Antimicrobial resistance of pneumococci in children with acute lower respiratory tract infection in Pakistan

Strain features of pneumococcal isolates in the pre- and post-PCV10 era in Pakistan

Pakistan is amongst the four countries with the highest number of pneumococcal deaths. While the PCV10 vaccine was introduced in Pakistan in October 2012, data regarding the impact of the vaccine on the population dynamics of Streptococcus pneumoniae in Pakistan remain obscure. Using whole genome sequencing of 190 isolates (nasopharyngeal carriage=75, disease=113, unknown sites=2) collected between 2002 and 2020, this study presents characteristics of pneumococcal strains in Pakistan in the pre- and post-vaccine era. The isolates were characterized on the basis of serotype distribution, genetic lineages (or Global Pneumococcal Sequence Cluster, GPSC) and antibiotic resistance. A high level of diversity in serotype and genetic lineages of pneumococci was observed in Pakistan. Among 190 isolates, we identified 54 serotypes, 67 GPSCs and 116 sequence types (STs) including 23 new STs. The most prevalent GPSCs and their associated serotypes in nasopharyngeal carriage were GPSC54 (expressing serotype 9V), GPSC5 (15A and 7B, and serogroup 24), GPSC25 (15B/15C), GPSC67 (18C) and GPSC376 (6A and 6D). Similarly, among 113 disease-causing isolates, the most prevalent GPSC/serotype combinations were GPSC2 (serotype 1), GPSC10 (serotypes 14, 10A, 19A and 19F), GPSC43 (serotypes 13, 11A, 23B, 35A and 9V), GPSC67 (serotypes 18A and 18C) and GPSC642 (serotype 11A). Of the 190 isolates, the highest levels of resistance were observed against penicillin (58.9 %, n=122), erythromycin (29.5 %, n=56), clindamycin (13.2 %, n=25), co-trimoxazole (94.2 %, n=179) and tetracycline/doxycycline (53.2 %, n=101). A higher proportion of disease-causing isolates were multidrug resistant as compared to carriage isolates (54 % vs 25 %). Our data suggest limited coverage of PCV10 in nasopharyngeal (21.6 %, 16/74) as well as disease-causing (38.1 %, 16/42) isolates among children ≤5 years old; however, higher valent vaccine PCV13 would increase the coverage rates to 33.8 % in nasopharyngeal and 54.8 % in disease-causing isolates, whereas PCV24/25 would offer the highest coverage rates. Owing to the diversity of serotypes observed during the post-vaccine period, the suggested inclusion of serotype in future vaccine formulations will require investigations with larger data sets with an extended temporal window. This article contains data hosted by Microreact.

Regional and National Trends in Consumption of Antimicrobials in Pakistan; Pre and Post-COVID (2019-2021)

BACKGROUND

Efforts to combat antimicrobial resistance, a growing public health problem in Pakistan, have been hampered by the lack of high-quality national and provincial-level antimicrobial consumption data. The singular objective of this retrospective study was to measure antimicrobial consumption over 3 years between 2019 and 2021.

METHODS

The study was designed to estimate antimicrobial consumption at National and Regional levels. Antimicrobial consumption data was collected by IQVIA covering 110 districts of Pakistan in which 88% of sales are census (accurate sales collected directly from distributors), whereas 12% of sales (sales of 300 pharmacies) are projected on the national level. To determine the usage for 3 consecutive years, the consumption of antibiotics was calculated as defined daily doses (DDD) of antibiotics per 1000 inhabitants per day (DID).

RESULTS

The results of our study demonstrated a steep increase in the consumption of antimicrobials from 2019 to 2021. An increase in consumption of most classes of antibiotics was observed both nationally and Regionally. Quinolones, penicillins (co-amoxiclav), macrolides, and third-generation cephalosporins remained the most frequently used antibiotics nationally. A 40% increase in intravenous use of antimicrobials was observed between 2019 and 2021 at the national level. Moxifloxacin, Levofloxacin, Ciprofloxacin, and linezolid were the most commonly used intravenous antibiotics. Region 7 (Peshawar) demonstrated the highest consumption, followed by Region 1 (Karachi) and Region 6 (Faisalabad). Among the most commonly used antibiotics, the use of third-generation cephalosporin (cefixime), quinolones, penicillins (amoxicillin + clavulanic acid), and macrolides (azithromycin) was most noticeable in all regions, particularly in those with the higher consumption of antibiotics.

CONCLUSIONS

Although the increase in consumption of all antibiotics is concerning, the steep increase in the use of watch and reserve category antibiotics during the study period calls for immediate actions to limit and regulate their usage.

Ensuring equity with pre-clinical planning for chlamydia vaccines

Chlamydia trachomatis (Ct) remains the most common bacterial sexually transmitted pathogen worldwide, causing significant morbidity particularly among women, including pelvic inflammatory disease, ectopic pregnancy, and infertility. Several vaccines are advancing through pre-clinical and clinical development, and it is likely that one or more vaccines will progress into human efficacy trials soon. In this Perspective, we present a case for considering the challenges of Ct vaccine development through a lens of equity and justice. These challenges include the need to protect against multiple serovars, in both females and males, at multiple anatomic sites, and in resource poor areas of the world. We propose that early consideration of vaccine implementation by conducting community-engaged research will ensure that a scientifically sound chlamydia vaccine promotes equity, justice, and shared-gendered responsibility for STI prevention.

Systematic review of the clinical outcomes of pneumonia with a penicillin-group resistant pneumococcus in respiratory and blood culture specimens in children in low- and middle-income countries

Background

Streptococcus pneumoniae is one of the most common bacteria causing pneumonia and the World Health Organization (WHO) recommends first-line treatment of pneumonia with penicillins. Due to increases in the frequency of penicillin resistance, this systematic review aimed to determine the clinical outcomes of children with pneumonia in low- and middle-income countries (LMICs), with penicillin-group resistant pneumococci in respiratory and/or blood cultures specimens.

Methods

English-language articles from January 2000 to November 2020 were identified by searching four databases. Systematic reviews and epidemiological studies from LMICs that included children aged one month to 9 years and reported outcomes of pneumonia with a penicillin-resistant pneumococcus in respiratory and blood culture specimens with or without comparison groups were included. Risk of bias was assessed using the Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for Quantitative Studies. A narrative synthesis of findings based on the results of included studies was performed.

Results

We included 7 articles involving 2864 children. One strong- and four medium-quality studies showed no difference in clinical outcomes (duration of symptoms, length of hospital stay and mortality) between those children with penicillin non-susceptible compared to susceptible pneumococci. Two weak quality studies suggested better outcomes in the penicillin-susceptible group.

Conclusions

Current evidence suggests no difference in clinical outcomes of child pneumonia due to a penicillin-resistant S. pneumoniae and as such, there is no evidence to support a change in current WHO antibiotic guidelines.

Antimicrobial Resistance in Pneumococcal Carriage Isolates from Children under 2 Years of Age in Rural Pakistan

Antimicrobial resistance is an emerging public health concern. Ten-valent pneumococcal vaccine (PCV10) was introduced in Pakistan’s Expanded Program on Immunization (EPI) in 2012 as a 3 + 0 schedule without catchup. From 2014 to 2018, children <2 years were randomly selected in two rural union councils of Matiari, Pakistan. Nasopharyngeal swabs were collected using standard WHO guidelines by trained staff and processed at Infectious Disease Research Laboratory at The Aga Khan University, Karachi using culture on sheep blood agar and Multiplex PCR methods described by CDC, USA. Pneumococcal isolates were identified by optochin sensitivity and bile solubility tests. Isolates were then tested for antimicrobial susceptibility by standard Kirby-Bauer disk-diffusion method on Mueller-Hinton Agar (MHA) with 5% sheep blood agar as per Clinical & Laboratory Standards Institute (CLSI) recommendations. Of 3140 children enrolled, pneumococcal isolates were detected in 2370 (75%). Vaccine coverage improved from 41% to 68.4%. Out of the 2370 isolates, 88.4%, 37.6% and 25% were resistant to cotrimoxazole, tetracycline and erythromycin, respectively. There was no resistance to penicillin, ceftriaxone, and vancomycin. For erythromycin, resistance increased from 20% in 2014/15 to 30.8% in 2017/18 and for tetracycline it increased from 34.9% to 41.8% both of which were explained by an increase in prevalence of serotype 19A. Pneumococcal isolates were susceptible to penicillin, ceftriaxone, and vancomycin. They were largely resistant to cotrimoxazole and tetracycline. There was an increase in erythromycin and tetracycline resistance attributed to increasing prevalence of serotype 19A. Pneumococcal isolates from carriage and invasive disease should be closely monitored for antimicrobial susceptibility.

