, Weaknesses, Opportunities and Threats (SWOT) survey as part of a landscape analysis of global enteric surveillance efforts. The current strengths of this network include excellent laboratory infrastructure, equipment and personnel that provide the opportunity for high-quality epidemiological studies and test platforms for point-of-care diagnostics. Weaknesses include inconsistent guidance and a splintered reporting system that hampers the comparison of data across regions or longitudinally. The newly chartered Enterics Surveillance Steering Committee (ESSC) is intended to provide clear mission guidance, a structured project review process, and central data management and analysis in support of rationally directed enteric disease surveillance efforts.
Subject(s)
Disease Outbreaks/prevention & control , Gastrointestinal Diseases/epidemiology , Global Health , Military Medicine , Sentinel Surveillance , Communicable Diseases/epidemiology , Forecasting , Humans , Incidence , Infection Control , Laboratories , United StatesABSTRACT
Immune reconstitution inflammatory syndrome (IRIS) describes the initial clinical deterioration some patients manifest upon initiation of effective antiretroviral therapy (ART) for HIV infection. In this report we describe a case of IRIS manifesting as polyarticular gout, a previously unreported rheumatological manifestation of IRIS. A 53-year-old HIV-infected man with a history of intermittent attacks of gout and an initial CD4 count of 112 cells/microL and a viral load of >100,000 copies/mL presented to our institution with severe, refractory, polyarticular gout approximately 4 weeks after initiating ART. At this point, the patient demonstrated significant gains in his CD4 counts (103 cells/microL) and a greater than 3 log decline in his HIV-1- viral load. This episode was prolonged lasting for approximately 10 weeks and required hospitalization for the management of pain and control of inflammation. The temporal associations of this attack with the initiation of ART and the observed immunologic reconstitution make IRIS a clinical possibility.Monosodium urate crystals through their interactions with interleukin 1- beta, and neutrophilic synovitis play a critical role in the pathophysiology of gout. Defects in both neutrophil and macrophage function and imbalances in the cytokine milieu are documented in HIV infected patients. The introduction of ART results in restoration of neutrophil and macrophage function, declines in levels of the anti-inflammatory cytokine IL-10, and increases in levels of proinflammatory cytokines including IL-1 beta, which may provide the necessary milieu for the precipitation of attacks of severe polyarticular gout in the context of ART initiation.
Subject(s)
Anti-Retroviral Agents/therapeutic use , Arthritis, Gouty/etiology , HIV Infections/drug therapy , Immune Reconstitution Inflammatory Syndrome/complications , Humans , Male , Middle AgedABSTRACT
Enterotoxigenic Escherichia coli (ETEC) is a leading cause of diarrhea among travelers and pediatric populations worldwide. The tip-localized adhesin of colonization factor antigen (CFA)/I fimbriae was engineered as a donor strand complemented variant (dscCfaE) and delivered via transcutaneous immunization. Preclinical vaccine testing demonstrated safety, immunogenicity and efficacy. A series of open-label dose-escalating phase 1 studies evaluated a 3-dose (days 0, 21, 42) regimen via a transcutaneous skin patch. A total of forty-six subjects were enrolled into one of four vaccine dose levels (10, 50, 250, or 1250 µg) co-administered with single-mutant heat-labile enterotoxin (LTR(192G)). At the 50 µg dose level, ten subjects received the dscCfaE vaccine without LT(R192G). The vaccine was well tolerated with mild local vaccine site reactions characterized by an erythematous papular rash and pruritus, which were less frequent and reactive in the group not receiving LT(R192G). The frequency of responses to dscCfaE were moderate, whereas anti-toxin responses (serum IgA/IgG) ranged from 75 to 100% across groups that received LT(R192G). Antigen-specific antibody-secreting cell responses were elicited at all dose levels, but were generally low. Follow-on studies will optimize construct and route of delivery and assess efficacy in an ETEC challenge study.
