Enteropathogens Associated with Cases of Gastroenteritis in a Rural Population in Jordan L

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ORIGINAL ARTICLE 10.1111/j.1469-0691.2004.00891.x

Enteropathogens associated with cases of gastroenteritis in a rural population in Jordan L. F. Nimri1 and M. Meqdam2

1Department of Medical Laboratory Sciences and 2Department of Biological Sciences, Jordan University of Science & Technology, Irbid, Jordan

ABSTRACT Stool specimens were collected from 180 patients belonging to a population of recently settled Bedouins in Jordan who presented with acute or persistent diarrhoea and other symptoms, and from 100 non- diarrhoeal controls. All samples were examined for parasites and bacterial pathogens by culture and PCR. Bacterial isolates were tested for their susceptibility to common antimicrobial agents. Pathogens and potential enteropathogens were identified from 140 (77.8%) of the patients, with more than one pathogen being recovered from 67 (37.2%) patients. Potentially pathogenic parasites were observed in 90 (50%) patients; those that were associated significantly with diarrhoea were Giardia lamblia, Blastocystis hominis, Cryptosporidium spp., Entamoeba histolytica and Cyclospora cayetanensis. Pathogenic bacteria were isolated from 72 (40%) patients, and, of these, 62.5% were resistant to at least one antibiotic, and 30.6% of these were multiresistant. Diarrhoeagenic Escherichia coli strains were found in 14.3% of the patients and 2.9% of the control subjects (not statistically significant). The most common enteropathogenic bacteria found were Shigella spp., Campylobacter jejuni and Yersinia enterocolitica. Unusual bacterial species were the predominant organisms recovered in a few cases and could represent a possible cause of diarrhoea. Overall, there was a high endemicity of diarrhoeal disease in the area studied. Risk factors that correlated significantly with contracting diarrhoea were socio-economic status, education, use of unchlorinated well or tank water, and a low level of personal hygiene. Keywords Diarrhoea, enteric bacteria, gastroenteritis, parasites Original Submission: 25 June 2003; Accepted: 11 September 2003 Clin Microbiol Infect 2004; 10: 634–639

the death of 4.6–6 million children annually in INTRODUCTION Asia, Africa and America [2]. Morbidity is also Few outside the field of public health fully appre- important in poor countries. In Jordan, as part of a ciate the extent to which gastrointestinal illness general improvement in the quality of life, local affects human health across the globe. There are programmes of diarrhoeal disease control were difficulties in deriving a precise number of cases instituted by the Ministry of Health, including globally, as the symptoms associated with these promotion of breast-feeding, oral rehydration infections are quite diverse and it can be difficult to therapy and specific health education. However, classify and diagnose the associated infection. The despite the improvement in health services in the range of symptoms associated with infections of Badia, a rural area in the northeastern part of the gastrointestinal tract extends beyond diarrho- Jordan, diarrhoeal illnesses still represent an eal illness and gastroenteritis. However, the high important cause of infectious morbidity in chil- endemic rate of gastrointestinal disease in both dren as well as in adults. Diarrhoea is the third developed and developing countries still receives most common diagnosis in outpatients seen at the little attention [1]. Diarrhoeal disease is a frequent health centres in the area, exceeded only by illness in developing countries, and contributes to respiratory and urinary tract infections. Causes of diarrhoea in areas of endemicity Corresponding author and reprint requests: L. F. Nimri, involve a wide variety of bacteria, viruses and Department of Medical Laboratory Sciences, Jordan University of Science & Technology, PO Box 3030, Irbid 22110, Jordan protozoa. Poor quality food hygiene, water and E-mail: [email protected] sanitation are common in communities with high

