Antimicrobial resistance of bacterial agents of the upper respiratory tract of school children in Buea, Cameroon

Trends of Antibacterial Resistance at the National Reference Laboratory in Cameroon: Comparison of the Situation between 2010 and 2017

Introduction

Antimicrobial resistance represents a growing public health threat. One of the World Health Organization's strategic objectives is “strengthening knowledge through surveillance and research.” Sub-Saharan African countries are still far from achieving this objective. We aimed to estimate and compare the prevalence of antibacterial resistance in 2010 and 2017 in Cameroon.

Methods

We conducted a retrospective study on all clinical specimens cultured in Centre Pasteur du Cameroun (CPC) in 2010 and 2017. Data were extracted from the CPC's laboratory data information system software and then managed and analyzed using R. Bacterial resistance rates were calculated in each year and compared using chi-square or Fisher's tests, and relative changes were calculated. Outcomes included acquired resistance (AR), WHO priority resistant pathogens, some specific resistances of clinical interest, and resistance patterns (multi, extensively, and pan drug resistances) for five selected pathogens.

Results

A total of 10,218 isolates were analyzed. The overall AR rate was 96.0% (95% CI: 95.4–96.6). Most of WHO priority bacterial resistance rates increased from 2010 to 2017. The most marked increases expressed as relative changes concerned imipenem-resistant Acinetobacter (6.2% vs. 21.6%, +248.4%, p = 0.02), imipenem-resistant Pseudomonas aeruginosa (13.5% vs. 23.5%, +74.1%, p < 0.01), 3rd generation-resistant Enterobacteriaceae (23.8% vs. 40.4%, +65.8%, p < 10⁻¹⁵), methicillin-resistant Staphylococcus aureus (27.3% vs. 46.0%, +68.6%, p < 0.002), fluoroquinolone-resistant Salmonella (3.9% vs. 9.5%, +142.9%, p = 0.03), and fluoroquinolone-resistant Enterobacteriaceae (32.6% vs. 54.0%, +65.8%, p < 10⁻¹⁵). For selected pathogens, global multidrug resistance was high in 2010 and 2017 (74.9% vs. 78.0% +4.1%, p = 0.01), intensively drug resistance rate was 5.8% (7.0% vs. 4.7%; p = 0.07), and no pan drug resistance has been identified.

Conclusion

Bacterial resistance to antibiotics of clinical relevance in Cameroon was high and appeared to increase between 2010 and 2017. There is a need for regular surveillance of antibacterial resistance to inform public health strategies and empirically inform prescription practices.

Antimicrobial resistance from a one health perspective in Cameroon: a systematic review and meta-analysis

Background

Antimicrobial resistance (AMR) is widely acknowledged as a global health problem, yet in many parts of the world its magnitude is not well elucidated. A baseline assessment of the AMR prevalence is a priority for implementation of laboratory-based AMR surveillance This review, focused on a One health approach, aimed at describing the current status of AMR in Cameroon.

Methods

PubMed, Google Scholar and African Journals Online databases were searched for articles published in English and French in accordance with the PRISMA guidelines. Retrieval and screening of article was done using a structured search string with strict inclusion/exclusion criteria. Free-text and grey literature were obtained by contacting the authors directly. The pooled prevalence and 95% confidence intervals were calculated for each pathogen–antibiotic pairs using random-effects models.

Result

Amongst 97 full-text articles reviewed, 66 met the eligibility criteria. The studies originated from the Centre (24; 36.4%), South-West (16; 24.2%), West (13; 19.7%), Littoral (9; 13.6%) and other (4; 6.1%) regions of Cameroon. These studies reported AMR in human (45; 68.2%), animals (9; 13.6%) and the environment (12; 18.2%). Overall, 19 species of bacteria were tested against 48 antibiotics. These organisms were resistant to all classes of antibiotics and showed high levels of multidrug resistance. Escherichia coli, Klebsiella pneumoniae and Staphylococcus spp were reported in 23, 19 and 18 of the human studies and revealed multidrug resistance (MDR) rates of 47.1% [95% CI (37.3–57.2%)], 51.0% [95% CI (42.0–59.9)] and 45.2% [95% CI (38.0–54.7)], respectively. Salmonella spp was reported in 6 of the animal studies and showed a MDR rate of 46.2% [95% CI (39.2–53.5%)] while Staphylococcus spp in 8 of environment studies showed MDR rate of 67.1% [95% CI (55.2–77.2%)].