IMPORTANCE Antimicrobial resistance is an emerging public health concern particularly in low- and middle-income countries where there is poor regulation and easy availability of antibiotics. This is the first study from Pakistan to report antimicrobial resistance patterns of pneumococcus after vaccine introduction in the community. Pakistan was the first South-Asian country to introduce PCV10 in its Expanded Program on Immunization (EPI) in 2012 as a 3 + 0 schedule without catchup. In this study, we describe the PCV10 impact on antimicrobial resistance patterns of pneumococcal nasopharyngeal carriage in children younger than 2 years of age in a rural district in Pakistan after the introduction of the vaccine.

Comparison of 3 Days Amoxicillin Versus 5 Days Co-Trimoxazole for Treatment of Fast-breathing Pneumonia by Community Health Workers in Children Aged 2-59 Months in Pakistan: A Cluster-randomized Trial

Background

Globally, most deaths due to childhood pneumonia occur at the community level. Some countries are still using oral co-trimoxazole, despite a World Health Organization recommendation of oral amoxicillin for the treatment of fast-breathing pneumonia in children at the community level.

Methods

We conducted an unblinded, cluster-randomized, controlled-equivalency trial in Haripur District, Pakistan. Children 2–59 months of age with fast-breathing pneumonia were treated with oral amoxicillin suspension (50 mg/kg/day) for 3 days in 14 intervention clusters and oral co-trimoxazole suspension (8 mg trimethoprim/kg and 40 mg sulfamethoxazole/kg/day) for 5 days in 14 control clusters by lady health workers (LHW). The primary outcome was treatment failure by day 4 for intervention clusters and by day 6 for control clusters. The analysis was per protocol.

Results

Out of the 15 749 cases enrolled in the study, 9153 cases in intervention and 6509 cases in control clusters were included in the analysis. Treatment failure rates were 3.6% (326) in intervention clusters and 9.1% (592) in control clusters. After adjusting for clustering, the risk of treatment failure was lower in intervention clusters (risk difference [RD] -5.5%, 95% confidence interval [CI] -7.4–-3.7%) than in control clusters. Children with incomplete adherence had a small increase in treatment failure versus those with complete adherence (RD 2.9%, 95% CI 1.6–4.1%). No deaths or serious adverse events occurred.

Conclusions

A 3-day course of oral amoxicillin, administered by LHWs, is an effective and safe treatment for fast-breathing pneumonia in children 2–59 months of age. A shorter course of amoxicillin improves adherence to therapy, is low in cost, and puts less pressure on antimicrobial resistance.

Clinical Trials Registration

ISRCTN10618300.

Performance of the Biomark HD real-time qPCR System (Fluidigm) for the detection of nasopharyngeal bacterial pathogens and Streptococcus pneumoniae typing

Traditional qPCR assays for pneumococcal detection and serotype characterization require large sample volume, is expensive and labor intensive. We aimed to develop a quantitative nanofluidic Fluidigm assay to overcome some of these shortcomings. A quantitative Fluidigm assay was established to detect 11 bacterial pathogens, 55 pneumococcal serotypes and 6 serotypes of H. influenzae. The Fluidigm assay results were compared to conventional qPCR and culture. All reactions in the Fluidigm assay effectively amplified their respective targets with high sensitivity and specificity compared to qPCR. There was excellent concordance between qPCR and Fluidigm for detection of carriage prevalence (kappa > 0.75) and density (Rho > 0.95). Fluidigm identified an additional 7 (4.2%) serotypes over those detected by qPCR. There was a modest concordance between culture and Fluidigm for the majority of reactions detecting S. pneumoniae serotypes/serogroups (kappa > 0.6), with Fluidigm identifying an additional 113 (39.1%) serotypes. Discordant results between the three methods were associated with a low carriage density. The Fluidigm assay was able to detect common pneumococcal serotypes, H. influenzae serotypes, and other common nasopharyngeal bacterial organisms simultaneously. Deployment of this assay in epidemiological studies could provide better insight into the effect of PCV immunization on the nasopharyngeal microbiota in the community.

Molecular Characterization of Pneumococcal Surface Protein A (PspA), Serotype Distribution and Antibiotic Susceptibility of Streptococcus pneumoniae Strains Isolated from Pakistan

INTRODUCTION

Pakistan has one of the highest burdens of pneumococcal diseases in the world, but unfortunately studies in this demanding research area are limited in the region. Pneumococcal surface protein A (PspA) is the next generation pneumococcal vaccine candidate as the protein locates on the Streptococcus pneumoniae surface. Its gene, pspA, might be encoded by all pneumococci, and the protein has proven immunogenicity. The molecular characterization of PspA, pneumococcal serotype distribution and antibiotic susceptibility are important for regional diversity studies.

METHODS

In this study, we examined 38 pneumococcal isolates from pneumococcal diseased (pneumonia/meningitis) patients blood or cerebrospinal fluid. There were no specific inclusion or exclusion criteria, but all the individuals [ages 1 month to 12 years (male/female)] had undergone no antibiotic treatment in at least the past 3 months and had no vaccination history. We investigated the serotype distribution, antibiotic susceptibility, prevalence of the PspA family and its active domain's fusion, expression and antigenicity.

RESULTS

Our finding shows that serotype 19F is the most prevalent (23.6%) followed by 18B (15.78%) (non-vaccine type) in all isolated pneumococcal strains. All strains were susceptible to chloramphenicol and linezolid, while 80% were resistant to gentamycin. Genotyping revealed that ~ 80% (N = 31/38) of pneumococcal strains produce PspA belonging to family 2 and clade 3. We further selected three active domains of PspA (family 2 and clade 3) by in silico analysis, merged together into a fusion gene for expression study, and its antigenicity was analyzed by Western blotting.

CONCLUSION

Serotypes 19F and 18B (non-vaccine type) are the most prevalent in the Pakistani pneumococcal isolates. The PspA family 2 proteins produced by Pakistani pneumococcal isolates have high sequence homologies with each other and differ from those produced by strains isolated in the rest of the world. The PspA fusion peptide had a proven antigenic response in western blotting, with no considerable correlation among pneumococcal serotypes, antibiotic susceptibility and PspA family/clade distribution.

Comparison of traditional culture and molecular qPCR for detection of simultaneous carriage of multiple pneumococcal serotypes in African children

S. pneumoniae is a common colonizer of the human nasopharynx in high income and low-middle income countries. Due to limitations of standard culture methods, the prevalence of concurrent colonization with multiple serotypes is unclear. We evaluated the use of multiplex quantitative PCR (qPCR) to detect multiple pneumococcal serotypes/group colonization in archived nasopharyngeal swabs of pneumococcal conjugate vaccine naive children who had previously been investigated by traditional culture methods. Overall the detection of pneumococcal colonization was higher by qPCR (82%) compared to standard culture (71%; p < 0.001), with a high concordance (kappa = 0.73) of serotypes/groups identified by culture also being identified by qPCR. Also, qPCR was more sensitive in detecting multiple serotype/groups among colonized cases (28.7%) compared to culture (4.5%; p < 0.001). Of the additional serotypes detected only by qPCR, the majority were of lower density (<10⁴ CFU/ml) than the dominant colonizing serotype, with serotype/group 6A/B, 19B/F and 23F being the highest density colonizers, followed by serotype 5 and serogroup 9A/L/N/V being the most common second and third colonizers respectively. The ability of qPCR to detect multiple pneumococcal serotypes at a low carriage density might provide better insight into underlying mechanism for changes in serotype colonization in PCV vaccinated children.

