Invasive pneumococcal disease associated with high case fatality in India

Global Case Fatality of Bacterial Meningitis During an 80-Year Period: A Systematic Review and Meta-Analysis

Importance

The impact of vaccination, antibiotics, and anti-inflammatory treatment on pathogen distribution and outcome of bacterial meningitis over the past century is uncertain.

Objective

To describe worldwide pathogen distribution and case fatality ratios of community-acquired bacterial meningitis.

Data Sources

Google Scholar and MEDLINE were searched in January 2022 using the search terms bacterial meningitis and mortality.

Study Selection

Included studies reported at least 10 patients with bacterial meningitis and survival status. Studies that selected participants by a specific risk factor, had a mean observation period before 1940, or had more than 10% of patients with health care-associated meningitis, tuberculous meningitis, or missing outcome were excluded.

Data Extraction and Synthesis

Data were extracted by 1 author and verified by a second author. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Random-effects models stratified by age (ie, neonates, children, adults), Human Development Index (ie, low-income or high-income countries), and decade and meta-regression using the study period's year as an estimator variable were used.

Main Outcome and Measure

Case fatality ratios of bacterial meningitis.

Results

This review included 371 studies performed in 108 countries from January 1, 1935, to December 31, 2019, describing 157 656 episodes. Of the 33 295 episodes for which the patients' sex was reported, 13 452 (40%) occurred in females. Causative pathogens were reported in 104 598 episodes with Neisseria meningitidis in 26 344 (25%) episodes, Streptococcus pneumoniae in 26 035 (25%) episodes, Haemophilus influenzae in 22 722 (22%), other bacteria in 19 161 (18%) episodes, and unidentified pathogen in 10 336 (10%) episodes. The overall case fatality ratio was 18% (95% CI, 16%-19%), decreasing from 32% (95% CI, 24%-40%) before 1961 to 15% (95% CI, 12%-19%) after 2010. It was highest in meningitis caused by Listeria monocytogenes at 27% (95% CI, 24%-31%) and pneumococci at 24% (95% CI, 22%-26%), compared with meningitis caused by meningococci at 9% (95% CI, 8%-10%) or H influenzae at 11% (95% CI, 10%-13%). Meta-regression showed decreasing case fatality ratios overall and stratified by S pneumoniae, Escherichia coli, or Streptococcus agalactiae (P < .001).

Conclusions and Relevance

In this meta-analysis with meta-regression, declining case fatality ratios of community-acquired bacterial meningitis throughout the last century were observed, but a high burden of disease remained.

Guidelines for Antibiotics Prescription in Critically Ill Patients

How to cite this article: Khilnani GC, Tiwari P, Mittal S, Kulkarni AP, Chaudhry D, Zirpe KG, et al. Guidelines for Antibiotics Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(S2):S104-S216.

Pneumococcal serotypes causing non-invasive pneumonia in adults from a South Indian tertiary care hospital and the impact of the newer conjugate vaccines

Background

Streptococcus pneumoniae is the leading cause of community-acquired pneumonia (CAP) in adults. Ageing, chronic conditions and comorbidities are important risk factors for pneumococcal pneumonia.

Purpose

There is lack of data on the pneumococcal serotypes causing non-invasive pneumonia in India. This study aims to determine the prevalent pneumococcal serotypes causing non-invasive pneumonia, the associated comorbidities, and the coverage of both the available pneumococcal vaccines in India and conjugate vaccines that are currently undergoing clinical trials.

Methods

A total of 280 subjects (aged >16 years) who had clinical symptoms correlating with radiological findings for non-invasive bacteremic pneumonia and microbiological evidence of S. pneumoniae between 2018 and 2020 were included. The clinical, demographic, radiological and microbiological findings were retrieved from the Hospital Information System (HIS).

Result

The common serotypes in order of prevalence were 19F, 9V, 23F, 6B, 11A, 13, 34, 10A, 19A and 6A. The predominant non-vaccine serotypes were 13, 34, 35B, 31 and 16F. The associated radiological findings were pneumonic consolidation and multi-lobar involvement. Other coinfected bacterial pathogens included H. influenzae, S. aureus, K. pneumoniae and P. aeruginosa.