Conclusion

This review shows that resistance to commonly prescribed antibiotics in Cameroon is high. The findings emphasize the urgent need to address gaps in the standardization of AMR diagnostics, reporting and use of available information to optimize treatment guidelines for the arsenal of antibiotics. Effective AMR surveillance through continued data sharing, large-scale collaboration, and coordination of all stakeholders is essential to understand and manage the AMR national burden.

Pharyngeal colonization and drug resistance profiles of Morraxella catarrrhalis, Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae among HIV infected children attending ART Clinic of Felegehiwot Referral Hospital, Ethiopia

Background

Asymptomatic pharyngeal colonization by potential bacteria is the primary reservoir for bacterial species within a population and is considered a prerequisite for development of major childhood diseases such as sinusitis, otitis media, pneumonia, bacteremia, and meningitis. However, there is dearth of data on the colonization and drug resistance pattern of the main bacterial pathogens in the pharynx of HIV infected children in Ethiopia. Therefore, this study determined the pharyngeal colonization and drug resistance profile of bacterial pathogens in HIV infected children attending ART clinic of Felegehiwot Referral Hospital (FHRH), Amhara Region, Ethiopia.

Methods

A hospital based cross-sectional study was conducted from May 2016 to June 2017 at the ART clinic of FHRH. A total of 300 HIV infected children were enrolled in the study. Data on socio-demographic characteristics of the study participants were collected with face-to-face interview and patient—card review using structured questionnaire. Bacterial species were identified using standard bacteriological techniques. Drug susceptibility testing was performed using disk diffusion technique. Chi-square test was done to determine associations among variables.

Results

The median age of the participants was 11 years. Overall, 153 (51%) of children were colonized by respiratory bacteria in their pharynx. Colonization rate was higher in children from mothers who had attained college and above levels of education than others (P = 0.04). It was also higher in children without the sign of malnutrition than others (P = 0.004). The colonization rate of S.aureus, M.catarrhalis, S.pneumoniae and H.influenzae were 88 (29%), 37 (12.3%), 31 (10.3%) and 6 (2%), respectively. S.aureus—M.catarrhalis concurrent colonization was found in 14 (4.7%) of children. Age (P = 0.03), schooling (P = 0.045) and history of running nose (P = 0.043) were significantly associated with S.aureus colonization. Living in urban setting (P = 0.042) and children from mothers with college and above levels of education (P = 0.002) were significantly associated with M.catarrhalis colonization. Majority of the isolates were resistant to penicillin (68.5%) and cotrimoxazole (52.5%).S.aureus isolates were resistant to penicillin (84.1%) and cotrimoxazole (51.1%).M.catarrhalis isolates were resistant to penicillin (94.6%), erythromycin (86.5%)and cotrimoxazole (78.4%). Overall, 99 (59.3%) of the isolates were multi-drug (MDR) resistant. The overall MDR rates among S.aureus, M.catarrhalis and S.pneumoniae isolates were 65.9%, 78.4% and 22.6%, respectively.

Conclusions

Pharyngeal colonization of respiratory bacteria in HIV infected children is a major public health problem. Single and multiple antibiotic resistant is alarmingly high among respiratory colonizers. Therefore, regular screening of HIV infected children for culture and antimicrobial susceptibility testing is recommended to prevent the development of severe opportunistic infections.

Burden of bacterial upper respiratory tract pathogens in school children of Nepal

INTRODUCTION

Respiratory tract infections are one of the most common human infections in all age group and important cause of mortality and morbidity worldwide. Most bacterial upper respiratory tract infections are vaccine preventable. This study aimed to determine the prevalence of carrier state of bacterial upper respiratory tract pathogens among school children. It also aimed to study their antibiograms.

