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Featured researches published by Djamel Khelef.


Veterinary Parasitology | 2013

Common occurrence of zoonotic pathogen Cryptosporidium meleagridis in broiler chickens and turkeys in Algeria.

Djamel Baroudi; Djamel Khelef; Rachid Goucem; Karim T. Adjou; Haileeyesus Adamu; Hongwei Zhang; Lihua Xiao

Only a small number of birds have been identified by molecular techniques as having Cryptosporidium meleagridis, the third most important species for human cryptosporidiosis. In this study, using PCR-RFLP analysis of the small subunit (SSU) rRNA gene, we examined the ileum of 90 dead chickens from 23 farms and 57 dead turkeys from 16 farms in Algeria for Cryptosporidium spp. C. meleagridis-positive specimens were subtyped by sequence analysis of the 60 kDa glycoprotein gene. Cryptosporidium infection rates were 34% and 44% in chickens and turkeys, respectively, with all positive turkeys (25) and most positive chickens (26/31) having C. meleagridis. All C. meleagridis specimens belonged to a new subtype family. The frequent occurrence of C. meleagridis in chickens and turkeys illustrates the potential for zoonotic transmission of cryptosporidiosis in Algeria.


Journal of The South African Veterinary Association-tydskrif Van Die Suid-afrikaanse Veterinere Vereniging | 2013

Subclinical mastitis in cattle in Algeria: Frequency of occurrence and bacteriological isolates

Radhwane Saidi; Djamel Khelef; Rachid Kaidi

The present study was carried out to determine the prevalence of subclinical mastitis in cattle in eighteen herds in the center region of Algeria. Milk samples were collected from 560 quarters of 140 cows free of clinical mastitis. The samples were subjected to California Mastitis Test (CMT) and the positive samples were analysed by bacteriological culture and Speed Mam® Color. The overall quarter prevalence was 28.77% whilst animal prevalence was 28.57%.Bacteriological analysis showed that there was a wide range of bacteria that cause these infections. Staphylococcus aureus (40%) was found to be the most prevalent organism followed by Streptococcus spp. (12.5%), Enterobacteriaceae (2.5%), Pseudomonas spp. (2.5%), Staphylococcus aureus + Streptococcus spp. (12.5%), Streptococcus spp.+ Escherichia coli (7.5%), S. aureus + Mycoplasma spp.(7.5%), and S. aureus +Streptococcus spp.+ E. coli (5%).


Kafkas Universitesi Veteriner Fakultesi Dergisi | 2015

Antibiotic susceptibility and molecular identification of antibiotic resistance genes of staphylococci isolated from bovine mastitis in Algeria.

Radhwane Saidi; Z. Canteki̇n; Djamel Khelef; Yaşar Ergün; Hasan Solmaz; Rachid Kaidi

OBJECTIVEnTo evaluate the diagnostic accuracy of GeneXpert assay for the detection of rifampicin resistance in mycobacterium tuberculosis using conventional drug susceptibility testing as gold standard.nnnMETHODSnThis cross-sectional study was conducted at Jinnah Hospital, Lahore, / Allama Iqbal Medical College, Lahore, Pakistan, from January 2012 to December 2014, and comprised clinically and radiologically diagnosed tuberculosis suspected cases. Pulmonary and extra-pulmonary specimens were collected from strong tuberculosis suspects. All specimens were processed for Ziehl Neelsen staining, Lowenstein-Jensen culture and GeneXpert assay. All mycobacterium tuberculosis positive cases on Lowenstein-Jensen culture were further processed for drug susceptibility testing.nnnRESULTSnOf the 2,200 cases, 840(49.46%) were positive for mycobacterium tuberculosis on GeneXpert assay. Of them, 134(15.6%) cases showed rifampicin resistance on GeneXpert assay. The sensitivity, specificity, positive predictive value and negative predictive value of GeneXpert assay for rifampicin resistance were 127(98.3%), 704(99.1%), 127(94.7%) and 704(99.4%), respectively, by comparing the results with drug susceptibility testing.nnnCONCLUSIONSnGeneXpert assay was an extremely helpful diagnostic tool for the detection of rifampicin resistance in tuberculosis suspects with fairly high sensitivity and specificity along with short turnout time.ARTICLE INFO Food contaminated with multiple antibiotic-resistant S. aureus can be a major threat to the public health. The purpose of this study was to isolate S. aureus from different food sources, determine their antimicrobial susceptibility as well as detection of mecA gene among some resistant isolates. Out of 125 from food of animal origin samples, 19 S. aureus isolates were recovered, and the antimicrobial susceptibility testing showed a high resistance against kanamycin, penicillin G, oxacillin, erythromycin and tetracycline. All the tested isolates were multiple drug resistant (MDR). Eight out of 19 (15.2%) isolates were phenotypically resistant to oxacillin as well as they were carriers for mecA gene. Article history:The study aimed to investigate the phenotypic and genotypic identification of in vitro antimicrobial susceptibility of 21 Staphylococci (10 Staphylococcus aureus and 11 Coagulase Negative Staphylococci) isolated from bovine mastitis to 12 antimicrobial drugs frequently using in veterinary medicine in Algeria. Isolates of staphylococci from bovine mastitis were tested for antibiotics with disc-diffusion method according to the National Committee for Clinical Laboratory Standards guidelines in the Mueller-Hinton agar, and resistant genes mecA, blaZ, aac-aph, ermA, ermC, tetK and tetM were detected by PCR. Staphylococci isolates showed high resistance to penicillin (95.23%), oxacillin (80.95%), clindamycine (80.95%), and erythromycin (76.19%) but, no resistance in all these strains was detected for gentamicin. Among 21 isolates of Staphylococci, 20 were found to be methicillin and multidrug resistant. Multidrug resistant strains exhibited several antibiogram patterns (antibiotic I to XIII). The distribution of antibiotic-resistant genes was mecA (100%) and tetM (100) followed by blaZ (42.85%). In the present study, the significant determination was the high prevalence of methicillin-resistant Staphylococci, which were resistant to multiple antibiotics. The finding of methicillin-resistant staphylococci from bovine mastitis is the first report in Algeria and revealed the status of resistant isolates in herd that might be helpful in treatment, controlling of resistant strains and for deciding culling of cows.