Conclusion

The pneumococcal vaccines: PCV10/GSK, PCV10/SII, PCV13, PCV15, PCV20 and PPSV23 provide an overall serotype coverage of 36, 41, 47, 48, 61 and 69 %, respectively of S. pneumoniae causing non-invasive pneumonia in South India. Increasing catch-up vaccination using PCV10(SII) in pre-school children could have a more significant impact on reducing pneumococcal pneumonia in adults (>50 years) in terms of increased herd immunity at an affordable cost.

Pneumococcal Vaccine Recommendations for Old-Age Home Indian Residents: A Literature Review

Advancing age is accompanied by decreased immunity, poor health, and physiological changes, which render the elderly population highly susceptible to infectious diseases. We aim to identify the guidelines for pneumococcal vaccines in old-age facilities in India. We performed an extensive review of Indian literature (indexed and non-indexed publications) from 2010 to 2020 using search strings “Pneumococcal vaccine AND Recommendations AND India,” “Pneumococcal vaccine AND Guidelines AND India,” followed by a hand search to identify the most updated versions of recommendations. We reviewed immunization guidelines recommended by nine medical associations and societies in India—Association of Physicians of India (API), Geriatric Society of India (GSI), Indian Society of Nephrology (ISN), Mass Gathering Advisory Board Consensus Recommendation, Indian Medical Association (IMA), Indian Chest Society and National College of Chest Physicians (ICS-NCCP), Research Society for Study of Diabetes in India (RSSDI), Indian Association of Occupational Health Guidelines for Working Adults (IAOH), and API guidelines for immunization during COVID19 pandemic. All bodies recommend pneumococcal vaccines, sequence and preference of which depend on factors such as age, underlying conditions, and immune status. Integration of society recommendations and their implementation into public and private vaccination programs are required to promote adult immunization.

Systematic literature review of the disease burden and vaccination of pneumococcal disease among adults in select Asia-Pacific areas

INTRODUCTION

Pneumococcal diseases are common and cause significant morbidity and mortality, with higher rates especially in developing areas including many in the Asia-Pacific (AP) region. However, current strategies to prevent pneumococcal disease in adults are quite complicated and not well implemented among many AP areas, and vaccination coverage rates among adults are generally low or perceived as low in the region. Thus, this literature review's purpose was to summarize the disease burden and vaccination against pneumococcal diseases among adults in select AP areas (Australia, Hong Kong, India, Indonesia, South Korea, Malaysia, New Zealand, the Philippines, Singapore, Taiwan, Thailand, and Vietnam).

AREAS COVERED

This systematic review included published articles from January 2010 to August 2020 using MEDLINE/Embase. Grey literature websites were searched for national immunization programs and medical society vaccination recommendations from areas of interest. A total of 69 publications were identified.

EXPERT OPINION

In the AP region, pneumococcal disease burden and serotype prevalence are variable among adult populations, particularly among older adults. Data was provided primarily from countries with established national immunization programs (NIPs). Further research on the disease burden and emphasis on the benefits of vaccination in AP areas lacking pneumococcal vaccination programs is warranted.

Comparative genomics of invasive Streptococcus pneumoniae CC320/271 serotype 19F/19A before the introduction of pneumococcal vaccine in India

The emergence of multi drug resistant clone CC320 serotype19F/19A and their capsular (cps) antigenic variants due to selective pressures such as vaccine had been reported worldwide. Hence, it is important to identify the prevalent clones, sequence types and cps variants of serotype 19F/19A in India, where PCV13 has been recently introduced. Multi-locus sequence typing (MLST) was performed for all (n = 21) invasive S. pneumoniae isolates of serotype 19A (n = 5) and 19F (n = 16) collected between the years 2012 and 2018 from children less than 5 years. The genome characterization by whole genome sequencing for the Sequence types (STs) 320 and 271(n = 7) were performed and compared with another six Indian WGSs of similar STs available from the GPS platform. The predominant STs in the serotype 19F/19A study isolates were of CC320: ST 320, 236 and 271, associated with PMEN clone Taiwan^19F-14. The WGSs of CC320 study isolates showed high genomic similarity to the Taiwan^19F-14 clone, and the penicillin binding protein (PBP) amino acid sequence similarity was 100% for PBP1A, 93% for PBP 2B and 2X. Whilst PBP comparison with other global MDR ST320 strains revealed that the ST320 clones in India are of low-level penicillin resistance. The presence of a few ST320/19A/19F invasive isolates with high similarity to the Taiwan clone suggests slow and gradual expansion of Taiwan^19F-14 associated CC320 clones in India. Since serotype 19F/19A is covered by PCV13 vaccine, the expansion of 19F/19A cones with non-PCV13 vaccine serotype in India should be monitored.

