Planning for pandemic influenza surveillance in NSW.

Early detection of a novel strain (genotype) of influenza virus in the NSW population is the key to controlling a pandemic. If this occurs, ongoing surveillance will help determine the epidemiology and risk factors of the virus as well as its impact on essential services. Important components of surveillance preparedness in NSW include: border surveillance; hospital-based screening for suspected cases; protocols for efficient transport and testing of viral specimens; flexible, robust electronic tools for rapid surveillance data collection; management and reporting; and creation of surveillance surge capacity.

Indirect fluorescent antibody testing of nasopharyngeal swabs for influenza diagnosis in lung transplant recipients.

BACKGROUND: Rapid and reliable diagnosis of respiratory viral infections (RVI) in lung transplant recipients is essential to direct therapy of acute graft dysfunction and identify epidemic trends. Traditional techniques of serology and viral culture are limited by the lack of antibody response and delay in diagnosis. METHODS: We examined the clinical utility of indirect fluorescent antibody (IFA) testing in adult lung transplant patients with suspected RVI, compared with serology and culture. Nasopharyngeal and throat swabs (NT) were obtained to sample epithelial cells, followed by application of monoclonal antibody to respiratory syncytial virus, adenovirus, parainfluenza 1-3 and influenza A and B. The Bartels Respiratory Viral Detection kit was used with IFA results available within 24 hours. RESULTS: Nine of 18 patients tested positive for RVI with influenza A (n = 8) and influenza B (n = 1) detected. The sensitivity of IFA (67%) was higher than that of cell culture (45%). With intensive supportive therapy, infection was self-limiting in bronchiolitis obliterans syndrome (BOS) Grade 0-2 patients. However, patients with BOS Grade 3 manifested an acute exacerbation of airflow obstruction, which proved to be irreversible. CONCLUSIONS: Lung transplant patients with "flu-like" symptoms should proceed to IFA testing of NT swab specimens for early diagnosis. Samples collected within 7 days of symptom onset have high sensitivity as compared with serology and viral culture techniques.

Intravenous ribavirin is a safe and cost-effective treatment for respiratory syncytial virus infection after lung transplantation.

BACKGROUND: Community-acquired viral infections, such as respiratory syncytial virus (RSV), represent a risk factor for bronchiolitis obliterans syndrome (BOS), the major limiting factor for long-term survival after lung transplantation (LTx). RSV often presents with acute bronchiolitis and may be fatal in 10% to 20% of patients. Standard therapies for RSV include nebulized ribavirin with or without steroids, but are costly and inconvenient. We investigated the utility of intravenous (IV) ribavirin with steroids for the treatment of RSV infection after LTx. METHODS: RSV was identified in nasopharyngeal and throat swabs (NPS) using indirect fluorescent antibody (IFA) testing in 18 symptomatic patients, which was confirmed by viral culture in 14. Data were collected for the period between April 2002 and October 2004. The study included 10 men and 8 women, mean age 42 +/- 15 (range 18 to 63) years. Transplant procedures were 5 single LTx and 13 bilateral LTx. RSV diagnosis was made on Day 1,374 +/- 1,270 (range 61 to 4,598, median 935) post-operatively. Underlying diagnoses included cystic fibrosis (n = 9), emphysema (n = 7) and pulmonary fibrosis (n = 2). All 18 patients received intravenous (IV) ribavirin (33 mg/kg on Day 1 and 20 mg/kg/day thereafter in 3 divided doses) with oral prednisolone (1 mg/kg) until repeat NPS were negative for RSV on IFA. Median therapy was 8 days (6 to 15). RESULTS: The mortality rate was 0%. Mean FEV1 fell from 2.1 +/- 1.0 liter (0.7 to 3.7 liters) to 1.8 +/- 0.9 liter (0.5 to 3.6 liters) (p < 0.001), but recovered to 2.1 +/- 0.9 (0.7 to 3.7 liters) within 3 months and was maintained at follow-up of 521 +/- 328 days (141 to 1,023 days, median 302). Only 1 patient developed bronchiolitis obliterans syndrome (BOS). Complications included mild hemolytic anemia (blood hemoglobin fell from 122 +/- 22 [84 to 154] g/liter to 107 +/- 18 [75 to 138] g/liter, p = 0.02). Cost savings per 8-day course were $US15,913 when compared with nebulized therapy at 6 g/day (p < 0.001). CONCLUSIONS: This is the largest reported series of treated RSV cases after LTx and the first to show that therapy with IV ribavirin and oral corticosteroids is well tolerated and effective. Cost utility vs nebulized therapy has been established. Early diagnosis and management are essential to prevent airway epithelial injury and subsequent BOS.

Asthma exacerbations in children associated with rhinovirus but not human metapneumovirus infection.

Children with asthma were studied during the Southern hemisphere winter and summer of 2001-2002. Human rhinovirus (hRV) was significantly associated (P=.0001) with asthma exacerbations in winter and spring/summer, but not in intervening asymptomatic periods. Although hRV was also found in children with upper respiratory tract infection (URTI) who underwent sampling at the same time, it was present in significantly higher numbers of children with symptomatic asthma (P<.0001). Human metapneumovirus was also found in small numbers of children with URTI, but significantly less frequently in children with asthma.

New point of care test is highly specific but less sensitive for influenza virus A and B in children and adults.

The importance of rapid diagnosis of influenza has increased with the availability of neuraminidase inhibitors, which need to be commenced within 48 hr of symptom onset. Furthermore, the recent development of influenza-like clinical syndromes with novel aetiologies (severe acute respiratory syndrome, SARS) has increased the need for rapid and accurate near-patient diagnosis. A new, modified point of care (POC) diagnostic test (ZstatFlu) was assessed on 469 nasopharyngeal aspirates (NPAs) and 260 nose/throat swabs (TS) taken from children and adults. The test was specific (77-98%) for all specimen types for influenza virus A and B, depending upon incubation conditions. However, it was less sensitive, detecting 65-77% of specimens confirmed as positive on culture, direct immunofluorescence or PCR testing. A positive test is useful, for both directing initiation of therapy in the clinician's office, and making a positive diagnosis of influenza in patients with influenza-like clinical syndromes.