Subject(s)
Bacterial Toxins , Enterotoxigenic Escherichia coli , Escherichia coli Infections , Escherichia coli Proteins , Escherichia coli Vaccines , Antibodies, Bacterial , Bacterial Toxins/genetics , Child , Enterotoxins/genetics , Escherichia coli Infections/prevention & control , Escherichia coli Proteins/genetics , Hot Temperature , Humans , Immunoglobulin A , MutationABSTRACT
BACKGROUND: Acinetobacter baumannii is usually associated with nosocomial pneumonia or bacteremia. Reports of A. baumannii skin and soft-tissue infection (SSTI) are uncommon. METHODS: We performed a retrospective review of 57 inpatients admitted to a naval hospital ship and identified 8 patients with A. baumannii-associated SSTI. Demographic and clinical characteristics were compared between these patients and 49 patients with A. baumannii infections that were not SSTIs. We also reviewed 18 cases of A. baumannii-associated SSTI from the literature. RESULTS: Our 8 cases of A. baumannii-associated SSTI were associated with combat trauma wounds. The median age of the patients was 26 years. Although not statistically significant, A. baumannii-associated SSTIs were more likely to be associated with gunshot wounds (75% vs. 55%) or external fixators (63% vs. 29%), compared with A. baumannii infections that were not SSTIs. Use of a central venous catheter and total parenteral nutrition was also more common for patients with SSTI. Our cases of A. baumannii-associated SSTI presented as cellulitis with a "peau d'orange" appearance with overlying vesicles and, when untreated, progressed to necrotizing infection with bullae (hemorrhagic and nonhemorrhagic). In our case series, all isolates were multidrug resistant, and clinical success was achieved for 7 of 8 patients with debridement and carbapenem therapy. CONCLUSIONS: A. baumannii-associated SSTI is an emerging infection in patients who experience trauma. Clinicians should be aware of the potential role of A. baumannii as a multidrug-resistant pathogen causing hospital-acquired SSTI, particularly when associated with previous trauma or use of invasive devices. It should be suspected in patients who experience trauma and have edematous cellulitis with overlying vesicles. Early empirical coverage for drug-resistant species (e.g., with carbapenem therapy), combined with debridement, is usually curative.
Subject(s)
Acinetobacter Infections , Acinetobacter baumannii/isolation & purification , Skin Diseases, Bacterial , Soft Tissue Infections , Warfare , Wounds and Injuries/complications , Acinetobacter Infections/epidemiology , Acinetobacter Infections/microbiology , Acinetobacter Infections/surgery , Acinetobacter baumannii/drug effects , Adolescent , Adult , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Carbapenems/therapeutic use , Debridement , Drug Resistance, Multiple, Bacterial , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Military Personnel , Skin Diseases, Bacterial/epidemiology , Skin Diseases, Bacterial/microbiology , Skin Diseases, Bacterial/surgery , Soft Tissue Infections/epidemiology , Soft Tissue Infections/microbiology , Soft Tissue Infections/surgery , Treatment Outcome , Wounds and Injuries/microbiology , Wounds and Injuries/physiopathology , Wounds, Gunshot/complications , Wounds, Gunshot/microbiology , Wounds, Gunshot/physiopathologyABSTRACT
INTRODUCTION: The present study, conducted between January 2004 and April 2007, explored the impact of household hygiene on the risk of bacterial diarrhea, using data from a prospective birth cohort of 348 infants in five villages in the Nile Delta in Egypt. METHODOLOGY: Neonates were enrolled at birth and followed up until 24 months of age. Children were visited twice a week to survey them for acute diarrhea. A detailed observational household hygiene survey was completed in-house every six months. Adjusted relative risk (aRR) of developing bacterial diarrhea was calculated for exposure to different hygiene variables and examined for specific bacterial pathogens. RESULTS: Exclusive breastfeeding reduced the risk of bacterial diarrhea by 70%, while bacterial diarrhea cases were 2.6 times higher in the warm season. Risk of Campylobacter diarrhea increased with the absence of barriers to keep birds and animals out of the eating area, the presence of garbage containers and a bathing facility within the compound, and the presence of feces on the floor of the bathing facility. Use of municipal water for drinking and cooking was associated with a lower risk of Campylobacter diarrhea. Risk of enterotoxigenic Escherichia coli diarrhea increased with uncovered garbage containers and the presence of liquid materials in the garbage containers, but decreased with the use of tap water in the washing facility. CONCLUSION: The results highlight some potential targets for interventions, such as expanding municipal water supply to all houses and comprehensive mass-media awareness programs to change hygiene-promoting behaviors and practices.
