Cases Of Pneumococcal Meningitis Research Articles

Serotyping Pneumococcal Meningitis Cases in the African Meningitis Belt by Use of Multiplex PCR with Cerebrospinal Fluid

We reformulated a multiplex PCR algorithm for serotyping of pneumococcal meningitis directly on cerebrospinal fluid (CSF). Compared to established methods on isolates, CSF-based PCR had at least 80% sensitivity and 100% specificity. In regional meningitis surveillance, CSF-based PCR increased the serotype information yield from 40% of cases (isolate testing) to 90%.

Insidious presentation of pediatric pneumococcal meningitis: alive and well in the post vaccine era

Routine childhood vaccination against H influenza type b and S pneumoniae has dramatically reduced the incidence of pediatric bacterial meningitis. Because of the decreased incidence of this disease, individual emergency physicians will have limited opportunity to experience the diverse clinical manifestations of this disease. Insidious presentations of this diagnosis still occur but would now be considered rare events for emergency physicians. It is imperative to recognize that young infants with bacterial meningitis can present without fever or irritability and manifest signs and symptoms consistent with many other diagnoses. Careful study of prior cases and sustained clinical vigilance are required to capture these cases. In this report, we present 3 cases of pneumococcal meningitis in young infants presenting with indolent features. None of the patients presented with a chief complaint of irritability, poor feeding, or altered mental status, and no patient had high fever, difficulty consoling, or cirulatory compromise.

Méningite à pneumocoque de sérotype 19F chez un enfant immunocompétent ayant reçu 3 injections du vaccin pneumococcique conjugué heptavalent Prevenar®

Seven cases of pneumococcal meningitis caused by serotypes covered by the available vaccine occurred in France in vaccinated children, 4 of which were caused by serotype 19F. A 3-year-old child, who had received 3 doses of the 7-valent pneumococcal conjugate vaccine Prevenar but not the 4th injection, presented with bacterial meningitis after acute media otitis. The identified bacterium was a 19F serotype of Streptococcus pneumoniae. This vaccine failure was characterized by an immune memory installation defect and underscores the necessity of the booster dose of vaccine during the 2nd year of life to acquire rates of protective and lasting antibodies. Serotype 19F of S. pneumoniae is particular since, despite good immunogenecity, it induces antibodies with weak avidity. We describe a case of pneumococcal meningitis caused by 19F serotype S. pneumoniae, which is included in the vaccine, in an immunocompetent child. Such events should be inventoried. They can reveal rates of antibodies that are very weak defenders, in spite of the vaccination, reflecting the absence of implementation of immunizing memory. Furthermore, an underlying immune deficit must be ruled out.

Neurodevelopmental Sequelae in Pneumococcal Meningitis Cases in Bangladesh: A Comprehensive Follow‐up Study

Evaluation of the long-term impact of pneumococcal meningitis on surviving children and their families is critical to fully comprehending the burden of pneumococcal disease and to facilitating an evidence-based decision for the introduction of pneumococcal vaccine. This study was an investigation of the short- and long-term impacts of pneumococcal meningitis among Bangladeshi children. Case patients with pneumococcal meningitis who were hospitalized between January 2006 and March 2007 were subjected to short-term follow-up within 30-40 days of discharge. Case patients discharged prior to January 2005 were selected for long-term follow-up at 6-24 months after the date of discharge. Both cohorts were enrolled from Dhaka Shishu Hospital, a pediatric hospital in Bangladesh. Healthy children matched for age, sex, socioeconomic status, and area of residence were recruited from the community as control subjects. During follow-up visits, case patients and control subjects were assessed for their physical and neurodevelopmental status by use of a standardized protocol. The impact of pneumococcal meningitis on siblings and the family as a whole was assessed by means of qualitative interviews. Neurodevelopmental assessments of the short-term follow-up cohort (n=51) revealed hearing, vision, mental, and psychomotor deficits in 33%, 8%, 41%, and 49% of the case patients, respectively. These deficits were 18%, 4%, 41%, and 35% in the long-term follow-up cohort (n=51), respectively. Such deficits were seen in only 2% of the control subjects, none of whom had vision or hearing deficits. In addition to the risk of death, pneumococcal meningitis in children causes severe disabilities among survivors, as well as disruption of the life of other siblings and family members. This study demonstrated that high rates of sequelae are associated with pneumococcal meningitis. Neurodevelopmental assessment during follow-up of patients with meningitis is critical to our understanding of the burden of the adverse consequences of pneumococcal disease. These data, along with the fact of poor access to health care, provide a compelling argument in favor of the introduction of pneumococcal vaccine, specifically in a setting where access to health care is poor and disabled children remain incapacitated because of a lack of resources and facilities.

