Two-year surveillance of antibiotic resistance in Streptococcus pneumoniae in four African cities

Serotype distribution and antimicrobial susceptibility of invasive Streptococcus pneumoniae isolates among adult and elderly population before and after introduction of pneumococcal conjugate vaccine in Casablanca, Morocco

BACKGROUND

Streptococcus pneumoniae (S. pneumoniae), remains a major cause of mortality and morbidity worldwide. The objective of this study was to determine the trends of invasive pneumococcal diseases (IPD) in adult and elderly population in Casablanca (Morocco) before and after introduction of pneumococcal conjugate vaccine (PCV) by determining the distribution of pneumococcal serotypes and antibiotic resistance profile of isolated strains.

METHOD

The proposed study is a retrospective laboratory-based surveillance of IPD in hospitalized adult (15-59 years old) and elderly (≥ 60 years old) patients in Ibn Rochd University Hospital Centre from 2007 to 2019 (13 years). All the 250 non-duplicate clinical invasive isolates from adult and elderly patients, confirmed as S. pneumoniae according to the laboratory standard identification procedures, are included in this study.

RESULTS

A significant decrease of the overall incidence in IPD was observed only in adults from 0.71 to 0.54/100000 populations (P  =  0.02) and to 0.47/100000 populations (P  =  0.0137) in the early and mature post-vaccine period respectively compared to the pre-vaccine period. Our results also showed a significant reduction in the overall prevalence of vaccine serotypes from 28.17 to 6.90% (P  =  0.0021) for the PCV-10 serotypes, and from 46.48 to 25.86% (P  =  0.0164) for the PCV-13 serotypes only in the mature post-vaccine period (2015-2019). In parallel, the rate of non-vaccine serotypes did not significantly change in the early post-vaccine period (2011-2014) while it increased considerably from 54 to 74.14% (P  =  0.0189) during the mature post-vaccine period. The rate of penicillin non-susceptible pneumococcal isolates decreased significantly from 23.94 to 8.77% (P  =  0.02) in adult patients, and the rate of cotrimoxazole non-susceptible pneumococcal isolates significantly decreased from 29.58 to 8.77% in the early post-vaccine period (P  =  0.003) and to 7.24% in the mature post-vaccine period (P  =  0.0007).

CONCLUSION

Although childhood vaccination has considerably reduced the incidence of IPD in adult population through the herd effect, IPD remain a real public health problem due to the alarming increase in non-vaccine serotypes (NVS) and the lack of herd effect among elderly population. The rate of antibiotic resistance was relatively low. Nevertheless, resistance constitutes a serious problem to the therapeutic arsenal due to the known capacity for genetic dissemination in the pneumococcus.

Comparative Analyses of Antibiotic Resistance Genes in Jejunum Microbiota of Pigs in Different Areas

Antibiotic resistance genes (ARGs) are emerging environmental contaminants that threaten human and animal health. Intestinal microbiota may be an important ARGs repository, and intensive animal farming is a likely contributor to the environmental burden of ARGs. Using metagenomic sequencing, we investigated the structure, function, and drug resistance of the jejunal microbial community in Landrace (LA, Kunming), Saba (SB, Kunming), Dahe (DH, Qujing), and Diannan small-ear piglets (DS, Xishuangbanna) from different areas in Yunnan Province, China. Remarkable differences in jejunal microbial diversity among the different pig breeds, while the microbial composition of pig breeds in close areas tends to be similar. Functional analysis showed that there were abundant metabolic pathways and carbohydrate enzymes in all samples. In total, 32,487 ARGs were detected in all samples, which showed resistance to 38 categories of drugs. The abundance of ARGs in jejunum was not significantly different between LA and SB from the same area, but significantly different between DS, DH and LA or SB from different areas. Therefore, the abundance of ARGs was little affected by pig breeds and microorganism community structure, but it was closely related to geographical location. In addition, as a probiotic, Lactobacillus amylovorus is also an important ARGs producing bacterium. Our results revealed the antibiotic exposure and intestinal microbial resistance of farms in the study areas, which could provide basic knowledge and potential strategies for rational use of antibiotics and reducing the risk of ARGs transmission in animal husbandry.

Pediatric Bacterial Meningitis Surveillance in Niger: Increased Importance of Neisseria meningitidis Serogroup C, and a Decrease in Streptococcus pneumoniae Following 13-Valent Pneumococcal Conjugate Vaccine Introduction

BACKGROUND

Meningitis is endemic in Niger. Haemophilus influenzae type b (Hib) vaccine and the 13-valent pneumococcal conjugate vaccine (PCV13) were introduced in 2008 and 2014, respectively. Vaccination campaign against Neisseria meningitidis serogroup A was carried out in 2010-2011. We evaluated changes in pathogen distribution using data from hospital-based surveillance in Niger from 2010 through 2016.