Onderstepoort Journal of Veterinary Research | 2017

Seroprevalence and risk factors for Coxiella burnetii , the causative agent of Q fever in the dromedary camel ( Camelus dromedarius ) population in Algeria

Mohammed Hocine Benaissa; Samir Ansel; Abdallah Mohamed-Cherif; Karima Benfodil; Djamel Khelef; Curtis R. Youngs; Rachid Kaidi; Khatima Ait-Oudhia

Query (Q) fever is a globally distributed zoonotic disease caused by Coxiella burnetii, a bacterial agent for which ruminants are the most prevalent natural reservoir. Data regarding Q fever infection in camels in Algeria are limited. Therefore, a survey to detect seroprevalence of C. burnetii antibodies was conducted among healthy camel populations in a vast area in southeastern Algeria to determine distribution of the Q fever causative organism and to identify risk factors associated with infection. Between January and March 2016, blood samples were collected from 184 camels and serum samples were subsequently analysed using a commercial Enzyme-Linked Immunosorbent Assay (ELISA) kit. At the time of blood collection, a questionnaire investigating 13 potential predisposing factors associated with C. burnetii seropositivity was completed for every dromedary camel and herd. Results were analysed by a chi-square (χ2) test and multivariate logistic regression. The seroprevalence of C. burnetii at the animal level was 71.2% (95% CI: 65.2–78.3) and 85.3% (95% CI: 72.8–97.8) at the herd level. At the animal level, differences in seroprevalence were observed because of herd size, animal age, animal sex, presence of ticks and contact with other herds. A multivariable logistic regression model identified three main risk factors associated with individual seropositivity: (1) age class > 11 years (OR = 8.81, 95% CI: 2.55–30.41), (2) herd size > 50 head (OR = 4.46, 95% CI: 1.01–19.59) and (3) infestation with ticks (OR 2.2; 95% CI: 1.1–4.5). This study of seroprevalence of C. burnetii infection in camels in Algeria revealed a high seroprevalence of Q fever in camel populations in southeastern Algeria and provided strong evidence that Q fever represents an economic, public health and veterinary concern. Appropriate measures should be taken to prevent the spread of C. burnetii and to reduce the risk of Q fever in farm animals and humans in this agro-ecologically and strategically important region of North Africa.


Parasitology Research | 2018

Divergent Cryptosporidium parvum subtype and Enterocytozoon bieneusi genotypes in dromedary camels in Algeria

Djamel Baroudi; Hongwei Zhang; Said Amer; Djamel Khelef; Dawn M. Roellig; Yuanfei Wang; Yaoyu Feng; Lihua Xiao

Little information is available on the occurrence of the zoonotic protists Cryptosporidium spp. and none on Enterocytozoon bieneusi in camels. This preliminary study was conducted to examine the identity of Cryptosporidium subtypes and E. bieneusi genotypes in dromedary camels in Algeria. A total of 39 fecal specimens were collected from young camels. PCR-sequence analysis of the small subunit rRNA was used to detect and genotype Cryptosporidium spp. Cryptosporidium parvum present was further subtyped by sequence analysis of the 60xa0kDa glycoprotein gene. PCR-sequence analysis of the ribosomal internal transcribed spacer gene was used to detect and genotype E. bieneusi. Altogether, two and eight of the specimens analyzed were positive for C. parvum and E. bieneusi, respectively. The former was identified as a new subtype that is genetically related to the C. hominis If subtype family, whereas the latter was identified as two related genotypes (Macaque1 and a novel genotype) in the newly assigned E. bieneusi genotype group 8. Although they are not known hosts for C. parvum and E. bieneusi, camels are apparently infected with genetically distinct variants of these pathogens.