Subject(s)
Bacterial Infections/epidemiology , Bacterial Infections/prevention & control , Diarrhea/epidemiology , Diarrhea/prevention & control , Family Health , Hygiene , Animals , Child, Preschool , Cohort Studies , Data Collection , Egypt/epidemiology , Enterobacteriaceae/classification , Enterobacteriaceae/isolation & purification , Family Characteristics , Feces/microbiology , Female , Follow-Up Studies , Humans , Incidence , Infant , Infant, Newborn , Male , Prospective Studies , Risk Assessment , Rural PopulationABSTRACT
BACKGROUND: Influenza pandemics have significant operational impact on deployed military personnel working in areas throughout the world. The US Department of Defense global influenza-like illness (ILI) surveillance network serves an important role in establishing baseline trends and can be leveraged to respond to outbreaks of respiratory illness. OBJECTIVE: We identified and characterized an operationally unique outbreak of H3N2 influenza at Camp Lemonnier, Djibouti occurring simultaneously with the H1N1 pandemic of 2009 [A(H1N1)pdm09]. METHODS: Enhanced surveillance for ILI was conducted at Camp Lemonnier in response to local reports of a possible outbreak during the A(H1N1)pdm09 pandemic. Samples were collected from consenting patients presenting with ILI (utilizing a modified case definition) and who completed a case report form. Samples were cultured and analyzed using standard real-time reverse transcriptase PCR (rt-RT-PCR) methodology and sequenced genetic material was phylogenetically compared to other published strains. RESULTS: rt-RT-PCR and DNA sequencing revealed that 25 (78%) of the 32 clinical samples collected were seasonal H3N2 and only 2 (6%) were A(H1N1)pdm09 influenza. The highest incidence of H3N2 occurred during the month of May and 80% of these were active duty military personnel. Phylogenetic analysis revealed that sequenced H3N2 strains were genetically similar to 2009 strains from the United States of America, Australia, and South east Asia. CONCLUSIONS: This outbreak highlights challenges in the investigation of influenza among deployed military populations and corroborates the public health importance of maintaining surveillance systems for ILI that can be enhanced locally when needed.
Subject(s)
Disease Outbreaks , Influenza A Virus, H1N1 Subtype , Influenza A Virus, H3N2 Subtype , Influenza, Human/epidemiology , Military Personnel , Pandemics , Djibouti/epidemiology , Female , Humans , Influenza, Human/genetics , Influenza, Human/metabolism , Male , RNA, Viral/blood , Reverse Transcriptase Polymerase Chain Reaction , United StatesABSTRACT
BACKGROUND: At the onset of an influenza pandemic, when the severity of a novel strain is still undetermined and there is a threat of introduction into a new environment, e.g., via the deployment of military troops, sensitive screening criteria and conservative isolation practices are generally recommended. OBJECTIVES: In response to elevated rates of influenza-like illness among U.S. military base camps in Kuwait, U.S. Naval Medical Research Unit No. 3 partnered with local U.S. Army medical units to conduct an A(H1N1) pdm09 outbreak investigation. PATIENTS/METHODS: Initial clinical data and nasal specimens were collected via the existent passive surveillance system and active surveillance was conducted using a modified version of the World Health Organization/U.S. Centers for Disease Control and Prevention influenza-like illness case definition [fever (T > 100.5ËF/38ËC) in addition to cough and/or sore throat in the previous 72 hours] as the screening criteria. Samples were tested via real-time reverse-transcription PCR and sequenced for comparison to global A(H1N1) pdm09 viruses from the same time period. RESULTS: The screening criteria used in Kuwait proved insensitive, capturing only 16% of A(H1N1) pdm09-positive individuals. While still not ideal, using cough as the sole screening criteria would have increased sensitivity to 73%. CONCLUSIONS: The results of and lessons learned from this outbreak investigation suggest that pandemic influenza risk management should be a dynamic process (as information becomes available regarding true attack rates and associated mortality, screening and isolation criteria should be re-evaluated and revised as appropriate), and that military operational environments present unique challenges to influenza surveillance.
Subject(s)
Disease Outbreaks/prevention & control , Influenza, Human/diagnosis , Influenza, Human/epidemiology , Military Personnel , Cough/diagnosis , Cough/epidemiology , DNA, Viral/analysis , Fever/diagnosis , Fever/epidemiology , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza, Human/virology , Kuwait/epidemiology , Mass Screening/methods , Military Personnel/statistics & numerical data , Pharyngitis/diagnosis , Pharyngitis/epidemiology , Phylogeny , Real-Time Polymerase Chain Reaction , Risk Management , United StatesABSTRACT
Enterotoxigenic Escherichia coli (ETEC) is a major health problem for travelers to the Middle East. During the autumn months of 2005, 2007, and 2009, U.S. military personnel participated in Operation Bright Star (OBS) exercises in Egypt. Out of 181 military personnel enrolled in a diarrheal surveillance study, E. coli-like colonies were isolated from 170 patients. Isolates were tested for the detection of ETEC enterotoxins and colonization factors (CFs) using phenotypic and genotypic methods. Additionally, we studied the secular trends of ETEC isolates obtained from OBS studies since 1999. ETEC was isolated from 51.2% and 60.0% of the patients based on enzyme-linked immunosorbent assay and polymerase chain reaction (PCR), respectively. Heat stable (ST) was the dominant enterotoxin detected followed by heat labile (LT) and LTST. Additionally, we detected a CF in 59.7% and 67.6% of the ETEC-positive isolates using dot blot and PCR assays, respectively. The predominant CF isolated was CS6 followed by CS3.