Invasive Bacterial Infections in Subjects with Genetic and Acquired Susceptibility and Impacts on Recommendations for Vaccination: A Narrative Review

The WHO recently endorsed an ambitious plan, “Defeating Meningitis by 2030”, that aims to control/eradicate invasive bacterial infection epidemics by 2030. Vaccination is one of the pillars of this road map, with the goal to reduce the number of cases and deaths due to Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus agalactiae. The risk of developing invasive bacterial infections (IBI) due to these bacterial species includes genetic and acquired factors that favor repeated and/or severe invasive infections. We searched the PubMed database to identify host risk factors that increase the susceptibility to these bacterial species. Here, we describe a number of inherited and acquired risk factors associated with increased susceptibility to invasive bacterial infections. The burden of these factors is expected to increase due to the anticipated decrease in cases in the general population upon the implementation of vaccination strategies. Therefore, detection and exploration of these patients are important as vaccination may differ among subjects with these risk factors and specific strategies for vaccination are required. The aim of this narrative review is to provide information about these factors as well as their impact on vaccination against the four bacterial species. Awareness of risk factors for IBI may facilitate early recognition and treatment of the disease. Preventive measures including vaccination, when available, in individuals with increased risk for IBI may prevent and reduce the number of cases.

Serotype distribution and clinical characteristics associated with streptococcus pneumoniae among Chinese children and adults with invasive pneumococcal disease: a multicenter observational study

Few studies in China focused on serotypes of Streptococcus pneumoniae in patients with invasive pneumococcal disease (IPD). We aimed at investigating the serotype distribution for IPD-causing S. pneumoniae and vaccine coverage among Chinese children and adults. This was a multicenter, observational study to collect S. pneumoniae isolates from normal sterile sites and IPD-related clinical information among children and adults. Serotyping was performed by a Capsule-Quellung reaction test using type-specific antisera. The study collected a total of 300 eligible isolates (pediatric = 148, adult = 152) were serotyped in a central laboratory. The most prevalent serotypes were 19A (20.9%) and 23 F (20.3%) in the pediatric group; 3 (21.7%) and 19 F (11.8%) in the adult group. PCV10 had low-to-moderate serotype coverage rates for children (60.8%) and adults (34.2%). PCV13 and PPV23 had high coverage rates for children (89.9%, 93.2%) and adults (70.4%, 82.9%), respectively, Investigational PCVs including PCV15 and PCV20 had high estimated coverage rates in children (89.9%, 93.9%). The study identified 269 subjects with IPD reported as the primary diagnosis in the medical records. Sepsis (48/136, 35.3%) and pneumonia (48/133, 36.1%) had the highest occurrence in the pediatric and adult groups, respectively. Study findings showed that non-PCV7 S. pneumoniae 19A and 3 were the most prevalent serotypes in Chinese children and adults, respectively. High-valent vaccines had similar coverage rates and may have a greater potential in preventing IPD.

A systematic literature review on the prevalence and etiology of meningitis among critically ill and hospitalized patients in India

BACKGROUND

In India, owing to multiple factors, such as insufficient laboratory capacity, poor reporting systems due to limited access to healthcare facilities and limited disease surveillance programmes, the actual disease burden of meningitis is unknown and may be largely under-reported.

OBJECTIVE

A systematic literature review was performed to describe: (a) the prevalence of meningitis; and (b) its etiological pathogen across different regions, age groups and patients with comorbidities.

METHOD

A systematic literature search was conducted between 1990 and 2020 using PubMed and Google Scholar databases to identify Indian studies reporting the prevalence rates and etiology of meningitis. A total of 51 studies were included in the final analysis.

RESULTS

A total of 38 studies reported prevalence of meningitis and 21 studies reported data on the etiology of meningitis in India. These studies included mixed patient populations: (a) pyogenic meningitis; (b) meningitis in sick or hospitalized patients with tuberculosis, acute febrile encephalopathy syndrome, septicaemia, invasive pneumococcal disease or respiratory compromise; and (c) meningitis patients with comorbidities. The prevalence of confirmed bacterial meningitis in the pediatric population (0-14 years) ranged between 0.5% and 61.8%. A total of seven studies reported the prevalence of meningitis in patients of all age groups (0-75 years), with prevalence ranging between 8.68% and 78.85%. Cryptococcal meningitis was predominant in patients with positive HIV/AIDS, with a prevalence ranging between 2.09% and 53.1%. Streptococcus pneumoniae was found to be the predominant pathogen causing meningitis across different regions of India, with a frequency ranging from 4% to 61.8% in patients of all age groups.