Respiratory syncytial virus and influenza are the key viral pathogens in children <2 years hospitalized with bronchiolitis and pneumonia in Islamabad Pakistan

Pneumonia remains a leading cause of morbidity and mortality in developing countries. Comprehensive surveillance data are needed to review the prevention and control strategies. We conducted active surveillance of acute lower respiratory infections among children aged <2 years hospitalized at two hospitals of Islamabad, Pakistan. Viral etiology was determined using real-time PCR on respiratory specimens collected during March 2011-April 2012. The overall mean age was 7.83 ± 5.25 months while no statistical difference between age or sex distribution of patients with positive and negative viral etiology (p > 0.05). The average weight of the study group was 6.1 ± 2.25 kg. ≥1 viral pathogens were detected in 75% cases. Major respiratory viruses included RSV-A: 44%, RSV-B: 23%, Influenza-A: 24.5%, Influenza-B: 7%, Adenovirus: 8.4% and HmPV: 5.2%. A single, dual or multiple viral pathogens were detected in 43%, 27% and 5.2% patients respectively. Common symptoms were cough (95%), apnoea (84%), fever (78%), wheeze (64.5%), nasal congestion (55%) and rhinorrhea (48%). Among the RSV positive cases, 2-6 months age group had highest detection rate for RSV-A (30%, n = 21/69) and RSV-B (20%, n = 14/69) while patients infected with Influenza-A were in 2.1-6 months age group (61%, 23/38). Statistically significant difference was observed between RSV-positive and negative cases for nutrition status (p = 0.001), cigarette/wood smoke exposure (p = 0.001) and concomitant clinical findings. Most patients had successful outcome on combination therapy with bronchodilators, inhaled steroids and antibiotics. Our findings underscore high burden of ALRI in Pakistan. Interventions targeting viral pathogens coupled with improved diagnostic approaches are critical for better prevention and control.

Assessment of antibiotic self-medication practice among public in the northwestern region of Pakistan

Background

Self-medication with antibiotics is a common practice, which may lead to the development of antimicrobial resistance (AMR)-a major health concern worldwide. The most common reason for the development of AMR is a lack of education and regulatory policies and the lack of community pharmacists.

Objective

To assess various factors that lead to self-medication with antibiotics, which might cause AMR and hinder effective healthcare.

Methods

A cross-sectional study was carried out using a predesigned questionnaire to collect data from 800 respondents. The respondents were selected by simple random sampling during November 2014 to January 2015 from different regions of Khyber Pakhtunkhwa (KPK), Pakistan. Only properly completed questionnaires were assessed for different variables. The collected data were analysed using SPSS V.16.

Results

527 people completed and returned the questionnaire-a response rate of 66%. Self-medication with antibiotics was reported by 135 participants (26%), with a higher prevalence of men than women (48% vs 38%, respectively). The main reason for self-medication was previous experience with the same antibiotic (68%). The most commonly used antibiotics were amoxicillin-clavulanate (40%) and major indications for self-medication were sore throat (29%) and flu (24%). Of the 527 respondents, only 104 (20%) were aware of AMR.

Conclusions

This study is the first to evaluate self-medication with antibiotics in KPK, Pakistan. In view of the high prevalence of self-medication, introduction of a public health policy through drug regulatory authorities, public awareness programmes/campaigns, patient education about AMR and appropriate use of antibiotics are critically required. The role of community pharmacists needs to be strengthened.

Credit where credit is due: Pakistan's role in reducing the global burden of reproductive, maternal, newborn, and child health (RMNCH)

Factors contributing to Pakistan’s poor progress in reducing reproductive, maternal, newborn, and child health (RMNCH) include its low level of female literacy, gender inequity, political challenges, and extremism along with its associated relentless violence; further, less than 1% of Pakistan’s GDP is allocated to the health sector. However, despite these disadvantages, Pakistani researchers have been able to achieve positive contributions towards RMNCH-related global knowledge and evidence base, in some cases leading to the formulation of WHO guidelines, for which they should feel proud. Nevertheless, in order to improve the health of its own women and children, greater investments in human and health resources are required to facilitate the generation and use of policy-relevant knowledge. To accomplish this, fair incentives for research production need to be introduced, policy and decision-makers’ capacity to demand and use evidence needs to be increased, and strong support from development partners and the global health community must be secured.

Bacterial meningitis in children under 15 years of age in Nepal

BACKGROUND

Bacterial meningitis in children is a life-threatening problem resulting in severe morbidity and mortality. For the prompt initiation of antibacterial therapy, rapid and reliable diagnostic methods are of utmost importance. Therefore, this study was designed to find out the rate of bacterial pathogens of meningitis from suspected cases by performing conventional methods and latex agglutination.

METHODS

A descriptive type of study was carried out from May 2012 to April 2013. Cerebrospinal fluid (CSF) specimens from 252 suspected cases of meningitis were subjected for Gram staining, bacterial culture and latex agglutination test. The identification of growth of bacteria was done following standard microbiological methods recommended by American Society for Microbiology. Antibiotic sensitivity testing was done by modified Kirby-Bauer disk diffusion method.

RESULTS

From the total 252 suspected cases, 7.2 % bacterial meningitis was revealed by Gram staining and culture methods whereas latex agglutination method detected 5.6 %. Gram-negative organisms contributed the majority of the cases (72.2 %) with Haemophilus influenzae as the leading pathogen for meningitis. Overall, 33.3 % mortality rate was found.

CONCLUSIONS

In conclusion, a significant rate of bacterial meningitis was found in this study prompting concern for national wide surveillance.

Distribution of serotypes, vaccine coverage, and antimicrobial susceptibility pattern of Streptococcus pneumoniae in children living in SAARC countries: a systematic review

INTRODUCTION

Each SAARC nation falls in the zone of high incidence of pneumococcal disease but there is a paucity of literature estimating the burden of pneumococcal disease in this region.

OBJECTIVE

To identify the prevalent serotypes causing invasive pneumococcal disease in children of SAARC countries, to determine the coverage of these serotypes by the available vaccines, and to determine the antibiotic resistance pattern of Streptococcus pneumoniae.

METHODS

We searched major electronic databases using a comprehensive search strategy, and additionally searched the bibliography of the included studies and retrieved articles till July 2014. Both community and hospital based observational studies which included children aged ≤12 years as/or part of the studied population in SAARC countries were included.

RESULTS

A total of 17 studies were included in the final analysis. The period of surveillance varied from 12-96 months (median, 24 months). The most common serotypes country-wise were as follows: serotype 1 in Nepal; serotype 14 in Bangladesh and India; serotype 19F in Sri Lanka and Pakistan. PCV-10 was found to be suitable for countries like India, Nepal, Bangladesh, and Sri Lanka, whereas PCV-13 may be more suitable for Pakistan. An increasing trend of non-susceptibility to antibiotics was noted for co-trimoxazole, erythromycin and chloramphenicol, whereas an increasing trend of susceptibility was noted for penicillin.

CONCLUSION

Due to paucity of recent data in majority of the SAARC countries, urgent large size prospective studies are needed to formulate recommendations for specific pneumococcal vaccine introduction and usage of antimicrobial agents in these regions.

