Particularities of bacterial ecology of acute otitis media in an African subtropical country (Cote d'Ivoire)

BACKGROUND: Acute otitis media (AOM) is the commonest infectious disease of childhood. Its treatment is based on a probabilistic antibiotic therapy. OBJECTIVE: To determine the prevalence of different bacteria responsible for AOM in children in Abidjan (C?te d'Ivoire). MATERIALS AND METHODS: This is a prospective study, between November 2002 and August 2003. To identify bacterial isolates, 60 children under 15 years old with AOM were enrolled. In 52 cases, the sample was recovered by aspiration of a spontaneous otorrhea and in eight cases, it was taken by paracentesis. Nasopharyngeal swabs were cultured. Antibiotic susceptibility tests were performed on isolates. RESULTS: 75% of children were under 24 months of age. Pseudomonas aeruginosa was recovered in 31.8% of cases followed by Streptococcus pneumoniae (21%), Proteus (7.4%) and Staphylococcus (6.2%). The rate of penicillin-nonsusceptible S. pneumoniae (NSSP) was 11.8%. Resistance to erythromycin was 6%. For Pseudomonas, resistances to antibiotics were 35.5% to ceftazidim and 16% to pefloxacin, respectively, but all the strains were sensible to colistin, iminepem and ciprofloxacin. CONCLUSION: These data can modify therapeutic approaches for treatment of AOM in our country. This study should encourage surveillance of AOM microbiology.     

Antibody responses to the outer membrane protein P6 of non-typeable Haemophilus influenzae and pneumococcal capsular polysaccharides in otitis-prone children

Acute otitis media (AOM) is a common infectious disease in children. Some children experience recurrent episodes of AOM. Recent investigations demonstrate antigen-specific immunological deficiencies in children prone to AOM. In the present study, the immune responses to non-typeable Haemophilus influenzae (NTHi) and Streptococcus pneumoniae (S. pneumoniae) were further investigated in otitis-prone children and normal children. Forty-eight percent of otitis-prone children exhibited reduced IgG2 levels to S. pneumoniae and 55% exhibited reduced IgG levels to NTHi. These data suggest that otitis proneness appears to be related to numerous immunological derangements. Pathogen-specific antibodies are a reliable measure of otitis proneness.     

Management of acute otitis media in an era of increasing antibiotic resistance

Development of resistance to available antimicrobial agents has been identified in every decade since the introduction of the sulfonamides in the 1930s. Current concerns for management of acute otitis media (AOM) are multi-drug resistant Streptococcus pneumoniae and beta-lactamase producing Haemophilus influenzae and Moraxella catarrhalis. In the USA, amoxicillin remains the drug for choice for AOM. Increasing the current dose to 80 mg/kg/day in two doses provides increased concentrations of drug in serum and middle ear fluid and captures additional resistant strains of S. pneumoniae. For children who fail initial therapy with amoxicillin an expert panel convened by the Centers for Disease Control and Prevention suggested amoxicillin-clavulanate, cefuroxime axetil or intramuscular ceftriaxone. To protect the therapeutic advantage of antimicrobial agents used for AOM, it is important to promote judicious use of antimicrobial agents and avoid uses if it is likely that viral infections are the likely cause of the disease, to implement programs for parent education and to increase the accuracy of diagnosis of AOM. Conjugate polysaccharide pneumococcal vaccines are currently in clinical trial; early results indicate protective levels of antibody can be achieved with a three dosage schedule beginning at 2 months of age. Finally, alternative medicine remedies may be of value for some infectious diseases including AOM; garlic extract is bactericidal for the major bacterial pathogens of AOM but is heat- and acid-labile and loose activity when cooked or taken by mouth.     