2004 Copyright by the European Society of Clinical Microbiology and Infectious Diseases Nimri and Meqdam Enteropathogens associated with gastroenteritis 635 levels of diarrhoeal disease. Underlying condi- modified Ziehl–Neelsen procedure for enteric coccidia. tions, such as malnutrition, which increase the Trichrome-stained slides were examined when a suspected protozoan pathogen was observed in the iodine wet mount. risk of contracting diarrhoea, are also common in this area. These factors combine to facilitate the Bacteriological studies spread of enteropathogens, and epidemics are Enteropathogens, including the classic pathogenic Enterobac- common in such settings [3]. The present study teriaceae, were all investigated by culture, PCR, or both. Faeces investigated the occurrence of enteric pathogens were inoculated on blood agar, Salmonella–Shigella (S-S) agar, in patients with persistent or acute diarrhoea MacConkey agar (Biofilchem, Roseto, Italy), sorbitol MacCon- during a period of 2 years in the Jordan Badia key agar and Yersinia selective agar (Oxoid, Basingstoke, UK). Selective and differential media were used for isolating region, which is an area populated with recently Salmonella, Shigella, Yersinia spp. and Escherichia coli. For settled Bedouins. The study was conducted in Salmonella enrichment, faeces were inoculated in Selenite-F order to elucidate the aetiologies of diarrhoeal broth, incubated at 37C for 18 h, and subcultured on S-S agar; disease and risk factors in the Badia population. this was followed by incubation at 37C for 24–48 h. Suspected Yersinia spp. were selected as lactose-negative colonies from Apart from well-described enteropathogens, such MacConkey primary plates, and were incubated at 28C. as Shigella and Salmonella spp., particular attention Yersinia spp. were identified after inoculation of a stool in was paid to identifying other bacteria and intes- 10 mL of tryptose broth and incubation for 3 weeks at 4C, tinal parasites not previously detected, in order to with subsequent subculture on Yersinia selective agar. All characterise local strains of these pathogens and plates were examined, and putative colonies of enteropathogenic bacteria were identified by standard biochemical meth- assess their prevalence and pathogenicity in this ods, including the API 20E system (bioMe´rieux, Marcy l’Etoile, population. France). Campylobacter jejuni was detected only by PCR. Disk susceptibility tests were performed by a standard agar disk diffusion technique, as recommended by the National Committee for Clinical Laboratory Standards [4]. Sixteen MATERIALS AND METHODS antimicrobial agents were tested in order to obtain epidemi- Study area and patients ological information about susceptibility and resistance, namely ampicillin, carbenicillin, ceftriaxone, clindamycin, The study was conducted over a 2-year period in the Badia chloramphenicol, doxicillin, gentamicin, kanamycin, lincomy- region, a rural area in northeastern Jordan. This area has 12 000 cin, methicillin, nalidixic acid, neomycin, tetracycline, trimeth- inhabitants, most