Pneumococcal serotypes and serogroups causing invasive disease in Pakistan, 2005-2013

While pneumococcal conjugate vaccines have been implemented in most countries worldwide, use in Asia has lagged in part because of a lack of data on the amount of disease that is vaccine preventable in the region. We describe pneumococcal serotypes elicited from 111 episodes of invasive pneumococcal disease (IPD) from 2005 to 2013 among children and adults in Pakistan. Seventy-three percent (n = 81) of 111 IPD episodes were cases of meningitis (n = 76 in children 0–15 years and n = 5 among adults). Serotypes were determined by target amplification of DNA extracted from pneumococcal isolates (n = 52) or CSF specimens (n = 59). Serogroup 18 was the most common serogroup causing meningitis in children <5 years, accounting for 21% of cases (n = 13). The 10-valent pneumococcal conjugate vaccine (PCV 10) or PCV10- related serotypes were found in 61% (n = 47) of childhood (age 0–15 years) meningitis episodes. PCV-13 increased this coverage to 63% (one additional serotype 19A; n = 48). Our data indicate that use of PCVs would prevent a large proportion of serious pneumococcal disease.

Burden of invasive pneumococcal disease in children aged 1 month to 12 years living in South Asia: a systematic review

Objective

The primary objective was to estimate the burden of invasive pneumococcal disease (IPD) in children aged 1 month to 12 years in South Asian countries.

Methods

We searched three electronic databases (PubMed, Embase and the Cochrane Library) using a comprehensive search strategy, we manually searched published databases (Index Medicus and Current Contents) and we also searched the bibliographies of the included studies and retrieved reviews. The searches were current through June 2013. Eligible studies (community-based and hospital-based) were pooled and a separate analysis for India was also completed. A meta-regression analysis and heterogeneity analysis were performed. The protocol was registered with PROSPERO registration number CRD42013004483.

Results

A total of 22 studies surveying 36,714 children were included in the systematic review. Hospital-based prospective studies from South Asia showed that 3.57% of children had IPD, and 15% of all bacterial pneumonia cases were due to Streptococcus pneumoniae. Indian studies showed that the incidence of IPD was 10.58% in children admitted to hospitals with suspected invasive bacterial diseases, and 24% of all bacterial pneumonia cases were due to S. pneumonia. Population-based studies from South Asian countries showed that 12.8% of confirmed invasive bacterial diseases were caused by S. pneumonia whereas retrospective hospital-based studies showed that 28% of invasive bacterial diseases were due to S. pneumoniae. Meta-regression showed that there was a significant influence of the antigen testing method for diagnosing IPD on IPD prevalence.

Conclusion

S. pneumoniae is responsible for a substantial bacterial disease burden in children of South Asian countries including India despite the presence of high heterogeneity in this meta-analysis. Treatment guidelines must be formulated, and preventive measures like vaccines must also be considered.

A prospective study of inpatients to determine microbial etiology and therapeutic outcome of antibiotics for community-acquired pneumonia in pakistan

INTRODUCTION

Community-acquired pneumonia (CAP) is among the common diseases that causes illness and death world-wide. Limited data is available for the treatment of patients with CAP and/or medical outcome of CAP patients in Pakistan. This cross-sectional and prospective study was done to determine etiology of CAP patients and to evaluate the therapeutic effects of antibiotics commonly used in treating CAP patients in two different inner-city hospitals, Pakistan.

METHODS

The study was conducted on 200 hospitalized patients presenting clinical and radiographic evidences of CAP. The patients were assessed for the causative pathogen and their prescriptions were analyzed for the management and treatment of CAP and associated symptoms of pneumonia. Finally the medical outcomes were evaluated.

RESULTS

On establishing the microbial etiology of pneumonia among different CAP causing pathogens, K. pneumoniae was found to be the most identified causative agent (30%) followed by S. pneumoniae (23%). Majority of the patients received cephalosporin antibiotics (80%) followed by aminoglycosides (65%) and penicillins (50%) either as monotherapy or combination treatment. Therapeutic success was observed to occur in majority of the patients. The recovery of CAP patients occurred probably because they received antibiotics which are recommended by WHO and American Thoracic Society. Another reason for successful therapeutic outcome was found to be the significant patient compliance for treatment.

CONCLUSION

There is a great need for such types of investigational studies to be conducted in developing countries which may guide the empirical therapy and help in defining proper treatment guidelines.

Distribution of Streptococcus pneumoniae serotypes that cause parapneumonic empyema in Turkey

Streptococcus pneumoniae is the most common etiological cause of complicated pneumonia, including empyema. In this study, we investigated the serotypes of S. pneumoniae that cause empyema in children. One hundred fifty-six children who were diagnosed with pneumonia complicated with empyema in 13 hospitals in seven geographic regions of Turkey between 2010 and 2012 were included in this study. Pleural fluid samples were collected by thoracentesis and tested for 14 serotypes/serogroups using a Bio-Plex multiplex antigen detection assay. The serotypes of S. pneumoniae were specified in 33 of 156 samples. The mean age ± the standard deviation of the 33 patients was 6.17 ± 3.54 years (range, 0.6 to 15 years). All of the children were unvaccinated according to the vaccination reports. Eighteen of the children were male, and 15 were female. The serotypes of the non-7-valent pneumococcal conjugated vaccine (non-PCV-7), serotype 1, serotype 5, and serotype 3, were detected in eight (14.5%), seven (12.7%), and five (9.1%) of the samples, respectively. Serotypes 1 and 5 were codetected in two samples. The remaining non-PCV-7 serotypes were 8 (n = 3), 18 (n = 1), 19A (n = 1), and 7F/A (n = 1). PCV-7 serotypes 6B, 9V, 14, 19F, and 23F were detected in nine (16.3%) of the samples. The potential serotype coverages of PCV-7, PCV-10, and PCV-13 were 16.3%, 45.4%, and 60%, respectively. Pediatric parapneumonic empyema continues to be an important health problem despite the introduction of conjugated pneumococcal vaccines. Active surveillance studies are needed to monitor the change in S. pneumoniae serotypes that cause empyema in order to have a better selection of pneumococcal vaccines.

Global prevailing and emerging pediatric pneumococcal serotypes

Streptococcus pneumoniae is the leading cause of vaccine-preventable deaths among children younger than 5 years of age worldwide. The 7-valent pneumococcal conjugate vaccine (PCV7) is currently licensed in more than 90 countries and has contributed to significant declines in the incidence of invasive pneumococcal disease (IPD). Recent studies report an increased incidence of IPD caused by non-PCV7 vaccine serotypes (NVTs). Seroepidemiology of IPD caused by NVTs following the introduction of PCV7 is of interest, and this article provides a comprehensive global summary of the prevailing and emerging serotypes causing IPD in children. Currently, globally emerging or persistent NVTs include serotypes 1, 3, 5, 6A, 7F and 19A. Serotypes included in the recently licensed 10-valent pneumococcal Haemophilus influenzae protein D conjugate vaccine (PCV10) and 13-valent pneumococcal conjugate vaccine (PCV13) account for pneumococcal disease burdens in most developed countries of 65-85% and 80-90%, respectively. The seroprevalence of NVTs after widespread use of PCV10 and PCV13 requires ongoing monitoring.

Incidence of pneumonia, bacteremia, and invasive pneumococcal disease in Pakistani children

OBJECTIVE

To determine the incidence of pneumonia, bacteremia, and invasive pneumococcal disease (IPD) in Pakistani children <5 years old.

METHODS

Household surveillance from 1st February 2007 to 12th May 2008 was conducted in two low-income, coastal communities of Karachi. Community health workers referred each sick child <5 years old to the local clinic. Blood culture was obtained whenever possible from children meeting inclusion criteria.