Factors associated with clinical outcomes in acute otitis media

Acute otitis media (AOM) is a common disease in childhood. If predictors of outcome in AOM were known, it would be possible to individualize therapy. Our aim was to identify factors that predict the outcome in AOM. We enrolled 368 children with AOM (ages, 10 to 86 months). The severity of symptoms and the severity of tympanic membrane changes were graded with a scoring system. Nasopharyngeal colonization with middle ear pathogens was determined on day 1. Three outcomes were assessed: persistence of symptoms at day 5, persistence of tympanic membrane changes at day 28, and recurrence of acute symptoms prior to day 28. Persistence of symptoms at day 5 was associated with younger age (35 versus 44 months; p < .001), higher symptom score on day 1 (3.5 versus 2.9; p < .05), and colonization with Streptococcus pneumoniae (61% versus 41%; p < .05). Persistence of tympanic membrane changes at day 28 was associated with younger age (39 versus 45 months; p < .01), higher tympanic membrane score on day 1 (4.1 versus 3.6; p < .01), and nasopharyngeal colonization with S. pneumoniae, especially drug-resistant S. pneumoniae (33% versus 13%; p < .05). Recurrence of acute symptoms prior to day 28 occurred in 14% of the children. Streptococcus pneumoniae was the only pathogen associated with an increased recurrence rate (23%) as compared to the group without pathogens (7%; p < .05). Age, severity of disease at presentation, and nasopharyngeal colonization patterns were proven to be important determinants of outcome in AOM.     

Penicillin resistance is not extrapolable to amoxicillin resistance in Streptococcus pneumoniae isolated from middle ear fluid in children with acute otitis media

OBJECTIVES: We evaluated the in vitro antibacterial activity of amoxicillin against penicillin-susceptible and -nonsusceptible Streptococcus pneumoniae strains isolated from children with acute otitis media (AOM). METHODS: Children more than 3 months of age with AOM who were seen in the Dr Sótero del Rio and Luis Calvo Mackenna Hospitals in Santiago, Chile, between July 1998 and December 2002 were subjected to tympanic puncture for middle ear fluid culture. The penicillin and amoxicillin susceptibilities of the S pneumoniae isolates were determined by epsilometer test (E test). RESULTS: A bacterial pathogen was isolated in 432 of 543 children (80%) as follows: S pneumoniae, 40%; Haemophilus influenzae, 29%; Moraxella catarrhalis, 7%; and Streptococcus pyogenes, 4%. Penicillin-susceptible S pneumoniae strains were less common than amoxicillin-susceptible strains (60% versus 95%; odds ratio [OR], 0.08; 95% confidence interval [CI], 0.04 to 0.18). Both intermediate- and high-resistance strains were more common for penicillin (22% versus 4.5%; OR, 5.6; 95% CI, 2.5 to 12.7) than for amoxicillin (18% versus 0.5%; OR, 41.3; 95% CI, 6.0 to 821). CONCLUSIONS: Penicillin resistance is not extrapolable to amoxicillin among S pneumoniae strains isolated from middle ear fluid of children with AOM. Our results support the recommendation to evaluate the minimal inhibitory concentrations of penicillin-nonsusceptible S pneumoniae for amoxicillin and to continue use of this antimicrobial as a first-line antimicrobial choice for children with AOM.     

Effect of pneumococcal conjugate vaccination on nasopharyngeal carriage in children with early onset of acute otitis media – a randomized controlled trial

Conclusion: Although children vaccinated with heptavalent pneumococcal conjugate vaccine (PCV) had fewer episodes of acute otitis media (AOM), this trial was unable to prove a simultaneous decrease in nasopharyngeal carriage. Objective: Carriage rates of AOM pathogens in the nasopharynx are high among children, and colonization is the first step towards infection. The possible impact of PCV on carriage is therefore of interest, particularly in children with recurrent AOM. The aims of this study were to examine the effect of heptavalent PCV on carriage of AOM pathogens in children at high risk of developing recurrent disease, and to monitor carriage of resistant pathogens in vaccinated and unvaccinated children. Methods: A total of 109 children with an onset of AOM before 6 months of age, 89 of whom developed recurrent disease, were enrolled in a trial. Fifty-two children were vaccinated and all were closely monitored for 3 years. Results: There was no difference statistically between vaccinated children and controls concerning the carriage of any of the major AOM pathogens. There was evidence of within-child clustering for S. pneumoniae (p = 0.002) and H. influenzae (p < 0.001), indicating that children continued to carry either species over time. Resistance rates were generally low and comparable with national levels.     

Failure of antibiotic therapy in acute otitis media

The aim of this retrospective study was to determine the possible causes of failure of antibiotic therapy in children with acute otitis media (AOM). Thirty-nine samples of middle-ear fluid were obtained by myringotomy from 31 children suffering from AOM, unrelieved by antibiotic therapy administered for over 48 hours. The samples were analysed by the usual microbiological techniques, including cultures, tests for beta-lactamase producing strains and the determination of the minimal inhibitory concentration of penicillin for Streptococcus pneumoniae. In 14 samples, no bacterial strains were detected in the cultures of middle-ear fluid; and in two samples the cultures revealed two strains of bacteria. The bacteria most frequently identified were Haemophilus influenzae, found in 11 samples, and Streptococcus pneumoniae, found in seven samples, of which four produced strains with reduced susceptibility to penicillin. The failure of antibiotic therapy in AOM appears to be related to the increased resistance of Haemophilus influenzae and to the reduced susceptibility of Streptococcus pneumoniae to penicillin. Other factors contributing to the failure of antibiotic therapy in AOM may be the viruses or the bacteria that produce multiple pathogens in the middle ear.     