of whom are small-scale farmers of low socio- oprim–sulphamethoxazole (co-trimoxazole), erythromycin economic status. In total, 180 stool specimens were collected and vancomycin (for the Gram-positive isolates). The disk from patients diagnosed with gastroenteritis. All subjects content was 30 lg, except for ampicillin, doxicillin, gentamicin, consented to the collection of the specimen. Acute diarrhoea lincomycin and methicillin (all 10 lg), co-trimoxazole was defined (as reported by the patient) as passing three or (23.75 lg), and erythromycin (15 lg). ‘Non-susceptible’ refers more loose or watery stools within an 8-h period for < 6 days to resistant and intermediately resistant isolates. before presentation, accompanied by nausea, vomiting, ab- dominal pain or cramps. Other reported symptoms were bloody diarrhoea and muscle pain. Chronic or persistent DNA extraction diarrhoea was defined in the same way, except that the period DNA was extracted from the specimens with a Wizard of diarrhoea was > 10 days. One hundred stool specimens were Genomic DNA Purification kit (Promega, Madison, WI, also collected from non-diarrhoeal control subjects who were USA), following the manufacturer’s instructions for the puri- seen for reasons other than gastrointestinal disease (e.g., fication of DNA from a stool. Final pellets were resuspended in dermatology). Pre-coded questionnaires were completed for 50 lL TE (10 mM Tris, 1 mM EDTA, pH 7.2). each subject at the time of specimen collection to record demographic details, the clinical history and physical signs. All specimens were processed within 2 h of collection for bacterial DNA amplification and parasitological studies. Bacterial isolates were stored for The multiplex DNA Detect Multi-Enteric 4 PCR Kit (Vita-Tech subsequent identification. Patients with diarrhoea were treated International, Markham, Ontario, Canada) was used for direct with oral rehydration therapy and, when necessary, appro- amplification of four pathogens, namely Salmonella spp., Shig. priate antibiotics were selected on the basis of the culture dysenteriae, C. jejuni and Y. enterocolitica, in stool samples. The results. primers used in the kit are genus- or species-specific and designed to amplify a highly conserved region within the 16S Laboratory methods rRNA gene of the four pathogens. Each reaction mixture contained 5 lLof10· PCR buffer (no MgCl2), 25 mM MgCl2, Parasitological studies 5 lL of the Multi-Enteric 4 primer mix, 5 mM dNTP mix, 2 U For parasite detection, saline and iodine suspensions prepared Taq DNA polymerase and 5 lL of the DNA sample, in a total from fresh specimens were examined under the microscope, volume of 50 lL sterile deionised water. The positive control allowing the observation of living and moving trophozoite provided with the kit was used, while PCR mixes with no stages of protozoa. All samples were also processed by a sample and DNase-free water were used as negative controls formalin-ether sedimentation technique and stained with a to monitor cross-contamination. All PCRs were carried out in a