METHODS

The specimen from posterior pharyngeal wall and tonsils were collected from 204 participants on calcium alginate coated swabs (HiMedia). Isolates were identified by standard microbiological methods and tested for in vitro antibiotic susceptibility testing by modified Kirby-Bauer disc diffusion method.

RESULTS

In this study, Streptococcus pneumoniae (16.6%) was the most common bacterial pathogen recovered, followed by Staphylococcus aureus (14.7%), β-haemolytic streptococci (non-Group A) (8.8%), Streptococcus pyogenes (5.3%) and Corynebacterium diphtheriae (3.4%). The Gram negative bacteria were Klebsiella pneumoniae (4.9%), Haemophilus influenzae (3.4%) and Neisseria meningitidis (1.4%). Important findings in antibiogram include high resistance of Streptococcus pneumoniae to penicillin (91.17%) and resistance of S. aureus to oxacillin (23.3%).

CONCLUSION

Pharyngeal colonisation by S. pneumoniae was found high among school children and this calls for an urgent need to include pneumococcal vaccine in routine national immunisation schedule of Nepal given the high burden of invasive pneumococcal disease. Despite expected universal vaccination, pharyngeal colonisation by C. diphtheriae is possible and there is possibility of transmission of these respiratory pathogens to other healthy children.

Short-term increase in prevalence of nasopharyngeal carriage of macrolide-resistant Staphylococcus aureus following mass drug administration with azithromycin for trachoma control

Background

Mass drug administration (MDA) with azithromycin is a corner-stone of trachoma control however it may drive the emergence of antimicrobial resistance. In a cluster-randomized trial (Clinical trial gov NCT00792922), we compared the reduction in the prevalence of active trachoma in communities that received three annual rounds of MDA to that in communities that received a single treatment round. We used the framework of this trial to carry out an opportunistic study to investigate if the increased rounds of treatment resulted in increased prevalence of nasopharyngeal carriage of macrolide-resistant Staphylococcus aureus. Three cross-sectional surveys were conducted in two villages receiving three annual rounds of MDA (3 × treatment arm). Surveys were conducted immediately before the third round of MDA (CSS-1) and at one (CSS-2) and six (CSS-3) months after MDA. The final survey also included six villages that had received only one round of MDA 30 months previously (1 × treatment arm).

Results

In the 3 × treatment arm, a short-term increase in prevalence of S. aureus carriage was seen following MDA from 24.6% at CSS-1 to 38.6% at CSS-2 (p < 0.001). Prevalence fell to 8.8% at CSS-3 (p < 0.001). A transient increase was also seen in prevalence of carriage of azithromycin resistant (Azm^R) strains from 8.9% at CSS-1 to 34.1% (p < 0.001) in CSS-2 and down to 7.3% (p = 0.417) in CSS-3. A similar trend was observed for prevalence of carriage of macrolide-inducible-clindamycin resistant (iMLS_B) strains. In CSS-3, prevalence of carriage of resistant strains was higher in the 3 × treatment arm than in the 1 × treatment (Azm^R 7.3% vs. 1.6%, p = 0.010; iMLS_B 5.8% vs. 0.8%, p < 0.001). Macrolide resistance was attributed to the presence of msr and erm genes.

Conclusions

Three annual rounds of MDA with azithromycin were associated with a short-term increase in both the prevalence of nasopharyngeal carriage of S. aureus and prevalence of carriage of Azm^R and iMLS_BS. aureus.

Trial registration

This study was ancillary to the Partnership for the Rapid Elimination of Trachoma, ClinicalTrials.gov NCT00792922, registration date November 17, 2008.

Isolation of antimicrobial resistant bacteria in upper respiratory tract infections of patients