METHODS

Cerebrospinal fluid (CSF) specimens from children <5 years old with suspected meningitis were tested to detect vaccine-preventable bacterial pathogens. Confirmatory identification and serotyping/grouping of Streptococcus pneumoniae, N. meningitidis, and H. influenzae were done. Antimicrobial susceptibility testing and whole genome sequencing were performed on S. pneumoniae isolates.

RESULTS

The surveillance included 2580 patients with suspected meningitis, of whom 80.8% (2085/2580) had CSF collected. Bacterial meningitis was confirmed in 273 patients: 48% (131/273) was N. meningitidis, 45% (123/273) S. pneumoniae, and 7% (19/273) H. influenzae. Streptococcus pneumoniae meningitis decreased from 34 in 2014, to 16 in 2016. PCV13 serotypes made up 88% (7/8) of S. pneumoniae meningitis prevaccination and 20% (5/20) postvaccination. Neisseria meningitidis serogroup C (NmC) was responsible for 59% (10/17) of serogrouped N. meningitidis meningitis. Hib caused 67% (2/3) of the H. influenzae meningitis isolates serotyped. Penicillin resistance was found in 16% (4/25) of S. pneumoniae isolates. Sequence type 217 was the most common lineage among S. pneumoniae isolates.

CONCLUSIONS

Neisseria meningitidis and S. pneumoniae remain important causes of meningitis in children in Niger. The decline in the numbers of S. pneumoniae meningitis post-PCV13 is encouraging and should continue to be monitored. NmC is the predominant serogroup causing N. meningitidis meningitis.

Antibiotic Use in Agriculture and Its Consequential Resistance in Environmental Sources: Potential Public Health Implications

Due to the increased demand of animal protein in developing countries, intensive farming is instigated, which results in antibiotic residues in animal-derived products, and eventually, antibiotic resistance. Antibiotic resistance is of great public health concern because the antibiotic-resistant bacteria associated with the animals may be pathogenic to humans, easily transmitted to humans via food chains, and widely disseminated in the environment via animal wastes. These may cause complicated, untreatable, and prolonged infections in humans, leading to higher healthcare cost and sometimes death. In the said countries, antibiotic resistance is so complex and difficult, due to irrational use of antibiotics both in the clinical and agriculture settings, low socioeconomic status, poor sanitation and hygienic status, as well as that zoonotic bacterial pathogens are not regularly cultured, and their resistance to commonly used antibiotics are scarcely investigated (poor surveillance systems). The challenges that follow are of local, national, regional, and international dimensions, as there are no geographic boundaries to impede the spread of antibiotic resistance. In addition, the information assembled in this study through a thorough review of published findings, emphasized the presence of antibiotics in animal-derived products and the phenomenon of multidrug resistance in environmental samples. This therefore calls for strengthening of regulations that direct antibiotic manufacture, distribution, dispensing, and prescription, hence fostering antibiotic stewardship. Joint collaboration across the world with international bodies is needed to assist the developing countries to implement good surveillance of antibiotic use and antibiotic resistance.

Antimicrobial Activity and Chemical Composition of "Kpètè-Kpètè": A Starter of Benin Traditional Beer Tchoukoutou

The aim of this study was to investigate the antibacterial effect of the crude starter "kpètè-kpètè" and lactic acid bacteria used during the production of "tchoukoutou." To achieve this, a total of 11 lactic acid bacteria and 40 starter samples were collected from four communes. The samples were tested on 29 gram + and - strains by disk diffusion method. The minimum inhibitory and bactericidal concentrations of starter and lactic acid bacteria were determined by conventional methods. Organic acids, sugar, and volatile compounds were determined using the HPLC method. The "kpètè-kpètè" displays a high antibacterial activity against the tested strains. The most sensitive strain was S. epidermidis (12.5 mm) whereas the resistance strain was Proteus mirabilis (8 mm). All the tested ferment has not any inhibitory effect on Enterococcus faecalis. The lactic acid bacteria isolates of Parakou showed the highest (17.48 mm) antibacterial activity whereas the smallest diameter was obtained with the ferment collected from Boukoumbé (9.80 mm). The starters' chemical screening revealed the presence of tannins, anthocyanin flavonoids, triterpenes, steroids, reducing compounds, and mucilage O-glycosides. These compounds are probably the source of recorded inhibition effect. The lactic acid bacteria of the "kpètè-kpètè" could be used to develop a food ingredient with probiotic property.

Antimicrobial potential of 27 plants consumed by chimpanzees (Pan troglodytes verus Blumenbach) in Ivory Coast

BACKGROUND

Due to their genetic proximity, chimpanzees share with human several diseases including bacterial, fungal and viral infections, such as candidiasis, acquired immune deficiency syndrome (AIDS), Ebola virus disease. However, in its natural environment, chimpanzees are tolerant to several pathogens including simian immunodeficiency virus (SIV), virus related to human immunodeficiency virus (HIV) that contribute to the emergence of opportunistic diseases such as microbial infections.

