Pyogenic meningitis in hospitalized children in Kelantan, Malaysia

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.

Invasive meningococcal disease in Malaysia, Philippines, Thailand, and Vietnam: An Asia-Pacific expert group perspective on current epidemiology and vaccination policies

Invasive meningococcal disease (IMD) imposes a significant burden on the global community due to its high case fatality rate (4-20%) and the risk of long-term sequelae for one in five survivors. An expert group meeting was held to discuss the epidemiology of IMD and immunization policies in Malaysia, Philippines, Thailand, and Vietnam. Most of these countries do not include meningococcal immunization in their routine vaccination programs, except for high-risk groups such as immunocompromised people and pilgrims. It is difficult to estimate the epidemiology of IMD in the highly diverse Asia-Pacific region, but available evidence indicate serogroup B is increasingly dominant. Disease surveillance systems differ by country. IMD is not a notifiable disease in some of them. Without an adequate surveillance system in the region, the risk and the burden of IMD might well be underestimated. With the availability of new combined meningococcal vaccines and the World Health Organization roadmap to defeat bacterial meningitis by 2030, a better understanding of the epidemiology of IMD in the Asia-Pacific region is needed.

Vaccine preventable meningitis in Malaysia: epidemiology and management

Worldwide bacterial meningitis accounts for more than one million cases and 135,000 deaths annually. Profound, lasting neurological complications occur in 9-25% of cases. This review confirms the greatest risk from bacterial meningitis is in early life in Malaysia. Much of the disease burden can be avoided by immunization, particularly against Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae. Despite inclusion of the Hib vaccine in the National Immunisation Programme and the licensure of pneumococcal vaccines, these two species are the main contributors to bacterial meningitis in Malaysia, with Neisseria meningitidis and Mycobacterium tuberculosis, causing a smaller proportion of disease. The high Hib prevalence may partly be due to dated, small-scale studies limiting the understanding of the current epidemiological situation. This highlights the need for larger, better quality surveillance from Malaysia to evaluate the success of Hib immunization and to help guide immunization policy for vaccines against S. pneumoniae and N. meningitidis.

Meningococcal disease in Asia: an under-recognized public health burden

A literature search traced existing information on meningococcal disease in Asia. Reviewed data describing the epidemiology of meningococcal disease in Asia are incomplete, due in part to absence of surveillance in many countries, poor bacterial detection methods and social and healthcare barriers to disease reporting. This suggests that meningococcal disease in some Asian countries may be under-recognized, with a need to introduce/improve existing surveillance and case identification systems. Nevertheless, in some developing Asian countries, the disease burden may be significant. Serogroup A meningococcal epidemics are responsible for high morbidity and mortality in some countries and continue to be an ongoing threat, particularly in developing countries. There is an increasing role played by serogroups C, Y, and W-135 in invasive disease, indicating evolving meningococcal disease epidemiology in some countries. Multivalent meningococcal conjugate vaccines offer new opportunities in the region for reducing the meningococcal disease burden.

Capsular serotype and antibiotic resistance of Streptococcus pneumoniae isolates in Malaysia

Background

Streptococcus pneumoniae is a major causative agent of severe infections, including sepsis, pneumonia, meningitis, and otitis media, that has since become a major public health concern. In this study, the serotypes distribution of pneumococcal isolates was investigated to predict the efficacy of the 7-valent pneumococcal conjugate vaccine (PCV7) among the Malaysian populations.