2004 Copyright by the European Society of Clinical Microbiology and Infectious Diseases, CMI, 10, 634–639 636 Clinical Microbiology and Infection, Volume 10 Number 7, July 2004

GeneAmp 9700 thermal cycler (Perkin-Elmer, Emeryville, CA, association of Blastocystis hominis with diarrhoea USA) with cycling conditions of 94C for 5 min, followed by observed in 54 patients was considered to be 35 cycles of 94C for 30 s, 58C for 45 s and 72C for 45 s, and a final extension at 72C for 5 min, followed by cooling at 4C for significant only when this organism was found as a minimum of 10 min. Reaction products (20 lL) were ana- a single parasite and in large numbers (‡ 5 lysed on an agarose 3% w ⁄ v gel stained with ethidium organisms ⁄·400 field) with no bacterial patho- bromide. gens; this was the case for 32 patients. The Three suspected E. coli colonies were transferred from commonest parasites associated significantly with MacConkey agar to brain–heart infusion agar, Simmons’ citrate agar, and lysine iron agar. Citrate-negative cultures diarrhoea were Giardia lamblia, Entamoeba histoly- were identified further with an E. coli DNA Detect Kit (Vita- tica, Cryptosporidium and Cyclospora cayetanensis Tech International) specific for E. coli 0157:H7. The PCR (Table 1). Other pathogenic parasites observed conditions used were the same as described above. occasionally included Hymenolepis nana (eight Other strains of E. coli (enterotoxigenic, enteropathogenic, shiga toxin-producing, and enteroaggregative) were detected patients), Ascaris lumbricoides (eight), Dientamoeba and characterised by PCR amplification of specific genes as fragilis (four), and Isospora belli (three). Non- described previously [5]. E. coli strains ATCC 35401 (LT1 toxin, pathogenic parasites, such as Entamoeba coli ST1 toxin), ATCC 43886 (LT1 toxin) and ATCC 43894 (stx1, (20 patients), Endolimax nana (15), Iodomoeba buts- stx2, eaeA1) were used as positive controls in each batch of chlii (eight) and Chilomastix mesnelli (seven), were PCRs. also observed either independently or in association with other parasites or bacteria. Statistical analysis Enteropathogenic bacteria were isolated from The association between diarrhoea and potential risk factors as fewer patients (72) than were parasites. The recorded in the questionnaire was assessed. Odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were species associated significantly with diarrhoea obtained by multiple logistic regression analysis using SAS v. were C. jejuni (ten patients), and five pathogenic 6.12 for Windows (SAS Institute, Cary, NC, USA). members of the family Enterobacteriaceae (50 patients; Table 1). Diarrhoeagenic E. coli strains were found in 20 patients, and in four of RESULTS the healthy controls, but the difference was not Patients statistically significant. E. coli O157:H7 was detected in ten patients, but not in the control subjects. Potential enteric pathogens were identified for Non-enterotoxigenic E. coli strains were isolated 140 (77.8%) of 180 patients (Table 1). The average from ten patients: eaeA-positive enteropathogenic age of the patients was 48 years (range: E. coli from six patients was accompanied by 12–84 years). Children aged < 12 years in the enteroaggregative E. coli in two patients. The same area were studied separately. More than shiga toxin-encoding gene of enterotoxigenic one pathogen was recovered from 67 (47.9%)of E. coli was found in strains isolated from three the 140 ‘positive’ patients. No pathogens were diarrhoeal episodes, and the LT1 toxin gene was detected for the other 40 patients. found in one. The other pathogens included Potentially pathogenic parasites were observed Shigella spp. (15 patients and including eight Shig. in 90 (64.3%) of the 140 ‘positive’ patients. The dysenteriae), Y. enterocolitica and Salmonella spp. (Table 1). Y. enterocolitica, identified by the API system and by PCR, was isolated from patients Table 1. Pathogenic and potentially pathogenic microorganisms isolated from 140 of 180 patients with gastroen- who had symptoms consistent with yersiniosis, teritis in the Badia region of Jordan e.g., persistent fever and gastrointestinal symp-