METHODS

Twenty seven species of plants consumed by chimpanzees were evaluated for their antimicrobial potential against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, Candida tropicalis and Candida glabrata using the agar diffusion technique and micro-dilution in 96-well plates. In total 132 extracts (33 dichloromethane, 33 methanol, 33 ethyl acetate and 33 aqueous) were tested.

RESULTS

The results showed that 24 extracts (18 %) showed activity against bacteria and 6 extracts (5 %) were active against yeasts. The minimal inhibitory concentrations (MICs) values of active extracts ranged between 23 and 750 μg/ml for bacteria and between 188 and 1500 μg/ml for yeasts.

CONCLUSION

Tristemma coronatum was the most promising on the studied microorganisms followed by Beilschmiedia mannii. The extracts of the two plants indicated by chimpanzees have potential for antimicrobial use in human.

Knowledge gaps on paediatric respiratory infections in Morocco, Northern Africa

BACKGROUND

The burden of acute respiratory infections (ARI) among Moroccan children remains significant. However, scarce information is available regarding trends in its epidemiology and etiology, or regarding its associated prognostic factors. The purpose of this work was to review available data on the burden of ARI among children under five years of age in Morocco.

METHODS

A systematic review was conducted for the period 1997-2014 using the PRISMA proposed methodology. Various online databases were screened, in addition to physical libraries of Moroccan medical schools, and official reports of the Moroccan Ministry of Health. Search queries in English and French languages included: Respiratory Tract Infections, pneumonia, epidemiology, etiology, microbiology, mortality and Morocco. The documents were included for analysis when they reported original data on the incidence, distribution, or a clinical description of the diseases or their etiology or described clinical management or national preventive strategies.

RESULTS

Thirty-two documents were included in the final analysis. 21 of which had been published. In 2012, ARI caused 13% of paediatric deaths, half of the consultations at health facilities and third of the paediatric admissions. The microorganisms more frequently identified among hospitalized children were Streptococcus pneumoniae (38%) and Haemophilus influenza type b (Hib) (15%). The MOH introduced Hib vaccines into the national immunization program (PNI) in 2007and the 13-valent vaccine against pneumococcus in 2010. The national first line antibiotics recommended for non-severe ambulatory treatment is Amoxicillin. Studies of antibiotic resistance showed from 1998 to 2008 a 22% increase in the rate of penicillin non-susceptibility among Streptococcus pneumoniae isolates. Viral respiratory infections and the role attributed to air pollution in the incidence of ARI have been poorly characterized.

CONCLUSIONS

Further efforts should be made towards the development of adequate surveillance programs to better clarify the epidemiology, etiology, antimicrobial susceptibility patterns and the effectiveness of the preventives and curatives strategies in place against paediatric ARIs in Morocco. Additionally, a holistical approach should be used to identify the heath determinants of ARIs among children.

Antimicrobial Susceptibility Pattern of Invasive Pneumococcal Isolates in North West Nigeria

BACKGROUND

An alarming increase in infections due to penicillin non-susceptible pneumococci (PNSP) has been documented in nearly all countries. Increasingly, PNSP are also resistant to other antibiotics, and a growing number of clinical failures following the use of these agents have been reported.

AIMS

To determine the resistance pattern of pneumococcal isolates from patients with invasive pneumococcal infection in North West Nigeria.

MATERIALS AND METHODS

In a cross-sectional study clinical specimens were obtained from patients with community acquired pneumonia (CAP), meningitis and bacteraemia over a 2 year period. Pneumococcus strains were identified. Isolates were tested against a panel of antibiotics using E-test strips, and interpreted according to the CLSI criteria. 0.06 μg/ml was used as break point for penicillin. Analysis was carried out using descriptive statistics; relationships determined using chi-squared or Fisher's exact tests, with P < 0.05 regarded as significant.

RESULTS

Total number of isolates was 132. Twenty-two (16.7%) of the isolates were fully sensitive to penicillin while 73 (55.3%) and 37 (28.0%) were intermediately and fully resistant, respectively. One hundred and twenty-seven (96.2%) of the isolates were fully resistant to trimethoprim-sulphamethoxazole. Eleven (8.5%) were fully resistant to amoxicillin and 104 (78.8%) and 17 (12.9%) were intermediately resistant and fully susceptible. One hundred and six (80.3%) of the isolates were fully susceptible to chloramphenicol. Resistance to penicillin was shown to infer resistance to other antibiotics.

CONCLUSIONS

Pneumococcal resistance is common in North West Nigeria. Ceftriaxone retains excellent activity against most of the invasive isolate, while trimethoprim-sulphamethoxazole is almost uniformly resistant.

Serotype distribution and antimicrobial resistance of invasive and noninvasive pneumococcal isolates in Tunisia

Pneumococcal conjugate vaccines have not yet been introduced into the national program for childhood vaccination in Tunisia. The aim of this 7-year study was to obtain local data about serotype distribution and antimicrobial resistance of Streptococcus pneumoniae. A total of 203 isolates of culture confirmed that S. pneumoniae was evaluated. Invasive (n=108) and noninvasive (n=95) pneumococcal isolates were obtained from patients aged from 1 month to 85 years old. Considering all age groups, vaccine coverage was 40%, 62%, and 68% for PCV7, PCV10, and PCV13 serotypes, respectively. Overall, 31% of these isolates were penicillin G nonsusceptible. The most prevalent serotypes identified were those found in currently available pneumococcal conjugate vaccines, emphasizing the importance of implementing the vaccine in the routine immunization schedule at the national level.