Methodology/Principal Findings

A total of 151 clinical isolates were serotyped using multiplex PCR assays. Out of them, there were 21.2% penicillin-resistant, 29.1% penicillin-intermediate, and 49.7% penicillin-susceptible S.pneumoniae strains. Serotypes detected among the Malaysian isolates were 1, 3, 10A, 11A/11D, 12F/12A, 14, 15A, 15B/15C, 16F, 18C/18B/18A/18F, 19A, 19F, 23F, 35B, 35F/47F, 6A/6B, 7C/7B/40, 7F/7A, 9V/9A, and 34. Serotype 19F and 23F were the two most prevalent serotypes detected. Serotypes are highly associated with invasiveness of isolates (p = 0.001) and penicillin susceptibility (p<0.001). Serotype 19F was observed to have increased resistance against penicillin while serotype 19A has high invasive tendency. Age of patients was an important factor underlying the pneumococcal serotypes (p = 0.03) and clinical sites of infections (p<0.001). High prevalence of pneumococcal isolates were detected among children <5 years old at nasopharyngeal sites while elderly adults ≥60 years old were at increased risk for pneumococcal bacteremia.

Conclusion/Significance

Current study revealed that a number of serotypes, especially those associated with high penicillin resistance, have been formulated in the PCV7. Therefore, the protections expected from the routine use of PCV7 would be encouraging for the Malaysian. However, it is not possible to predict serotypes that might become predominant in the future and hence continued surveillance of circulating serotypes will be needed.

Nontraumatic coma in a tertiary pediatric emergency department in egypt: etiology and outcome

Nontraumatic coma in childhood is an important pediatric emergency with a wide range of primary etiologies. This prospective descriptive study of 100 consecutive pediatric nontraumatic coma cases was done to identify etiology, clinical profile, and predictive outcome in a pediatric emergency department at a tertiary care university hospital. Most frequent etiologies were metabolic (33%), central nervous system infections (28%), and intracranial hemorrhage (13%). In the emergency department, 50% of those patients died. Hypothermia, hypotension, flaccidity, and poor Glasgow coma scale at admission correlated significantly with mortality. After 48 hours of admission, poor pulse volume, poor Glasgow coma scale, abnormal respiratory pattern/apnea, and seizures correlated significantly with mortality. On logistic regression, poor Glasgow coma scale at admission, abnormal respiratory pattern, and seizures after 48 hours of admission were independent significant predictors of mortality. Metabolic causes are the most common etiology in pediatrics nontraumatic coma. Simple clinical signs were good predictors of outcome.

Overview of the disease burden of invasive pneumococcal disease in Asia

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

Epidemiology of invasive Haemophilus influenzae type b disease in Singapore children, 1994–2003

Invasive Haemophilus influenzae type b (Hib) diseases are major causes of childhood morbidity and mortality. For the period from 1994 to 2003, we retrospectively identified 53 children with invasive Hib disease including 31 with meningitis, 14 with pneumonia, 2 with septic arthritis, 2 with epiglottitis, 1 with neutropenic sepsis, and 3 who were bacteraemic without a focus. Two children died and 22 had serious sequelae; significantly, survivors with sequelae had presented with meningitis (P-value<0.001) or sepsis (P-value=0.001). During the 11-year period, the annual incidence of invasive Hib disease was estimated to be 4.4/100,000 children <5 years old. With rising affluence, decreasing costs of vaccines, and increased costs in caring for survivors, universal infant immunization with Hib vaccine may need to be reconsidered in Singapore.

Clinical predictors of bacterial meningitis in infants and young children in The Gambia

BACKGROUND

Bacterial meningitis is an important cause of childhood morbidity and mortality world-wide. In the developing world, where the burden of acute meningitis and its long-term sequelae are especially high, staff with limited training at primary health care facilities must be able to recognize the symptoms and signs of meningitis, so that suspected cases can be referred urgently to hospitals.

METHODS

Children who presented with possible invasive bacterial infection to health facilities in The Gambia, West Africa, between 1993 and 1995 were investigated in a standardized manner and clinical findings were documented. Bacterial meningitis was defined as the growth of bacteria from the cerebrospinal fluid. Clinical findings were compared between cases of meningitis and other children.