RESULTS

Overall, 5570 children contributed 3949 observation years. There were 1039 clinical cases of pneumonia, of which 54 were severe pneumonia and four cases of very severe disease according to WHO criteria. The overall pneumonia incidence was 0.26 (95% CI: 0.25-0.28) episodes per child-year. A pathogen was isolated from the blood of 29 (2.8%) pneumonia cases. Bacteremia incidence was 912 (95% CI: 648-1248) episodes per 100,000 child-years with a case fatality rate of 8%. The detected IPD incidence was 25 (95% CI: 1-125) episodes per 100,000 child-years. The under-five mortality rate was 55 per 1000 live births, with pneumonia causing 12 (22%) deaths among children <5 years old.

CONCLUSION

Clinical pneumonia is common in Pakistani children, with one in four deaths attributable to the disease. Bacteremia occurs at a high rate but surveillance for pneumococcus underestimates the burden of IPD.

Overview of the disease burden of invasive pneumococcal disease in Asia

This paper represents a collaborative effort by the Asian Strategic Alliance for Pneumococcal Disease Prevention (ASAP) Working Group to collate data on the disease burden due to invasive pneumococcal disease (IPD) in participating Asian countries and territories; namely, Hong Kong, India, Indonesia, Korea, Macau, Malaysia, Pakistan, the Philippines, Singapore, Sri Lanka, Taiwan and Thailand. A review of both published and unpublished data revealed that the incidence of IPD in some countries is well documented by way of large, long-duration studies, while in other countries, much of the available data have been extrapolated from international studies or have come from small population studies of limited geographical coverage. This paper confirms that data regarding the incidence of IPD in Asia are grossly lacking and reinforces the need for urgent and more substantial studies.

Identification of serotype in culture negative pneumococcal meningitis using sequential multiplex PCR: implication for surveillance and vaccine design

Background

PCR-based serotyping of Streptococcus pneumoniae has been proposed as a simpler approach than conventional methods, but has not been applied to strains in Asia where serotypes are diverse and different from other part of the world. Furthermore, PCR has not been used to determine serotype distribution in culture-negative meningitis cases.

Methodology

Thirty six serotype-specific primers, 7 newly designed and 29 previously published, were arranged in 7 multiplex PCR sets, each in new hierarchies designed for overall serotype distribution in Bangladesh, and specifically for meningitis and non-meningitis isolates. Culture-negative CSF specimens were then tested directly for serotype-specific sequences using the meningitis-specific set of primers. PCR-based serotyping of 367 strains of 56 known serotypes showed 100% concordance with quellung reaction test. The first 7 multiplex reactions revealed the serotype of 40% of all, and 31% and 48% non-meningitis and meningitis isolates, respectively. By redesigning the multiplex scheme specifically for non-meningitis or meningitis, the quellung reaction of 43% and 48% of respective isolates could be identified. Direct examination of 127 culture-negative CSF specimens, using the meningitis-specific set of primers, yielded serotype for 51 additional cases.

Conclusions

This PCR approach, could improve ascertainment of pneumococcal serotype distributions, especially for meningitis in settings with high prior use of antibiotics.

Chloramphenicol versus ampicillin plus gentamicin for community acquired very severe pneumonia among children aged 2-59 months in low resource settings: multicentre randomised controlled trial (SPEAR study)

OBJECTIVE

To evaluate whether five days' treatment with injectable ampicillin plus gentamicin compared with chloramphenicol reduces treatment failure in children aged 2-59 months with community acquired very severe pneumonia in low resource settings.

DESIGN

Open label randomised controlled trial.

SETTING

Inpatient wards within tertiary care hospitals in Bangladesh, Ecuador, India, Mexico, Pakistan, Yemen, and Zambia.

PARTICIPANTS

Children aged 2-59 months with WHO defined very severe pneumonia.

INTERVENTION

Chloramphenicol versus a combination of ampicillin plus gentamicin.

MAIN OUTCOME MEASURES

Primary outcome measure was treatment failure at five days. Secondary outcomes were treatment failure defined similarly among all participants evaluated at 48 hours and at 10 and 21 days.

RESULTS

More children failed treatment with chloramphenicol at day 5 (16% v 11%; relative risk 1.43, 95% confidence interval 1.03 to 1.97) and also by days 10 and 21. Overall, 112 bacterial isolates were obtained from blood and lung aspirates in 110 children (11.5%), with the most common organisms being Staphylococcus aureus (n=47) and Streptococcus pneumoniae (n=22). In subgroup analysis, bacteraemia with any organism increased the risk of treatment failure at 21 days in the chloramphenicol group (2.09, 1.41 to 3.10) but not in the ampicillin plus gentamicin group (1.12, 0.59 to 2.13). Similarly, isolation of S pneumoniae increased the risk of treatment failure at day 21 (4.06, 2.73 to 6.03) and death (5.80, 2.62 to 12.85) in the chloramphenicol group but not in the ampicillin plus gentamicin group. No difference was found in treatment failure for children with S aureus bacteraemia in the two groups, but the power to detect a difference in this subgroup analysis was low. Independent predictors of treatment failure by multivariate analysis were hypoxaemia (oxygen saturation <90%), receiving chloramphenicol, being female, and poor immunisation status.

CONCLUSION

Injectable ampicillin plus gentamicin is superior to injectable chloramphenicol for the treatment of community acquired very severe pneumonia in children aged 2-59 months in low resource settings.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN39543942.

Ambulatory short-course high-dose oral amoxicillin for treatment of severe pneumonia in children: a randomised equivalency trial

BACKGROUND

WHO case management guidelines for severe pneumonia involve referral to hospital for treatment with parenteral antibiotics. If equally as effective as parenteral treatment, home-based oral antibiotic treatment could reduce referral, admission, and treatment costs. Our aim was to determine whether home treatment with high-dose oral amoxicillin and inpatient treatment with parenteral ampicillin were equivalent for the treatment of severe pneumonia in children.

METHODS

This randomised, open-label equivalency trial was done at seven study sites in Pakistan. 2037 children aged 3-59 months with severe pneumonia were randomly allocated to either initial hospitalisation and parenteral ampicillin (100 mg/kg per day in four doses) for 48 h, followed by 3 days of oral amoxicillin (80-90 mg/kg per day; n=1012) or to home-based treatment for 5 days with oral amoxicillin (80-90 mg/kg per day in two doses; n=1025). Follow-up assessments were done at 1, 3, 6, and 14 days after enrollment. The primary outcome was treatment failure (clinical deterioration) by day 6. Analyses were done per protocol and by intention to treat. This trial is registered, ISRCTN95821329.

FINDINGS

In the per-protocol population, 36 individuals were excluded from the hospitalised group and 37 from the ambulatory group, mainly because of protocol violations or loss to follow-up. There were 87 (8.6%) treatment failures in the hospitalised group and 77 (7.5%) in the ambulatory group (risk difference 1.1%; 95% CI -1.3 to 3.5) by day 6. Five (0.2%) children died within 14 days of enrollment, one in the ambulatory group and four in the hospitalised group. In each case, treatment failure was declared before death and the antibiotic had been changed. None of the deaths were considered to be associated with treatment allocation; there were no serious adverse events reported in the trial.

INTERPRETATION

Home treatment with high-dose oral amoxicillin is equivalent to currently recommended hospitalisation and parenteral ampicillin for treatment of severe pneumonia without underlying complications, suggesting that WHO recommendations for treatment of severe pneumonia need to be revised.

Comparison of standard versus double dose of amoxicillin in the treatment of non-severe pneumonia in children aged 2-59 months: a multi-centre, double blind, randomised controlled trial in Pakistan

INTRODUCTION

WHO pneumonia case management guidelines recommend oral amoxicillin as first line treatment for non-severe pneumonia. Increasing treatment failure rates have been reported over a period of time, which could possibly be due to increasing minimum inhibitory concentrations of Streptococcus pneumoniae and Haemophilus influenzae for amoxicillin. Microbiological data show that this resistance can be overcome by increasing amoxicillin dosage. Based on this data, we examined whether we can improve the clinical outcome in non-severe pneumonia by doubling the dose of amoxicillin.

