Seasonal distribution of otitis media pathogens among Costa Rican children

Seasonality of antimicrobial resistance rates in respiratory bacteria: A systematic review and meta-analysis

BACKGROUND

Antimicrobial resistance (AMR) rates may display seasonal variation. However, it is not clear whether this seasonality is influenced by the seasonal variation of infectious diseases, geographical region or differences in antibiotic prescription patterns. Therefore, we assessed the seasonality of AMR rates in respiratory bacteria.

METHODS

Seven electronic databases (Embase.com, Medline Ovid, Cochrane CENTRAL, Web of Science, Core Collection, Biosis Ovid, and Google Scholar), were searched for relevant studies from inception to Jun 25th, 2019. Studies describing resistance rates of Streptococcus pneumoniae and Haemophilus influenzae were included in this review. By using random-effects meta-analysis, pooled odd ratios of seasonal AMR rates were calculated using winter as the reference group. Pooled odd ratios were obtained by antibiotic class and geographical region.

RESULTS

We included 13 studies, of which 7 were meta-analyzed. Few studies were done in H. influenzae, thus this was not quantitively analyzed. AMR rates of S. pneumoniae to penicillins were lower in other seasons than in winter with pooled OR = 0.71; 95% CI = 0.65-0.77; I2 = 0.0%, and to all antibiotics with pooled OR = 0.68; 95% CI = 0.60-0.76; I2 = 14.4%. Irrespective of geographical region, the seasonality of AMR rates in S. pneumoniae remained the same.

CONCLUSION

The seasonality of AMR rates could result from the seasonality of infectious diseases and its accompanied antibiotic use.

Healthcare-seeking behaviour of primary caregivers for acute otitis media in children aged 6 months to <30 months in Panama: results of a cross-sectional survey

BACKGROUND

Acute otitis media (AOM) is the most common bacterial childhood infection. However, caregivers with children having mild episodes often do not seek healthcare services, which may lead to an under-appreciation of the disease experienced by the community. The objectives of this survey were to estimate the proportion of primary caregivers who went to a healthcare facility when they suspected that their child aged 6 to <30 months was having an AOM episode during the past 6 months and to assess what factors influenced their decision.

METHODS

This observational, cross-sectional survey of primary caregivers (≥18 years), with at least one child aged 6 to <30 months was performed in 19 healthcare facilities in Panama (March to May 2013). A 28-item paper questionnaire was administered to assess demographic data, AOM symptoms, as well as potential healthcare-seeking behaviour and factors influencing this behaviour. Potential confounding effects were individually assessed using Chi-squared or Cochran-Mantel-Haenszel tests, and all together in logistic regression models.

RESULTS

The total number of eligible participants was 1330 (mean age 28.5 ± 8.0 years). Of these, 245 participants had at least one child whom they suspected had an AOM episode during the past 6 months. Of the 245 participants, 213 (86.9%) sought healthcare at a facility. Several factors were associated with healthcare usage: perceived severity of illness (p = 0.001), occupational status of the caregiver (p = 0.002), household income (p = 0.016) and length of time since the last suspected AOM episode (p = 0.032).

CONCLUSIONS

When confronted with a child with obvious symptoms of AOM, the majority of caregivers reported seeking healthcare. This behaviour appeared to be associated with factors related to the severity of the illness, the length of time since the last episode, as well as with the income and occupational status of the caregivers themselves. As many episodes of AOM present with non-specific respiratory symptoms, our results apply only to caregivers who were confronted with children with an obvious symptom.