RESULTS

Of 2097 children between 2 months and 3 years of age investigated, 51 had a confirmed diagnosis of bacterial meningitis. In multivariate analysis using a model adjusting for age but not including respiratory signs, the variables associated independently with meningitis were appearance of being very sick (odds ratio for meningitis vs. no meningitis or no lumbar puncture performed (OR) 4.1, 95% CI 1.5-11.1), being lethargic or unconscious (OR 5.2, 95% CI 2.1-13), a stiff neck (OR 29.3, 95% CI 12.2-70.3), a bulging fontanel (OR 3.2, 95% CI 1.2-8.5) and reduced feeding as a prompted complaint (OR 2.9, 95% CI 1.3-6.7). A combination model of a history of convulsions, or being lethargic or unconscious, or having a stiff neck, as used in the WHO-Integrated Management of Childhood Illness (IMCI) guidelines, had a sensitivity of 98% and a specificity of 72% to predict meningitis.

CONCLUSIONS

A combination of a limited number of signs is sufficient to predict meningitis with high sensitivity, without a large number of children who do not have meningitis being unnecessarily referred.

Survival and sequelae of meningococcal meningitis in Ghana

BACKGROUND

Meningococcal meningitis epidemics are frequent in the Sahel zone of Africa but there is little information on the frequency of long-term sequelae. We analysed excess mortality in the two years following the 1997 epidemic in northern Ghana and carried out a case-control study to assess sequelae in the survivors.

METHODS

Two-year survival of 696 meningitis cases recorded at the War Memorial Hospital, Navrongo, was analysed using data from a demographic surveillance system. A structured questionnaire on disability and on psychiatric, neuropsychological and behavioural problems was administered to 505 of the survivors and 505 age- sex- and location-matched controls as well as to their respective relatives. Cases and controls underwent full neurological and neuropsychological examination and were evaluated for hearing impairment by audiometry.

RESULTS

Survival rates after the first month following the attack were similar in cases and controls. Hearing impairment was the major sequela, and was reported in 6 per cent of cases and 2 per cent of controls (odds ratio [OR] = 3.10; 95% CI : 1.48-7.09). Audiometry detected severe and profound hearing loss in the worse affected ear (> or =70 db) in 8/496 (1.6%) survivors but in only one control. Survivors of meningitis were more likely to suffer from feelings of tiredness (OR = 1.47; 95% CI : 1.03-2.11) and were more often reported by relatives to have insomnia (OR = 2.31; 95% CI : 1.17-4.82) and daily alcohol consumption.

INTERPRETATION

Meningococcal meningitis annually causes approximately 10 000 cases of deafness in sub-Saharan Africa; there is a need for early detection of affected survivors and promotion of simple hearing devices. There is a sizeable burden of depressive disorders secondary to meningitis which should be identified and looked after appropriately.

Policy analysis of the use of hepatitis B, Haemophilus influenzae type b-, Streptococcus pneumoniae-conjugate and rotavirus vaccines in national immunization schedules

After the development of national vaccine programmes to deliver six vaccines to infants, new vaccine adoption has been limited. Analysis of the health and economic implications of new vaccination options can help national policy-makers. Country specific quantitative policy analyses were conducted to estimate the impact of vaccination against hepatitis B (HB), Haemophilus influenzae type b (Hib), Streptococcus pneumoniae (SP) and rotavirus. Disease burden, programme costs and the potential reduction of disease from vaccination was assessed for each vaccine. Without vaccination, these four vaccine preventable diseases contribute up to 4.1 million deaths in each successive birth cohort. Routine scheduled use of HB and Hib vaccines could prevent up to 1.7 million deaths; SP and rotavirus vaccines, an additional 1.4 million deaths, annually. The global cost per life-year saved ranged from $29 to $150 with great variation by income and economic groups. With a few exceptions for a few countries, these vaccines would cost a fraction of average per-capita gross domestic product to save a life-year. The addition of HB and Hib vaccines, should be considered for integration in all national immunization programmes. SP and rotavirus vaccines, with the given assumptions, would also be cost-effective. Proactive analysis of the economic and epidemiologic impact of these vaccines can hasten their introduction into national vaccination schedules.