Veterinary Parasitology: Regional Studies and Reports | 2018

Cryptosporidium -associated diarrhoea in neonatal calves in Algeria

Nadia Ouakli; Aouatif Belkhiri; Aida de Lucio; Pamela C. Köster; Mustapha Djoudi; Aness Dadda; Djamel Khelef; Rachid Kaidi; David Carmena

n Abstractn n Neonatal calf diarrhoea triggered by the enteric protozoan parasite Cryptosporidium is a leading cause of morbidity and mortality in calves aged 1-month-old or younger globally. Infected cattle in general and calves in particular have also been demonstrated as major contributors of zoonotic C. parvum oocysts in the environment and have been linked to a number of waterborne outbreaks of human cryptosporidiosis. Little is known on the occurrence, geographical distribution, and molecular diversity of Cryptosporidium infections affecting bovine populations in Algeria. In this study faecal specimens were randomly collected from 460 cattle aged between two days and 18u202fmonths on 10 farms located in the provinces of Aïn Defla, Blida, Sétif, and Tizi Ouzou between the autumn of 2015 and the spring of 2016. Faecal samples were microscopically examined using the modified Ziehl-Neelsen acid-fast technique as screening method. Microscopy-positive samples were confirmed by a commercial coproantigen enzyme-linked immunosorbent assay (Bio-X Diagnostics). The identification of Cryptosporidium species and sub-genotypes in confirmed samples was conducted by PCR and sequence analyses of the small subunit ribosomal RNA (ssu rRNA) and the 60u202fkDa glycoprotein (gp60) genes of the parasite. Overall, 52.2% (240/460) of the investigated cattle tested positive to Cryptosporidium by microscopy. The infection was widespread in all 10 farms surveyed, but was significantly more prevalent in those from Blida in the central part of the country. Bovine cryptosporidiosis affected cattle of all age groups but with different outcomes. Pre-weaned (up to one month old) calves typically presented with diarrhoea, whereas older animals mostly harboured sub-clinical infections. The commercial ELISA used only detected 15.8% (38/240) of the samples that previously tested positive by microscopy, demonstrating a poor performance in field epidemiological surveys. Sequence analysis of the 29 isolates generated at the ssu rRNA loci confirmed the presence of four Cryptosporidium species including C. parvum (72.4%), C. bovis (13.8%), C. andersoni, (3.4%), and C. ryanae (3.4%). Two additional isolates (7.0%) could only be identified at the genus level. Eight out of the 21 isolates assigned to C. parvum were identified as sub-genotype IIaA16G2R1 at the gp60 locus. C. parvum was almost exclusively found infecting pre-weaned calves, whereas C. ryanae and C. andersoni were only detected in asymptomatic animals. Bovine cryptosporidiosis is highly endemic in the surveyed area and represents a veterinary public health concern that should be adequately tackled by Algerian veterinary health authorities and policy makers.n n


Veterinary Parasitology: Regional Studies and Reports | 2017

Molecular characterization of zoonotic pathogens Cryptosporidium spp., Giardia duodenalis and Enterocytozoon bieneusi in calves in Algeria

Djamel Baroudi; Djamel Khelef; Ahcene Hakem; Abdelhafidh Abdelaziz; Xiaohua Chen; Colleen Lysen; Dawn M. Roellig; Lihua Xiao


Revue d'élevage et de médecine vétérinaire des pays tropicaux | 2010

Evaluation d’un test de dépistage précoce des mammites subcliniques des vaches

Radhwane Saidi; Djamel Khelef; Rachid Kaidi


Revue d'élevage et de médecine vétérinaire des pays tropicaux | 2017

Séroprévalence de la fièvre Q chez les bovins de la région de Bejaïa (Algérie)

Salah Agag; Rachid Kaidi; Djamel Khelef


Archive | 2016

Principales zoonoses parasitaires et facteurs de propagations

Khatima Ait-Oudhia; Rachid Triki Yamani; Djamel Khelef

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Lihua Xiao

Centers for Disease Control and Prevention

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Dawn M. Roellig

Centers for Disease Control and Prevention

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Djamel Baroudi

Centers for Disease Control and Prevention

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Hongwei Zhang

Centers for Disease Control and Prevention

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Yaşar Ergün

Mustafa Kemal University

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Colleen Lysen

Centers for Disease Control and Prevention

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Said Amer

Centers for Disease Control and Prevention

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