CONCLUSION

This systematic literature review displayed the possible range of frequency of bacterial meningitis pathogens across a wide variety of age groups in different regions of India. Further studies are warranted to monitor meningitis cases, which may facilitate the development of prevention and treatment strategies in India.

Study of Invasive Pneumococcal Infection in Adults with Reference to Penicillin Resistance

Background:

Invasive pneumococcal infections often prove rapidly fatal, even where good medical treatment is readily available. In developed countries, up to 20% of people who contract pneumococcal meningitis die; however, in developing world, mortality is closer to 50%, even among hospitalized patients. The World Health Organization estimated 600,000–800,000 adult deaths each year from pneumococcal pneumonia, meningitis, and sepsis.

Aims:

This study aims to estimate isolation rate of invasive pneumococcal infection in adults, to determine the antimicrobial susceptibility profile of Streptococcus pneumoniae isolates and to study the associated risk factors.

Materials and Methods:

A total of 120 patients with suspected invasive infection such as meningitis, septicemia, and pleural effusion, were included in the study. Various clinical specimens such as pus, cerebrospinal fluid, and other sterile body fluids were processed for isolation and identification of S. pneumoniae. Kirby–Bauer disc diffusion method was performed to determine the antimicrobial susceptibility profile. Minimum inhibitory concentration test was performed to determine the penicillin resistance.

Results:

Of 120 patients, 40 (33.33%) cases were proven by culture to have an invasive pneumococcal infection. The most common clinical condition observed was meningitis followed by pneumonia with pleural effusion and sepsis. Pneumococcal isolates exhibited 40% resistance to cotrimoxazole and 12.73% to chloramphenicol. Two meningeal isolates exhibited penicillin resistance. Comorbidities observed in 21 (52.5%) cases were mainly Diabetes mellitus, smoking, and alcoholism.

Conclusions:

Invasive pneumococcal infection has poor prognosis and penicillin-resistant strains have become increasingly common. This study emphasizes the importance of judicious use of antibiotics, especially to refrain their use in mild self-limiting upper respiratory infections.

Clinical practice guidelines 2019: Indian consensus-based recommendations on pneumococcal vaccination for adults

Similar to the global scenario, pneumococcal diseases are a significant health concern in India. Pneumococcal diseases occur frequently among adults and are largely preventable through vaccines. Globally, several guidelines and recommendations are available for pneumococcal vaccination in adults. However, owing to wide variations in the disease burden, regulatory landscape, and health-care system in India, such global guidelines cannot be unconditionally implemented throughout the country. To address these gaps, the Indian Chest Society and National College of Chest Physicians of India jointly conducted an expert meeting in January 2019. The aim of the discussion was to lay down specific evidence-based recommendations on adult pneumococcal vaccination for the country, with a view to further ameliorate the disease burden in the country. This article presents an overview of the closed-door discussion by the expert members on clinical practice guidelines to be followed for adult pneumococcal vaccination in India.

Host genetic variability and pneumococcal disease: a systematic review and meta-analysis

Background

Pneumonia, sepsis, meningitis, and empyema due to Streptococcus pneumoniae is a major cause of morbidity and mortality. We provide a systemic overview of genetic variants associated with susceptibility, phenotype and outcome of community acquired pneumococcal pneumonia (CAP) and invasive pneumococcal disease (IPD).

Methods

We searched PubMed for studies on the influence of host genetics on susceptibility, phenotype, and outcome of CAP and IPD between Jan 1, 1983 and Jul 4, 2018. We listed methodological characteristics and when genetic data was available we calculated effect sizes. We used fixed or random effect models to calculate pooled effect sizes in the meta-analysis.

Results

We identified 1219 studies of which 60 studies involving 15,358 patients were included. Twenty-five studies (42%) focused on susceptibility, 8 (13%) on outcome, 1 (2%) on disease phenotype, and 26 (43%) on multiple categories. We identified five studies with a hypothesis free approach of which one resulted in one genome wide significant association in a gene coding for lincRNA with pneumococcal disease susceptibility. We performed 17 meta-analyses of which two susceptibility polymorphisms had a significant overall effect size: variant alleles of MBL2 (odds ratio [OR] 1·67, 95% confidence interval [CI] 1·04–2·69) and a variant in CD14 (OR 1·77, 95% CI 1·18–2·66) and none of the outcome polymorphisms.