Risk factors for an adverse outcome in bacterial meningitis in the tropics: a reappraisal with focus on the significance and risk of seizures

The relationship of presentation to outcome in children with meningitis was analysed. The relative risk (95% confidence interval) of an adverse outcome (death or neurological sequelae) associated with presentation with at least three of ten features (age < or = 2 yrs, ill for > 7 days, antibiotic treatment, focal nerve deficits, abnormal posturing, abnormal muscle tone, lack of typical meningeal signs, shock, unrousable coma and seizures) was 4.9 (2.7, 8.8), p < 0.0001. The first six features were particularly associated with neurological sequelae, and shock and coma with death. Seizures were associated with either outcome. Two seizure types could be distinguished: seizures which occurred before or on diagnosis only (type I seizures) and seizures which occurred before and/or after diagnosis (type II seizures). Death occurred in 0/41 children without seizures and in 14/34 and 11/34 children with type I and type II seizures, respectively (p < 0.0001). Neurological sequelae occurred in 3/42 children without seizures and in 5/20 and 14/23 with type I and type II seizures, respectively (p < 0.0001).

Need for Haemophilus influenzae type b vaccination in Asia as evidenced by epidemiology of bacterial meningitis

OBJECTIVE

To evaluate the role of Haemophilus influenzae type b (Hib) infections in Asia by scrutinizing data on Hib meningitis.

DESIGN

A comprehensive literature search was performed in English and other languages. Special attention was paid to the age group of 0 to 4 years, in which the great majority of Hib meningitis occurs.

RESULTS

Twenty studies from as many countries indicated Hib to be a major pathogen in childhood meningitis. In series comprising nearly 2000 patients, Hib was responsible for at least 50% of cases in one-third of series and for at least 25% in three-fourths of series investigated and was the leading pathogen overall. The countries in South and Southeast Asia differed from the Middle East and East Asia in having a greater incidence of meningitis during the first 6 months of life; the proportions were 50 to 60% vs. 10 to 30%, respectively (P < 0.001).

CONCLUSIONS

Despite lacking data from many areas, belief in a paucity of Hib disease in Asia is not supported by the existing data; and because meningitis represents only 50 to 75% of all classical Hib manifestations and some cases occur after the age of 4 years, vaccination is warranted. The cumulative age curves suggest that conjugates with good immunogenic potential should be used, especially in South and Southeast Asia.

Haemophilus influenzae type b infections in Hong Kong

A 5-year territory-wide retrospective survey of invasive Haemophilus influenzae type b (Hib) diseases in Hong Kong established that the annual incidence for children <5 years old was 2.7 per 100000 [95% confidence interval (CI), 2.0 to 3.5]. However, the corresponding annual incidence in Vietnamese refugees in Hong Kong was 42.7 per 100000 (95% CI 17.2 to 87.9), giving a relative risk of 18.5 (95% CI 8.3 to 41.0). The nasopharyngeal carriage rate of Hib was zero in 621 healthy Chinese children and 1.3% (95% CI 0.04 to 2.63%) in 300 healthy Vietnamese refugees 2 months to 5 years old in Hong Kong. The corresponding carriage rate of nontypable H. influenzae was 5.8% (95% CI 1.4 to 7.6%) in Chinese and 65.4% (95% CI 58.9 to 69.8) in Vietnamese. In a larger study of 1812 healthy Chinese children between 6 months and 5 years of age investigated by throat swabs, again no Hib was isolated but 141 children (7.8%) were found to be carriers of nontype b H. influenzae. In a study of 596 healthy Chinese children and adults, 25% had the protective level of anti-Hib antibody of >0.15 microg/ml by 1 year and 90% had reached >0.15 microg/ml by 6 years of age. There was some evidence that these "natural" antibodies against Hib in Hong Kong Chinese were cross-reacting antibodies against antigens on other encapsulated bacteria.