Enhanced Diagnosis of Pneumococcal Meningitis with Use of the Binax NOW Immunochromatographic Test ofStreptococcus pneumoniaeAntigen: A Multisite Study

Accurate etiological diagnosis of meningitis in developing countries is needed, to improve clinical care and to optimize disease-prevention strategies. Cerebrospinal fluid (CSF) culture and latex agglutination testing are currently the standard diagnostic methods but lack sensitivity. We prospectively assessed the utility of an immunochromatographic test (ICT) of pneumococcal antigen (NOW Streptococcus pneumoniae Antigen Test; Binax), compared with culture, in 5 countries that are conducting bacterial meningitis surveillance in Africa and Asia. Most CSF samples were collected from patients aged 1-59 months. A total of 1173 CSF samples from suspected meningitis cases were included. The ICT results were positive for 68 (99%) of the 69 culture-confirmed pneumococcal meningitis cases and negative for 124 (99%) of 125 culture-confirmed bacterial meningitis cases caused by other pathogens. By use of culture and latex agglutination testing alone, pneumococci were detected in samples from 7.4% of patients in Asia and 15.6% in Africa. The ICT increased pneumococcal detection, resulting in similar identification rates across sites, ranging from 16.2% in Nigeria to 20% in Bangladesh. ICT detection in specimens from culture-negative cases varied according to region (8.5% in Africa vs. 18.8% in Asia; P< .001), prior antibiotic use (24.2% with prior antibiotic use vs. 12.2% without; P< .001), and WBC count (9.0% for WBC count of 10-99 cells/mL, 22.1% for 100-999 cells/mL, and 25.4% for >or=1000 cells/mL; P< .001 by test for trend). The ICT provided substantial benefit over the latex agglutination test and culture at Asian sites but not at African sites. With the addition of the ICT, the proportion of meningitis cases attributable to pneumococci was determined to be similar in Asia and Africa. These results suggest that previous studies have underestimated the proportion of pediatric bacterial meningitis cases caused by pneumococci.

The cost-burden of paediatric pneumococcal disease in Sweden and the potential cost-effectiveness of prevention using 7-valent pneumococcal vaccine

Aims A cost-effectiveness model was used to estimate the change in disease burden that might be expected if PCV7 was included as part of the routine 3-dose vaccination schedule in Sweden. Methods An economic model was populated with data from the main clinical PCV7 efficacy trials, demographic data from government sources, surveillance and epidemiologic data from the US and Nordic region, and average treatment costs, considering the impact of disease on the whole national population. Results The model estimated that PCV7 would prevent 18,856 cases of AOM, 684 of pneumonia, 86 of pneumococcal bacteraemia and 21 cases of pneumococcal meningitis in children <10 years, further 221 cases of IPD would be avoided in older children and adults and 397 cases of pneumonia in adults aged 18–39 years. Annually, 4 childhood (<10 years) deaths and 39 deaths in older children and adults would be prevented, resulting in an annual saving of 632 life years. The reduction of cost for the society was estimated to 27.9 (−205, +160) million SEK. The sensitivity analysis showed that it was most sensitive to the efficacy of the vaccine against AOM, the cost of managing infections and the incidence of all disease. Conclusion This model demonstrates that implementing a universal vaccine programme in Sweden with PCV7 would be cost-effective with an estimated net reduction of costs for the society.