Non-typeable Haemophilus influenzae, an under-recognised pathogen

Non-typeable Haemophilus influenzae (NTHi) is a major cause of mucosal infections such as otitis media, sinusitis, conjunctivitis, and exacerbations of chronic obstructive pulmonary disease. In some regions, a strong causal relation links this pathogen with infections of the lower respiratory tract. In the past 20 years, a steady but constant increase has occurred in invasive NTHi worldwide, with perinatal infants, young children, and elderly people most at risk. Individuals with underlying comorbidities are most susceptible and infection is associated with high mortality. β-lactamase production is the predominant mechanism of resistance. However, the emergence and spread of β-lactamase-negative ampicillin-resistant strains in many regions of the world is of substantial concern, potentially necessitating changes to antibiotic treatment guidelines for community-acquired infections of the upper and lower respiratory tract and potentially increasing morbidity associated with invasive NTHi infections. Standardised surveillance protocols and typing methodologies to monitor this emerging pathogen should be implemented. International scientific organisations need to raise the profile of NTHi and to document the pathobiology of this microbe.

Panel 5: Microbiology and immunology panel

OBJECTIVE

The objective is to perform a comprehensive review of the literature from January 2007 through June 2011 on the virology, bacteriology, and immunology related to otitis media.

DATA SOURCES

PubMed database of the National Library of Medicine.

REVIEW METHODS

Three subpanels with co-chairs comprising experts in the virology, bacteriology, and immunology of otitis media were formed. Each of the panels reviewed the literature in their respective fields and wrote draft reviews. The reviews were shared with all panel members, and a second draft was created. The entire panel met at the 10th International Symposium on Recent Advances in Otitis Media in June 2011 and discussed the review and refined the content further. A final draft was created, circulated, and approved by the panel.

CONCLUSION

Excellent progress has been made in the past 4 years in advancing an understanding of the microbiology and immunology of otitis media. Advances include laboratory-based basic studies, cell-based assays, work in animal models, and clinical studies.

IMPLICATIONS FOR PRACTICE

The advances of the past 4 years formed the basis of a series of short-term and long-term research goals in an effort to guide the field. Accomplishing these goals will provide opportunities for the development of novel interventions, including new ways to better treat and prevent otitis media.

Antimicrobial resistance surveillance systems: Are potential biases taken into account?

BACKGROUND

The validity of surveillance systems has rarely been a topic of investigation.

OBJECTIVE

To assess potential biases that may influence the validity of contemporary antimicrobial-resistant (AMR) pathogen surveillance systems.

METHODS

In 2008, reports of laboratory-based AMR surveillance systems were identified by searching Medline. Surveillance systems were appraised for six different types of bias. Scores were assigned as '2' (good), '1' (fair) and '0' (poor) for each bias.

RESULTS

A total of 22 surveillance systems were included. All studies used appropriate denominator data and case definitions (score of 2). Most (n=18) studies adequately protected against case ascertainment bias (score = 2), with three studies and one study scoring 1 and 0, respectively. Only four studies were deemed to be free of significant sampling bias (score = 2), with 17 studies classified as fair, and one as poor. Eight studies had explicitly removed duplicates (score = 2). Seven studies removed duplicates, but lacked adequate definitions (score = 1). Seven studies did not report duplicate removal (score = 0). Eighteen of the studies were considered to have good laboratory methodology, three had some concerns (score = 1), and one was considered to be poor (score = 0).

CONCLUSION

Contemporary AMR surveillance systems commonly have methodological limitations with respect to sampling and multiple counting and, to a lesser degree, case ascertainment and laboratory practices. The potential for bias should be considered in the interpretation of surveillance data.

Streptococcus pneumoniae serotypes isolated from the middle ear fluid of Costa Rican children following introduction of the heptavalent pneumococcal conjugate vaccine into a limited population

BACKGROUND

The heptavalent pneumococcal conjugate vaccine (PCV-7) was introduced in high risk children and into the private market in Costa Rica in 2004 (<5% annual birth cohort). The aim of this study was to compare the Streptococcus pneumoniae serotype (ST) distribution, antibiotic resistance patterns and potential coverage before and after partial introduction of PCV-7.