An assessment of the value of Haemophilus influenzae type b conjugate vaccine in Asia

Haemophilus influenzae type b (Hib) is a leading cause of bacterial meningitis and pneumonia. Although invasive Hib disease has been reduced substantially wherever Hib conjugate vaccines have been introduced into routine childhood immunization schedules, these vaccines are more costly compared with the vaccines routinely used in the Expanded Program for Immunization. Consequently a model was constructed to compare the expected burden of Hib disease with and without a national vaccine program for various Asian countries. Cost of the vaccine program, expected benefits of reduced deaths and savings from prevented disease treatment were assessed for each country based on the model assumptions. Model outcomes were expressed as a net cost, cost per death prevented and cost per disability-adjusted life year for each country and economic stratum. With the assumption of a disease burden of meningitis and pneumonia comparable with that observed in other regions, the model predicts that 668000 cases of Hib pneumonia and 136000 cases of Hib meningitis would occur annually in this cohort resulting in 156000 deaths. Based on current vaccination coverage rates for the individual countries, the model predicted that approximately 136000 (87%) Hib deaths could be prevented annually with incorporation of Hib vaccine into the Expanded Program for Immunization. For each of the countries considered, routine vaccination with Hib would cost between 0.1 and 3.0% of per capita gross national product per child <5 years of age. Although Hib vaccine would be considered a cost-effective public health intervention, it may be cost-prohibitive to implement in the lowest income countries without initial donor assistance.

The rationale for population-based surveillance for Haemophilus influenzae type b meningitis

Although Haemophilus influenzae type b (Hib) conjugate vaccines have been spectacularly successful, nearly eradicating Hib disease in countries where used routinely, they are relatively expensive. In many countries the incidence of Haemophilus influenzae type b (Hib) disease is uncertain, and it is unclear whether the local burden of Hib disease warrants the costs of adding Hib vaccine to the routine immunization program. Population-based surveillance to assess the local burden of Hib disease can help decision makers with this process. Although pneumonia is more common than meningitis, surveillance for Hib meningitis and invasive disease is likely to be more feasible and efficient than surveillance for Hib pneumonia. Standardization of laboratory methods for the isolation and identification of H. influenzae from CSF specimens is essential to successful surveillance. Should a country decide to introduce Hib conjugate vaccine as a routine immunization, population-based surveillance data collected before and after the introduction of vaccine can be used to monitor its impact. Finally population-based surveillance for bacterial meningitis also can provide information on the incidence of pneumococcal and meningococcal infections and on serogroup or serotype distributions that will be important when evaluating the new vaccines for those pathogens that are being developed.

Haemophilus influenzae meningitis in Malaysia

OBJECTIVE

To determine the pattern of postneonatal childhood meningitis in Malaysia.

METHODS

Retrospective cross-sectional study involving five pediatric departments in Malaysia.

RESULTS

There were 435 cases of clinical meningitis admitted to the five centers. More than 90% of the patients were <5 years old, and one-half were <6 months of age. The estimated overall incidence of childhood meningitis in the first 5 years of life was 76.7 per 100000 per year. However, of the 435 cases only 71 (16.3%) fulfilled laboratory diagnostic criteria and in only 58 of these was an organism isolated. Nearly one-half (48%) of all bacteriologically proved cases were caused by Haemophilus influenzae type b (Hib). The mortality rate was 12.5% and 21 patients (30%) suffered neurologic sequelae.

CONCLUSIONS

More than one-half of all cases of culture-positive childhood bacterial meningitis were caused by Hib, although successful isolation of a pathogen occurred in only a small proportion of cases. For this reason the true incidence of Hib meningitis in Malaysia remains unknown. These findings are consistent with previous studies in Malaysia.

