Risk factors for dairy cows mastitis in Algeria, antibiotic resistance and molecular typing of the causative Staphylococcus aureus.

Adoption of a rational management in dairy farms would improve the milk quality and farmers' income. In the current study, we aimed to describe bovine mastitis in 32 dairy herds, identify the main cow- and herd-associated risk factors, and analyze both epidemiological along with molecular characteristics of Staphylococcus aureus infecting udders. Based on Californian Mastitis Test and clinical examination, the prevalence of mastitis in cows was 52.25% (116/222), of which 6.3% was clinical mastitis and 45.94% was subclinical mastitis. Overall, 218 (24.54%) quarters suffered from mastitis, whose 29.81% (65/218) infected with S. aureus. Mastitis was lowest in mid-lactation with OR = 0.371 with 95% confidence interval (CI) of 0.141-0.976, and in cows separated from their calves (OR = 0.164, 95% CI 0.056-0.477) than suckler cows. Similar results were obtained from S. aureus related mastitis. To assess the genetic lineages of S. aureus isolates, we determined clonal complexes (CC) using DNA microarray hybridization profiles and performed spa typing. The strains were assigned to nine clonal complexes, and 19 spa types; with CC97 (44.77%), and CC22 (40.29%) were the most predominant lineages and t223 (40.29%), t7136 (10.44%), t359 (8.95%) and t267 (5.97%) were the most common spa types. A total of 88.05% (n = 59) isolates were resistant to at least one tested antibiotic while only 4.47% were multi-drug resistant strains. Higher rates of resistance were observed for penicillin (86.5%) and tetracycline (14.9%) respectively. Our results show the need for adoption of feasible mastitis program with special emphasis on sub-clinical mastitis and associated risk factors.

[Perception of doctors in different specialties of iron deficiency and iron deficiency anemia in Algeria in 2016: the SUPFER DZ survey]. / Perception de la carence martiale et de l'anémie ferriprive par les médecins de différentes spécialités en Algérie en 2016: enquête SUPFER DZ.

INTRODUCTION: diagnostic methods and management of iron deficiency and iron deficiency anemia in clinical practice in Algeria is poorly known. METHODS: we conducted a cross-sectional survey among doctors in different specialties treating patients with iron deficiency anemia in 2016. RESULTS: data analysis was based on 349 questionnaires which were validated (anesthesia/resuscitation: 39; obstetrics and gynaecology: 111; oncology/Hematology: 71; hepato-gastroenterology: 64; cardiology: 36; internal medicine: 28). All specialties combined, 73% (254/349) of physicians thought that at least 30% of their patients had iron deficiency anemia; 65% of physicians (226/349) thought that at least 30% of their patients had iron deficiency. Iron deficiency was investigated systematically by 57% (63/111) of physicians of the group obstetrics and gynaecology, but only by 11% (26/238) of the remaining doctors; indeed, 82% (195/238) of physicians investigated it only in patients with anemia. The assessment of iron deficiency showed that the hemoglobin (Hb) was almost always determined (89%; 310/349) while laboratory tests to explore iron metabolism were inadequate: 70% (244/349) of physicians performed serum ferritin test and only 37% (128/349) performed transferrin saturation. Patients with iron deficiency (with or without anemia) received oral iron therapy (prescribed by 92% (322/349) of physicians) and iron injections therapy depending on Hb level (prescribed by 36% (127/349) of physicians). CONCLUSION: this survey shows that iron deficiency is evaluated only in patients with anemia. In particular, laboratory tests to measure iron deficiency are insufficiently prescribed.

Staphylococcus aureus isolated from selected dairies of Algeria: Prevalence and susceptibility to antibiotics.