Méningites à pneumocoque de l'enfant en France : 832 cas de 2001 à 2007

Pneumococcal meningitis represents one major cause of morbidity and mortality in children in France. The GPIP/ACTIV (Groupe de Pathologie Infectieuse Pédiatrique and Association Clinique et Thérapeutique Infantile du Val de Marne) set up an active surveillance network to analyze the clinical and biological features of pneumococcal meningitis and the impact of 7-valent pneumococcal conjugate vaccine (PCV7). From 2001 to 2007, 252 French pediatric wards working with 168 microbiology laboratories enrolled all children (0-18 years old) with bacterial meningitis. Risk factors, signs and symptoms, vaccination status, cerebrospinal fluid analysis, treatments and case fatality rate were recorded. Within the 7 years study period, 832 pneumococcal meningitis were reported among 2951 bacterial meningitis. In 2001 as in 2007, excluding the neonatal period, pneumococal meningitis represented nearly 1/3 of bacterial meningitis without significant decline in the number of reported cases (less than 30% for children under 2 years old). The peak of incidence was at 5 months of age and 61.7% of cases occured in children 2 to 24 months old. PCV7 vaccinated patients represented 154 cases from 2003 to 2007. In the vaccinated population, serotypes were identified in 136 cases. Few vaccine serotypes (VT) were identified (n=18). The most important was serotype 19F (n=8) followed by 6B (n=4) and 14 (n=3). Three vaccine failures (case occurring after complete vaccination) were observed (serotypes 6B, 4 and 19F). Remaining cases (n=118) were mainly due to non vaccine serotypes (NVT): serotypes 19A, 15B/C and 7F. In 2007, the serotype 19A, more often intermediary strains to cytoxin, represented about 20% of cases. Among non vaccinated children, VT decreased between 2001 and 2007 (59/92 in 2001 vs 15/39 in 2007). Case fatality rate was stable around 11.4%. In France, probably because of the insufficient vaccination coverage and the slow implementation of the PCV7, the expected decline in the number of cases of pneumococcal meningitis has not been observed. The impact of PCV7 appeared clearly since only few cases of VT pneumococcal meningitis were reported in vaccinated children.

Epidemiology of invasive pneumococcal disease in the Arabian Peninsula and Egypt

Invasive pneumococcal disease (IPD) causes considerable morbidity and mortality among children worldwide. This review describes the burden of disease and pneumococcal serotypes/serogroups causing disease in children in the Arabian Peninsula and Egypt identified from a literature search from 1990 to 2007. The incidence of IPD in children aged ≤5 years ranged from 3.4 to 53.5 per 100000. Bacteraemia cases were responsible for 61–100% (children <2 years) of total IPD. Pneumococcal meningitis cases ranged from 3% to 25% (<2 years) and from 7% to 30% (≤5 years). The most common IPD serotypes/serogroups were 14, 23F, 6B, 19F and 6A (≤5 years). Circulating serotypes/serogroups causing IPD potentially covered by the 7-valent pneumococcal conjugate vaccine (PCV-7) ranged from 49% to 83% (<2 years) and from 61% to 69% (≤5 years). Penicillin resistance among invasive isolates ranged from 0% to 78%. Case fatality and morbidity rates for pneumococcal meningitis were 0–22% and 10–62%, respectively. Incidence and morbidity data for meningitis and bacteraemia demonstrate a substantial vaccine-preventable burden of IPD in young children. Standardisation of definitions and development of improved regional surveillance/reporting would enable the region to measure better the impact of prevention strategies for IPD, such as infant-based immunisation programmes.

Epidemiologic and Microbiologic Characteristics of Recurrent Bacterial and Fungal Meningitis in The Netherlands, 1988–2005

Patients may experience multiple episodes of bacterial meningitis. Information from large studies of recurrent meningitis is limited. We evaluated the incidence of recurrent bacterial meningitis and the distribution of causative organisms in The Netherlands. Data for patients with bacterial meningitis were prospectively collected nationwide for the period 1988-2005. Recurrent meningitis was defined as an episode of meningitis that either occurred >or=28 days after a previous episode or occurred <28 days after a previous episode but was caused by a different pathogen or different subtype of the same pathogen. Of 18,915 patients, 202 (predominantly male) patients had recurrent bacterial meningitis (P< .01). Prevailing causative organisms were Streptococcus pneumoniae (40% of cases), Neisseria meningitidis (22%), and non-type b Haemophilus influenzae (9%). Pneumococci serotypes included in the heptavalent vaccine caused only 36% of cases of recurrent pneumococcal meningitis. The proportion of episodes caused by meningococcus serogroups W135, Y, and Z was higher among patients with recurrent meningitis than among those with nonrecurrent meningitis (odds ratio, 12.8), and the proportion caused by nontypeable and type f H. influenzae was also higher among patients with recurrent meningitis (odds ratio, 3.8 and 5.6, respectively). In The Netherlands, the prevalence of recurrent bacterial and fungal meningitis is low. The distribution of causative microorganisms differs between cases of recurrent meningitis and cases of nonrecurrent meningitis; this could be associated with vaccination.