Antimicrobial drug resistance among clinically relevant bacterial isolates in sub-Saharan Africa: a systematic review

BACKGROUND

Little is known about the prevalence of antimicrobial resistance (AMR) amongst bacterial pathogens in sub-Saharan Africa (sSA), despite calls for continent-wide surveillance to inform empirical treatment guidelines.

METHODS

We searched PubMed and additional databases for susceptibility data of key pathogens for surveillance, published between 1990 and 2013. Extracted data were standardized to a prevalence of resistance in populations of isolates and reported by clinical syndrome, microorganism, relevant antimicrobial drugs and region.

RESULTS

We identified 2005 publications, of which 190 were analysed. Studies predominantly originated from east sSA (61%), were hospital based (60%), were from an urban setting (73%) and reported on isolates from patients with a febrile illness (42%). Quality procedures for susceptibility testing were described in <50% of studies. Median prevalence (MP) of resistance to chloramphenicol in Enterobacteriaceae, isolated from patients with a febrile illness, ranged between 31.0% and 94.2%, whilst MP of resistance to third-generation cephalosporins ranged between 0.0% and 46.5%. MP of resistance to nalidixic acid in Salmonella enterica Typhi ranged between 15.4% and 43.2%. The limited number of studies providing prevalence data on AMR in Gram-positive pathogens or in pathogens isolated from patients with a respiratory tract infection, meningitis, urinary tract infection or hospital-acquired infection suggested high prevalence of resistance to chloramphenicol, trimethoprim/sulfamethoxazole and tetracycline and low prevalence to third-generation cephalosporins and fluoroquinolones.

CONCLUSIONS

Our results indicate high prevalence of AMR in clinical bacterial isolates to antimicrobial drugs commonly used in sSA. Enhanced approaches for AMR surveillance are needed to support empirical therapy in sSA.

Antibiotic susceptibility of streptococcus pyogenes isolated from respiratory tract infections in dakar, senegal

Group A Streptococcus (GAS) is one of the major causes of respiratory tract infections. The objectives of this study were to identify isolates of S. pyogenes obtained from respiratory tract infections, and to assess their susceptibility to several antibiotics. A total of 40 strains were isolated and their susceptibility to 17 antibiotics was tested using a standard disk diffusion method. The minimum inhibitory concentrations (MICs) were determined using the E-test. All isolates were sensitive to β-lactam antibiotics including penicillin, amoxicillin, and cephalosporins. Macrolides remain active with the exception of spiramycin, which showed reduced susceptibility. Out of the 40 isolates, 100% of the isolates were resistant to tetracycline. Interestingly, isolates were sensitive to chloramphenicol, teicoplanin, vancomycine, and levofloxacin, providing potential alternative choices of treatment against infections with S. pyogenes.

Reprint of: Serotyping and antibiotic susceptibility of Streptococcus pneumoniae strains isolated in Algeria from 2001 to 2010

INTRODUCTION

Pneumococcal infections are a major public health problem because of the virulence of this bacterium and its ability to develop resistance.

MATERIAL AND METHOD

Two hundred and ninety-four strains of Streptococcus pneumoniae were isolated from sterile (56.8%) and non-sterile samples (43.2%), from January 2001 to July 2010.

RESULTS

The interpretation of antibiotic susceptibility testing, according to CLSI criteria (M100-S21 2011), yielded a 25.2% overall resistance to penicillin, with 23.5% of strains isolated from CSF (meningitis), and only 1.7% in other samples. Resistance to cefotaxime was 8.1% (including 4.4% at a high level). The most common serotypes were: 14 (19.5%), 23F (9.7%), 6B (9.3%), 19F (5.4%), and serotype 1 (5%). The percentage of these serotypes isolated from normally sterile sites in children under 5 years of age was 31.25% for 14, 10.4% for 23F, 8.3% for 19F, 6.25% for 6B, and 4.2% for serotype 1. The theoretical vaccinal coverage against invasive infections in children under 2 years of age was 61.5%, 69.2%, and 76.9% for the 7-valent, 10-valent, and 13-valent conjugate vaccines, respectively. Penicillin non-susceptible Streptococcus pneumoniae (PNSP) strains accounted for 67.1, 68.6, and 72.8% for each of these three vaccines.

CONCLUSION

There was a variation of serotype rates compared to previous studies. The increase in pneumococcal antibiotic resistance is concerning, particularly for the treatment of pneumococcal infections in children and infants. Pneumococcal vaccination is not compulsory yet in Algeria.

A situational analysis of antimicrobial drug resistance in Africa: are we losing the battle?