METHODS

A comparison between the S. pneumoniae isolates obtained and serotyped from the middle ear fluid (MEF) of Costa Rican children with otitis media between years 1999 and 2003 (before PCV-7 usage) and those isolates obtained from 2004 to 2008.

RESULTS

A total of 145 and 218 MEF S. pneumoniae were serotyped between years 1999 and 2003 and 2004 and 2008, respectively. Considering a 19F outbreak observed between years 1999 and 2003, the following statistically significant changes in serotype distribution were detected between 1999 and 2003 and 2004 and 2008: ST 3: 4.8-12.8% (P=0.01); ST 11A: 0-4.1% (P=0.01); ST 14: 3.5-21.1% (P<0.001) and ST 19F: 52.4-18.3% (P<0.05). Comparison of the two study periods demonstrated that during 2004 and 2008 a statistically significant decrease in penicillin non-susceptible serotypes (36.2-20.4% [P=0.003]) and a statistically significant increase in trimethoprim-sulfametoxazole resistant serotypes (54.9-68.5%, respectively [P=0.03]) was observed. Potential pneumococcal vaccines coverage between 1999 and 2003 and between 2004 and 2008 were: for PCV-7: 77.2-60.5%, respectively (P=0.001); for the 10-valent conjugated vaccine (PCV-10): 78.6-61.4%, respectively (P=0.0008) and for the 13-valent conjugated vaccine (PCV-13): 84.8-79.3%, respectively (P=0.2).

CONCLUSIONS

Changes in the serotype distribution and antimicrobial susceptibility of MEF S. pneumoniae have been observed in Costa Rican children with OM. Because of the limited use of PCV-7 during the study period, these changes probably cannot be attributed to PCV-7 use. Between 2004 and 2008, PCV-13 offered the highest potential vaccine coverage.

Annual temperature and the prevalence of frequent ear infections in childhood

OBJECTIVES

The aim of this study was to determine if changes in annual temperature influence the prevalence of frequent otitis media (FOM) and respiratory allergy in children.

METHODS

Annual prevalence data for FOM (defined as 3 or more ear infections per year), respiratory allergy, and seizures (nonrespiratory, control condition) in children were extracted from the National Health Interview Survey for 1998 to 2006. Average US annual temperatures for the same period were recorded from the Environmental Protection Agency. Complex samples logistic regression analyses were performed to identify possible correlations between annual temperature and each of the 3 disease conditions, controlling for age and sex.

RESULTS

A total of 113,067 children were studied (mean age, 8.6 years; 51.1% girls). Overall prevalences (±95% confidence interval) were 6.3% ± 0.2%, 11.8% ± 0.2%, and 0.7% ± 0.1% for FOM, respiratory allergy, and seizures (nonrespiratory, control condition), respectively. Average annual temperatures ranged from 53.64°F to 55.09°F. Regression analysis found that annual temperature did not influence the prevalence of FOM (P = .681); male sex and younger age were associated with a higher prevalence of FOM (P = .025 and P < .001, respectively). Similarly, annual temperature did not influence prevalence of respiratory allergy (P = .883); male sex and increasing age were associated with a higher prevalence of respiratory allergy (both P < .001). Annual temperature and sex did not influence seizure prevalence; however, increasing age was negatively associated.

CONCLUSIONS

Changes in average annual temperature do not appear to influence the prevalence of otitis media or respiratory allergy. This negative finding suggests that although global warming continues to affect our environment, childhood otolaryngologic disease prevalence may not be directly influenced.

The impact of the heptavalent pneumococcal conjugate vaccine on the epidemiology of acute otitis media complicated by otorrhea

BACKGROUND

The heptavalent pneumococcal conjugate vaccine (PCV7) has a considerable effect on the epidemiology of pneumococcal disease. The aim of this observational hospital-based study was to examine the effect of the PCV7 (introduced in our settings in 2004) on the epidemiology of spontaneously draining acute otitis media.