Conclusions

Studies have identified several host genetics factors influencing risk of pneumococcal disease, but many result in non-reproducible findings due to methodological limitations. Uniform case definitions and pooling of data is necessary to obtain more robust findings.

Electronic supplementary material

The online version of this article (10.1186/s12920-019-0572-x) contains supplementary material, which is available to authorized users.

Perform or perish: laboratory optimization to avoid false negative blood cultures in pneumococcal bacteremia

We present the laboratory operations influencing the culture yield of pneumococci and suggest an alternate solution to the problem. Blood cultures of 136 adults and 19 pediatric patients were analyzed in two phases. In phase I, the laboratory operated only during weekdays but in phase II the laboratory provided 24-h services on all days. In phase I, successful bacterial isolation leading to testing of antimicrobial susceptibility was possible only in 51% of cases, while a significant 49% had failed to grow in subcultures due to autolysis resulting from delayed processing time. These false negative blood cultures were further confirmed as Streptococcus pneumoniae by commercial antigen tests. In phase II, we did not observe any false-negative results due to prompt subculturing protocols (p < 0.001). We also found that taking blood cultures on two occasions increases the yield by 46% among adults.

Pneumococcal vaccines

Streptococcus pneumoniae continues to take a heavy toll on childhood mortality and morbidity across the developing world. An estimated 10.6 million invasive pneumococcal diseases (IPDs) occur every year, with nearly 1 million deaths in children under 5 years of age. Introduction of vaccines in the childhood immunisation programme in developed world has brought down the incidence of the disease considerably. However, childhood immunocompromising illnesses including HIV have increased the risk of IPD several folds. There is also a growing concern on the increasing antibiotic resistance among these invasive strains to penicillin, other beta-lactams and macrolides, making treatment difficult and expensive. It is estimated that about 62% of IPD worldwide is caused by the 10 most common serotypes. Although the ranking of individual pneumococcal serotypes causing serious disease varies among nations, the 7-13 serotypes included in pneumococcal conjugate vaccines (PCVs) may prevent 50%-80% of all paediatric pneumococcal diseases globally. The World Health Organization has recommended the use of PCV-10/13 in the national immunisation programmes (NIPs) of developing countries. Four doses of PCV-13 have been recommended by the US Association of Pediatrics and Centers for Disease Control and Prevention, at intervals of each 2 months for the first 6 months and by the 12^th to 15^th months after birth. This is expected to reduce the morbidity and mortality associated with IPD and simultaneously decrease colonisation with circulating antibiotic-resistant strains in immunized communities. Nevertheless, continued surveillance of antimicrobial resistance in non-vaccine serotypes is necessary to prevent the resurgence of resistance. Other virulence factors which are not serotype specific also need to be studied to overcome the drawbacks of serotype-specific pneumococcal vaccines. PCV-13 was launched during May 2017 under the NIP of five Indian states with the highest pneumococcal diseases in the country and is expected to be rolled out in the other parts of the country in the coming days.

Invasive pneumococcal disease in Indian adults: 11 years' experience

PURPOSE

To investigate the epidemiology of invasive pneumococcal disease (IPD), prevalent serotypes, and pattern of antimicrobial resistance (AMR) in Indian adults.

METHODS

Prospective laboratory based surveillance of IPD was carried out in >18 years age group between January 2007 and July 2017, from a tertiary care hospital in South India. All Streptococcus pneumoniae culture positives from blood, CSF and sterile body fluids were characterized to identify the serotypes and AMR.

RESULTS

A total of 408 IPD cases were characterized in this study. The overall case fatality rate in this study was 17.8% (95% confidence interval (CI): 14.1, 22.4). Pneumonia (39%), meningitis (24.3%), and septicaemia (18.4%) were the most common clinical conditions associated with IPD. Serotypes 1, 3, 5, 19F, 8, 14, 23F, 4, 19A and 6B were the predominant serotypes in this study. Penicillin non-susceptibility was low with 6.4% CONCLUSION: Serotype data from this study helped in accurate estimation of pneumococcal conjugate vaccine-13 and pneumococcal polysaccharide vaccine-23 protective coverage against serotypes causing IPD in India as 58.7% (95% CI: 53.8, 63.4) and 67.4% (95% CI: 62.7, 71.8) respectively. Penicillin non-susceptibility in meningeal IPD cases is 27.4%. Empirical therapy for meningeal IPD must be cephalosporin in combination with vancomycin since cefotaxime non-susceptibility in meningeal IPD is 9.9.