Study on Haemophilus influenzae type b diseases in China: the past, present and future

Meningitis caused by Haemophilus influenzae type b (Hib) is a common and serious disease for which there now are WHO-certified vaccines that are recommended for universal infant immunization in North America and European countries. If these vaccines are to be recommended in Asia, it is necessary to know the incidence, age distribution and clinical outcome of Hib meningitis and other systemic infections in this region. Data on Hib disease in China are scanty. Hib meningitis was common during the 1950s in China, accounting for up to 16% of all of pyogenic meningitis (up to 38% of cases were caused by unknown pathogens), despite severe epidemics of meningococcal meningitis during that period. Since 1989 we have conducted hospital- and community-based etiologic and epidemiologic studies of bacterial meningitis. Hib accounts for 30 to 50% of bacterial meningitis in China. The incidence of Hib meningitis in Hefei City was 10.4 per 100000 children <5 years, a result relatively lower than in the West but higher than the rate of 2.7 found in a retrospective study in Hong Kong. Pneumonia is the primary cause of death for Chinese children. From 1991 to 1993 the average mortality of children<5 years because of pneumonia was 1563.2 per 100000. To achieve the goal of reducing the death rate of children by one-third by the year 2000, greater efforts should be made to reduce the mortality of children with pneumonia. Our preliminary study showed that about one-fourth to one-third of cases of pneumonia in Chinese children might be caused by Hib. Therefore Hib vaccination for infants and children in China might be an effective and valuable procedure to achieve the goal.

Childhood non-traumatic coma in Kuala Lumpur, Malaysia

All post-neonatal children with acute non-traumatic coma admitted over an 8-month period were analysed and followed up for 18-24 months to determine the aetiology and outcome of their coma. One hundred and sixteen children, 72 boys and 44 girls, were recruited. Half the children were under 1 year of age and only 16 (14%) were more than 6 years of age. Eighty cases (69%) were due to infection, 15 (13%) to toxic metabolic causes, six (5%) to hypoxic ischaemic insults, four (3.5%) had intracranial haemorrhage, nine (7.8%) were due to miscellaneous causes and in two (1.7%) the cause was unknown. Seven cases were lost to follow-up. Of the remainder, 39 (35.7%) died, 32 (29.3%) developed permanent neurological deficit, and 38 (35%) were discharged well. The outcome was worst in the infectious group. Age of onset and sex did not significantly affect outcome. Our findings are similar to experience in Japan, where infection accounts for 74% of non-traumatic coma, but differ considerably from Western data on childhood coma where only a third of cases are due to infection.

Meningitis in Hong Kong children, with special reference to the infrequency of haemophilus and meningococcal infection

OBJECTIVE

To study the epidemiologic and aetiologic features of meningitis in children in Hong Kong.

METHODOLOGY

A retrospective study of 85 children resident in the New Territory East region of Hong Kong admitted to a teaching Hospital because of meningitis during a 9 year period.

RESULTS

Mycobacterium tuberculosis was the most common aetiological agent accounting for 13 cases (15.3%). Other bacteria accounted for 41 cases (48%); among these one fifth were caused by Haemophilus influenzae type b. The overall admission rates for tuberculous meningitis in Chinese children were 0.76/100,000 (95% CI 0.25-1.78) and 0.42/100,000 (CI 0.19-0.8) per year, respectively, for under 5 year olds and under 15 year olds. The overall annual incidence rates of bacterial meningitis other than tuberculous were 5.2/100,000 (CI 3.72-7.43) and 1.6/100,000 (CI 1.14-2.29) for Chinese children under 5 years and under 15 years, respectively. The annual incidence of H. influenzae meningitis in Chinese children under 5 years old was low at 1.1/100,000 (0.43-2.2). All five cases of meningococcal meningitis were in Vietnamese children (under 5 years of age incidence: 13.0/100,000 per year, CI 4.2-30.3). There were no cases of meningococcal meningitis in Chinese children during the 9 year period.