AIM: The objectives of this study were to assess the prevalence of Staphylococcus aureus in raw milk in Algerian dairies, to study the effect of seasons on the contamination of milk and the susceptibility of isolated strains to antibiotics, and to estimate the risk on the health consumer. MATERIALS AND METHODS: The ISO method 6888-1 (1) was used for Staphylococcus screening. Antimicrobial susceptibility to the 11most used antibiotics in veterinary medicine was assessed using the disk diffusion assay. RESULTS: The overall prevalence was 31.56% (95/301); 34.84% (85/244) from raw milk collectors cisterns (MCC), 22.73% (5/22) from mixing tank milk before pasteurization, and 14.29% (5/35) from pasteurized tank milk (p<0.05). A significant difference (p<0.001) of contamination on MCC was observed between dairies without season influence (p≥0.05). It was observed that 49.47% of S. aureus isolates were resistant to penicillin, 5.26% to tetracycline, 4.21% to erythromycin, 3.15% to neomycin, 2.10% to cefoxitin, 2.10% to clindamycin, and 1.05% to ofloxacin. No resistance was observed for vancomycin, gentamicin, chloramphenicol, and trimethoprim-sulfamethoxazole. CONCLUSION: A high prevalence of S. aureus from MCC was observed without significant effect of season. The pasteurization does not ensure the elimination of bacteria in all samples. Half of the isolates were resistant to penicillin. These findings emphasize the importance of S. aureus control in Algerian milk industry at different levels to improve public health.

New host shift from human to cows within Staphylococcus aureus involved in bovine mastitis and nasal carriage of animal's caretakers.

Staphylococcus aureus is a commensal and pathogen of both humans and bovines. While the epidemiology of both groups has been extensively studied individually, little is known about the potential zoonotic transfer from animal strains to human being and vice versa. To determine the S. aureus prevalence of bovine mastitis in Algeria and the zoonotic transfer of strains to human beings, mastitis milk samples were collected, and professionals in a close contact with bovines were nasal swabbed. S. aureus isolates were all characterized by methicillin resistance and spa-typing. DNA microarrays analysis was performed on a subset of strains in order to detect other virulence factors, including toxins, and to assign the isolates to theirs MLST clonal complexes. Overall, 116/222 (52.3%) cows suffered from mastitis, whose 38.8% (45/116) infected with S. aureus. Human nasal carriage was of 38% (49/129), with only 4 MRSA carriers (3.1%). A higher diversity of spa-types was observed in human (35/50) than in bovine (18/67) isolates, with a predominance of clonal complexes CC97 and CC22 in bovines. The typical animal clone CC97 was occasionally detected in human beings. Conversely, the CC22 S. aureus clone largely switched from humans to bovines. Our study highlights the potential dynamics of animal and human S. aureus strains in the farm environment in Algeria, which may represent a health threat in both populations.

High levels of Staphylococcus aureus and MRSA carriage in healthy population of Algiers revealed by additional enrichment and multisite screening.

The purpose of the research is to characterize Staphylococcus aureus colonization in healthy population of Algiers, to assess the impact on diagnostic performance of systematic additional broth enrichment, and to ascertain the additional benefits of multiple site screening. In order to more accurately determine the prevalence of S. aureus colonization, the swab specimens from multiple screening sites were incubated in brain-heart broth before agar plating. From 2009 to 2011, 1176 samples were collected from 459 participants (201 adults and 258 children). The additional enrichment detection step significantly increased S. aureus detection rates (p < 0.0001). S. aureus nasal detection was positive in 37.8% of adults, and the addition of throat samplings significantly increased the S. aureus detection rate up to 54.7% (p < 0.001). S. aureus nasal detection was positive in 37.6% of children. The addition of throat samplings in children significantly increased the S. aureus detection rate up to 53.1% (p < 0.001) and that of anal samplings up to 59.7%. The overall prevalence of methicillin-resistant S. aureus was 5.2% (3% of adults and 7% of children). spa typing of all isolates revealed a diverse but strongly clonal S. aureus population structure. This approach involving multiple anatomical sampling sites and an additional enrichment of the swabs before conventional culture significantly increases the detection rate of S. aureus carriers and may prove valuable to improve global S. aureus infection prevention.

Multicentric study in five African countries of antibiotic susceptibility for three main pathogens: Streptococcus pneumoniae, Staphylococcus aureus, and Pseudomonas aeruginosa.