BACKGROUND

The first arrival of a sizable shipment of penicillin at the North African Theatre of Operations for USA military use in 1943 was a landmark that turned a new chapter of antibiotic use in Africa. Over the past decade the expansion of resources and the technological advances have meant that much larger quantities of drugs are available in developing countries than ever before. As a result, many more individuals are receiving necessary treatment or therapy than just ten years ago. This very welcome event is accompanied by the terrible irony that increases in drug availability and use can promote drug resistance and render the same life-saving drugs ineffective.

METHODS

The study focused on bacterial pathogens. One hundred and three relevant literatures were identified from the PubMed online database. The coverage included research articles concerning antimicrobial resistance involving subjects of an African country.

RESULTS

Resistant bacteria are on a war path and evidently have acquired an edge over us. Our actions are evidently fuelling the resistance. The indiscriminate use of antibiotics in humans and livestock, wrong and substandard prescriptions by unqualified 'medical personnel' together with poor diagnosis or lack of it are all adding fuel to the already fired train of resistant microbes.

CONCLUSION

To win the war and turn tables as we did with the discovery of penicillin and other antimicrobials in the 1940s, then we must all act now. Antimicrobial stewardship programs-Education, training of laboratory personnel and investment in laboratory infrastructure development are desirable in these situations.

Eleven-year surveillance of antibiotic resistance in Streptococcus pneumoniae in Casablanca (Morocco)

OBJECTIVE

To analyze trends of antibiotic resistance rates in Streptococcus pneumoniae from 1998 to 2008 in Casablanca (Morocco).

METHODS

The antibiotic resistance levels of 955 consecutive nonduplicate isolates were studied using E test and disc diffusion methods. Results were interpreted following Clinical and Laboratory Standards Institute guidelines (2005). Analysis was done according to three periods (1998-2001; 2002-2005; 2006-2008), age, and site of infection.

RESULTS

Penicillin nonsusceptibility (PNS) increased significantly over time (15.6%, 17.8%, and 24.8%; p=0.003). Levels of PNS have changed as well: in 2006-2008, 9.1% of the isolates had an MIC ≥2 μg/ml versus 7.7% in 2002-2005 and 3.4% in 1998-2001. The PNS increase was particularly marked in pediatric isolates (21.4%, 25.5%, and 43.3%; p=0.001). There was no significant difference between the rates of PNS in invasive and noninvasive isolates from children, whereas in adults noninvasive isolates were more penicillin nonsusceptible. Amoxicillin and ceftriaxone nonsusceptible isolates were very rare. An increase of resistance rates was also noticed for erythromycin (9.4%, 12.2%, and 14.4%), tetracycline (20%, 18.6%, and 30.5%), and chloramphenicol (5.6%, 5.6%, and 8.1%). Trimethoprim-sulfamethoxazole resistance rates remained stable (22.8%, 20%, and 23.8%). Proportions of dual nonsusceptibility to penicillin and erythromycin, increased from 5.6% to 8.9%. Multiple drug resistance (resistance to 3 or more antibiotic classes) was found in 0%, 2.4%, and 7.7% of all isolates, respectively.

CONCLUSION

The results reported here maybe useful for guiding update of treatment recommendations and suggest the need for continuous surveillance. Increase of antibiotic resistance correlated with antibiotic consumption, stressing the need for elaboration of antibiotic policy in Morocco.

Assessing sub-Saharan Erythrina for efficacy: traditional uses, biological activities and phytochemistry

The genus Erythrina comprises more than 100 species, widely distributed in tropical and subtropical areas. In Africa, 31 wild species and 14 cultivated species have been described. In sub-Saharan Africa, Erythrina species are used to treat frequent parasitic and microbial diseases, inflammation, cancer, wounds. The rationale of these traditional uses in African traditional medicine was established by screening several species for biological activities. Promising activities were found against bacteria, parasites (Plasmodium), human and phytopathogenic fungi, some of which were multidrug resistant (MDR) micro organisms. Some species also exhibited antioxidant, anti-inflammatory activities and enzymes inhibitory properties. Most of the species chemically investigated were reported to contain flavanones, prenylated isoflavones, isoflavanones and pterocarpans. Some phytochemicals (vogelin B, vogelin C, isowightcone, abyssinin II, derrone) were the active principles as antibacterials, antifungals, antiplasmodials and inhibitors of enzyme borne diseases (PTP1B, HIV protease, DGAT). This review highlights the important role of Erythrina species as sources of lead compounds or new class of phytotherapeutic agents for fighting against major public health (MDR infections, cancer, diabetes, obesity) in sub-Saharan Africa.

