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Featured researches published by Audrey Michael.


The Lancet | 2002

Chloramphenicol versus benzylpenicillin and gentamicin for the treatment of severe pneumonia in children in Papua New Guinea: a randomised trial

Trevor Duke; Harry Poka; Frank Dale; Audrey Michael; Joyce Mgone; Tilda Wal

BACKGROUND Pneumonia is the most frequent cause of child mortality in less-developed countries. We aimed to establish whether the combination of benzylpenicillin and gentamicin or chloramphenicol would be better as first-line treatment in children with severe pneumonia in Papua New Guinea. METHODS We did an open randomised trial in which we enrolled children aged 1 month to 5 years of age who fulfilled the WHO criteria for very severe pneumonia and who presented to hospitals in two provinces. Children were randomly assigned to receive chloramphenicol (25 mg/kg 6 hourly) or benzylpenicillin (50 mg/kg 6 hourly) plus gentamicin (7.5 mg/kg daily) by intramuscular injection. The primary outcome measure was a good or an adverse outcome. FINDINGS 1116 children were enrolled; 559 children were treated with chloramphenicol and 557 with benzylpenicillin and gentamicin. At presentation the median haemoglobin oxygen saturation was 71% (IQR 57-77) for those allocated chloramphenicol and 69% (55-77) for those allocated penicillin and gentamicin. 147 (26%) children treated with chloramphenicol and 123 (22%) treated with penicillin and gentamicin had adverse outcomes (p=0.11). 36 children treated with chloramphenicol and 29 treated with penicillin and gentamicin died. More children treated with chloramphenicol than penicillin and gentamicin represented with severe pneumonia within 1 month of hospital discharge (p=0.03). INTERPRETATION For children with severe pneumonia in less-developed countries the probability of a good outcome is similar if treated with chloramphenicol or with the combination of benzylpenicillin and gentamicin.


Bulletin of The World Health Organization | 2002

Etiology of child mortality in Goroka, Papua New Guinea: a prospective two-year study

Trevor Duke; Audrey Michael; Joyce Mgone; Dale Frank; Tilda Wal; Rebecca Sehuko

OBJECTIVE To collect accurate data on disease- and microbial-specific causes and avoidable factors in child deaths in a developing country. METHODS A systematic prospective audit of deaths of children seen at Goroka Hospital in the highlands of Papua New Guinea was carried out. Over a 24-month period, we studied 353 consecutive deaths of children: 126 neonates, 186 children aged 1-59 months, and 41 children aged 5-12 years. FINDINGS The most frequent age-specific clinical diagnoses were as follows: for neonates--very low birth weight, septicaemia, birth asphyxia and congenital syphilis; for children aged 1-59 months--pneumonia, septicaemia, marasmus and meningitis; and for children aged 5-12 years--malignancies and septicaemia. At least one microbial cause of death was identified for 179 (50.7%) children and two or more were identified for 37 (10.5%). Nine microbial pathogens accounted for 41% of all childhood deaths and 76% of all deaths that had any infective component. Potentially avoidable factors were identified for 177 (50%) of deaths. The most frequently occurring factors were as follows: no antenatal care in high-risk pregnancies (8.8% of all deaths), very delayed presentation (7.9%), vaccine-preventable diseases (7.9%), informal adoption or child abandonment leading to severe malnutrition (5.7%), and lack of screening for maternal syphilis (5.4%). Sepsis due to enteric Gram-negative bacilli occurred in 87 (24.6%). The strongest associations with death from Gram- negative sepsis were adoption/abandonment leading to severe malnutrition, village births, and prolonged hospital stay. CONCLUSIONS Reductions in child mortality will depend on addressing the commonest causes of death, which include disease states, microbial pathogens, adverse social circumstances and health service failures. Systematic mortality audits in selected regions where child mortality is high may be useful for setting priorities, estimating the potential benefit of specific and non-specific interventions, and providing continuous feedback on the quality of care provided and the outcome of health reforms.


Archives of Disease in Childhood | 2003

Chloramphenicol or ceftriaxone, or both, as treatment for meningitis in developing countries?