Serious Neurologic Sequelae in Cases of Meningitis Arising From Infection by Conjugate Vaccine-Related and Nonvaccine-Related Serogroups of Streptococcus pneumoniae

Introduction of the heptavalent conjugate vaccine for Streptococcus pneumoniae (PCV7) has led to a dramatic decline in meningitis by PCV7 serotypes, raising the possibility of similar trends by PCV7-related serogroups through cross-protection. A present concern, however, is of serotype replacement by pneumococci not related to PCV7 serogroups. If this occurs, there are currently few data to predict whether clinical outcomes will change substantially. To address these questions, we analyzed medical records of 86 cases of pneumococcal meningitis treated at Nationwide Children's Hospital (1993-2004). Adverse neurologic sequelae and death were compared between cases with cerebrospinal fluid isolates characterized as vaccine-related serogroups-serotypes belonging to PCV7 or related to PCV7 serogroups, and those designated nonvaccine serogroups-serotypes neither belonging to PCV7 nor related to PCV7 serogroups. Serotype 19A, because of recent reports of increased incidence, was subanalyzed separately. Thirty-six of 86 (42%) subjects had serious complications, including 6 who died. All 6 deaths occurred in patients with vaccine-related serogroups. Deafness was the most common complication, occurring in 26 (32.5%) survivors. There was no difference in the frequency of total complications between PCV7-related and non-PCV7 groups: 5 of 12 (42%) for non-PCV7 serogroups versus 31 of 74 (42%) for PCV-related serogroups (OR: 1.0; 95% CI: 0.2-4.0). Serious outcomes occurred in 3 of 4 cases due to serogroup 19A. Non-PCV7 serogroups increased slightly at the end of the study period. In children with pneumococcal meningitis, infections with non-PCV7 serogroups seem less likely to result in death. Among survivors, there is preliminary evidence of parity in neurologic sequelae between PCV7 and non-PCV7 serogroups.

Otogenic Pneumococcal Meningitis with Pneumocephalus

Streptococcus pneumoniae accounts for approximately 50% of bacterial meningitis cases in the United States annually. Since the advent of antibiotics, pneumococcal meningitis as a complication of a primary otogenic focus has been rare in the United States. The widespread use of immunosuppressants and increasing bacterial resistance to commonly prescribed antibiotics may contribute to a higher incidence of complications of otitis media in the future, similar to that of the pre-antibiotic era. We report a case of otogenic pneumococcal meningitis with pneumocephalus in an adult male on chronic immunosuppressant therapy. A 33-year-old man with Crohn's disease and azathioprine use presented to our Emergency Department with progressive headache while taking antibiotics for otitis media. Initial computed tomography scan of the brain revealed pneumocephaly, and cerebrospinal fluid analysis and culture diagnosed pneumococcal meningitis. The patient continued to have fevers while receiving intravenous antibiotics and underwent bilateral myringotomies; his clinical course subsequently improved significantly. Meningitis is a rare complication of Streptococcus pneumoniae infections since the advent of antibiotics; however, it may become more frequent with increasing antibiotic resistance and a growing population of immunocompromised patients. Additionally, pneumocephalus in the setting of meningitis and otitis media should raise the suspicion for mastoiditis (even without overt clinical findings) and early consultation with an otolaryngologist is warranted.