Acute mastoiditis in children: Pseudomonas aeruginosa as a leading pathogen

OBJECTIVE: Acute mastoiditis is a serious bacterial infection of the temporal bone and is the most common complication of otitis media. The goal of this study is to assess the clinical features, pathogens, management, and outcome of acute mastoiditis in children in northern Israel. METHODS: A systematic review of medical records of all children who were admitted with acute mastoiditis from January 1990 through December 2000. RESULTS: Fifty-seven children were included. Median was age: 36 months. In 26 patients (45.6%) mastoiditis complicated the first episode of acute otitis media (AOM). Twenty-five children (44%) received antibiotic treatment prior to admission. Frequent symptoms included mastoid area erythema in 54 children (94.7%), proptosis of the auricle in 52 children (91.2%) and fever in 43 children (75.4%). Middle ear, and subperiostal culture yielded growth of pathogen in 30 children (75%), two cultures yielded more then one pathogen. The most frequent pathogens were: Pseudomonas aeruginosa in 10 children (25%), Streptococcus pneumoniae in eight children (20%), Group A streptococcus in six children (15%). The highest incidence of Streptococcus pneumoniae was found in children who did not suffer from AOM before admission (35 vs. 5%). Fifty-two (91.2%) children were cured with antibiotic treatment alone. Seventeen children underwent computed tomography (CT) of the mastoid. Mastoid bone destruction was demonstrated in six children and subperiostal abscess in eight. Mastoidectomy was performed in five children. CONCLUSIONS: The diagnosis of acute mastoiditis can be made on clinical basis alone requiring CT only when complications are suspected. Half of the children admitted with acute mastoiditis had no previous history of recurrent AOM. In those children S. pneumoniae was the leading pathogen while P. aeruginosa was more prevalent in children with recurrent AOM. Most of the children recovered with medical therapy alone, without surgical intervention.     

Nasopharyngeal pathogens in children with acute otitis media in a low-antibiotic use country

OBJECTIVE: Acute otitis media (AOM) is one of the most common diseases of childhood. Knowledge, of which bacteria are the most common pathogens in AOM and their susceptibilities towards antibiotics, is essential for the reasonable empiric treatment. With rapidly increasing frequencies of antibiotic resistance surveillance of the common etiologic pathogens has become pertinent. The purpose of this paper is to present the bacteriological findings and antibiotic susceptibilities, in cultures from nasopharyngeal swabs, in Danish children with AOM. METHODS: Children aged up to 10 years who had AOM diagnosed in general practice in Denmark were swabbed in nasopharynx, cultures were incubated and susceptibility testing was performed as tablet diffusion and minimal inhibitory concentrations (MICs) were determined by E-test. RESULTS: We included 331 patients, in 257 bacteria were found, which could be classified as commonly ear pathogenic. The most frequent bacteria found was Streptococcus pneumoniae followed by Haemophilus influenzae and Moraxella catarrhalis. Ninety-six percent of the tested S. pneumoniae were susceptible towards penicillin and 99% towards erythromycin. Eighty-nine percent of the H. influenzae were susceptible to ampicillin and all tested M. catarrhalis were susceptible towards erythromycin. In more than 30% of H. influenzae MIC of phenoxymethylpenicillin were above the level that could be achieved in middle ear fluid. CONCLUSION: Antimicrobial resistance is still infrequent in pathogens that might cause AOM in children in Denmark; this is probably due to minimal use of antibiotics as well as the use of phenoxymethylpenicillin as primary drug for treatment of AOM. Phenoxymethylpenicillin and azithromycin are not efficient for treating the majority of infections due to H. influenzae.     

