The Burden of Influenza-Associated Hospitalizations in Oman, January 2008-June 2013.

INTRODUCTION: Acute respiratory infections (ARI), including influenza, comprise a leading cause of morbidity and mortality worldwide. Influenza surveillance provides important information to inform policy on influenza control and vaccination. While the epidemiology of influenza has been well characterized in western countries, few data exist on influenza epidemiology in the Eastern Mediterranean Region. We describe the epidemiology of influenza virus in Oman. METHODS: Using syndromic case definitions and protocols, patients from four regional hospitals in Oman were enrolled in a descriptive prospective study to characterize the burden of severe acute respiratory infections (SARI) and influenza. Eligible patients provided demographic information as well as oropharyngeal (OP) and nasopharyngeal (NP) swabs. Specimens were tested for influenza A and influenza B; influenza A viruses were subtyped using RT-PCR. RESULTS: From January 2008 through June 2013, a total of 5,147 cases were enrolled and tested for influenza. Influenza strains were detected in 8% of cases for whom samples were available. Annual incidence rates ranged from 0.5 to 15.4 cases of influenza-associated SARI per 100,000 population. The median age of influenza patients was 6 years with children 0-2 years accounting for 34% of all influenza-associated hospitalizations. By contrast, the median age of non-influenza SARI cases was 1 year with children 0-2 years comprising 59% of SARI. Compared to non-influenza SARI cases, a greater proportion of influenza cases had pre-existing chronic conditions and underwent ventilation during hospitalization. CONCLUSIONS: Influenza virus is associated with a substantial proportion of SARI in Oman. Influenza in Oman approximately follows northern hemisphere seasonality, with major peaks in October to December and a lesser peak around April. The burden of influenza was greatest in children and the elderly. Future efforts should examine the burden of influenza in other potential risk groups such as pregnant women to inform interventions including targeted vaccination.

A hospital acquired outbreak of Bacillus cereus gastroenteritis, Oman.

OBJECTIVES: To investigate the course of a hospital acquired outbreak of Bacillus cereus gastroenteritis outbreak, and the interventions that were taken to prevent such an outbreak from occurring again. METHODS: On May 3-5 2008, 58 cases of gastroenteritis were reported among patients and their attendants in a referral hospital in Oman. All affected had eaten meals served by the hospital kitchen the previous day. An outbreak investigation team conducted active surveillance and interviewed people about symptoms and food consumed on the preceding day in the hospital. Food samples from the kitchen and faecal samples from the kitchen staff and those affected were cultured. An environmental audit of the kitchen was conducted. RESULTS: The majority of the 58 persons affected by the outbreak were adult females, predominantly attendants of patients. 90% had diarrhoea and 10% had vomiting, usually mild. All those affected were managed symptomatically except for two patient attendants who required intravenous rehydration. The meal exposure histories implicated at least one meal from the kitchen. Many violations of basic food hygiene standards were observed in the kitchen. Toxin producing B. cereus was isolated from faeces of 3/12 (25%) patients and 19/25 (76%) of food handlers, and 35/61 (57%) of food samples from the kitchen. CONCLUSION: This is the first report of a nosocomial outbreak of foodborne B. cereus infection from this region. The importance of appropriate epidemiological and microbiological investigation and public relations management is emphasized, in addition to the need for continuing training of food handlers and rigorous enforcement of food hygiene regulations.