METHODS

A double blind randomised controlled trial was conducted in the outpatient departments of four large hospitals in Pakistan. Children aged 2-59 months with non-severe pneumonia were randomised to receive either standard (45 mg/kg/day) or double dose (90 mg/kg/day) oral amoxicillin for 3 days and then followed up for 14 days. Final outcome was treatment failure by day 5.

RESULTS

From September 2003 to June 2004, 876 children completed the study. 437 were randomised to standard and 439 to double dose oral amoxicillin. 20 (4.5%) children in the standard and 25 (5.7%) in the double dose group had therapy failure by day 5. Including the relapses, by day 14 there were 26 (5.9%) cumulative therapy failures with standard and 35 (7.9%) with double dose amoxicillin. These differences were not statistically significant (p = 0.55 and p = 0.29, respectively).

CONCLUSION

Clinical outcome in children aged 2-59 months with non-severe pneumonia is the same with standard and double dose oral amoxicillin. Non-severe pneumonia can be treated effectively and safely with a 3 day course of a standard dose.

The epidemiology of pneumococcal, meningococcal, and Haemophilus disease in the Middle East and North Africa (MENA) region--current status and needs

Information about the burden and epidemiological characteristics of meningitis and other invasive disease caused by Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis is of great value to healthcare decision makers to prioritize public health interventions. A group of regional experts in the Eastern Mediterranean and North African regions formed the MENA Vaccine-Preventable Diseases Regional Advisory Group to collate and discuss such information on an annual basis. This paper provides an up-to-date summary of the available epidemiological data regarding these pathogens in these regions. In doing so, it highlights the need for additional surveillance studies to better measure the burden of these diseases, as well as the potential impact of introduction of new vaccines against these pathogens.

Serotype distribution and antimicrobial susceptibility of S. pneumoniae causing invasive disease in Thai children younger than 5 years old, 2000-2005

In order to predict the potential benefit of pneumococcal conjugate vaccines (PCV), we evaluated the serotype coverage of the 7-, 9-, 11- and 13-valent PCV over the isolates causing invasive pneumococcal disease (IPD) in Thai children. One hundred and fifteen Streptococcus pneumoniae isolates from sterile sites in children younger than 5 years old between 2000 and 2005 were serotyped. The coverages of 7-, 9-, 11-, and 13-valent PCV were 69%, 73.8%, 73.8% and 85.7% in children younger than 2 years, and 73.9%, 77.4%, 77.4% and 87.8% in children younger than 5 years of age, respectively. 69.6% and 22.6% of the isolates were non-susceptible to penicillin and cefotaxime. 7-valent PCV covered 89% and 100% of penicillin and cefotaxime non-susceptible isolates.

What can children gain from pneumococcal conjugate vaccines?

In excess of 1 million young children die every year as a consequence of disease caused by Streptococcus pneumoniae, the vast majority in developing countries. Although the first vaccine against the Pneumococcus was produced before the First World War, licensure of the first vaccine with documented efficacy against severe infections in infants and young children did not occur until February 2000 in the United States. This conjugate vaccine consists of purified polysaccharide, from each of seven pneumococcal serotypes, chemically linked to a carrier protein. A high degree of efficacy of the new vaccine against potentially life-threatening infections has been shown in both poor and affluent countries. The vaccine's potential to protect from acute otitis media, however, is very limited, although encouraging indirect effects, such as reduced antibiotic prescriptions, have been reported. An inherent problem with the new pneumococcal conjugate vaccines is that, while more than 20 pneumococcal serotypes may cause invasive disease, only a more limited number of polysaccharides, 11 or so, can in practice be conjugated to carrier protein as part of a single vaccine formulation. Because of variation in the ranking of serotypes most commonly responsible for pneumococcal disease, by region, age and disease manifestation, compromise was required in selecting serotype-specific saccharides for inclusion.

CONCLUSION

Complex conjugate technology comes at a price, and the present costs keep most of the world's children far out of reach of an effective vaccine. However, the pneumococcal conjugate vaccine is a highly functional weapon against deadly pneumococcal infections, and strenuous efforts are needed to maximise its accessibility to children most at risk.

Effect of pneumonia case management on mortality in neonates, infants, and preschool children: a meta-analysis of community-based trials

Pneumonia still causes around two million deaths among children annually (20% of all child deaths). Any intervention that would affect pneumonia mortality is of great public health importance. This meta-analysis provides estimates of mortality impact of the case-management approach proposed by WHO. We were able to get data from nine of ten eligible community-based studies that assessed the effects of pneumonia case-management intervention on mortality; seven studies had a concurrent control group. Standardised forms were completed by individual investigators to provide information on study description, quality scoring, follow-up, and outcome (mortality) data with three age groups (<1 month, <1 year, 0-4 years) and two mortality categories (total and pneumonia-specific). Meta-analysis found a reduction in total mortality of 27% (95% CI 18-35%), 20% (11-28%), and 24% (14-33%) among neonates, infants, and children 0-4 years of age, respectively. In the same three groups pneumonia mortality was reduced by 42% (22-57%), 36% (20-48%), and 36% (20-49%). There was no evidence of publication bias and results were unaltered by exclusion of any study. A limitation of the included studies is that they were not randomised and, because of the nature of the intervention, could not be blinded. Community-based interventions to identify and treat pneumonia have a substantial effect on neonatal, infant, and child mortality and should be incorporated into primary health care.

Serotypes of respiratory tract isolates of Streptococcus pneumoniae from Jamaican children

BACKGROUND

Data are lacking on the pneumococcal serotypes present in many developing regions, including the Caribbean. We examined the serotypes of nasopharyngeal (NP) isolates of pneumococci obtained from Jamaican children.

METHODS

We obtained NP samples from children seen in the Emergency Department at the Bustamante Children's Hospital. The samples were transported to Canada for isolation and serotyping of pneumococci.

RESULTS

We obtained 94 isolates from 276 children; median age 3.4 years. The majority (57%) had symptoms of acute respiratory infection at the time of sampling. The main serotypes carried were 6B (20.5%), 19F (14.5%), and 14 (8.4%). Non-typable isolates accounted for 10.8% of the isolates. Fifty-nine per cent of the serotypes were present among the 11 being considered for candidate pneumococcal conjugate vaccines (95% CI 48-70%); the corresponding proportion present in the recently licensed 7-valent vaccine was 57% (95% CI 45-67%). A significant proportion of the serotypes found is absent from those to be included in future conjugate vaccines (P<0.0001; reference=85% expected serotype representation). Less than 5% of isolates were non-susceptible to penicillin (3.2%), cefotaxime-ceftriaxone (3.2%) and cefuroxime (3.2%), while 8.4% and 1.l% of isolates were resistant to trimethoprim-sulfamethoxazole and erythromycin respectively. There were three isolates with resistance to two or more classes of drug. These isolates were all resistant to penicillin (MIC 2 micro g/mL); the serotypes were 14, 23F, and 19F.

CONCLUSION

A significant proportion of the serotypes found is absent from those to be included in future conjugate vaccines.