Haemophilus influenzae, Streptococcus pyogenes, Moraxella catarrhalis, Staphylococcus aureus, and Streptococcus pneumoniae are usual cause of upper respiratory tract infection cases. The present study aims the isolation of bacterial strains which are resistant to the commonly prescribed antibiotics. In total, 900 throat swabs were obtained from the patients suffering from upper respiratory tract infections residing in three different localities. The maximum number of isolates (64 %) were obtained from locality-1 (L-1), whereas lowest isolates were found in second locality (L-2). H. influenzae was found to be the most dominant bacterial pathogen in upper respiratory tract infections in patients with 42 % of the total isolates. H. influenzae and Chlamydia pneumoniae were resistant to β-lactam antibiotics but susceptible to fluroquinolones and aminoglycosides, whereas S. aureus and S. pneumoniae were found to be highly resistant to β-lactam, aminoglycosides and fluroquinolones. S. aureus was also moderately resistant to fluroquinolones and aminoglycosides with percent resistance of 26, 33 and 18 %, respectively. 56 % S. pneumoniae isolates were resistant against erythromycin, 27 % against chloramphenicol and 23 % against cefuroxime. The studies revealed that S. aureus and S. pneumoniae strains were high producer of biofilms which could be one of the reasons for their high pathogenicity.

Bacteria Etiological Agents Causing Lower Respiratory Tract Infections and Their Resistance Patterns

Background:

Lower respiratory tract infections (LTRIs) are among the most common infectious diseases with potential life-threatening complications.

Methods:

The study consisted of 426 patients with suspected LTRIs from mid and far western region of Nepal between September 2011 and July 2014. The specimens were collected and processed according to the standard microbiological methods at the Central Laboratory of Microbiology of Nepalgunj Medical College, Nepal.

Results:

Among the isolated Gram-positive organisms, Streptococcus pneumonia (n = 30, 51.7%) was the most predominant pathogen, followed by Staphylococcus aureus (n = 28, 48.3%). Among the isolated Gram-negative organisms, Pseudomonas aeruginosa (n = 71, 35.32%) was the most predominant pathogen, followed by Haemophilus influenzae (n = 68, 33.83%), Klebsiella pneumonia (n = 36, 17.19%), and Escherichia coli (n = 26, 12.94%). The pattern of resistance varied regarding the bacteria species, and there were multi-resistant isolates. Also, a significant difference (P < 0.05) was observed between males and females for each type of bacterial species. Among 259 isolates, 86 (33.20%) were from children aged 1-10 years, which were statistically significant (P < 0.05) compared to the other age groups.

Conclusions:

P. aeruginosa and H. influenzae (Gram-negative) and S. pnemoniae (Gram-positive) were the most common bacterial isolates recovered from LTRIs. Age group of 1-10 years old was at a higher risk. Many isolates showed appreciable levels of antibiotic resistance due to antibiotic abuse. There is a need to increase surveillance and develop better strategies to curb the increasing prevalence of LRTI in this region of Nepal.

Pneumococcal carriage in sub-Saharan Africa--a systematic review

BACKGROUND

Pneumococcal epidemiology varies geographically and few data are available from the African continent. We assess pneumococcal carriage from studies conducted in sub-Saharan Africa (sSA) before and after the pneumococcal conjugate vaccine (PCV) era.

METHODS

A search for pneumococcal carriage studies published before 2012 was conducted to describe carriage in sSA. The review also describes pneumococcal serotypes and assesses the impact of vaccination on carriage in this region.

RESULTS

Fifty-seven studies were included in this review with the majority (40.3%) from South Africa. There was considerable variability in the prevalence of carriage between studies (I-squared statistic = 99%). Carriage was higher in children and decreased with increasing age, 63.2% (95% CI: 55.6-70.8) in children less than 5 years, 42.6% (95% CI: 29.9-55.4) in children 5-15 years and 28.0% (95% CI: 19.0-37.0) in adults older than 15 years. There was no difference in the prevalence of carriage between males and females in 9/11 studies. Serotypes 19F, 6B, 6A, 14 and 23F were the five most common isolates. A meta-analysis of four randomized trials of PCV vaccination in children aged 9-24 months showed that carriage of vaccine type (VT) serotypes decreased with PCV vaccination; however, overall carriage remained the same because of a concomitant increase in non-vaccine type (NVT) serotypes.

CONCLUSION

Pneumococcal carriage is generally high in the African continent, particularly in young children. The five most common serotypes in sSA are among the top seven serotypes that cause invasive pneumococcal disease in children globally. These serotypes are covered by the two PCVs recommended for routine childhood immunization by the WHO. The distribution of serotypes found in the nasopharynx is altered by PCV vaccination.