Mahomed Patel

Effect of Infection Control Measures on the Frequency of Upper Respiratory Infection in Child Care: A Randomized, Controlled Trial

Background. Acute upper respiratory infections are common in children who attend child care, and preventing transmission of disease in this setting depends on actions by child care staff. We set out to discover whether transmission of respiratory infections in child care could be reduced by improved infection control procedures. Methods. We performed a cluster, randomized, controlled trial of an infection control intervention conducted in child care centers in 1 city in Australia. The intervention was training of child care staff about transmission of infection, handwashing, and aseptic nosewiping technique. Implementation of the intervention was recorded by an observer. Illness was measured by parent report in telephone interviews every 2 weeks. Results. There were 311 child-years of surveillance for respiratory symptoms. By multivariable analysis, there was no significant reduction in colds in intervention center children across the full age range. However, a significant reduction in respiratory illness was present in children 24 months of age and younger. When compliance with infection control practices was high, colds in these children were reduced by 17%. Conclusions. This trial supports the role of direct transmission of colds in young children in child care. The ability of infection control techniques to reduce episodes of colds in children in child care was limited to children 24 months of age and under.

Effect of Infection Control Measures on the Frequency of Diarrheal Episodes in Child Care: A Randomized, Controlled Trial

Background. Diarrheal infections are common in children who attend child care, and preventing transmission of disease in this setting depends on actions by child care staff. We set out to discover whether transmission of gastrointestinal infections in child care could be reduced by improved infection control procedures. Methods. We performed a cluster randomized, controlled trial of an infection control intervention conducted in child care centers for 1 city in Australia. The intervention was training of child care staff about transmission of infection and handwashing and focused on both staff and child behavior. Implementation of the intervention was recorded by an observer. Illness was measured by parent report in telephone interviews every 2 weeks. Results. There were 311 child-years of surveillance for diarrheal episodes. The rate of episodes of diarrhea was 1.9 per child-year in intervention centers and 2.7 per child-year in control centers. Multivariable analysis showed that diarrheal episodes were significantly reduced in intervention center children by 50%. However, the impact of the intervention was confined to children over 24 months of age. For those centers in which childrens compliance with handwashing was high, diarrheal episodes were reduced by 66%. Conclusions. This trial supports education about infection control, for staff and children in child care, as a means of reducing transmission of diarrhea. Reduction in episodes of diarrhea in children in child care was limited to children over 24 months of age.

Internationally Distributed Frozen Oyster Meat Causing Multiple Outbreaks of Norovirus Infection in Australia

BACKGROUND Between November 2003 and January 2004, outbreaks of norovirus in 3 Australian jurisdictions involving 83 cases of illness were associated with imported oyster meat. METHODS Cohort studies were conducted in 2 jurisdictions to identify relative risks of illness for the consumption of oysters. A case series was conducted in the third jurisdiction. RESULTS The cohort studies conducted in the first 2 jurisdictions identified relative risks of illness of 17 (95% confidence interval, 5-51) and 35 (95% confidence interval, 5-243), respectively, for the consumption of oysters. Multiple strains of norovirus were detected in fecal specimens from 8 of 14 patients and in 1 of the 3 batches of implicated oyster meat using seminested reverse-transcriptase polymerase chain reaction methods. Traceback investigations revealed that all oyster meat was harvested from the same estuary system in Japan within the same month. CONCLUSIONS These outbreaks demonstrate the potential of foodborne disease to spread internationally and the need for national and international collaboration to investigate such outbreaks. Foodborne illness related to norovirus is underestimated because of underreporting of human cases and challenges in laboratory detection of viruses in foods, both of which can delay public health action.