Comparing pharmacokinetics of amoxicillin given twice or three times per day to children older than 3 months with pneumonia

For children with ambulatory pneumonia, the World Health Organization (WHO) recommends oral amoxicillin (15 mg/kg of body weight/dose) thrice daily (t.i.d.) or oral cotrimoxazole (4 mg of trimethoprim/kg/dose) twice daily (b.i.d.). The more frequent amoxicillin dosing may lead to compliance problems. To compare the pharmacokinetics and levels of amoxicillin in plasma in the current WHO acute respiratory infection recommendations with the 25-mg/kg/dose b.i.d. regimen, we performed a two-group parallel study of 66 children ages 3 to 59 months with pneumonia. Amoxicillin was given orally at 25 mg/kg/dose b.i.d. or 15 mg/kg/dose t.i.d. Amoxicillin concentrations were determined by high-performance liquid chromatography after the first dose on days 1 and 3. After the first dose on day 1, the mean area under the concentration-time curve (AUC) for amoxicillin after the 25-mg/kg dose was 54.7 versus 24.9 micro g. h/ml after the 15-mg/kg dose. After the first dose on day 3, the mean AUC was 44.1 versus 28.5 micro g. h/ml. All but two children had plasma amoxicillin concentrations above 0.5 micro g/ml for >50% of the dose interval on both days. Six children on day 1 and five children on day 3 had concentrations above 1.0 micro g/ml for <50% of the dose interval. On day 1, 16 of 27 children in the b.i.d. group and 11 of 26 children in the t.i.d. group had concentrations that were above 2.0 micro g/ml for <50% of the dose interval, and on day 3, 18 of 31 children in the b.i.d. group and 8 of 31 children in the t.i.d. group had concentrations that were above 2.0 micro g/ml for <50% of the dose interval. Amoxicillin b.i.d. is a feasible alternative for t.i.d. dosing. To lengthen the time above the MIC at higher concentration levels, a 30- to 40-mg/kg/dose b.i.d. should be considered instead of the 25 mg/kg/dose used in this study.

Population-based surveillance for hospitalized and ambulatory pediatric invasive pneumococcal disease in Santiago, Chile

BACKGROUND

Nine- and 11-valent pneumococcal conjugate vaccines under development may control pediatric pneumococcal disease in nonindustrialized countries. Because these vaccines are expensive, population-based surveillance of pneumococcal disease in children <36 months of age was undertaken in Santiago, Chile to provide health authorities with reliable data on the burden of invasive pneumococcal disease and causative serotypes, including those in outpatients with high fever.

METHODS

Automated blood culture machines were introduced into 9 hospitals that admit 85% of all hospitalized children in Santiago. Acutely ill pediatric febrile ambulatory patients are attended at 8 emergency rooms (ERs) and 36 urgent primary care services. After a 12-month pilot study in 3 ERs, health authorities collected blood cultures from children <36 months of age with high fever seen in the ER as standard practice. isolates were serotyped.

RESULTS

Blood cultures of 18 (1.2%) of 1,503 outpatients 6 to 35 months of age with high fever in the pilot study yielded S. In the ensuing 24 months 236 children <36 months old were hospitalized with invasive pneumococcal disease (incidence, 33.9 cases/10(5) children), and 188 bacteremias were detected among ambulatory ER patients with high fever (incidence, 27.0 cases/10(5) children). Although serotypes were similar among hospitalized and ambulatory cases (except 18C, which was more common in the latter), case fatality was 9.5% in hospitalized (21 of 236) 0% in ambulatory cases (0 of 188) (P = <0.0001). High level resistance to penicillin (25.8% vs 10.1%) and cefotaxime (19.5% vs 6.2%) was observed more often among pneumococcal isolates from hospitalized than among ambulatory cases (P < 0.001).

CONCLUSIONS

ER surveillance detected approximately one case of pneumococcal bacteremia among febrile ambulatory patients for each hospitalized invasive case. Because 71% of cases were caused by vaccine serotypes (and 87% by vaccine serogroups), 9- and 11-valent pneumococcal conjugate vaccines could prevent most invasive pediatric pneumococcal disease in Chile.

Clinical efficacy of co-trimoxazole versus amoxicillin twice daily for treatment of pneumonia: a randomised controlled clinical trial in Pakistan

AIMS

To compare the clinical efficacy of twice daily oral co-trimoxazole with twice daily oral amoxicillin for treatment of childhood pneumonia.

METHODS

Randomised controlled, double blind, multicentre study in outpatient departments of seven hospitals and in one community health service. A total of 1471 children (aged 2-59 months) with non-severe pneumonia were randomly assigned to 25 mg/kg amoxicillin (n = 730) or 4 mg/kg trimethoprim plus 20 mg/kg sulphamethoxazole (co-trimoxazole) (n = 741). Both medicines were given orally twice daily for five days.

RESULTS

Data from 1459 children were analysed: 725 were randomised to amoxicillin and 734 to co-trimoxazole. Treatment failure in the amoxicillin group was 16.1% compared to 18.9% in the co-trimoxazole group. Multivariate analysis showed that treatment failure was more likely in infants who had history of difficult breathing or those who had been ill for more than three days before presentation.

CONCLUSIONS

Both amoxicillin and co-trimoxazole were equally effective in non-severe pneumonia. Good follow up of patients is essential to prevent worsening of illness.

Bacterial meningitis in children: critical care needs

Acute bacterial meningitis (ABM) in children is associated with a high rate of acute complications and mortality, particularly in the developing countries. Most of the deaths occur during first 48 hours of hospitalization. Coma, raised intracranial pressure (ICP), seizures, shock have been identified as significant predictors of death and morbidity. This article reviews issues in critical care with reference to our experience of managing 88 children with ABM in PICU. Attention should first be directed toward basic ABCs of life-support. Children with Glasgow Coma Scale (GSC) score < 8 need intubation and supplemental oxygen. Antibiotics should be started, even without LP (contraindicated if focal neuro-deficit, papilledema, or signs of raised ICP). Raised ICP is present in most of patients; GCS < 8 and high blood pressure are good guides. Mannitol (0.25 gm/Kg) should be used in such patients. If there are signs of (impending) herniation short-term hyperventilation is recommended; prolonged hyperventilation (> 1 hour) must be avoided. Any evidence of poor perfusion, hypovolemia and/or hypotension needs aggressive treatment with normal saline boluses and inotropes, if necessary, to maintain normal blood pressure. Empiric fluid restriction is not justified. Seizures may be controlled with intravenous diazepam or lorazepam. Refractory status epilepticus may be treated with continuous diazepam (0.01-0.06) mg/kg/min) or midazolam infusion. Ventilatory support may be needed early for associated pneumonia, poor respiratory effort and/or coma, and occasionally to reduce work of breathing in shock. Provision of critical care to children with ABM may reduce the mortality significantly as experienced by us.

Implications of health care provision on acute lower respiratory infection mortality in Bangladeshi children

This study uses a geographic information system to evaluate the effects of health care provision on acute lower respiratory infection (ALRI) mortality in very young children in rural Bangladesh. Since 1988, an ALRI control program has been operating in a rural area of Bangladesh in an effort to decrease morbidity and mortality of children suffering from ALRI. ALRI-specific mortality data for very young children (<2 years of age) were obtained from a surveillance system of the area from 1988 to 1993. The ALRI mortality data were aggregated by clusters of households called baris. In order to avoid bias in the population size of haris, spatial moving averages of ALRI-specific death rates were calculated. The relationships between ALRI death rates and several environmental and health service provision variables were measured using regression analysis. The results show that the ALRI mortality rate was 54% lower in the community-based ALRI control program area than in a comparison area where there was no intervention. Greater access to allopathic practitioners was related to lower ALRI mortality rates while access to indigenous practitioners was related to higher mortality. In conclusion, the benefit of the community-based ALRI control program, using a simple case management strategy and improved access to allopathic practitioners, should be replicated in other rural areas of Bangladesh in an effort to reduce child ALRI mortality.