Antibiotic resistance is a growing clinical and epidemiological problem. We report on the antibiotic susceptibility of three pathogens isolated from patients in Algeria, Egypt, Morocco, Senegal, and Tunisia during 2010-2011. In total, 218 Streptococcus pneumoniae, 428 Staphylococcus aureus, and 414 Pseudomonas aeruginosa strains were collected. S. pneumoniae resistance was noted against penicillin (30.2%), erythromycin (27.4%), cefpodoxime (19.1%), amoxicillin (12.0%), cefotaxime (7.4%), and levofloxacin (3.2%). All the strains were teicoplanin susceptible. Staphylococcus aureus methicillin resistance differed between countries, from 5.0% in Senegal to 62.7% in Egypt. Levofloxacin resistance was low in all countries, and the highest rate (in Egypt) was still only 13.6% for intermediate and resistant strains combined. Most strains were susceptible to fosfomycin (99.3%) and pristinamycin (94.2%). P. aeruginosa resistance was found against levofloxacin (30.4%), ciprofloxacin (29.9%), tobramycin (19.7%), ceftazidime (19.2%), and imipenem (17.9%), but not colistin. Antibiotic susceptibility varied widely between countries, with resistance typically most prevalent in Egypt.

High-Level Primary Clarithromycin Resistance of Helicobacter pylori in Algiers, Algeria: A Prospective Multicenter Molecular Study.

Knowledge of local antibiotic resistance is crucial to adaptation for the choice of the optimal first-line treatment for Helicobacter pylori infection. Clarithromycin is a key component of the standard triple therapy largely used worldwide and, more particularly, in Algeria. Clarithromycin resistance is the main risk factor for treatment failure. The aim of this study was to evaluate, for the first time in Algeria, the prevalence of the primary resistance of H. pylori to clarithromycin. We conducted a prospective study (2008-2014) that included 195 Algerian patients referred for gastroduodenal endoscopy to two University Hospitals, one General Hospital, and several private gastroenterologists in Algiers (Algeria). One gastric biopsy was collected for the molecular detection of H. pylori and the mutations in 23S rRNA genes that confer resistance to clarithromycin with a quadruplex real-time PCR using Scorpion primers. The Scorpion PCR detected H. pylori DNA in 91 biopsies (47%). A mutation conferring resistance to clarithromycin was detected in 32 of the 91 positive patients (35%) and in 29 of the 88 positive patients never previously treated for an H. pylori infection (33%). The prevalence of primary resistance of H. pylori to clarithromycin was 33% in the Algerian population being studied. The high level of primary clarithromycin resistance in the H. pylori strains infecting the Algerian population that we report leads us to recommend the abandonment of the standard clarithromycin-based triple therapy as a first-line treatment in Algeria.

IgG4 subclass-specific responses to Staphylococcus aureus antigens shed new light on host-pathogen interaction.

IgG4 responses are considered indicative for long-term or repeated exposure to particular antigens. Therefore, studying IgG4-specific antibody responses against Staphylococcus aureus might generate new insights into the respective host-pathogen interactions and the microbial virulence factors involved. Using a bead-based flow cytometry assay, we determined total IgG (IgGt), IgG1, and IgG4 antibody responses to 40 different S. aureus virulence factors in sera from healthy persistent nasal carriers, healthy persistent noncarriers, and patients with various staphylococcal infections from three distinct countries. IgGt responses were detected against all tested antigens. These were mostly IgG1 responses. In contrast, IgG4 antibodies were detected to alpha-toxin, chemotaxis inhibitory protein of S. aureus (CHIPS), exfoliative toxins A and B (ETA and -B), HlgB, IsdA, LukD, -E, -F, and -S, staphylococcal complement inhibitor (SCIN), staphylococcal enterotoxin C (SEC), staphylococcal superantigen-like proteins 1, 3, 5, and 9 (SSL1, -3, -5, and -9), and toxic shock syndrome toxin 1 (TSST-1) only. Large interpatient variability was observed, and the type of infection or geographical location did not reveal conserved patterns of response. As persistent S. aureus carriers trended toward IgG4 responses to a larger number of antigens than persistent noncarriers, we also investigated sera from patients with epidermolysis bullosa (EB), a genetic blistering disease associated with high S. aureus carriage rates. EB patients responded immunologically to significantly more antigens than noncarriers and trended toward even more responses than carriers. Altogether, we conclude that the IgG4 responses against a restricted panel of staphylococcal antigens consisting primarily of immune modulators and particular toxins indicate important roles for these virulence factors in staphylococcal pathogen-host interactions, such as chronicity of colonization and/or (subclinical) infections.