Molecular analysis of pathogens of upper respiratory tract infections in children--a study of nasopharyngeal S. pneumoniae and PBP genes in acute otitis media

We have recently been confronted with refractory upper respiratory infections with an increasing prevalence of penicillin (Pc)-resistant S. pneumoniae. There has been a broad consensus that acute otitis media (AOM) is caused by migration of pathogens from nasopharynx and proliferation in the middle ear space, and thus it is, very important to study the bacterial environment in the nasopharynx as the source of middle ear infections. Eighty pneumococcal isolates from the nasopharynx of children with acute otitis media were evaluated by polymerase chain reaction (PCR) for mutation of Pc-binding protein (PBP) genes. The results showed mutation of all three PBP genes, pbp 1a, pbp 2x, and pbp 2b, in 30% of the isolates, while 74% were found to possess various PBP gene mutations, mostly in one-year-old children. Of the 46 isolates whose minimum inhibitory concentration (MIC) of Pc was < or = 0.06 microgram/mL, 43% were found to possess a pbp 2x mutaion, which affects cefem resistance. We genotyped each pneumococcal isolate from the nasopharynx of children with recurrent AOM by pulsed-field gel electrophoresis (PFGE). In 9 of 11 pairs (82%) of consecutive AOM episodes, the nasopharyngeal isolate in the second episode was different. In addition, discrimination of each isolate based upon the mutation profile of its PBP genes in 8 pairs (72%) of consecutive AOM episodes showed that the isolates were different, and there was little difference between the results of PBP gene mutation and PFGE analysis. These findings suggest that most nasopharyngeal isolates from children with AOM possess PBP mutations and that children with increased numbers of drug-resistant bacteria in their nasopharynx during AOM has been colonized or recolonized by different strains during each episode. We therefore emphasize that clinicians should assess the antibiotic susceptibility of nasopharyngeal isolates from children during each episode. PBP gene mutation analysis of S. pneumoniae is useful not only in providing valuable information on the antibiotic susceptibility of each strain but for assessing changes in causative strains in the sequential episodes of pneumococcal infection.     

Identification of bacterial strain at each episode of recurrent acute otitis media

This study was undertaken to investigate whether each episode of recurrent acute otitis media (rAOM) is caused by the same strain of bacteria or different strains at each episode. Seventy infants less than 3-years of age, having experienced rAOM for a period shorter than 8 weeks, were selected and included in the present study. The total number of AOM episodes experienced by this group was 282. At each subsequent episode of AOM, otorrhea and nasopharyngeal swabs were taken for bacterial culture and determination of the MIC for antibiotics. When S. pneumoniae was identified, its serotype, and its pbp, ermAM, and mefE genes were also investigated to determine the bacterial species and strains. S. pneumoniae was the most frequently cultured bacteria with 26 penicillin-sensitive S. pneumoniae (PSSP), 65 penicillin-insensitive S. pneumoniae (PISP), and 50 penicillin-resistant S. pneumoniae (PRSP). H. influenzae was the next most frequently cultured bacteria of which 65 were sensitive to penicillin, 27 were found to be beta-bactamase-negative-ampicillin-resistant (BLNAR) and 17 were found to be beta-bactamase positive. Bacteria cultured from each pair of two successive episodes of AOM were compared as to the identity of the bacteria during the two episodes. In 150 out of 202 pairs (74%), the cultured pathogen was different. In 22 cases in which either PISP or PRSP was the pathogen detected in two consecutive AOM episodes, 15 cases (68%) were found in which the involved strain differed between the two episodes. This study indicates that the pathogen involved in rAOM is likely to differ at each episode of AOM, not only in cases caused by PSSP, but also in those caused by PRSP.     

C-reactive protein in acute otitis media

Serum C-reactive protein (CRP) levels were studied in 79 children with acute otitis media (AOM), aged from 4 months to 5 years. The CRP was less than 10 mg/l in 27 children, greater than or equal to 20 mg/l in 34, and greater than or equal to 40 mg/l in 17 children, 25 of the 41 attacks caused by S. pneumoniae or H. influenzae showed a CRP of greater than or equal to 20 mg/l and 15 CRP greater than or equal to 40 mg/l, in 38 cases without major otitis pathogens, the respective figures were 9 (p less than 0.01) and 2 (p less than 0.001). Although statistically significant correlations between otitis-related clinical parameters and CRP levels were rare, there was a tendency toward higher CRP values among those with a more severe clinical picture. All five attacks with CRP greater than or equal to 100 mg/l were bilateral, caused by major pathogens, and preceded by a respiratory infection. They also tended to have high fever and a large amount of fluid in myringotomy. However, even in these the general course of AOM and other morbidity was not different from the others.     