METHODS

Results of all middle ear fluid cultures (n = 3446) obtained from children with acute otitis media complicated with otorrhea before the introduction of immunization (between 2000 and 2003) were compared with those (n = 2134) obtained during a similar post-PCV7 period (between 2005 and 2008). Results of cultures obtained between 2006 and 2008 were examined prospectively, whereas those obtained in previous years were retrospectively reviewed.

RESULTS

Following PCV7 immunization, the rates of otorrhea visits per 10,000 emergency department visits decreased by 38% from 133 to 83 (95% confidence interval of the difference, 42-53; P < 0.001), mainly as a result of the decrease in the incidence of pneumococcal disease (48% decrease-25 vs. 13 per 10,000 emergency department visits; P < 0.001). Otorrhea due to Haemophilus influenzae decreased by 20% (20-16 per 10,000 visits; P < 0.001). Serotype 19A accounted for 1 of 47 (2%) pneumococcal strains in 2006, for 5 of 34 (15%) in 2007, and for 13 of 53 (25%) in 2008 (P for trend: 0.001). In the postvaccine years, penicillin-resistant pneumococcal strains (minimum inhibitory concentration ≥ 2 μg/mL) increased from 4% to 13% (P < 0.001). However, the proportion of pneumococci resistant to macrolides decreased (44% vs. 35%; P = 0.01).

CONCLUSIONS

After the introduction of immunization, otorrhea incidents decreased considerably, mainly because of the decrease in pneumococcal disease. H. influenzae is now the predominant organism. Serotype 19A has increased significantly and is the most common nonvaccine pneumococcal serotype. Penicillin resistance has increased in recent years.

Poor adherence to antibiotic prescribing guidelines in acute otitis media--obstacles, implications, and possible solutions

Many countries now have guidelines on the clinical management of acute otitis media. In almost all, the public health goal of containing acquired resistance in bacteria through reduced antibiotic prescribing is the main aim and basis for recommendations. Despite some partial short-term successes, clinical activity databases and opinion surveys suggest that such restrictive guidelines are not followed closely, so this aim is not achieved. Radical new solutions are needed to tackle irrationalities in healthcare systems which set the short-term physician-patient relationship against long-term public health. Resolving this opposition will require comprehensive policy appraisal and co-ordinated actions at many levels, not just dissemination of evidence and promotion of guidelines. The inappropriate clinical rationales that underpin non-compliance with guidelines can be questioned by evidence, but also need specific developments promoting alternative solutions, within a framework of whole-system thinking. Promising developments would be (a) physician training modules on age-appropriate analgesia and on detection plus referral of rare complications like mastoiditis, and (b) vaccination against the most common and serious bacterial pathogens.

Otitis media across nine countries: disease burden and management

OBJECTIVE

To assess the perceived disease burden and management of otitis media (OM) among an international cohort of experienced physicians.

METHODS

A cross-sectional survey conducted in France, Germany, Spain, Poland, Argentina, Mexico, South Korea, Thailand and Saudi Arabia. Face-to-face interviews conducted with 1800 physicians (95% paediatricians, 5% family practitioners).Main outcome measures were the perceived burden on clinical practice (number of cases, complications and referrals) and first- and second-line management strategies for OM. Results are expressed as mean and range across the nine countries over three continents.

RESULTS

Respondents estimated an average annual caseload of 375 (range 128-1003) children under 5 years of age with OM; 54% (range 44-71%) with an initial episode and 38% (range 27-54%) with recurrent OM (ROM). OM with complications was estimated to be approximately 20 (range 7-49) cases per year and an estimated 15% (8-41%) of children with OM was recalled as needing specialist referral. There was high awareness of Streptococcus pneumoniae and Haemophilus influenzae as causative bacterial pathogens: 77% (range 65-91%) and 74% (range 68-83%), respectively, but less recognition of non-typeable H. influenzae (NTHi); 59% (range 45-67%). Although concern over antimicrobial resistance was widespread, empirical treatment with antibiotics was the most common first-line treatment (mean 81%, range 40-96%). The burden of disease is substantial enough that many physicians would consider vaccination to prevent OM (mean score 5.1, range 4.3-6.2 on 1-7 scale).