Low-Level Fluoroquinolone Resistance among Campylobacter jejuni Isolates in Australia

BACKGROUND Ciprofloxacin-resistant Campylobacter jejuni isolates obtained from infected patients in Australia have not been detected in studies of isolates from specific geographic areas. The Australian government has prohibited the use of fluoroquinolone in food-producing animals. To assess the impact of this policy, we have examined the antimicrobial susceptibility of isolates from 5 Australian states. METHODS We conducted a period-prevalence survey of the susceptibility of C. jejuni isolates to 10 antimicrobial agents. C. jejuni isolates obtained from 585 patients from 5 Australian states (Queensland, South Australia, Tasmania, Victoria, and Western Australia) were identified by means of notifiable disease databases and were systematically selected from September 2001 to August 2002. RESULTS Among locally acquired infections, only 2% of isolates (range, 0%-8% in different states) were resistant to ciprofloxacin. The locally acquired isolates also exhibited resistance to sulfisoxazole (55%), ampicillin (46%), roxithromycin (38%), tetracycline (7%), nalidixic acid (6%), chloramphenicol (3%), erythromycin (3%), gentamicin (2%), and kanamycin (0.2%). Treatment with antimicrobial agents in the 4 weeks before onset was not associated with ciprofloxacin resistance. CONCLUSIONS The very low level of ciprofloxacin resistance in C. jejuni isolates likely reflects the success of Australias policy of restricting use of fluoroquinolones in food-producing animals.

Evaluating the use of penicillin to control outbreaks of acute poststreptococcal glomerulonephritis.

INTRODUCTION Outbreaks of acute poststreptococcal glomerulonephritis (APSGN), occur every few years in remote Australian Aboriginal communities. Intervention with benzathine penicillin G (BPG) to all children is effective in reducing streptococcal carriage in a community, but its effectiveness in arresting outbreaks of APSGN has not been established. OBJECTIVE To study nine recent community outbreaks of APSGN in Australias Northern Territory and compare them with outbreaks reported in the literature to assess the impact of intervention with BPG. METHODS Because randomized controlled trials have not been conducted for this purpose, we assessed data from published observational studies and relevant experiences in the Northern Territory (NT). Eight of the nine outbreaks in the NT were studied prospectively. An outbreak was defined as two or more clinical cases of APSGN occurring within 1 week in a single community. Three intervention methods were used: intramuscular BPG to all children ages 3 to 15 years; BPG only to children with skin lesions; and BPG only to child contacts of clinical cases. The attack rates, number of clinical cases before and after the interventions were documented and the coverage of children with penicillin were estimated. RESULTS A review of the literature found very little evidence either for or against the effectiveness of intervention with BPG. In our study four communities used the first method of intervention. The community with the lowest uptake of penicillin continued to have cases in untreated children for 9 further weeks, two communities had no new cases from 3 weeks after the intervention and the fourth had a single further case after 4 weeks. The one community that used the second method had a high initial attack rate but no further cases from 1 week after the intervention. Three communities used the third method and in one community no intervention was attempted. CONCLUSION Our observational study supports the use of BPG in the community to prevent new cases of APSGN. It suggests that targeted treatment of children with skin sores and household contacts of cases, rather than attempted treatment of all children in the community, could be an effective method of intervention.

The impact of pneumococcal conjugate vaccine on rates of myringotomy with ventilation tube insertion in Australia.

Background: In randomized controlled trials and postmarketing studies the heptavalent pneumococcal conjugate vaccine (7vPCV) has been shown to reduce myringotomy with ventilation tube insertion (MVTI) procedures in a 4-dose schedule. In Australia, a 3-dose schedule at 2, 4, and 6 months of age is routinely used in non-Indigenous children. Our aim was to determine if a reduction in MVTI comparable to that documented in the United States occurred in Australia despite the absence of the booster dose. Methods: All episodes of MVTI in Australia from July 1998 to June 2007 among children aged ≤9 years were identified in an electronic database of national hospitalization records, including the public and private sectors. Age-stratified rates of MVTI before and after introduction of 7vPCV into the national immunization program in 2005 were determined, with Poisson regression modeling used to determine the vaccine impact after adjusting for background and seasonal trends. Results: A total of 238,634 hospital separations were identified. In the 2.5 years after routine 7vPCV introduction, there was a significant adjusted reduction in MVTI in children aged <1, 1, and 2 years of 23%, 16%, and 6%, respectively. A nonsignificant reduction was observed in those aged 3 and 4 years, while a significant increase of 5% was observed for the 5- to 9-year age group. Conclusions: Although ecologic data such as this have limitations, the significant differential effects observed by time period and age group are suggestive of a vaccine effect of similar magnitude to that documented by postmarketing surveillance in the United States. The rapid uptake of 7vPCV in Australia, including catch up to 2 years of age, is an important difference to the United States and it is possible that an even greater effect would have been observed with a booster dose in the second year of life. Longer term data will be needed to fully assess the role of a booster dose.