Trevor Duke; Audrey Michael; Tilda Wal; J Reeder

Aims: To determine in children with meningitis whether there is any difference in mortality and neurological sequelae using chloramphenicol as first line treatment, with a change to ceftriaxone if chloramphenicol resistance is shown in vitro, compared to using ceftriaxone as first line treatment, with a change to chloramphenicol if there is no evidence of in vitro resistance. Methods: An observational study with a retrospective control group nested within a randomised trial of fluid management for bacterial meningitis where clinical care was standardised. Chloramphenicol is standard treatment for bacterial meningitis in Papua New Guinea. In the first 150 cases we used chloramphenicol and only changed treatment to ceftriaxone if chloramphenicol resistance for cerebrospinal fluid isolates was proved. After finding 20% of Haemophilus influenzae were resistant to chloramphenicol, and that most affected children had poor outcomes, we changed to an alternative strategy. In the next 196 cases first line treatment was ceftriaxone and treatment was changed to chloramphenicol if the isolated bacteria were found to be susceptible. Results: When chloramphenicol was used as first line treatment for meningitis followed by ceftriaxone when in vitro resistance was shown, there was invariably a very poor outcome in chloramphenicol resistant disease (71% of children died or had severe neurological complications). Using ceftriaxone as first line treatment was effective in reducing mortality and neurological sequelae from chloramphenicol resistant Haemophilus influenzae type (71% v 9%, relative risk 0.13; 95% CI 0.02 to 0.87; p = 0.013). Changing to chloramphenicol if there was no evidence of in vitro resistance was less than half the cost of empirical use of ceftriaxone for a full course for all children with meningitis. Conclusions: Using a third generation cephalosporin as first line treatment is effective in dealing with the problem of poor outcomes from meningitis due to Haemophilus influenzae that is resistant to chloramphenicol, and a strategy of changing to chloramphenicol if in vitro susceptibility is shown will reduce the use of expensive third generation cephalosporins without comprising on clinical outcomes. This highlights the urgent need to reduce the costs of third generation cephalosporins, to improve bacteriological services in developing countries, and to introduce effective and affordable vaccines against H influenzae and Streptococcus pneumoniae.


Annals of Tropical Paediatrics | 2002

Management of meningitis in children with oral fluid restriction or intravenous fluid at maintenance volumes: a randomised trial

Trevor Duke; Dale Frank; Audrey Michael; Theresa Paulo; Joyce Mgone; Jonah Kurubi

Abstract A multi-centre randomised open trial was done to determine whether moderate oral fluid restriction or intravenous fluid at full maintenance volumes would result in a better outcome for children with bacterial meningitis in Papua New Guinea, and what clinical signs could guide fluid management. Children with clinical signs and cerebrospinal fluid suggestive of bacterial meningitis received either breast milk by nasogastric tube at 60% of normal maintenance volumes (n=172) or intravenous half-normal saline and 5% dextrose at 100% of normal maintenance volumes (n=174) for the 1st 48 hrs of treatment. An adverse outcome was death or severe neurological sequelae, and a good outcome was defined as intact survival or survival with at worst mild-to-moderate neurological sequelae. The probability of an adverse outcome was 24.7% in the intravenous group and 33.1% in the oral-restricted group, but the difference was not statistically significant (RR 0.75, 0.53-1.04, p=0.08). Sunken eyes or reduced skin turgor at presentation were risk factors for an adverse outcome (OR 5.70, 95% CI 2.87-11.29) and were most strongly associated with adverse outcome in the fluid-restricted group. Eyelid oedema during treatment was also a risk factor for an adverse outcome (OR 2.54, 95% CI 1.36-4.75) and eyelid oedema was much more common in the intravenous group (26%) than in the restricted group (5%). For many children with bacterial meningitis in less developed countries, moderate fluid restriction is unnecessary and will be harmful; a normal state of hydration should be achieved but over-hydration should be avoided. Giving 100% of normal maintenance fluids, especially with intravenous hypotonic fluid, will lead to oedema in up to one quarter of children with bacterial meningitis. If additional intravenous fluids are required for children with meningitis, an isotonic solution should be used.


Clinical and Vaccine Immunology | 2009

Maternal Antibodies to Pneumolysin but Not to Pneumococcal Surface Protein A Delay Early Pneumococcal Carriage in High-Risk Papua New Guinean Infants

Jacinta P. Francis; Peter Richmond; William Pomat; Audrey Michael; Helen Keno; Suparat Phuanukoonnon; Jan B. Nelson; Melissa Whinnen; Tatjana Heinrich; Wendy-Anne Smith; Susan L. Prescott; Patrick G. Holt; Peter Siba; Deborah Lehmann; Anita H. J. van den Biggelaar