Safety and immunogenicity of a 13-valent pneumococcal conjugate vaccine in adults 50 to 65 years of age in India: An open-label trial

Streptococcus pneumoniae infection is a major global public health concern in older adults, especially as life expectancy continues to increase in most countries, including India. Recently, a 13-valent pneumococcal conjugate vaccine (PCV13) with the ability to enhance immunity (immunologic memory) on natural exposure or revaccination has been shown to protect against community-acquired pneumonia and invasive pneumococcal disease in adults 65 years of age and older. An unconjugated 23-valent pneumococcal polysaccharide vaccine has been available for decades; however, data on protection against pneumonia are inconsistent. For the first time, a multicenter study has been conducted in India to assess the safety and immunogenicity of a single dose of PCV13 in adults aged 50 to 65 years. In this study, PCV13 elicited robust immune responses against all 13 pneumococcal serotypes as reflected by the magnitude of geometric mean fold rises (range, 6.6-102.7) in functional antibody levels from before to 1 month after vaccination. No serious adverse events occurred. These clinical trial findings support the safety and immunogenicity of PCV13 when administered to adults in India and indicate that a single dose of PCV13 has the potential to protect against vaccine-type pneumococcal disease in adults aged 50 to 65 years. ClinicalTrials.gov identifier: NCT02034877.

Outcomes of Critically Ill Patients Who Have Serotype 5 Invasive Pneumococcal Disease

PURPOSE

To determine whether invasive pneumococcal disease (IPD) due to serotype 5, which occurred as a local outbreak in 2006 to 2007, is associated with intensive care unit (ICU) admission, hospital mortality, or organ supports in those who are critically ill.

MATERIALS AND METHODS

Retrospective review of patients who presented with IPD to 2 tertiary hospitals in Vancouver, Canada, from July 2004 to June 2007. We compared patient characteristics, interventions, and outcomes between patients who had serotype 5 and other serotypes using bivariate and multivariate analyses.

RESULTS

A total of 149 patients had serotype 5 and 106 had nonserotype 5. Patients with serotype 5 were younger, had lower prevalence of comorbid diseases, and had higher rates of substance use than patients with nonserotype 5. There were no differences in chest tube placement for complications of pneumonia or in ICU admission. Frequency of necrotizing pneumonia and hospital mortality were lower in the serotype 5 group. For the 71 patients with IPD who were admitted to ICU, there was no difference in severity of illness, ICU length of stay, or ICU mortality between the groups. There was also no difference in organ supports except that the serotype 5 group was more likely to receive vasopressors.

CONCLUSION

Serotype 5 in patients who have IPD is associated with no difference in ICU admission but with increased use of vasopressors and lower hospital mortality.

Trends of vaccine-preventable diseases in Afghanistan from the Disease Early Warning System, 2009-2015

BACKGROUND

Afghanistan's public health system was neglected during decades of military and civil conflict, and trends in infectious disease occurrence remain poorly characterized. This study examines cyclical and long-term trends of six vaccine-preventable diseases: pneumonia, diarrhea, meningitis, typhoid, measles, and acute viral hepatitis.

METHODS

Using weekly data collected between 2009 and 2015 through Afghanistan's Disease Early Warning System, we calculated monthly case counts, and fit a Poisson regression with a Fourier transformation for seasonal cycles and dummy variables for year.

RESULTS

We found the greatest incidence of diarrhea and typhoid in the summer, pneumonia in the winter, and measles in the late spring. Meningitis and acute viral hepatitis did not demonstrate substantial seasonality. Rates of pneumonia and diarrhea were constant across years whereas rates of meningitis, typhoid, and acute viral hepatitis decreased. Measles incidence increased in 2015.

CONCLUSIONS

Communicable disease reporting systems can guide public health operations-such as the implementation of new vaccines, and permit evaluation of health interventions. For example, measles supplementary immunization activities in Afghanistan have not slowed long-term transmission of the disease, but decreases in typhoid fever and acute viral hepatitis are probably tied to improvements in sanitation in the country.