Subject(s)
Diarrhea/microbiology , Enterotoxigenic Escherichia coli/genetics , Escherichia coli Infections/microbiology , Diarrhea/epidemiology , Egypt , Enterotoxigenic Escherichia coli/isolation & purification , Enterotoxins/genetics , Epidemiological Monitoring , Escherichia coli Infections/epidemiology , Fimbriae Proteins/genetics , Genotype , Humans , Military Personnel , Phenotype , Prevalence , United States/ethnology , Virulence Factors/geneticsABSTRACT
INTRODUCTION: We aimed to identify potential risk factors for intussusception (ISS) among children presenting to two pediatric hospitals in Egypt. METHODOLOGY: In this case-control study, enrolled children < 3 years old with ISS (confirmed radiologically and/or surgically) were matched by age and gender to controls admitted with acute non-abdominal surgical illnesses. Stool samples were collected and tested for various enteric bacteria, rotavirus, enteric adenoviruses (EA, 40 and 41) and astroviruses using commercially available ELISA diagnostic kits. RESULTS: From December 2004 to May 2009, 158 cases and 425 matched controls were enrolled. A history of diarrhoea and cough over the preceding four weeks of interview were more common in cases than controls, respectively. Children with mothers who had secondary education and above were 2.2 times more likely to have ISS than those whose mothers had a lower level of education. In spite of the low detection rate of EA infection (regardless of diarrhoea history) and asymptomatic rotavirus infection, they were detected in higher frequencies in cases than controls; however, infection with astrovirus and bacterial pathogens did not appear to be associated with increased risk of ISS. CONCLUSIONS: History of diarrhoea and cough over the four weeks preceding the study and maternal education above secondary level were potential risk factors for ISS. EA and asymptomatic rotavirus infection were detected in higher frequencies among cases than controls; however, association with ISS cannot be confirmed. Additional research is needed to confirm these findings and evaluate the pathogenesis which may link such infections with ISS.
Subject(s)
Gastroenteritis/complications , Intussusception/complications , Virus Diseases/complications , Adenovirus Infections, Human/complications , Adenovirus Infections, Human/virology , Adenoviruses, Human/isolation & purification , Case-Control Studies , Child, Preschool , Egypt , Feces/microbiology , Feces/virology , Female , Gastroenteritis/virology , Hospitals, Pediatric , Humans , Infant , Infant, Newborn , Male , Risk Factors , Rotavirus/isolation & purification , Rotavirus Infections/complications , Rotavirus Infections/virology , Virus Diseases/virologyABSTRACT
In 2005, sulphadoxine-pyrimethamine (SP) became the drug of choice for intermittent preventive treatment of Plasmodium falciparum malaria in pregnancy (IPTp) in Ghana. Reports suggest the use of SP by others to treat uncomplicated malaria. Because of the increased use of SP, the prevalence of mutations in the genes, dihydrofolate reductase (dhfr), and dihydropteroate synthetase (dhps), linked to SP resistance in P. falciparum were determined. Blood samples from 945 children with uncomplicated malaria collected at nine sites from 2003 to 2010 were analyzed using polymerase chain reaction and restriction fragment length polymorphism. Prevalence of the dhfr triple and dhfr plus dhps quadruple mutations showed significant increase in trend from 2003 to 2010 (χ(2) = 18.78, P < 0.001, χ(2) = 15.11, P < 0.001, respectively). For dhps double mutant G437 + E540 the prevalence was low (1.12%) caused by the very low prevalence of E540. Our findings show the wide use of SP in Ghana and therefore its use for IPTp needs to be closely monitored.