Trend in Antibiotic Resistance of Streptococcus Pneumoniae and Haemophilus Influenzae Strains Isolated from Community Acquired Respiratory Tract Infections in Dakar, Senegal between 2005 and 2008

Development of antibiotic resistance among common respiratory pathogens is a major cause of concern worldwide. Streptococcus pneumoniae and Haemophilus influenzae are among the most common respiratory pathogens. In this study, representative samples obtained from 3 different medical centers in Dakar, Senegal were subjected to antibiotic susceptibility testing. The samples were collected from 2005 to 2008 and the data obtained was compared to establish resistance patterns between the two years (i.e. 2005–2006 to 2007–2008). S. pneumoniae exhibited a significant increase in the resistance to azithromycin and the intermediate susceptibility to penicillin G and cotrimoxazole. H. influenzae also exhibited a significant increase in resistance to azithromycin and intermediate susceptibility to chloramphenicol. None of H. influenzae samples were resistant to amoxicillin/clavulanic acid, cephalosporin and fluroquinolones and most of the S. pneumoniae isolates demonstrated high susceptibility to the antibiotics tested. Results from this study will provide greater insights to antibiotic therapy during respiratory tract infections in Dakar, Senegal. This study also establishes the importance of continuous monitoring of antibiotic susceptibility patterns that are often region-specific.

Pneumonia research to reduce childhood mortality in the developing world

Pneumonia is an illness, usually caused by infection, in which the lungs become inflamed and congested, reducing oxygen exchange and leading to cough and breathlessness. It affects individuals of all ages but occurs most frequently in children and the elderly. Among children, pneumonia is the most common cause of death worldwide. Historically, in developed countries, deaths from pneumonia have been reduced by improvements in living conditions, air quality, and nutrition. In the developing world today, many deaths from pneumonia are also preventable by immunization or access to simple, effective treatments. However, as we highlight here, there are critical gaps in our understanding of the epidemiology, etiology, and pathophysiology of pneumonia that, if filled, could accelerate the control of pneumonia and reduce early childhood mortality.

Childhood pyogenic meningitis: clinical and investigative indicators of etiology and outcome

The relevant parameters of 71 consecutive pediatric admissions for pyogenic meningitis at the University of Ilorin Teaching Hospital, Ilorin, Nigeria, were analyzed to identify possible clinical and nonmicrobiologic investigative clues of disease etiology and mortality. Cerebrospinal fluid (CSF) was Gram-smear positive (GSP) in 41 (57.6%) of the 71 cases. Twenty-three (56.1%) had Gram-positive cocci (GPC), 14 (34.2%) Gram-negative bacilli (GNB) and three (7.3%) Gram-negative diplococci (GND). The respective mean ages of GPC, GNB and GND cases were 4.49 +/- 5.3, 3.06 +/- 4.8 and 4.47 +/-4.9 years. Streptococcus pneumoniae accounted for 22 (78.6%) of the 28 CSF isolates (p=0.00), Haemophilus influenzae for two (7.1%) cases and Neisseria meningitides in one (3.5%). Anemia was significantly more common among GSP cases (p=0.04), as was convulsion among those with GNB-positive smears (p=0.03) and a bulging fontanelle in the Gram-smear-negative category. Otherwise, the prevalence and resolution times of the other clinical parameters were comparable across the etiological categories. There were 30 deaths (42.3%) among which GNB-positive cases had significantly shorter stay (p=0.045). Mortality was significantly higher in those with an abnormal respiratory rhythm at admission (p=0.04), purulent/turbid CSF (p=0.03), CSF protein of >150 mg/dl (p=0.02) and glucose <1 mg/dl (p=0.047). Our findings highlight the inherent limitations of predicting the etiology of pediatric meningitides from the clinical parameters as well as the poor prognostic import of respiratory dysrhythmia and a profoundly deranged CSF protein and glucose. The etiological burden of GPC/S. pneumoniae in childhood meningitides in sub-Saharan Africa, the propensity of GNB/H. influenzae for quick fatality and the need for the relevant preventive vaccines are expounded in the discussion.

Laboratory-based surveillance of patients with bacterial meningitis in Egypt (1998–2004)

Laboratory-based surveillance for bacterial meningitis was conducted in a network of infectious disease hospitals in Egypt to better understand the epidemiology of this infection. Healthcare and laboratory personnel were trained in basic surveillance and microbiologic processing of cerebrospinal fluid (CSF) specimens. All bacterial isolates from CSF were confirmed and tested for antimicrobial susceptibility. PCR testing was performed on a random subset of purulent, culture-negative CSF specimens. Of 11,070 patients who met criteria for the case definition, 843 (8%) were culture positive (42% positive for Streptococcus pneumoniae, 20% for Haemophilus influenzae serotype b, 17% for each of Neisseria meningitidis and Mycobacterium tuberculosis, and 6% for other bacteria). Of 1,784 (46%) CSF specimens tested by PCR, 232 (13%) were positive for the first three major pathogens. Of N. meningitidis isolates, 52% belonged to serogroup A, 35% to serogroup B, and 4% to serogroup W135. S. pneumoniae isolates comprised 46 different serotypes, of which 6B, 1, 19A, 23F, and 6A were the most predominant. The overall case-fatality rate for culture-positive cases was 26% and was highest among patients with M. tuberculosis (47%). Factors significantly associated with death (p < 0.05) included admission to rural hospitals, long prodromal period, referral from other hospitals, antibiotic treatment prior to admission, and clear CSF (<100 cells/mm3). Susceptibility to ampicillin and ceftriaxone was observed in 44 and 100% of H. influenzae serotype b isolates and in 52 and 94% of S. pneumoniae isolates, respectively. This surveillance highlights the significant mortality and morbidity associated with bacterial meningitis in Egypt. Decision makers need to review current treatment guidelines and introduce appropriate vaccines for prevention and control of the disease.