a toms; two patients had arthritis, and two patients Organism isolated No. of patients reported night sweats. Blastocystis hominis 54 Giardia lamblia 36 Unusual species were isolated either independ- Entamoeba histolytica 18 ently or with other microorganisms. These were Cryptosporidium spp. 15 Cyclospora cayetanensis 13 associated with the symptoms and were suspec- Diarrhoeagenic E. coli 20 ted as possible aetiological agents only when they Shigella spp. 15 Campylobacter jejuni 10 were the sole and predominant organisms recov- Yersinia enterocolitica 8 Salmonella spp. 7 ered. These were Citrobacter koseri (two patients), Other bacterial species 12 Chryseobacterium meningosepticum (two), Enterob- aMore than one pathogen was isolated from 67 patients. acter cloacae (two), Hafnia alveli (one), Eikenella

2004 Copyright by the European Society of Clinical Microbiology and Infectious Diseases, CMI, 10, 634–639 Nimri and Meqdam Enteropathogens associated with gastroenteritis 637 corrodens (one), Morganella morganii (one) and enteropathogenic bacterium was E. coli, which Serratia marcescens (three). was isolated from four healthy controls. The most severe symptoms were reported in patients with E. coli O157:H7, Ent. histolytica and DISCUSSION Shig. dysenteriae, where blood, mucus and many leukocytes were observed in the stool. The age The present study revealed that protozoan para- range of the patients with Ent. histolytica was sites were the microorganisms associated most 12–67 years, while that for Shig. dysenteriae was frequently with gastroenteritis in the Badia region 16–57 years. Cases of diarrhoea that exceeded of Jordan. This was true for cases of both acute 2 weeks in duration were associated with infec- and persistent diarrhoea. To our knowledge, this tions with Cryptosporidium and Cyclospora. Coin- is the first clinical study on the aetiologies fections with more than one pathogen were of gastroenteritis and diarrhoea in this rural area common, and were associated with severe symp- of Jordan. There was a relatively low yield of toms. Two parasites were observed in 55 enteropathogenic bacteria from stool samples of patients, two bacterial pathogens were detected patients with diarrhoea, although E. coli O157:H7, in six patients, and a parasite with a bacterial Ent. histolytica and Shig. dysenteriae were associ- pathogen in six patients. Infections with entero- ated with severe symptoms and visibly bloody pathogens were not normally accompanied by specimens. The aetiological agents could not be fever except in children. Shig. dysenteriae, Sal- determined for 40 (22.2%) of the 180 patients monella spp. and Y. enterocolitica isolates investigated. The causative agents might be rota- were identified further with the API 20E system virus, or non-infectious causes, such as chemical and were all confirmed with the Multi-Enteric 4 exposure, oral antibiotics, stress, food allergies or PCR kit. dietary indiscretion. The problem of pinpointing In total, 45 (62.5%) bacterial isolates were an associated organism is difficult, even in out- resistant or intermediately–resistant to at least breaks of gastrointestinal illness [1]. one antibiotic, and 22 (30.6%) were multiresistant The predominant organisms isolated were (i.e., to two or more antibiotics). Resistance was mainly protozoa, such as G. lamblia, B. hominis, most common to tetracycline (20 isolates; 44.4%), Ent. histolytica and Cryptosporidium, and members ampicillin (17 isolates; 37.8%) and co-trimoxazole of the Enterobacteriaceae, mainly E. coli, Shig. (13 isolates; 28.9%). Almost all strains tested of dysenteriae and C. jejuni. E. coli O157:H7 was Shigella spp., Salmonella spp. and enteropathogen- detected in ten patients, but not in the control ic E. coli were non-susceptible to ampicillin, subjects, while non-enterotoxigenic strains were tetracycline and erythromycin, but were suscept- also isolated from ten patients. Moreover, entero- ible to ceftriaxone and chloramphenicol. These pathogenic strains were found more commonly, pathogens were detected more frequently during independent of the clinical picture of the subjects. the warm months, which start in May and These findings are in agreement with other continue until the end of September. studies conducted in developing countries that The risk factors that correlated significantly reported one or more of these pathogens [2,6]. with contracting diarrhoea were: low socio-eco- Parasites such as Ascaris and H. nana might be nomic status (OR, 2.1; 95% CI, 2.0–2.2; p 0.001); responsible for some of the symptoms, but were low level of education (OR, 3.2; 95% CI, 3.0–4.0; not considered to be the causative agent of p 0.001); use of unchlorinated well or tank water diarrhoea. Uncommon parasites reported for (OR, 2.9; 95% CI, 2.6–3.3; p 0.001); and a low level the first time were C. cayetanensis, I. belli and of personal hygiene (OR, 2.7; 95% CI, 1.7–4.0; D. fragilis. Other studies of all forms of acute p 0.001). diarrhoea in developing countries have reported Campylobacter and Salmonella to be the predominant organisms [7,8], with Shigella infections being Controls the most common among adults, particularly The commonest parasites isolated from the 100 those with severe illness associated with bloody healthy controls were B. hominis (eight subjects), stools [9,10]. G. lamblia (ten), Ent. coli (12), End. nana (seven), This study reports the isolation of several I. butschlii (three) and C. mesnelli (two). The only uncommon potential bacterial pathogens for the

2004 Copyright by the European Society of Clinical Microbiology and Infectious Diseases, CMI, 10, 634–639 638 Clinical Microbiology and Infection, Volume 10 Number 7, July 2004