Changing Epidemiology of Pneumococcal Meningitis after the Introduction of Pneumococcal Conjugate Vaccine in the United States

Although hospitalizations due to invasive pneumococcal disease decreased after routine vaccination of young children with a 7-valent pneumococcal conjugate vaccine (PCV7) began in 2000, information on the trends in pneumococcal meningitis is limited. We estimated national trends in rates of hospitalization for pneumococcal meningitis, using data from the Nationwide Inpatient Sample, 1994-2004. Pneumococcal meningitis cases and deaths were identified on the basis of the International Classification of Diseases, Ninth Edition, Clinical Modification coded primary discharge diagnosis, and rates were calculated using US Census data as denominators. The year 2000 was considered to be a transition year, and the average annualized rate after PCV7 introduction (2001-2004) was compared with that during the baseline years (1994-1999). During 1994-2004, there were 21,396 hospitalizations and 2684 deaths (12.5%) due to pneumococcal meningitis in the United States. In children aged < 2 years, the average annualized rates of pneumococcal meningitis hospitalizations per 100,000 population decreased from 7.7 in 1994-1999 to 2.6 in 2001-2004 (change, -66.0%; 95% confidence interval [CI], -73.5% to -56.3%). Among children aged 2-4 years, the hospitalization rate decreased from 0.9 to 0.5 per 100,000 (change, -51.5%; 95% CI, -66.9% to -28.9%). Average rates also decreased by 33.0% (95% CI, -43.4% to -20.9%) among adults aged > or = 65 years. After PCV7 introduction (2001-2004), an estimated 1822 and 573 pneumococcal meningitis hospitalizations were prevented in persons aged < 5 years and > or = 65 years, respectively. Overall, an estimated 3330 pneumococcal meningitis hospitalizations and 394 deaths were prevented in persons of all ages during 2001-2004 in the United States. After implementation of routine childhood vaccination with PCV7, hospitalizations for pneumococcal meningitis decreased significantly for both children and adults. Most pneumococcal meningitis cases now occur among adults.

Cost-effectiveness analysis of a universal vaccination programme with the 7-valent pneumococcal conjugate vaccine (PCV-7) in Sweden

The 7-valent pneumococcal conjugate vaccine (PCV-7) has proved to be highly effective against invasive pneumococcal disease and has also provided some protection against all-cause pneumonia and acute otitis media. The objective of this study was to evaluate the projected health benefits, costs and cost-effectiveness of vaccination with the 7-valent conjugated pneumococcal vaccine compared with no vaccination, in all infants in Sweden, taking herd immunity into account. A Markov model was used and a hypothetical birth cohort was simulated for a lifelong perspective. The results show that vaccination of 1 cohort could potentially prevent 9 cases of pneumococcal meningitis, 22 cases of pneumococcal septicaemia, 509 cases of hospitalized pneumonia, 7812 cases of acute otitis media, and 2.7 fatalities, among children 0-4 y of age and 6 episodes of pneumococcal meningitis and 167 cases of pneumococcal septicaemia among adults. The incremental cost per QALY and LY gained was estimated to Euro 29,200 and Euro 51,400, respectively. When herd immunity was accounted for, the cost per QALYand LY gained was estimated to Euro 5500 and Euro 6600, respectively. Thus, the health benefits of a national vaccination programmeme can be achieved within a 'moderate' or 'low' cost per QALY gained.

Pneumococcal meningitis in the era of pneumococcal conjugate vaccine implementation

The French Pediatric Infectious Diseases Group set up an active surveillance network to analyze the clinical and biological features of pneumococcal meningitis and the impact of the seven-valent pneumococcal conjugate vaccine (PCV7). From 2001 to 2005, 234 pediatric wards working with 166 microbiology laboratories enrolled all children with pneumococcal meningitis. Risk factors, signs and symptoms, vaccination status, cerebrospinal fluid analysis, treatments and case fatality rates were recorded. One hundred and sixty-nine centers (169/234) reported 616 cases, median age was 0.9 years and 67.2% of children were < or =2 years old. Underlying conditions were present in 13.1% of cases. The proportion of penicillin non-susceptible strains was 48.7%. Vancomycin plus a third-generation cephalosporin was prescribed in 92.7% of cases, and steroids were given before antibiotic treatment in 16.5% of cases. The case fatality rate was 10.8% overall and was not related to age, antibiotic susceptibility or steroid use. In children 2 to 24 months old compared to the prevaccinal period (2001-2002) a decrease of 28.4% of the number of cases was observed in 2005 (P < 0.05). Among children 2 to 24 months old, the proportion of serotypes covered by the PCV7 fell from 39/57 (68.4%) in 2001-2002 to 19/45 (42.2%) in 2005, while the proportion of non-vaccine serotypes and related serotypes increased respectively from 9/57 (15.8%) and 9/57 (15.8%) in 2001-2002 to 14/45 (31.1%) and 12/45 (26.7%) in 2005. Among 52 cases of pneumococcal meningitis that have occurred in vaccinated children (> or =1 dose) with PCV7, 7 were due by vaccine serotypes. This study provides data on underlying conditions, penicillin susceptibility, serotype evolution according to vaccination status and risk factors for mortality for pneumococcal meningitis in children from 2001-2005 in France.