Prevalence of pneumococcal serotypes in adults ≥50 years of age

CONTEXT

Currently, majority of studies on antibiotic resistance and serotype prevalence in Streptococcus pneumoniae are in paediatric population and there is limited epidemiologic data pertaining to elderly Indian population.

AIMS

This study was undertaken to assess antibiotic resistance pattern and the coverage of the polysaccharide vaccine 23 (PPV23) in the elderly population.

SETTINGS AND DESIGN

This was a prospective 2-year pneumococcal surveillance study in patients with community-acquired pneumococcal infections of ≥50 years' age group on fifty isolates of S. pneumoniae.

MATERIALS AND METHODS

Antibiotic susceptibility by Kirby-Bauer disc diffusion method and minimum inhibitory concentration susceptibility testing by E-test method were performed for various antibiotics. All isolates were serotyped by the capsular Quellung method with commercial antisera.

RESULTS

All S. pneumoniae isolates were sensitive to penicillin and ceftriaxone. Non-susceptibility to levofloxacin, co-trimoxazole, erythromycin and clindamycin was noted as 16%, 74%, 10% and 6%, respectively. Prevalence of multidrug resistance in S. pneumoniae was observed as 6%. The most common serotypes observed in our study were 19A (14%), 8 (10%), 19F (8%), 3 (6%) and 9N (6%). PCV7, PCV10, PCV13 and PCV23 coverage was observed as 16%, 24%, 48% and 66%, respectively. The non-vaccine serotypes (NVTs) comprised 30% (n = 15) of the isolates.

CONCLUSIONS

Our study shows different antibiotic susceptibility patterns of S. pneumoniae as compared to other neighbouring regions in Asia. The modest coverage of S. pneumoniae serotypes by PPV23 vaccine and prevalence of diverse NVTs in adult population make it a challenging task to recommend further changes in the future vaccine.

Community-Acquired Pneumonia in the Asia-Pacific Region

Community-acquired pneumonia (CAP) is an important cause of mortality and morbidity worldwide. Aging population, dense urbanization, and poor access to health care make the Asia-Pacific region vulnerable to CAP. The high incidence of CAP poses a significant health and economic burden in this region. Common etiologic agents in other global regions including Streptococcus pneumoniae, Mycoplasma pneumoniae, Haemophilus influenzae, Chlamydophila pneumoniae, Staphylococcus aureus, and respiratory viruses are also the most prevalent pathogens in the Asia-Pacific region. But the higher incidence of Klebsiella pneumoniae and the presence of Burkholderia pseudomallei are unique to the region. The high prevalence of antimicrobial resistance in S. pneumoniae and M. pneumoniae has been raising the need for more prudent use of antibiotics. Emergence and spread of community-acquired methicillin-resistant S. aureus deserve attention, while the risk has not reached significant level yet in cases of CAP. Given a clinical and socioeconomic importance of CAP, further effort to better understand the epidemiology and impact of CAP is warranted in the Asia-Pacific region.

Pneumococcal vaccination

PURPOSE OF REVIEW

Pneumococcal diseases (invasive diseases, pneumonia, otitis media, and sinusitis) are among the most frequent preventable infectious diseases carrying a very high morbidity and case fatality rate worldwide. Pneumococcal vaccination is a key element to reduce the global burden of the disease in children and adult population. Our aim is to discuss current knowledge of the epidemiology of pneumococcal disease and pneumococcal vaccines.

RECENT FINDINGS

After the introduction of conjugate vaccines (PCV7 and PCV13), rates of pneumococcal diseases because of vaccine serotypes have decreased considerably among children in the vaccine target and among nonvaccinated children and adults. Results of the Community-Acquired Pneumonia Immunization Trial in Adults demonstrated 45.6% efficacy of PCV13 against the first episode of pneumonia, 45% against first-episode nonbacteremic pneumococcal pneumonia, and 75% against the first episode of invasive pneumococcal diseases in adults older than 65 years. Recommendations for pneumococcal vaccination have changed recently in both the United States and Europe.

SUMMARY

The changing epidemiology of pneumococcal diseases should be closely investigated to assess the effectiveness and the usefulness of the current vaccination policies, and to identify future directions for preventing pneumococcal infections.

Etiology of community acquired pneumonia among children in India: prospective, cohort study

Background

Childhood community acquired pneumonia (CAP) is a significant problem in developing countries, and confirmation of microbial etiology is important for individual, as well as public health. However, there is paucity of data from a large cohort, examining multiple biological specimens for diverse pathogens (bacteria and viruses). The Community Acquired Pneumonia Etiology Study (CAPES) was designed to address this knowledge gap.