Treatment of acute otitis media - challenges in the era of antibiotic resistance

The last decade is characterized by the increase in antibiotic resistance among respiratory bacterial pathogens in the presence of only modest progress in the development of new antibacterial agents to overcome this resistance. A series of recent studies show clearly that the increased resistance among the main AOM pathogens (namely Streptococcus pneumoniae and Haemophilus influenzae) is associated with a dramatic decrease in bacteriologic response to antibiotic treatment, which in turn has an impact on clinical response. Thus, the individual patient is affected by the increasing antibiotic resistance. Moreover, the society as a whole is now also affected because the carriage and spread of antibiotic resistant AOM pathogens is remarkably impacted by antibiotic treatment. New studies show the remarkable ability of antibiotics to rapidly promote nasopharyngeal carriage and spread of antibiotic-resistant AOM pathogens. In these studies, the increase in carriage of antibiotic resistant S. pneumoniae is shown already after 3-4 days from initiation of antibiotic treatment and may last for weeks to months after treatment. Children carrying antibiotic-resistant organisms transmit those organisms to their family and to their day care centers and thus a vicious cycle is created in which increased antibiotic resistance with decreased response leads to increased antibiotic use, which in turn leads to further increase in resistance. New antibiotics are not likely to improve this situation. It is clear that the challenge in the next decade is to prevent AOM rather than to treat it. Efforts to prevent AOM include improved environmental factors, immunization with bacterial and viral vaccines and some creative measures such as prevention of colonization and attachment to epithelium of AOM pathogens. Whether these efforts will prove successful or, even if successful, will only modify the clinical and bacteriologic picture presenting new challenges, only time will tell.

Antimicrobial resistance in the tropics

Bacterial resistance to antimicrobial agents is an increasing problem in many areas of the tropics. In most countries there is little information available to determine the patterns of resistance in different pathogens, nor are local data available to influence prescribing. This paper will review the development of antimicrobial resistance in the tropics, consider the current priority problems, and suggest strategies that may be taken to improve the surveillance of resistance.

Distribution of capsular types and penicillin-resistance of strains of Streptococcus pneumoniae causing systemic infections in Argentinian children under 5 years of age. Streptococcus pneumoniae Working Group

Streptococcus pneumoniae (SPN) is the most common cause of invasive infections in children, with high levels of mortality in developing countries. An increase in frequency of penicillin-resistant strains is reported in most parts of the world. A study was undertaken in Argentina and 5 other countries of the region, to determine the type distribution and penicillin resistance rate of SPN isolated from invasive infections in children less than 5 years old. Between June 1994 and March 1996, a total of 505 SPN isolated from sterile sites were collected from 15 hospitals located in 9 cities of different geographic areas. Clinical and epidemiological data from 443 children were analyzed. Sixty five percent SPN were isolated from children less than 2 years old. Pneumonia was the clinical diagnosis in 58% of the cases, meningitis in 22%, and sepsis in 10.6%. Isolates were recovered from blood (51.2%), pleural fluid (22.7%), CSF (20.7%), and other sterile sites (5.4%). Thirty different pneumococcal capsular types were identified and the 10 most frequent in descending order were: 14, 5, 1, 6A/6B, 7F, 9V, 19F, 19A, 16F y 23F, representing 89.3% of the total. Overall, 13.1% of isolates showed intermediate resistance to penicillin while 11.3% showed high resistance. Lethality was 8.8%, without correlation with penicillin-resistance and/or type. These result should be used in selecting the optimal combination of specific types for a conjugate vaccine, useful in children less than 2 years old and for considering therapeutic strategies for invasive pneumococcal infections.

Nasal carriage in Vietnamese children of Streptococcus pneumoniae resistant to multiple antimicrobial agents

Resistance to antimicrobial agents in Streptococcus pneumoniae is increasing rapidly in many Asian countries. There is little recent information concerning resistance levels in Vietnam. A prospective study of pneumococcal carriage in 911 urban and rural Vietnamese children, of whom 44% were nasal carriers, was performed. Carriage was more common in children <5 years old than in those >/=5 years old (192 of 389 [49.4%] versus 212 of 522 [40.6%]; P, 0.01). A total of 136 of 399 isolates (34%) had intermediate susceptibility to penicillin (MIC, 0.1 to 1 mg/liter), and 76 of 399 isolates (19%) showed resistance (MIC, >1.0 mg/liter). A total of 54 of 399 isolates (13%) had intermediate susceptibility to ceftriaxone, and 3 of 399 isolates (1%) were resistant. Penicillin resistance was 21.7 (95% confidence interval, 7.0 to 67.6) times more common in urban than in rural children (35 versus 2%; P, <0.001). More than 40% of isolates from urban children were also resistant to erythromycin, trimethoprim-sulfamethoxazole, chloramphenicol, and tetracycline. Penicillin resistance was independently associated with an urban location when the age of the child was controlled for. Multidrug resistance (resistance to three or more antimicrobial agent groups) was present in 32% of isolates overall but in 39% of isolates with intermediate susceptibility to penicillin and 86% of isolates with penicillin resistance. The predominant serotypes of the S. pneumoniae isolates were 19, 23, 14, 6, and 18. Almost half of the penicillin-resistant isolates serotyped were serotype 23, and these isolates were often multidrug resistant. This study suggests that resistance to penicillin and other antimicrobial agents is common in carriage isolates of S. pneumoniae from children in Vietnam.

The contribution of specific pneumococcal serogroups to different disease manifestations: implications for conjugate vaccine formulation and use, part II

To assess whether certain serogroups of Streptococcus pneumoniae are preferentially associated with specific disease manifestations, we analyzed all recent pneumococcal disease studies and assessed the relative frequency of isolation of each serogroup by clinical site (as a proxy for different disease states). In all age groups, serogroups 1 and 14 were more often isolated from blood, and serogroups 6, 10, and 23 were more often isolated from cerebrospinal fluid (CSF); in young children, serogroups 3, 19, and 23 were more often isolated from middle ear fluid (MEF). Serogroups represented in conjugate vaccines were isolated slightly less frequently from CSF than from blood or MEF. Nonetheless, serogroups in the 9-valent conjugate vaccine formulation still comprised approximately 75% of pneumococcal isolates from the CSF of young children in Europe and in the United States and Canada. These analyses indicate that pneumococcal conjugate vaccines could potentially prevent a substantial proportion of episodes of bacteremic disease, pneumonia, meningitis, and otitis media, especially in young children.

Which pneumococcal serogroups cause the most invasive disease: implications for conjugate vaccine formulation and use, part I

We analyzed >70 recent data sets to compare the serogroups causing invasive pneumococcal disease (IPD) with those represented in conjugate vaccine formulations. Five to 8 and 10-11 serogroups comprise at least 75% of pneumococcal isolates from young children and older children/adults, respectively, in each geographic region. Serogroups in the 7-valent formulation (4, 6, 9, 14, 18, 19, and 23) cause 70%-88% of IPD in young children in the United States and Canada, Oceania, Africa, and Europe, and <65% in Latin America and Asia. Serogroups in the 9-valent formulation (7-valent+1, 5) cause 80%-90% of IPD in each region except Asia (66%). Serogroup 1 accounts for >6% of IPD in each region, including Europe, except the United States and Canada and Oceania. In contrast, several serogroups not found in 7-, 9-, and 11-valent conjugate formulations are significant causes of disease in older children/adults. Nevertheless, each conjugate formulation could prevent a substantial IPD burden in each region and age group.

Striking differences in the nasopharyngeal flora of healthy Angolan, Brazilian and Dutch children less than 5 years old

Community-acquired pneumonia from enteric gram-negative bacilli is more common in developing than in industrialized countries. We investigated the nasopharyngeal flora in healthy children from Angola, Brazil and The Netherlands to see whether enteric gram-negative bacilli are more often part of the commensal flora in developing countries. Nasopharyngeal specimens were collected from children aged between 4 months and 5 years in day-care centres and immunization clinics. Children who had received antibiotics or were malnourished were excluded. Brazilian and Angolan children had a higher number of household members than Dutch children (5.5 and 7 vs 3.9 mean number of household members, respectively) (p < 0.0001). Enteric and non-fermentative gram-negative bacilli were much more prevalent in Brazilian (50%) and Angolan (57%) children than in Dutch (4%) children (p < 0.0001). By univariate analysis, carriage of enteric gram-negative bacilli was associated with the number of household members (r = 0.26; p < 0.001). The high carriage rate of enteric gram-negative bacilli in children from Angola and Brazil may explain why enteric gram-negative bacilli are a common cause of pneumonia in developing countries.