Evaluation of 17 medicinal plants from Northern Côte d'Ivoire for their in vitro activity against Streptococcus pneumoniae

Twenty crude extracts from 17 species out of 11 families were assessed for their antibacterial activity against Streptococcus pneumoniae (Pneumococcus). The selected plants are used in Northern Côte d'Ivoire to treat various infections including respiratory track diseases. From all the tested extracts, only 7 from 6 plants showed a promising in vitro bactericidal activity against Pneumococcus, including strains resistant to penicillin. The most active extracts were from Erythrina senegalensis (Fabaceae), Piliostigma thonningii (Caesalpiniaceae), Waltheria indica (Sterculiaceae), Andira inermis (Fabaceae), Uapaca togoensis (Euphorbiaceae), Keetia hispida (Rubiaceae) and Combretum molle (Combretaceae). This is the first time that the antipneumococcal activity of the tested plants is reported. The results of this preliminary investigation support the traditional use of these plants in the treatment of pneumococcal infections. The most active of them could be candidates for isolation of compounds which could serve as lead structures for the development of new drugs against Streptococcus pneumoniae.

Serotype and antimicrobial susceptibility patterns of isolates of Streptococcus pneumoniae causing invasive disease in The Gambia 1996-2003

OBJECTIVES

To describe the characteristics of pneumococcal isolates obtained from patients with invasive pneumococcal disease in The Gambia.

METHODS

Pneumococcal isolates were obtained from children aged < or =6 years with invasive pneumococcal disease during a Haemophilus influenzae vaccine effectiveness study (1997-2002) and from patients with invasive pneumococcal disease admitted to the MRC hospital, Fajara, for routine care (1996-2003). Isolates were identified, serotyped and tested for antibiotic susceptibility.

RESULTS

Five hundred and thirty one pneumococcal isolates were obtained from 518 patients; 55 (10.6%) patients died; 415 isolates (79%) were from blood culture, 84 (16%) from CSF, and 42 (8%) from lung aspirates. Forty serogroups and serotypes were identified; six accounted for 64% and 16 for 86% of all episodes; 33.7% were of serotypes 1 and 5. 23.5% were of a 7-valent vaccine serotype, 57.1% were of a 9-valent vaccine serotype; 56% were of a 7-valent serogroup and 78% were of a 9-valent serogroup. There was a significant increase in the proportion of isolates of non-vaccine serogroup with increasing age (P < 0.0001). Antibiotic resistance had not significantly increased over time; but intermediate non-susceptibility to penicillin had risen and resistance to chloramphenicol had fallen in isolates of vaccine serotype compared with those of non-vaccine serotype.

CONCLUSIONS

The majority of invasive pneumococcal disease in The Gambia is caused by pneumococci of relatively few serogroups. A conjugate vaccine would be expected to reduce the pneumococcal disease burden substantially and to have a beneficial effect on pneumococcal antibiotic resistance to penicillins.

Ceftriaxone as effective as long-acting chloramphenicol in short-course treatment of meningococcal meningitis during epidemics: a randomised non-inferiority study

BACKGROUND

In sub-Saharan Africa in the 1990s, more than 600,000 people had epidemic meningococcal meningitis, of whom 10% died. The current recommended treatment by WHO is short-course long-acting oily chloramphenicol. Continuation of the production of this drug is uncertain, so simple alternatives need to be found. We assessed whether the efficacy of single-dose treatment of ceftriaxone was non-inferior to that of oily chloramphenicol for epidemic meningococcal meningitis.

METHODS

In 2003, we undertook a randomised, open-label, non-inferiority trial in nine health-care facilities in Niger. Participants with suspected disease who were older than 2 months were randomly assigned to receive either chloramphenicol or ceftriaxone. Primary outcome was treatment failure (defined as death or clinical failure) at 72 h, measured with intention-to-treat and per-protocol analyses.

FINDINGS

Of 510 individuals with suspected disease, 247 received ceftriaxone, 256 received chloramphenicol, and seven were lost to follow-up. The treatment failure rate at 72 h for the intention-to-treat analysis was 9% (22 patients) for both drug groups (risk difference 0.3%, 90% CI -3.8 to 4.5). Case fatality rates and clinical failure rates were equivalent in both treatment groups (14 [6%] ceftriaxone vs 12 [5%] chloramphenicol). Results were also similar for both treatment groups in individuals with confirmed meningitis caused by Neisseria meningitidis. No adverse side-effects were reported.