Methods

We enrolled children with CAP (based on WHO IMCI criteria of tachypnea with cough or breathing difficulty) over 24 consecutive months, and recorded presenting symptoms, risk factors, clinical signs, and chest radiography. We performed blood and nasopharyngeal aspirate (NPA) bacterial cultures, and serology (Mycoplasma pneumoniae, Chlamydophila pneumoniae). We also performed multiplex PCR for 25 bacterial/viral species in a subgroup representing 20% of the cohort. Children requiring endotracheal intubation underwent culture and PCR of bronchoalveolar lavage (BAL) specimens.

Findings

We enrolled 2345 children. NPA and blood cultures yielded bacteria in only 322 (13.7%) and 49 (2.1%) children respectively. In NPA, Streptococcus pneumoniae (79.1%) predominated, followed by Haemophilus influenzae (9.6%) and Staphylococcus aureus (6.8%). In blood, S. aureus (30.6%) dominated, followed by S. pneumoniae (20.4%) and Klebsiella pneumoniae (12.2%). M. pneumoniae and C. pneumoniae serology were positive in 4.3% and 1.1% respectively. Multiplex PCR in 428 NPA specimens identified organisms in 422 (98.6%); of these 352 (82.2%) had multiple organisms and only 70 (16.4%) had a single organism viz. S. pneumoniae: 35 (50%), Cytomegalovirus (CMV): 13 (18.6%), Respiratory Syncytial Virus (RSV): 9 (12.9%), other viruses: 6 (8.7%), S. aureus: 5 (7.1%), and H. influenzae: 2 (2.9%). BAL PCR (n = 30) identified single pathogens in 10 (S. pneumoniae–3, CMV–3, S. aureus–2, H. influenzae–2) and multiple pathogens in 18 children. There were 108 (4.6%) deaths. The pattern of pathogens identified did not correlate with pneumonia severity or mortality.

Conclusions

The majority of children with CAP have multiple pathogens (bacteria and viruses). S. pneumoniae and S. aureus predominate in NPA and blood respectively. CMV and RSV were the dominant respiratory viruses in NPA and BAL. The presence of multiple pathogens, especially organisms associated with nasopharyngeal carriage, precludes confirmation of a causal relationship in most cases.

Pneumococcal infection in adults: burden of disease

To overview the present global burden of pneumococcal disease is important because new preventive measures such as the pneumococcal conjugate vaccine 13 are currently being evaluated. Pneumococcal disease is roughly divided into non-invasive and invasive disease. The burden of non-invasive pneumococcal disease in adults is mainly determined by community-acquired pneumonia. Pneumococcal pneumonia has high incidence rates and carries a high mortality risk, especially in the elderly. Within the cluster of invasive pneumococcal diseases, pneumonia also represents the most common infectious source. Incidence and mortality rates of both non-invasive and invasive disease have changed as a result of pneumococcal vaccination in children. However, especially elderly patients with comorbidities remain vulnerable to morbidity and mortality caused by pneumococcal disease. The current review summarizes the current knowledge on the epidemiology including outcome of the main clinical forms of pneumococcal disease, with a special focus on elderly patients. Furthermore, the economic burden and future vaccine strategies are briefly discussed.

Pneumococcal serotype diversity among adults in various countries, influenced by pediatric pneumococcal vaccination uptake

Streptococcus pneumoniae serotypes differ in clinical manifestations among adults. Indirect effects of pediatric use of pneumococcal conjugate vaccines (PCVs) affect rates of adult serotype-specific invasive pneumococcal disease (IPD). To characterize PCV effect on adult serotype patterns, we reviewed the literature for differences in proportions and incidence matching the 23-valent pneumococcal polysaccharide vaccine (PPSV23) and 13-valent PCV within specified geographic and time conditions. For adult IPD serotype distribution before widespread pediatric PCV7 use, the median differential between the 23 and 13 serotypes was 16.3% in the core analysis. After pediatric PCV7 adoption, the median differential was 24.4% (P < .003).The median differential in IPD incidence among adults was 5.6 cases per 100 000 population before pediatric PCV7 use and 6.4 afterward (P = .52). The differential for the serotypes in alternate vaccines helps explain recent national recommendations for one or both vaccines in various populations. These differences may widen further, with more extensive pediatric uptake of higher-valence PCVs.