Acute otitis media caused by drug-resistant bacteria: correlation with antibiotic treatment

OBJECTIVE: Although acute otitis media (AOM) is the commonest infectious disease of childhood, the emergence of drug-resistant bacteria has dramatically changed its clinical outcome. Here, we report the trend of AOM due to drug-resistant Staphylococcus pneumoniae (DRSP) and beta-lactamase-negative ampicillin-resistant Haemophilus influenzae (BLNAR), and the relation between antibiotics used for the management of AOM and the isolation of bacterial pathogens. MATERIAL AND METHODS: Bacterial isolation and susceptibility tests were performed on specimens from children with AOM. Clinical information, including antibiotic treatment within the previous 30 days, was analyzed. RESULTS: DRSP was detected in 59.3% of Pneumococci isolates and BLNAR in 26.0% of H. influenzae isolates. As expected, the incidence of AOM caused by such drug-resistant bacteria has been increasing year on year, and 32% of cases have been treated with inappropriate antibiotics. In contrast, 32% of cases of AOM caused by DRSP and 50% caused by BLNAR were given antibiotics with high susceptibility to drug-resistant bacteria. CONCLUSION: In order to ensure the most appropriate use of antibiotics, clinicians should consider performing tympanocentesis or myringotomy, with subsequent submission of the middle ear fluid for susceptibility testing. Furthermore, these results suggest that, as well as the selection of antibiotics, the dosage and period of dosing should also be considered in the management of AOM. In addition, other factors, in particular horizontal transmission from other infants in day care or nursery school, may affect the rapid spread of such drug-resistant bacteria.     

Nasopharyngeal colonization of otopathogens in South Indian children with acute otitis media – A case control pilot study

BackgroundAcute otitis media (AOM) is an inflammatory disease of the middle ear causing significant morbidity in early childhood. A pilot study was undertaken to identify the role of various risk factors South Indian children with AOM, especially the role of nasopharyngeal otopathogens.MethodologyA prospective case control pilot study was conducted in children aged below six years, presenting to a single tertiary care from 2018 to 2019. Fifty cases with AOM and 45 age and gender matched controls were recruited. Two nasopharyngeal swabs were collected, one was processed for bacterial culture. The other swab was processed according to the CDC recommended broth enrichment method to identify carriage of S. pneumoniae. Subsequent serotyping was done by Quellung method and conventional sequential multiplex PCR.ResultOtalgia was the major presentation seen in 92% of the children with AOM. None of the clinical and demographic characteristics were found to be statistically significant between the cases and controls. The most common otopathogen was S. pneumoniae (55%) followed by H. influenza (29%). The common S. pneumoniae serotypes encountered were 11A and 19F.Nasopharyngeal colonization with S. pneumoniae [OR 6.57, p < 0.003] and H. influenzae [OR14.18, p < 0.003] were significant risk factors for AOM in children. The risk increased with co-colonization (OR 13.89,p < 0.003).ConclusionThis study strengthens the significant association between nasopharyngeal colonization of otopathogens and AOM as a risk factor that is enhanced by co-colonization.S. pneumoniae was the main otopathogen in this population, serotypes 11A and 19F being the most common.     

Suppurative complications of acute otitis media in the era of antibiotic resistance

OBJECTIVE: To review our experience with suppurative complications of acute otitis media (AOM) in the era of antibiotic resistance, given a perceived increase in the number of such cases in recent years requiring surgical intervention. DESIGN: Retrospective review of pediatric patients presenting with suppurative complications of AOM from January 1993 to June 2000. SETTING: Academic tertiary care children's medical center. PATIENTS: A total of 90 pediatric patients, ranging in age from 3 months to 16 years (mean age, 45 months). RESULTS: A total of 104 suppurative complications of AOM occurred in 90 patients over the 7.5-year study period. The incidence of noncoalescent, coalescent, and total cases of mastoiditis and total number of suppurative complications all increased over the study period, with coalescent outpacing noncoalescent disease during the last 3 years of the study. A trend toward an increasing number of cases requiring surgical intervention was noted during the study period, corresponding to an increasing number of resistant Streptococcus pneumoniae isolates. Ten of 16 S pneumoniae isolates were resistant, primarily collected from younger children ranging in age from 4 to 24 months (mean age, 11.9 months). CONCLUSION: The rising incidence of resistant S pneumoniae corresponded to the increasing number of suppurative complications of AOM during the study period and seemed to contribute to more aggressive infectious processes requiring surgical intervention.     