INTERPRETATION

Single-dose ceftriaxone provides an alternative treatment for epidemic meningococcal meningitis--its efficacy, ease of use, and low cost favour its use. National and international health partners should consider ceftriaxone as an alternative first-line treatment to chloramphenicol for epidemic meningococcal meningitis.

Antimicrobial susceptibility and serotype distribution of Streptococcus pneumoniae causing meningitis in Egypt, 1998–2003

OBJECTIVES

To determine the antimicrobial susceptibility and serotype distribution of 205 isolates of Streptococcus pneumoniae, collected from the CSF of meningitis patients identified between 1998-2003, during sentinel meningitis surveillance in Egypt.

METHODS

Antimicrobial susceptibility was evaluated against six antibiotics using disc diffusion and Etest methods. Serotyping was performed by latex agglutination and the Quellung test.

RESULTS

Forty-nine percent of all isolates were found to be non-susceptible to penicillin (46% intermediate, MIC range 0.12-1.0 mg/L; 3% resistant, MIC = 2.0 mg/L), and 6% of the isolates were non-susceptible to ceftriaxone (5% intermediate, MIC = 1.0 mg/L; 1.3% resistant, MIC >/= 2 mg/L). Resistance rates for tetracycline and trimethoprim/sulfamethoxazole were high (52 and 59.7%, respectively), but those for erythromycin and chloramphenicol were lower (11 and 9%, respectively). Five serotypes (6B, 1, 19A, 23F and 6A) accounted for 37% of the total isolates. Ten isolates (5%) were non-typeable. Overall, 29 and 42% of serotypes were represented in the 7- and 11-valent conjugate vaccines, respectively. However, vaccine coverage for children <2 years was 38 and 56% for the 7- and 11-valent, respectively.

CONCLUSIONS

Resistance to penicillin may be increasing among S. pneumoniae strains causing meningitis in Egypt, and a moderate proportion of these strains are not covered by current pneumococcal conjugate vaccines. In addition to intensifying education efforts about judicious use of antibiotics, laboratory-based surveillance for other forms of invasive pneumococcal disease, especially pneumonia, is needed before decisions can be made regarding the most effective vaccines for control of this disease in Egypt.

[Evolution of Streptococcus pneumoniae antibiotic resistance in Abidjan: update on nasopharyngeal carriage, from 1997 to 2001]

The emerging antibiotic resistance and worldwide diffusion of Streptococcus pneumoniae strains is an important public health problem.

OBJECTIVES

The aims of this study were to study the evolution of S. pneumoniae resistance rates to penicillin G and other antimicrobials from nasopharyngeal carriage.

METHOD

Four hundred and eighty-two nasopharyngeal samples of S. pneumoniae were studied from 1997 to 2001. The Kirby-Bauer technique was used to screen the susceptibility of samples and completed with the determination of penicillin G minimal inhibitory concentration using the E-test.

RESULTS

Resistance to penicillin increased from 1997 to 2001: 8.5% in 1997, 20.7% in 1998, 16% in 1999, and 23.5% in 2001. However, the resistance to other beta-lactam antibiotics was low. The rate of resistance to cotrimoxazole increased from 52.2% in 1997 to 84.3% in 2001, with a higher degree of resistance in 2001. The resistance of S. pneumoniae to tetracycline increased. In contrast, the prevalence of erythromycin-resistant pneumococcal samples decreased from 11.6% in 1997 to 8% in 2001. The resistance to three or more antibiotics (multi-drug resistant) was also increased from 9.4% in 1997 to 23.5% in 2001.

CONCLUSION

This data shows that carriage of antibiotic-resistant pneumococci is increasing in Abidjan. It will be interesting to assess the current bacterial resistance patterns by a national epidemiological observatory.

Macrolide resistance in Streptococci and Haemophilus influenzae

Antimicrobial resistance is a growing problem among pathogens from respiratory tract infections. b-Lactam resistance rates are escalating among Streptococcus pneumoniae and Haemophilus influenzae. Macrolides are increasingly used for the treatment of respiratory tract infections, but their utility is compromised by intrinsic and acquired resistance. This article analyses macrolide-resistance mechanisms and their worldwide distributions in S pneumoniae, S pyogenes, and H influenzae.

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.

Mechanisms of resistance to macrolides and lincosamides: nature of the resistance elements and their clinical implications

Resistance to macrolides and lincosamides is increasingly reported in clinical isolates of gram-positive bacteria. The multiplicity of mechanisms of resistance, which include ribosomal modification, efflux of the antibiotic, and drug inactivation, results in a variety of phenotypes of resistance. There is controversy concerning the clinical relevance of in vitro macrolide resistance. Recent data, however, have shown that eradication of bacteria correlates with clinical outcome of acute otitis media in children and that macrolide therapy results in delayed eradication of macrolide-resistant pneumococci. These results support the need for in vitro detection of macrolide resistance and correct interpretation of susceptibility tests to guide therapy.