Role of SHV ß-lactamase variants in resistance of clinical Klebsiella pneumoniae strains to ß-lactams in an Algerian hospital.

Three clinical Klebsiella pneumoniae strains, KpARG74, KpARG220 and KpARG185, isolated from a hospital in Algeria, carried the novel ß-lactamases SHV-98, SHV-99 and SHV-100, respectively, and co-expressed TEM-1 and either CTX-M-3 or CTX-M-15. In contrast, transformed cells possessing the genes for these novel ß-lactamases, i.e. EcDH5α-SHV-98, EcDH5α-SHV-99 and EcDH5α-SHV-100, respectively, carried unique sequence features of bla(SHV) gene variants, enabling oxyimino-cephalosporin susceptibility and confirming that none of the transformants exhibited extended-spectrum ß-lactamase (ESBL) properties. SHV-100 is apparently functional, despite differing from the SHV-1 sequence by duplication of 13 amino acids. The SHV-99 enzyme differed from the parental SHV-1 by the amino acid substitution Asp104→Gly, which is an important position in the development of the ESBL phenotype in TEM ß-lactamases. This is the first time, to our knowledge, that this mutation has been reported in clinically occurring isolates. Thus, kinetic characterization of the SHV-99 enzyme was performed. The SHV-99 enzyme showed higher affinity (K(m) of 196 µM), catalytic activity (k(cat) of 0.5 s⁻¹) and catalytic efficiency (k(cat)/K(m) of 0.003 µM⁻¹ s⁻¹) than SHV-1 ß-lactamase against aztreonam. These results showed that the neutral glycine at residue 104 increased the affinity of the enzyme to aztreonam, but was unable to develop the ESBL phenotype in SHV enzymes. As the emergence of new threatening combinations of resistance determinants among nosocomial pathogens is further possible, this study has highlighted the need to reverse the spread of initial mutations.

Rapid detection of Staphylococcus aureus Panton-Valentine leukocidin in clinical specimens by enzyme-linked immunosorbent assay and immunochromatographic tests.

Staphylococcus aureus strains producing Panton-Valentine leukocidin (PVL) have been epidemiologically linked to specific human infections. To evaluate immunological tests that may be used to diagnose infections with PVL-producing strains, we prospectively collected pus, respiratory tract specimens, and joint fluid specimens from which S. aureus had been isolated in clinical laboratories in six countries. An enzyme-linked immunosorbent assay (ELISA) and an immunochromatographic test (ICT) targeting LukS-PV were performed directly with clinical samples for the detection of PVL. The same tests were applied to S. aureus culture supernatants. The corresponding S. aureus isolates were characterized by PCR for the presence of the PVL locus (lukS-PV and lukF-PV) and the mecA gene. A total of 185 samples from 144 skin infections, 23 bone and joint infections, and 18 lower respiratory tract infections were analyzed. By PCR, 72/185 S. aureus isolates were PVL locus positive (PVL(+)); 28 of these were also mecA positive. PVL was detected in the supernatants of all PVL(+) strains by both ELISA and an ICT, while no signal was observed with PVL-negative strains. The PVL concentrations in human clinical samples that grew PVL(+) strains ranged from 0 to 399 microg/ml by ELISA. By the use of 0.015 microg/ml of PVL as a cutoff value, PVL was detected in 65/72 (90%) of the clinical samples by ELISA. The sensitivity and specificity of the ELISA test were 90% and 100%, respectively. By the ICT, PVL was detected in 57/72 (79%) of the samples, and the sensitivity and specificity of ICT were 79% and 100%, respectively. PVL is expressed by S. aureus during human infection, and a PVL-specific ELISA and ICT could be reliable tests for the diagnosis of infections caused by PVL-producing strains.

Immunogenicity of toxins during Staphylococcus aureus infection.