Pneumococcal Meningitis during Pregnancy: A Case Report and Review of Literature

Background. Bacterial meningitis is a medical emergency for which prompt diagnosis and treatment are imperative to reducing the rate of death and long-term neurologic compromise. Few cases of meningitis have been reported during pregnancy, many of which had devastating outcomes for mother, neonate, or both. Case. A 38-year-old multigravida at 35 weeks of gestation presented with mental status changes, fever, and preterm contractions. Lumbar puncture revealed gram positive cocci consistent with S. pneumoniae. Patient was intubated and admitted to ICU where she was given antibiotics and adjunctive therapy with dexamethasone. Continuous fetal monitoring was utilized throughout her course of her hospitalization. Patient was discharged home after ten days in the hospital and had an uncomplicated vaginal birth after caesarean section (VBAC) at 38 weeks. Both she and the infant are doing well with no permanent neurologic sequelae. Conclusion. A review of literature indicates only isolated cases of pneumococcal meningitis being described during pregnancy. An extended period of time between onset of maternal illness and delivery appears to reduce the risk of neonatal transmission and improve both maternal and fetal outcomes.

Mortalité par méningites à pneumocoque chez l'enfant. Facteurs pronostiques à propos d'une série de 73 observations

Objective Despite advances in antibiotic therapy strategies and pediatric intensive care, prognosis of Streptococcus pneumoniae meningitis remains very poor. To determine the factors associated with hospital mortality of children with pneumococcal meningitis. Methods We conducted a retrospective study of 73 cases of childhood pneumococcal meningitis admitted in 4 teaching hospitals in the center of Tunisia during a 8-year period (1995–2002). Results Hospital mortality was 13.7% (10 of 71 patients), and neurologic sequela were observed in 34.5% of survivors. Based on univariable analysis, five variables were associated with the outcome: Pediatric Risk of Mortality score ( p < 0.001), coma ( p = 0.0009), use of mechanical ventilation ( p = 0.0001), convulsions ( p = 0.0449), and shock ( p = 0.0085). In multivariable analysis, only 2 factors were independently associated with inhospital mortality: Pediatric Risk of Mortality score and the use of mechanical ventilation. 11.8% of pneumococcal isolates were intermediate and resistant to penicillin. Non-susceptible pneumococcus strains to penicillin and the use of steroids were not associated significantly with the mortality rate. Conclusions Pneumococcal meningitis remains a devastating childhood disease. Two variables were independently associated with the in-hospital death in our series (high Pediatric Risk of Mortality score, and the use of mechanical ventilation). According to these data we may recommend the inclusion of vaccination against streptoccoccus pneumonia in the children immunization program in Tunisia.

Pneumococcal Meningitis Threshold Model

A minimal threshold of Streptococcus pneumoniae is required to induce meningitis in healthy animals for intraperitoneal (hematogenous), middle ear, and inner ear inoculations, and this threshold may be altered via recent inner ear surgery. There has been an increase in the number of reported cases of cochlear implant-related pneumococcal meningitis since 2002. The pathogenesis of pneumococcal meningitis is complex and not completely understood. The bacteria can reach the central nervous system (CNS) from the upper respiratory tract mucosa via either hematogenous route or via the inner ear. The establishment of a threshold model for all potential routes of infection to the CNS in animals without cochlear implantation is an important first step to help us understand the pathogenesis of the disease in animals with cochlear implantation. Fifty-four otologically normal adult Hooded Wistar rats (27 receiving cochleostomy and 27 controls) were inoculated with different amounts of bacterial counts via three different routes (intraperitoneal, middle ear, and inner ear). Rats were monitored during 5 days for signs of meningitis. Blood, cerebrospinal fluid, and middle ear swabs were taken for bacterial culture, and brains and cochleae were examined for signs of infection. The threshold of bacterial counts required to induce meningitis is lowest in rats receiving direct inner ear inoculation compared with both intraperitoneal and middle ear inoculation. There is no change in threshold between the group of rats with cochleostomy and the control (Fisher's exact test, p < 0.05). A minimal threshold of bacteria is required to induce meningitis in healthy animals and is different for three different routes of infection (intraperitoneal, middle ear, and inner ear). Cochleostomy performed 4 weeks before the inoculation did not reduce the threshold of bacteria required for meningitis in all three infectious routes. This threshold model will also serve as a valuable tool, assisting clinicians to quantitatively analyze if the presence of a cochlear implant or other CNS prostheses alter the risk of meningitis.