ABSTRACT Immunization of pregnant women can be an efficient strategy to induce early protection in infants in developing countries. Pneumococcal protein-based vaccines may have the capacity to induce pneumococcal serotype-independent protection. To understand the potential of maternal pneumococcal protein-specific antibodies in infants in high-risk areas, we studied the placental transfer of naturally acquired antibodies to pneumolysin (Ply) and pneumococcal surface protein A family 1 and 2 (PspA1 and PspA2) in relation to onset of pneumococcal nasopharyngeal carriage in infants in Papua New Guinea (PNG). In this study, 76% of the infants carried Streptococcus pneumoniae in the upper respiratory tract within the first month of life, at a median age of 19 days. Maternal and cord blood antibody titers to Ply (ρ = 0.824, P < 0.001), PspA1 (ρ = 0.746, P < 0.001), and PspA2 (ρ = 0.631, P < 0.001) were strongly correlated. Maternal pneumococcal carriage (hazard ratio [HR], 2.60; 95% confidence interval [CI], 1.25 to 5.39) and younger maternal age (HR, 0.74; 95% CI, 0.54 to 1.00) were independent risk factors for early carriage, while higher cord Ply-specific antibody titers predicted a significantly delayed onset (HR, 0.71; 95% CI, 0.52 to 1.00) and cord PspA1-specific antibodies a significantly younger onset of carriage in PNG infants (HR, 1.57; 95% CI, 1.03 to 2.40). Maternal vaccination with a pneumococcal protein-based vaccine should be considered as a strategy to protect high-risk infants against pneumococcal disease by reducing carriage risks in both mothers and infants.


Pediatric Infectious Disease Journal | 1999

Bacterial and viral etiology of severe infection in children less than three months old in the highlands of Papua New Guinea

Deborah Lehmann; Audrey Michael; Omena M; Clegg A; Lupiwa T; Sanders Rc; Marjen B; Wai'in P; Rongap A; Saleu G; P. Namuigi; M. Kakazo; S. Lupiwa; Lewis Dj; Michael P. Alpers

OBJECTIVE Determine the bacterial and viral etiology of severe infection in young Papua New Guinean infants as part of a multicenter study in four developing countries aimed at improving case management guidelines. METHODS Between March, 1991, and April, 1993, children aged <3 months were recruited at the outpatient department of Goroka Base Hospital, Papua New Guinea (PNG). Children with pre-defined inclusion criteria were enrolled, a history was taken and clinical examination was performed. Blood and urine were collected from children with signs suggestive of severe disease together with eye, umbilical and pernasal swabs as appropriate. Nasopharyngeal aspirates (NPAs) were collected from children with and without signs of severe disease for identification of viruses and Chlamydia trachomatis by direct fluorescent antibody staining. RESULTS 3280 infants were triaged and 2168 enrolled, among whom 968 had signs suggestive of severe disease. Group A Streptococcus (Streptococcus pyogenes) and Staphylococcus aureus were the most important bacterial pathogens isolated from children < 1 month old with severe infections, and Streptococcus pneumoniae, S. pyogenes and Staphylococcus aureus were most important in older children. Of 292 eye swabs 19 (7%) grew Neisseria gonorrhoeae. Of 116 umbilical swabs 51 (44%) grew S. pyogenes and 45 (39%) grew Staphylococcus aureus. Respiratory syncytial virus was the most important viral cause of acute lower respiratory infection. CONCLUSIONS S. pyogenes, S. pneumoniae and Staphylococcus aureus are important causes of severe infection in young children in the PNG highlands. It is necessary to improve access to clean water, promote hand-washing in the hospital and at home and investigate further the use of maternal immunization for the prevention of severe disease in young infants.


Pediatric Infectious Disease Journal | 2012

Effect of early carriage of streptococcus pneumoniae on the development of pneumococcal protein-specific cellular immune responses in infancy

Anita H. J. van den Biggelaar; William Pomat; Suparat Phuanukoonnon; Audrey Michael; Celestine Aho; Marie A. Nadal-Sims; Catherine J. Devitt; Peter Jacoby; Belinda J. Hales; Wendy-Anne Smith; Timothy J. Mitchell; Selma P. Wiertsema; Peter Richmond; Peter Siba; Patrick G. Holt; Deborah Lehmann

Background: The aim of this study was to examine the relationship between nasopharyngeal pneumococcal colonization in early life and the subsequent development of pneumococcal-specific T cell responses. Methods: Pernasal swabs were collected from Papua New Guinean infants at the ages of 1 and 2 weeks (n = 279). At 9 months, in vitro cellular immune responses to choline-binding protein A (n = 132), pneumococcal surface protein A (n = 132), pneumolysin (n = 99), and the pneumococcal conjugate vaccine carrier CRM197 were determined. Responses were compared based on the childrens carriage status within the first 2 weeks of life. Results: Within the first 2 weeks of life, 40% of the study children carried Streptococcus pneumoniae. Early carriage was associated with lower interferon-&ggr; and interleukin 10 responses to pneumococcal proteins at age 9 months when children had not received pneumococcal conjugate vaccines during the study period. Conclusions: Early pneumococcal carriage may result in enhanced disease susceptibility and suboptimal vaccine responses by modulating the development of pneumococcal immune responses.