Subject(s)
Antimalarials/pharmacology , Drug Resistance , Malaria, Falciparum/parasitology , Plasmodium falciparum/drug effects , Pyrimethamine/pharmacology , Sulfadoxine/pharmacology , Alcohol Oxidoreductases , Alleles , Antimalarials/therapeutic use , Biomarkers , Dihydropteroate Synthase/genetics , Dihydropteroate Synthase/metabolism , Drug Combinations , Gene Expression Regulation, Enzymologic , Ghana/epidemiology , Health Policy , Humans , Infant , Malaria, Falciparum/drug therapy , Malaria, Falciparum/epidemiology , Plasmodium falciparum/enzymology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Population Surveillance , Pyrimethamine/therapeutic use , Sulfadoxine/therapeutic use , Tetrahydrofolate Dehydrogenase/genetics , Tetrahydrofolate Dehydrogenase/metabolism , Time FactorsABSTRACT
The present study demonstrates that multiple NoV genotypes belonging to genogroup II contributed to an acute gastroenteritis outbreak at a US military facility in Turkey that was associated with significant negative operational impact. Norovirus (NoV) is an important pathogen associated with acute gastroenteritis among military populations. We describe the genotypes of NoV outbreak occurred at a United States military facility in Turkey. Stool samples were collected from 37 out of 97 patients presenting to the clinic on base with acute gastroenteritis and evaluated for bacterial and viral pathogens. NoV genogroup II (GII) was identified by RT-PCR in 43% (16/37) stool samples. Phylogenetic analysis of a 260 base pair fragment of the NoV capsid gene from ten stool samples indicated the circulation of multiple and rare genotypes of GII NoV during the outbreak. We detected four GII.8 isolates, three GII.15, two GII.9 and a sole GII.10 NoV. Viral sequences could be grouped into four clusters, three of which have not been previously reported in Turkey. The fact that current NoV outbreak was caused by rare genotypes highlights the importance of norovirus strain typing. While NoV genogroup II is recognized as causative agent of outbreak, circulation of current genotypes has been rarely observed in large number of outbreaks.
Subject(s)
Caliciviridae Infections/virology , Gastroenteritis/virology , Norovirus , Adult , Caliciviridae Infections/epidemiology , Capsid Proteins/genetics , Disease Outbreaks , Female , Gastroenteritis/epidemiology , Genes, Viral , Genotype , Humans , Male , Military Personnel , Norovirus/classification , Norovirus/genetics , Norovirus/isolation & purification , Phylogeny , Turkey/epidemiology , United States/ethnology , Young AdultABSTRACT
We conducted clinic-based, influenza-like illness and diarrheal disease surveillance among U.S. service members participating in Operation Bright Star 2009. Epidemiologic data and samples were collected. Nasopharyngeal swab specimens were tested for viruses, and feces was tested for microbiologic, immunologic, and molecular diagnostics. A survey was used to collect self-reported data. From 1,529 surveys, 41% reported diarrheal disease and 25% reported respiratory illness (incidence rate = 62 of 100 versus 37 of 100 person-months; incidence rate ratio = 1.7, 95% confidence interval = 1.5-1.9). Enterotoxigenic Escherichia coli was identified in 74% (69 of 93) of fecal samples. In the influenza-like illness case series, 17% (9 of 52) were positive for influenza A; all were positive for pandemic (pH1N1) 2009 virus. Rates of decreased work performance reported by patients with diarrhea and influenza-like illness were similar (46% versus 48%; P = 0.8). Diarrheal diseases and respiratory illness remain common among deployed military personnel, with important operational impact. Despite an ongoing influenza pandemic, diarrheal disease incidence was higher than that of respiratory illness.
Subject(s)
Diarrhea/epidemiology , Disease Outbreaks , Military Personnel , Respiratory Tract Diseases/epidemiology , Adult , Egypt/epidemiology , Feces/microbiology , Feces/parasitology , Female , Humans , Incidence , Influenza A virus/genetics , Male , Poisson Distribution , RNA, Viral/chemistry , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction , United States/ethnologyABSTRACT
INTRODUCTION: Between 2004 and 2007, a birth cohort of Egyptian children was analysed to evaluate the epidemiology of enteric diseases. METHODOLOGY: A stool sample was collected from the study children every two weeks as well as whenever they experienced diarrhea. Samples were tested for routine bacterial pathogens as well as enteropathogenic viruses and parasites. A secondary goal of the study was to evaluate the burden of less commonly reported pathogens including Aeromonas hydrophila. RESULTS: Of the 348 study subjects, 79 had A. hydrophila isolated from their stool at some point during the study. Thirty-six children had exclusively symptomatic (S) infections while 33 had exclusively asymptomatic (AS) infections. However, 10 children had both S and AS infections. Among symptomatic cases, A. hydrophila was the sole pathogen isolated 36% of the time. An important aspect of A. hydrophila associated diarrhea was the high level of resistance to cephalosporins. CONCLUSION: Although relatively uncommon, A. hydrophila was found to be associated with diarrhea among children living in Egypt and was frequently multi-drug resistant.