BACKGROUND: Toxins are important Staphylococcus aureus virulence factors, but little is known about their immunogenicity during infection. Here, additional insight is generated. METHODS: Serum samples from 206 S. aureus-infected patients and 201 hospital-admitted control subjects were analyzed for immunoglobulin (Ig) G binding to 20 toxins, using flow-cytometry based technology. Antibody levels were associated with polymerase chain reaction-defined presence of toxin genes in homologous S. aureus isolates. RESULTS: IgG levels directed to exfoliative toxin (ET) A, ETB, gamma hemolysin B (HlgB), leukocidin (Luk) D, LukE, LukS, staphylococcal enterotoxin (SE) A, SEE, SEH, SEI, and SElM were higher in S. aureus-infected patients than in control subjects (P < .05). Furthermore, in the S. aureus-infected patient group, IgG levels were higher if genes encoding ETA, ETB, SEA, SEC, SEH, SElQ, toxic shock syndrome toxin-1 (TSST-1), or Panton-Valentine leukocidin (PVL) were present in the infectious isolate (P< .05). Levels of anti-SEA IgG increased during infections with sea-positive (median fluorescence intensity from 11,555 to 12,388; P<.05) but not sea-negative strains. In addition, anti-LukS IgG levels increased during skin and soft-tissue infections with luk-PV-positive (median fluorescence intensity from 15,231 to 15,911; P<.05) but not luk-PV-negative strains. Bacteremia was associated with sea (odds ratio, 3.4; 95% confidence interval, 1.2-10.0) and tst (odds ratio, 5.7; 95% confidence interval, 1.6-20.8). Skin and soft-tissue infections and bone and joint infections were associated with luk-PV (odds ratio, 2.5; 95% confidence interval, 1.2-5.2). CONCLUSIONS: Many toxins are expressed in vivo and recognized by the immune system during staphylococcal infections, suggesting their involvement in S. aureus pathogenesis.

Dissemination of ESBL and Qnr determinants in Enterobacter cloacae in Algeria.

OBJECTIVES: The aim of this study is to evaluate the prevalence and diversity of extended-spectrum beta-lactamases (ESBLs) in Enterobacter cloacae clinical isolates collected from Algerian hospitals and to verify the association with qnr genes. METHODS: MICs were determined by Etest for isolates giving positive double-disc synergy tests, and all isolates were screened by PCR and sequenced, respectively, for bla(TEM), bla(CTX-M), bla(SHV) and bla(VEB) genes and for qnr genes (qnrA, qnrB, qnrS), using specific primers. RESULTS: The prevalence of ESBLs was 25/141 (17.7%) with 11, 9, 4 and 1 isolates testing positive for genes encoding CTX-M-15, CTX-M-3, SHV-12 and VEB-1, respectively. Two SHV-12 producers and one CTX-M-15 producer expressed QnrS1, one isolate produced CTX-M-15 and QnrB1 and one SHV-12 producer co-expressed QnrS1 and QnrB4. qnrA was not detected in our collection, and qnr alleles were not detected in non-ESBL-producing isolates. CONCLUSIONS: SHV-12, QnrS1, QnrB1 and QnrB4 were reported for the first time in Algeria. This study also described a co-expression of qnrS1 and qnrB4 by an SHV-12 producer isolate.

CTX-M-3 and CTX-M-15 extended-spectrum beta-lactamases in isolates of Escherichia coli from a hospital in Algiers, Algeria.

Sixteen strains of Escherichia coli isolated between January and June 2005 in a hospital in Algiers carry the ISEcp1 element and the TEM and either CTX-M-3 (n=3) or CTX-M-15 (n=13) beta-lactamases. Fourteen of the isolates are multidrug resistant. Five isolates from the neonatal ward were indistinguishable by pulsed-field gel electrophoresis.

Detection of methicillin-resistant Staphylococcus aureus strains resistant to multiple antibiotics and carrying the Panton-Valentine leukocidin genes in an Algiers hospital.

Forty-five Panton-Valentine leukocidin (PVL)-positive, methicillin-resistant Staphylococcus aureus strains were isolated in Algeria between 2003 and 2004; 18 isolates were isolated in the community and 27 in a hospital. Five PVL-positive hospital isolates were resistant to multiple antibiotics, including ofloxacin and gentamicin for three isolates.

Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae isolated in Algiers, Algeria.

There are few data on antibiotic resistance of Streptococcus pneumoniae in Algeria. Among 309 strains, 34.6% were penicillin G-nonsusceptible S. pneumoniae strains (25.2% were intermediate and 9.4% were resistant). Serotypes 1, 5, 14, and 6 were the most frequent in invasive child infections. A multicenter study to standardize the national guidelines is needed.