Pathogens in acute otitis media--impact of intermittent penicillin V prophylaxis on infant nasopharyngeal flora

OBJECTIVE: To investigate whether intermittent short-term courses of penicillin V (PcV) administered as intermittent prophylaxis against acute otitis media (AOM) during upper respiratory tract infections altered the nasopharyngeal bacterial flora and/or its susceptibility to penicillin. METHODS: In a double blind, placebo controlled study 70 children (30 in the PcV group and 40 in the placebo group) were followed for 1 year. At episodes of upper respiratory tract infection the children were given PcV or placebo and then seen by one of the investigators within 3 days. The tympanic membranes were examined by otomicroscopy and a culture from the nasopharynx was obtained. If AOM was found PcV was given (25 mg/kg bw b.i.d) for 5 days. If the child presented normal eardrums or signs of secretory otitis media (SOM) the study treatment was continued for a total of 5 days. All children were also examined bimonthly throughout the study irrespective of episodes of URTI or AOM. RESULTS: No increase in the number of isolates of S. pneumoniae with reduced susceptibility to penicillin (MIC> or =0.125 mg/l) was noted in either group compared with the incidence in the population in Sweden at the time of the study (when ca. 10% of pneumococci had a reduced susceptibility to penicillin). The number of cultures positive for S. pneumoniae were statistically reduced in children during treatment with PcV compared with children receiving placebo, while the number of cultures positive for H. influenzae and M. catarrhalis were unaffected. No increase in the number of cultures positive for beta-lactamase producing H. influenzae was noted (ca. 10%). CONCLUSION: Repetitive short term PcV courses during URTI in infants did not increase the number of cultures positive for S. pneumoniae with reduced susceptibility to penicillin or beta-lactamase producing H. influenzae.     

Vaccination and otitis media

Acute otitis media (AOM) caused by Streptococcus pneumoniae, Haemophilus influenzae or Moraxella catarrhalis may induce specific systemic and/or local immune responses, which may protect from otitis media caused by the same bacteria. However, earlier clinical trials with pneumococcal capsular polysaccharide vaccines have not been successful in preventing AOM. Recently developed pneumococcal polysaccharide-protein conjugates proved immunogenic even in infants, and a heptavalent pneumococcal CRM 197 conjugate vaccine gave a 57% reduction in the number of pneumococcal AOM episodes caused by the vaccine serotypes in infants in Finland. H. influenzae causing AOM is noncapsulated, and like M. catarrhalis, calls for another kind of vaccine development. Suitable vaccine candidates are not yet available but are under development and being tested for immunogenicity and safety. In some trials influenza vaccines have shown protection from AOM during respective viral epidemics. Passive immunoprophylaxis might be an important alternative for immunocompromised children, although this approach has not been successful so far. Mucosal immunization and the advent of DNA and gene technology will open new interesting prospects in the future.     

The potential effect of widespread use of pneumococcal conjugate vaccines on the practice of pediatric otolaryngology: the case of acute otitis media

PURPOSE OF REVIEW: This review provides the otolaryngologist with the evolving understanding of various aspects of pneumococcal conjugate vaccines (PCVs) that are related to their effect on the respiratory tract RECENT FINDINGS: The efficacy of PCVs against invasive pneumococcal disease and pneumonia is well established and is documented in several well-conducted studies. However, the effect of PCVs on otitis media is less obvious and more complex. PCVs clearly reduce diseases caused by vaccine-type (VT) pneumococci, but replacement of VT serotypes by non-VT serotypes in nasopharyngeal carriage of Streptococcus pneumoniae is responsible for the increase in acute otitis media (AOM) caused by non-VT serotypes. Furthermore, an increased rate of AOM caused by Haemophilus influenzae and Moraxella catarrhalis was found. Since most antibiotic-resistance in S. pneumoniae is confined to VT serotypes, vaccine use also reduces antibiotic resistance. The reduction of carriage by PCVs is responsible for the reduction of spread of VT pneumococci (herd immunity). Thus a modification of AOM rather than just a simple reduction is seen with the widespread use of PCV. SUMMARY: Acute otitis media in the era of widespread use of PCV is modified. A disease with reduced VT serotypes, reduced antibiotic resistance, and a lower rate of sequelae is to be expected. However, replacement with potential virulent organisms and development of antibiotic resistance in non-VT pneumococci is a possibility that needs careful monitoring.