American Journal of Tropical Medicine and Hygiene | 2012

Predictors of Acute Bacterial Meningitis in Children from a Malaria-Endemic Area of Papua New Guinea

Moses Laman; Laurens Manning; Andrew R. Greenhill; Trevor Mare; Audrey Michael; Silas Shem; John Vince; William Lagani; Ilomo Hwaiwhanje; Peter Siba; Ivo Mueller; Timothy M. E. Davis

Predictors of acute bacterial meningitis (ABM) were assessed in 554 children in Papua New Guinea 0.2-10 years of age who were hospitalized with culture-proven meningitis, probable meningitis, or non-meningitic illness investigated by lumbar puncture. Forty-seven (8.5%) had proven meningitis and 36 (6.5%) had probable meningitis. Neck stiffness, Kernigs and Brudzinskis signs and, in children < 18 months of age, a bulging fontanel had positive likelihood ratios (LRs) ≥ 4.3 for proven/probable ABM. Multiple seizures and deep coma were less predictive (LR = 1.5-2.1). Single seizures and malaria parasitemia had low LRs (≤ 0.5). In logistic regression including clinical variables, Kernigs sign and deep coma were positively associated with ABM, and a single seizure was negatively associated (P ≤ 0.01). In models including microscopy, neck stiffness and deep coma were positively associated with ABM and parasitemia was negatively associated with ABM (P ≤ 0.04). In young children, a bulging fontanel added to the model (P < 0.001). Simple clinical features predict ABM in children in Papua New Guinea but malaria microscopy augments diagnostic precision.


Antimicrobial Agents and Chemotherapy | 2011

Increasing chloramphenicol resistance in Streptococcus pneumoniae isolates from Papua New Guinean children with acute bacterial meningitis

Laurens Manning; Moses Laman; Andrew R. Greenhill; Audrey Michael; Peter Siba; Ivo Mueller; Timothy M. E. Davis

ABSTRACT In Papua New Guinean (PNG) children with acute bacterial meningitis (ABM), all Haemophilus influenzae isolates were resistant to chloramphenicol. Although Streptococcus pneumoniae isolates had a median chloramphenicol MIC of 3 μg/ml, it was ≥4 μg/ml in 42.8%, and the likelihood of an area under the 24-hour concentration-time curve/MIC ratio of >100 h at a MIC of ≥4 μg/ml was approximately 50%. All isolates were ceftriaxone sensitive. These data support ceftriaxone rather than conventional chloramphenicol for all PNG children with suspected ABM.


Annals of Tropical Paediatrics | 1993

Antigenuria in healthy Papua New Guinean children with nasal Haemophilus influenzae type b carriage

Mark J. Manary; Deborah Lehmann; Audrey Michael; Keith Coakley; John Taime; Janet Montgomery; Dan M. Granoff

In 100 healthy children under the age of 3 years living in the vicinity of Goroka, Papua New Guinea, the nares were cultured for Haemophilus influenzae type b (Hib), and a urine sample was obtained for measurement of Hib polysaccharide (PS) by ELISA. Hib carriage was detected in nine children and Hib PS was detected in the urine of 11. Hib PS was found in seven of nine Hib nasal carriers compared with four of 91 healthy children without Hib in their nares (p < 0.001). The range of urine antigen concentrations in the two groups was similar (0.6 to 2.7 ng/ml). The relative risk of antigenuria in the carriers, compared with the children with negative nares cultures, was 58 (95% confidence interval, 10.5-324). These data extend previous observations from Hib carriers studied in the United States and show that Hib carriage in children from a developing country is associated with antigenuria. Further studies are needed to determine whether carriers and patients can be differentiated by differences in the magnitude of the concentration of Hib PS excreted in urine.

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Deborah Lehmann

University of Western Australia

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Peter Siba

Papua New Guinea Institute of Medical Research

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Andrew R. Greenhill

Federation University Australia

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William Pomat

Papua New Guinea Institute of Medical Research

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Michael P. Alpers

Papua New Guinea Institute of Medical Research

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Peter Richmond

University of Western Australia

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Trevor Duke

Royal Children's Hospital

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Janet Montgomery

Papua New Guinea Institute of Medical Research

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Jacinta P. Francis

Papua New Guinea Institute of Medical Research

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Mition Yoannes

Papua New Guinea Institute of Medical Research

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