A cluster of meningococcal disease in western Sydney, Australia initially associated with a nightclub

Fourteen cases of meningococcal disease (MD) occurred in August September 1996 in western Sydney, Australia. Seven of the 10 young adults affected had a direct or indirect link with a local nightclub. Ten of 11 systemic meningococcal isolates had the phenotype C:2a:P1.5 and showed close genetic relationship by pulsed-field gel electrophoresis (PFGE). Organisms of this phenotype have not previously caused outbreaks in Australia, but have been associated with outbreaks and hyperendemic serogroup C MD in Europe, Canada, and the United States. This is the largest cluster of serogroup C MD reported in urban Australia, and the first involving a nightclub. The strain differentiation results were available rapidly enough to augment epidemiological investigations on a daily basis. Public health staff could thus establish links between cases quickly, follow the spread of new cases in the community, give accurate information to health officials and the press, and utilize existing knowledge about the characteristics of this phenotype to predict likely developments during the outbreak and afterwards. The strain differentiation data was also very helpful when the role of vaccination was considered, and existing guidelines on the management of outbreaks of MD could be used effectively for the first time in western Sydney.

Rumor surveillance and avian influenza H5N1

We describe the enhanced rumor surveillance during the avian influenza H5N1 outbreak in 2004. The World Health Organization’s Western Pacific Regional Office identified 40 rumors; 9 were verified to be true. Rumor surveillance informed immediate public health action and prevented unnecessary and costly responses.

General Practice and Pandemic Influenza: A Framework for Planning and Comparison of Plans in Five Countries

Background Although primary health care, and in particular, general practice will be at the frontline in the response to pandemic influenza, there are no frameworks to guide systematic planning for this task or to appraise available plans for their relevance to general practice. We aimed to develop a framework that will facilitate planning for general practice, and used it to appraise pandemic plans from Australia, England, USA, New Zealand and Canada. Methodology/Principal Findings We adapted the Haddon matrix to develop the framework, populating its cells through a multi-method study that incorporated the peer-reviewed and grey literature, interviews with general practitioners, practice nurses and senior decision-makers, and desktop simulation exercises. We used the framework to analyse 89 publicly-available jurisdictional plans at similar managerial levels in the five countries. The framework identifies four functional domains: clinical care for influenza and other needs, public health responsibilities, the internal environment and the macro-environment of general practice. No plan addressed all four domains. Most plans either ignored or were sketchy about non-influenza clinical needs, and about the contribution of general practice to public health beyond surveillance. Collaborations between general practices were addressed in few plans, and inter-relationships with the broader health system, even less frequently. Conclusions This is the first study to provide a framework to guide general practice planning for pandemic influenza. The framework helped identify critical shortcomings in available plans. Engaging general practice effectively in planning is challenging, particularly where governance structures for primary health care are weak. We identify implications for practice and for research.

Differing serologic responses to an Haemophilus influenzae type b polysaccharide-Neisseria meningitidis outer membrane protein conjugate (PRP-OMPC) vaccine in Australian Aboriginal and Caucasian infants - implications for disease epidemiology.

This study compared Hib antibody responses to a single lot of PRP-OMPC vaccine given at 2, 4 and 12 months to 57 Aboriginal infants in rural areas of the Northern Territory and 56 Caucasian infants in Sydney, Australia. The Aboriginal infants had lower levels of antibody in cord blood (P>0.05), which were significantly lower (P<0.02) by 2 months of age. Antibody responses to one or two doses of vaccine, measured at 4 and 12 months of age, were similar but the geometric mean titre following the booster dose in Aboriginal infants was significantly lower (1.98 vs. 6.04 mcg/ml, P = 0.002). Low preimmunisation antibody is consistent with the early onset of Hib disease in Aboriginal infants before immunisation. Lower responses to boosting could correlate with persistence of Hib colonisation in indigenous populations.