CONCLUSION

M. tuberculosis was the most common aetiological agent of meningitis in Hong Kong children. The incidence of haemophilus or meningococcal meningitis was very low.

Randomised trial of Haemophilus influenzae type-b tetanus protein conjugate vaccine [corrected] for prevention of pneumonia and meningitis in Gambian infants

BACKGROUND

In developing countries, pneumonia and meningitis due to Haemophilus influenzae type b (Hib) are common in children under age 12 months and the mortality from meningitis is high. Protein-polysaccharide conjugate vaccines have brought Hib disease under control in industrialised countries. We did a double-blind randomised trial in The Gambia to assess the efficacy of a Hib conjugate vaccine for the prevention of meningitis, pneumonia, and other invasive diseases due to Hib.

METHODS

Between March, 1993, and October, 1995, 42,848 infants were randomly allocated the conjugate vaccine Hib polysaccharide tetanus protein (PRP-T) mixed with diphtheria-tetanus-pertussis vaccine (DTP), or DTP alone at age 2 months, 3 months, and 4 months. Children who presented with signs of invasive Hib were investigated by blood culture and, where appropriate, by lumbar puncture, chest radiograph, or percutaneous lung aspirate. Children were followed up for between 5 and 36 months.

FINDINGS

The median ages at which children received the study vaccine were 11 weeks, 18 weeks, and 24 weeks. 83% of children enrolled received all three doses of vaccine. 17 cases of culture-positive Hib pneumonia, 28 of Hib meningitis, and five of other forms of invasive Hib disease were detected amongst the study children. The efficacy of the vaccine for the prevention of all invasive disease after three doses was 95% (PRP-T vaccinees 1, controls 19 [95% CI 67-100]), for the prevention of Hib pneumonia after two or three doses, 100% (vaccinees 0, controls 10 [55-100]), and for the prevention of radiologically defined pneumonia at any time after enrollment, 21.1% (PRP-T vaccinees 198, controls 251 [4.6-34.9]).

INTERPRETATION

PRP-T conjugate Hib vaccine prevented most cases of meningitis and pneumonia due to Hib in Gambian infants. The reduction in the overall incidence of radiologically defined pneumonia in PRP-T vaccinees suggests that about 20% of episodes of pneumonia in young Gambian children are due to Hib. The introduction of Hib vaccines into developing countries should substantially reduce childhood mortality due to pneumonia and meningitis.

Pyogenic meningitis in children in north-western Ethiopia

A 5-year retrospective study of all children with acute pyogenic meningitis admitted to a district hospital in north-western Ethiopia was carried out from 1990 to 1994. A total of 132 cases of pyogenic meningitis were identified. The causative bacteria were identified in 85 (64%) patients. The most common pathogen was Haemophilus influenzae (40%) with a case fatality rate of 29.4%, followed by Neisseria meningitidis (36.4%), which had a case fatality rate of 16.1%, and Streptococcus pneumoniae (20%) with a case fatality rate of 35.3%. Boys accounted for 64% of the patients, giving a male:female ratio of 1.7:1. Median patient age was 0.75 years, and median ages of those infected by H. influenzae, N. meningitidis, and S. pneumoniae were 0.5, 4.0 and 0.6 years, respectively. The overall case fatality rate was 28%. The mortality rate of children below the age of 1 year was 38.4% and 13.8% for those above 1 year.