first time in Jordan. These organisms were ACKNOWLEDGEMENTS isolated either individually or in association with The authors thank the physicians and staff in the Badia health other microorganisms from patients, but not centres for their assistance and cooperation during the collec- from the control subjects. They were considered tion of the specimens. This study was supported financially by to constitute a possible aetiology of diarrhoea the Higher Council for Science and Technology in Jordan when they were the predominant organism (grant number 129 ⁄ 99). recovered. These uncommon potential pathogens included Cit. koseri [11,12], Chrys. meningosepti- REFERENCES cum [13], Eik. corrodens [14,15], Entero. cloacae 1. Payment P, Riley MS. Resolving the global burden of gastro- [12,16–19], H. alvei [20–24], M. morganii [12,25– intestinal illness: a call for action, a report from the American 27], and Serratia spp. [18,28]. The presence of Academy of Microbiology. Washington, DC: American non-pathogenic parasites in the non-diarrhoeal Academy of Microbiology, 2002. control subjects indicates a common source of 2. Torres ME, Pi’rez MC, Schelotto F et al. Etiology of children’s diarrhea in Montevideo, Uruguay: associated infection in this population. pathogen and unusual isolates. J Clin Microbiol 2001; 39: One of the limitations of the present study is 2134–2139. that not all patients with diarrhoea were enrolled 3. Gascoń J, Vargas M, Schellenberg D et al. Diarrhea because of unavailability of the specimen at the in children under 5 years of age from Ifakara, Tanzania: time the patients were seen in the health centres. a case-control study. J Clin Microbiol 2000; 38: 4459– 4462. In addition, a delay of > 2 h in delivering some of 4. National Committee for Clinical Laboratory Standards. the specimens to the laboratory for processing Performance standards for antimicrobial disk susceptibility tests, could be responsible for the low culture yield of 4th edn. Approved standard M2-A4. Villanova, PA: bacteria, although all specimens were kept refri- NCCLS, 1990. 5. Vargas M, Gascoń J, Gallardo F, Jimenez de Anta MT, gerated until processed. However, the results are Vila J. Prevalence of diarrheagenic Escherichia coli strains probably representative of the parasites and detected by PCR in patients with traveler’s diarrhea. Clin enteric bacteria prevalent over the 2-year period Microbiol Infect 1998; 4: 682–688. of the study. 6. Albert MJ, Faruque ASG, Faruque SM, Sack RB, Mahala- From the results obtained, it is clear that many nabis D. Case-control study of enteropathogens associated with childhood diarrhea in Dhaka, Bangladesh. J Clin enteropathogenic bacteria and parasites are Microbiol 1999; 11: 3458–3464. endemic in the Badia region of Jordan. These 7. Goodman LJ, Trenholme GM, Kaplan RL. Empiric pathogens are all water- or food-borne, and a antimicrobial therapy of domestically acquired acute multivariate analysis of the demographic data diarrhea in urban adults. Arch Intern Med 1990; 150: 541– 546. revealed that the factors which correlated signi- 8. Gurrant RL, Hughes JM, Lima NL, Crane J. Diarrhea in ficantly with diarrhoea, and might have lead to developing countries: magnitude, special settings, and transmission of these pathogens, included low etiologies. Rev Infect Dis 1990; 12(suppl 1): S41–S50. socio-economic status, low level of education, 9. Blaser MJ, Wells JG, Feldman RA, Pollard RA, Allen JR. use of unchlorinated well or tank water, and a Collaborative Diarrheal Disease Study Group. Campylo- bacter enteritis in the United States: a multicenter study. low level of personal hygiene. These factors Ann Intern Med 1983; 98: 360–365. reflect the living conditions, lifestyle and envi- 10. Talan DA, Moran GJ, Newdow M et al. Etiology of bloody ronmental conditions of the population. The diarrhea among patients presenting to United States burden of gastrointestinal illness is not limited Emergency Departments: prevalence of Escherichia coli O157:H7 and other enteropathogens. Clin Infect Dis 2001; to those living in poverty. Even in developing 32: 573–580. countries, the level of gastrointestinal disease 11. Cieslik A. Taxonomy of Citrobacter rods found in human associated with the faecal–oral route of transmis- specimens. Med Dos Microbiol 1999; 51: 289–299. sion could be decreased significantly by imple- 12. Jertborn M, Svennerholm AM. Enterotoxin-producing menting relatively simple strategies, such as bacteria isolated from Swedish travelers with diarrhoea. Scand J Infect Dis 1991; 23: 473–479. better wastewater treatment and hygiene educa- 13. Chang Chien HY, Chiu NC, Li WC, Huang FY. Charac- tion. Such strategies could alleviate a great deal teristics of neonatal bacterial meningitis in a teaching of unnecessary suffering and loss of productivity, hospital in Taiwan from 1984–1997. J Microbiol Immunol reduce the number of lives lost to these diseases, Infect 1984; 33: 100–104. 14. Chen CK, Wilson ME. Eikenella corrodens in human oral and result in significant savings in health care and non-oral infections: a review. J Periodontol 1992; 63: costs [1]. 941–953.