Pneumococcal Meningitis Epidemics in Africa

Outbreaks of meningococcal meningitis are not uncommon. In industrialized countries, epidemics increase and decrease in severity slowly over a number of years and rarely achieve very high incidence rates of disease. In sub-Saharan Africa, the situation is different. Within the African meningitis belt, which extends across the Sahel and sub-Sahel from Ethiopia in the east to The Gambia in the west, major epidemics of meningococcal disease occur every few years [1]. These epidemics show a characteristic association with season. They almost always start early in the dry season, build to a peak at the hottest and driest time of the year, and then abate rapidly with the onset of the rains [2]. The reason for this remarkable seasonality is unknown, but climatic factors—in particular, a low absolute humidity—almost certainly play a central role [3]. In contrast, pneumococci are not usually considered to be a cause of meningitis epidemics. Outbreaks of invasive pneumococcal disease are reported from time to time in industrialized countries among people living in poor social circumstances, such as centers for the indigent, prisons, and military camps, but these outbreaks usually involve only a handful of cases. Thus, the recent reports of major outbreaks of pneumococcal meningitis in countries located in the African meningitis belt that have many of the epidemiological features of classic meningococcal epidemics are of concern [4, 5]. Surveillance of cases of meningitis and longitudinal surveys of nasopharyngeal carriage of meningococci have been underway in the Kassena-Nankana region of northern Ghana since 1998. Carriage studies have shown fluctuations in the prevalence of meningococci of different serogroups and sequence types over time, including a wave of infections caused by meningococci belonging to serogroup X [6, 7]. Surveillance of admissions to the district hospital showed a marked increase in the number of cases of pneumococcal meningitis in 2002 and 2003; 1100 patients were seen during this 2-year period [4]. All age groups were affected, and the case fatality rate of 44% was high. A strong association with season was observed; an increase in the number of cases of pneumococcal meningitis occurred approximately a month before there was an increase in the number of cases of meningococcal meningitis. Examination of the pneumococci responsible for this outbreak showed that 76% of isolates belonged to serogroup 1. On multilocus sequence typing, most isolates belonged to a single sequence type, ST217, and its 2 single-locus variants ST303 and ST612. Recently, the number of cases of meningitis caused by pneumococci of this serotype has decreased in the study area (G. Plutschke, personal communication), which suggests a natural cycle of penetration of a susceptible population by a new strain of bacteria and its subsequent elimination as a result of naturally acquired immunity; no pneumococcal vaccination has been undertaken. Unusual events have also been taking

Carriage of Streptococcus pneumoniae in healthy Norwegian children attending day-care centres

An observational study to examine Streptococcus pneumoniae carriage in Norwegian children was initiated after two cases of pneumococcal meningitis, caused by the England(14)-9 clone, occurred in one day-care centre in Oslo. All children recruited from the day-care centre where the cases occurred were vaccinated with a seven-valent pneumococcal conjugate vaccine; the other participants who attended three other day-care centres nearby were not. The children were followed for 9 months, and three samplings took place. At the first visit, 45.7% of the children were colonised by pneumococci in the nasopharynx. The children harboured a variety of serotypes, with serotypes 6A, 23F, 6B and 19F being the most frequent. The numbers of children carrying vaccine serotypes decreased in both the vaccinated and the non-vaccinated groups. Thus, no significant effect of vaccine on carriage was detected in this relatively small study.

Response to ‘Benefits of glucocorticoids in the treatment of bacterial meningitis in children: End of the controversy?’

Response to ‘Benefits of glucocorticoids in the treatment of bacterial meningitis in children: End of the controversy?’