Subject(s)
Aeromonas hydrophila/isolation & purification , Diarrhea/epidemiology , Gram-Negative Bacterial Infections/epidemiology , Diarrhea/microbiology , Diarrhea/pathology , Egypt/epidemiology , Feces/microbiology , Female , Gram-Negative Bacterial Infections/microbiology , Gram-Negative Bacterial Infections/pathology , Humans , Infant , Male , Prevalence , Rural PopulationABSTRACT
INTRODUCTION: Acute diarrhea continues to be a major cause of morbidity and mortality in children from developing countries. Determination of the frequency of diarrhea in an area, along with the proportion of disease caused by specific enteric agents of different origins, is considered the first step in controlling diarrheal diseases. METHODOLOGY: From 2005 to 2007, a hospital-based surveillance was conducted in two locations in Egypt to determine the causes of acute diarrhea in children younger than 5-years seeking treatment. Five additional enteric viral and parasitic pathogens were tested using commercially-available enzyme immunoassays (EIA) to re-evaluate the prevalence of diarrheal pathogens in undiagnosed cases. RESULTS: Adenovirus, astrovirus, norovirus and G. lamblia were detected as the sole pathogen in 2% (n=34), 3% (n=56), 9% (n=191) and 7% (n=146) of the cases, respectively. E. histolytica was never detected as the sole pathogen. The percentage of diarrheal cases with a known cause increased significantly, from 48% (n=1,006) to 74% (n=1,568) (P < 0.0001). CONCLUSION: In our study, the incorporation of immunoassays yielded useful data in identifying pathogens in previously pathogen-negative diarrhea cases.
Subject(s)
Adenoviridae/isolation & purification , Diarrhea/parasitology , Diarrhea/virology , Giardia lamblia/isolation & purification , Mamastrovirus/isolation & purification , Norovirus/isolation & purification , Acute Disease/epidemiology , Adenoviridae/pathogenicity , Adenoviridae Infections/diagnosis , Adenoviridae Infections/epidemiology , Astroviridae Infections/diagnosis , Astroviridae Infections/pathology , Caliciviridae Infections/diagnosis , Caliciviridae Infections/epidemiology , Child, Preschool , Diarrhea/epidemiology , Diarrhea/microbiology , Egypt/epidemiology , Feces/microbiology , Feces/parasitology , Feces/virology , Giardia lamblia/pathogenicity , Giardiasis/diagnosis , Giardiasis/epidemiology , Humans , Immunoenzyme Techniques , Infant , Mamastrovirus/pathogenicity , Norovirus/pathogenicity , Prevalence , Reagent Kits, Diagnostic , Seasons , Sensitivity and SpecificityABSTRACT
Volunteer challenge with enterotoxigenic Escherichia coli (ETEC) has been used for four decades to elucidate the pathogenesis and immune responses and assess efficacy of various interventions. We performed a systematic review of these studies and a meta-analysis of individual patient-level data (IPD) from a subset of studies using standard methodology. We identified 27 studies of 11 ETEC strains administered to 443 naive subjects at doses from 1×10(6) to 1×10(10) colony forming units (cfu). Diarrhea attack rates varied by strain, dose and enterotoxin. Similar rates were seen at doses of 5×10(8) to 1×10(10)cfu with the three most commonly used strains B7A, E24377A, H10407. In IPD analysis, the highest diarrhea attack rates were seen with strains B7A, H10407 and E24377A. The H10407 induced significantly higher stool output than the other strains. Additionally, the rate of output was different across strains. The risk of diarrhea, abdominal cramps, nausea and headaches differed significantly by ETEC strain. An increased risk of nausea, abdominal cramps and headaches was seen for females. Baseline anti-LT IgG titers appeared to be associated with a decrease risk of diarrhea outcomes, a trend not seen with anti-LT IgA or seen consistently with anti-colonization factor antibodies. Neither early antibiotic treatment nor diarrhea duration significantly affected the frequency or magnitude of serologic responses. These studies have served as an invaluable tool in understanding disease course, pathogenicity, innate immune responses and an early assessment of product efficacy. When designing and planning experimental ETEC infection studies in this age of increased ethical scrutiny and growing appreciation of post-infectious sequelae, better understanding of available data is essential.