2004 Copyright by the European Society of Clinical Microbiology and Infectious Diseases, CMI, 10, 634–639 Nimri and Meqdam Enteropathogens associated with gastroenteritis 639

15. Gasser I, Moreno G, Ferrer A, Capdevila JA, Valle I. 23. Ridell J, Siitonen A, Paulin L, Mattila L, Korkeala H, Eikenella corrodens: five year experience in a general Albert MJ. Hafnia alvei in stool specimens of patients with hospital. Enferm Infect Microbiol Clin 1999; 17: 394–397. diarrhea and healthy controls. J Clin Microbiol 1994; 32: 16. Klipstein FA, Enger RF, Short HB. Enterotoxigenicity of 2335–2337. colonizing coliform bacteria in tropical sprue and blind- 24. Ridell J, Siitonen A, Paulin L, Lindroos O, Korkeala H, loop syndrome. Lancet 1978; 12: 342–344. Albert MJ. Characterization of Hafnia alvei by biochemical 17. Amenta M, Dalle Nogare ER, Colomba C et al. Intestinal tests, random amplified polymorphic DNA PCR, and protozoa in HIV-infected patients: effect of rifaximin in partial sequencing of 16S rRNA gene. J Clin Microbiol 1995; Cryptosporidium parvum and Blastocystis hominis infections. 33: 2372–2376. J Chemother 1999; 11: 391–395. 25. Cafferkey MT, Buckley TF, O’Morain CA. Association of 18. Wadstrom T, Aust-Kettis A, Habte D et al. Enterotoxin- reactive arthropathy and Morganella morganii cross react- producing bacteria and parasites in stools of Ethiopian ing with Yersinia enterocolitica. Scand J Infect Dis 1988; 20: children with diarrheal disease. Arch Dis Child 1976; 51: 439–442. 865–870. 26. Muller HE. Occurrence and pathogenic role of Morganella– 19. Back E, Jonsson M, Wadstrom T. Enterotoxin-producing Proteus–Providencia group bacteria in human feces. J Clin bacteria in stools from Swedish United Nations soldiers in Microbiol 1986; 23: 404–405. Cyprus. Infection 1978; 6: 116–120. 27. Ahren CM, Jertborn M, Herclik L, Kaijser B, Svennerholm 20. Albert MJ, Alam K, Islam M et al. Hafnia alvei, a probable AM. Infection with bacterial enteropathogens in Swedish cause of diarrhea in humans. Infect Immun 1991; 59: 1507– travelers to South-East-Asia—a prospective study. Epi- 1513. demiol Infect 1990; 105: 325–333. 21. Albert ME, Farouk S, Ansaruzaman KM et al. Sharing of 28. McLoughlin LC, Nord KS, Joshi VV, Oleske JM, Connor virulence-associated properties at the phenotypic and EM. Severe gastrointestinal involvement in children with genetic levels between enteropathogenic Escherichia coli the acquired immunodeficiency syndrome. J Pediatr Gast- and Hafnia alvei. J Med Microbiol 1992; 37: 310–314. roenterol Nutr 1987; 6: 517–524. 22. Ratnam S. Etiologic role of Hafnia alvei in human diarrheal illness. Infect Immun 1991; 59: 4744–4745.

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