Invasive Haemophilus influenzae type b infections in children hospitalized in Hong Kong, 1986-1990. Hong Kong Hib Study Group

A 5-year territory-wide retrospective survey of invasive Haemophilus influenzae type b diseases was conducted in Hong Kong. Between 1986 and 1990, 57 cases (28 male) were recorded in children less than 12 years old (37 cases of meningitis, 9 of septicaemia and 11 of bacteraemic pneumonia). The annual incidence for children less than 5 years old was 2.7 per 10(5) (95% confidence interval (CI) 2.0-3.5). Of the 57 cases, 39 were Chinese and 18 non-Chinese (7 Vietnamese refugees, 6 Caucasians, 5 others). The annual incidence in Vietnamese refugees less than 5 years old was 42.7 per 10(5) (95% CI 17.2-87.9), giving a relative risk of 18.5 (95% CI 8.3-41.0). Chinese patients (68%) were under-represented as Chinese accounted for at least 94% of the population. Moreover, 14 of the 39 Chinese patients had pre-existing medical problems, compared with only 1 of the 18 non-Chinese patients patients had pre-existing medical problems, compared with only 1 of the 18 non-Chinese patients (p = 0.022).

Pattern and antibiotic susceptibility of bacteria in pyogenic meningitis in a children's emergency room population in Maiduguri, Nigeria, 1988-1992

From January 1988 to November 1992, 107 (3.5%) of 3074 postneonatal children admitted to the Children's Emergency Room, University of Maiduguri Teaching Hospital, Nigeria, had sporadic pyogenic meningitis; 66 (61.7%) were aged < or = 12 months. Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae together were responsible for 77.3% (58) of 75 culture-proven cases, 13.4% (10) had Enterobacteriaceae, 5.3% (4) had Staphylococcus aureus and 4% (3) untyped alpha-haemolytic streptococci. Fifty percent of 62 bacteria were resistant to ampicillin, 47.2% of 36 to penicillin and 10.7% of 56 to chloramphenicol; none of 21 bacteria was simultaneously resistant to all three antibiotics. Up until 1992, we have encountered treatment failure with a regimen containing chloramphenicol in only 2 of 53 patients; the 2 patients had coliform meningitis. Non-meningococcal bacteria are an important cause of sporadic pyogenic meningitis in sub-Saharan Nigeria and chloramphenicol is the most appropriate initial drug of choice at the present time for the management of sporadic meningitis.

Presenting features of bacterial meningitis in young infants

More guidance is required in the management of acutely ill, febrile young infants. Of 94 young infants undergoing lumbar puncture (LP) as part of their management, 26 of the 60 (43.3%) presenting with seizures and fever and six of the 34 (17.7%) without seizures had bacterial meningitis (BM) (relative risk (95% confidence interval) = 2.46 (1.12, 5.37), p = 0.012). Except for the presence of a bulging fontanelle and focal seizures, no other presenting signs or symptoms were significantly associated with BM; seven of the 26 infants with BM who presented with seizures and two of the six without seizures lacked a bulging fontanelle. Overall, the ratio of BM to other illnesses was 1:1.94; of those with BM, 13 of the 32 (40.6%) had co-existing acute respiratory infections and four of the 32 (12.5%) had asexual malaria parasitaemia. Seizures with fever are an important presenting feature of BM in young infants and a screening LP should be considered mandatory to confirm or exclude BM in febrile young infants with seizures, unless certain contraindications apply.

Purulent meningitis in children: outcome using a standard management regimen with chloramphenicol

We report a prospective study of 108 children aged from 2 weeks to 10 years with purulent meningitis admitted to the children's wards of Port Moresby General Hospital, 105 of whom were treated with a standard management regimen using chloramphenicol (given intramuscularly initially) as the only antibiotic. The case fatality rate of 16.7% and the apparently low morbidity rate were felt to be very satisfactory in a high risk population. The medical officers' compliance with the standard antibiotic regimen was good, but was disappointing for the use of anticonvulsants. The presence of convulsions before admission or at any time in the illness, coma on admission, and a history of illness of more than 3 days duration prior to admission were strongly associated with death. We believe phenobarbitone should be given prophylactically to children less than 2 years of age who have meningitis. Further improvements in outcome are likely to be achieved not by changes in antibiotic policy but by improving early diagnosis and basic supportive care, and by preventing convulsions.