CONCLUSIONS

This large, multinational survey shows that OM remains a significant burden for clinical practice. Despite awareness of shortcomings, antimicrobial therapy remains the most frequent treatment for OM.

Surveillance for antimicrobial resistant organisms: potential sources and magnitude of bias

Surveillance has been recognized as a fundamental component in the control of antimicrobial- resistant infections. Although surveillance data have been widely published and utilized by researchers and decision makers, little attention has been paid to assessment of their validity. We conducted this review in order to identify and explore potential types and magnitude of bias that may influence the validity or interpretation of surveillance data. Six main potential areas were assessed. These included bias related to use of inadequate or inappropriate (1) denominator data, (2) case definitions, and (3) case ascertainment; (4) sampling bias; (5) failure to deal with multiple occurrences, and (6) those related to laboratory practice and procedures. The magnitude of these biases varied considerably for the above areas within different study populations. There are a number of potential biases that should be considered in the methodological design and interpretation of antimicrobial-resistant organism surveillance.

Potential contribution by nontypable Haemophilus influenzae in protracted and recurrent acute otitis media

BACKGROUND

Characterization of acute otitis media (AOM) caused by nontypable Haemophilus influenzae (NTHi) is important, particularly in view of the efforts to develop vaccines against NTHi. To characterize NTHi AOM a large database of culture-positive AOM cases was analyzed.

METHODS

All culture-positive AOM episodes (NTHi, Streptococcus pneumoniae, Moraxella catarrhalis, and Streptococcus pyogenes) in children <5 years old from 1999 through 2006, processed in our center were included. One isolate was counted per episode (< or = 30 days). Demographic and clinical data were retrieved from charts or by telephone interviews. Multivariable regression analysis models were used.

RESULTS

Twelve thousand eight hundred twenty-three (8145 culture-positive) episodes were included. NTHi was recovered in 4928 episodes; S. pneumoniae in 4399 episodes, M. catarrhalis in 499, and S. pyogenes in 447 episodes. Independent risk factors for NTHi AOM (in culture-positive episodes) were: winter (odds ratio [OR]: 1.2, 95% confidence interval [CI]: 1.05-1.33, P = 0.006); bilateral AOM (OR: 1.26, 95% CI: 1.12-1.42, P < 0.001); >3 previous AOM episodes (OR: 1.27, 95% CI: 1.11-1.47, P = 0.001); and antibiotic consumption in previous month (OR: 1.3, 95% CI: 1.15-1.46, P < 0.001). ORs for these variables remained significant when the analysis was conducted on single-pathogen AOM only. For both NTHi and S. pneumoniae, risk factors for mixed episodes were older age and bilateral AOM.

CONCLUSION

NTHi AOM is characterized by higher occurrence in winter, bilaterality, recurrence, and previous antibiotic treatment compared with that caused by S. pneumoniae. These findings are in agreement with data associating NTHi with protracted or recurrent morbidity. The finding that S. pneumoniae and NTHi mixed episodes are more likely to occur in older children and in bilateral AOM suggests that interaction between these 2 pathogens contributes to chronicity or complexity of AOM.

Microbiology of otitis media: a moving target

The microbiology of acute otitis media (AOM) is linked to the nasopharyngeal commensal flora. This respiratory ecosystem undergoes various selective pressures, such as antibiotic consumption and vaccine use. Socio-economic conditions also influence the bacterial composition of the nasopharynx. Streptococcus pneumoniae, non-encapsulated Haemophilus influenzae, Moraxella catarrhalis, and group A Streptococcus are the leading causes of bacterial AOM worldwide. This paper will discuss the causes and consequences of recent shifts in the underlying microbiology of AOM.