Adult ; Comorbidity ; Humans ; Influenza A Virus, H1N1 Subtype ; isolation & purification ; Influenza, Human ; diagnosis ; drug therapy ; physiopathology ; Inpatients ; Male ; Pneumococcal Infections ; diagnosis ; drug therapy ; physiopathology ; Streptococcus pneumoniae ; isolation & purification ; Treatment Outcome

Absenteeism ; Emergency Service, Hospital ; Hospitals, General ; Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human ; epidemiology ; Personnel, Hospital ; Sentinel Surveillance ; Singapore ; epidemiology

INTRODUCTIONOutbreaks of acute respiratory illness occur commonly in long-term care facilities (LTCF), due to the close proximity of residents. Most influenza outbreak reports have been from temperate countries. This study reports an outbreak of influenza B among a highly immunised resident population in a welfare home in tropical Singapore, and discusses vaccine efficacy and the role of acute respiratory illness surveillance for outbreak prevention and control.

MATERIALS AND METHODSDuring the period from 16 to 21 March 2007, outbreak investigations and active case finding were carried out among residents and nursing staff at the welfare home. Interviews and medical notes review were conducted to obtain epidemiological and clinical data. Hospitalised patients were tested for respiratory pathogens. Further genetic studies were also carried out on positive respiratory samples.

RESULTSThe overall clinical attack rate was 9.4% (17/180) in residents and 6.7% (2/30) in staff. All infected residents and staff had received influenza immunisation. Fifteen residents were hospitalised, with 2 developing severe complications. Genetic sequencing revealed that the outbreak strain had an 8.2% amino acid difference from B/Malaysia/2506/2004, the 2006 southern hemisphere influenza vaccine strain, which the residents and staff had earlier received.

CONCLUSIONSA mismatch between the vaccine and circulating influenza virus strains can result in an outbreak in a highly immunised LTCF resident population. Active surveillance for acute respiratory illness in LTCFs could be implemented for rapid detection of antigenic drift. Enhanced infection control and other preventive measures can then be deployed in a timely manner to mitigate the effect of any outbreaks.

Adult ; Aged ; Disease Outbreaks ; prevention & control ; Female ; Humans ; Influenza B virus ; immunology ; Influenza Vaccines ; therapeutic use ; Influenza, Human ; epidemiology ; prevention & control ; virology ; Interviews as Topic ; Male ; Medical Audit ; Middle Aged ; Nursing Homes ; Singapore ; epidemiology ; Social Welfare ; Young Adult

INTRODUCTIONAlthough Singapore national guidelines recommend influenza vaccination for individuals with comorbidities, the vaccine uptake remains relatively low. This study examines the rates of influenza vaccine prescriptions in a clinic population, and patient, doctor and clinic factors that could affect the vaccine prescribing rates.

MATERIALS AND METHODSThis retrospective review utilised electronic medical records from HIV-infected patients seen in an infectious disease (ID) specialist clinic. Data from 40 randomly selected patients per physician were analysed for the outcome of influenza vaccine prescriptions from 1 January to 31 December 2007. All 7 consultants and the 6 ID registrars who had spent at least 4 months in the Department during 2007 were included. Data analysed included patient, physician, and clinic characteristics, and clinically relevant outcomes of admission within a year, and the length of hospital stay.

RESULTSOf the 461 HIV-infected patients analysed for this study, only 107 (23%) were prescribed influenza vaccine in 2007. Vaccine prescribing rates by individual physicians ranged from 0% to 77%. The outcome of vaccine prescribing was analysed by patient demographics (age >40 years, gender, race), physician characteristics (doctor grade, gender and training), and clinic volumes (number of patients per clinic session). Multivariate analysis demonstrated that patients with female doctors (OR 1.8, 95% CI, 1.1 to 3.0, P = 0.017), and doctors with overseas medical training (OR 11.6, 95% CI, 6.0 to 22.2, P <0.001) were significantly more likely to have influenza vaccine prescribed. On univariate analysis, patients were more likely to be admitted if they were male (OR 2.1, 95% CI, 1.0 to 5.1, P = 0.041), and over 40 years old (OR 2.1, 95% CI, 1.1 to 4.5, P = 0.024). Patients prescribed influenza vaccine showed a non-significant trend for protection against admission (OR 0.7, P = 0.288), and shorter length of stay (median 5 vs 9 days, P = 0.344).

CONCLUSIONInfluenza vaccine prescribing for HIV-infected outpatients in 2007 was only 23%, even in an ID specialist clinic. There was substantial variability in prescribing rates by individual physicians. Neither patient demographics nor patient volumes per clinic session had an impact on the prescribing rates, but significant predictors included physician gender and medical school training. Patients prescribed influenza vaccine had fewer admissions and shorter hospital lengths of stay, although these trends were non-significant.

Adult ; Drug Prescriptions ; statistics & numerical data ; Female ; HIV Infections ; complications ; Humans ; Influenza A virus ; immunology ; Influenza Vaccines ; pharmacology ; Influenza, Human ; prevention & control ; Male ; Prescription Drugs ; Retrospective Studies ; Singapore ; Vaccination ; trends

INTRODUCTIONHighly active antiretroviral therapy (HAART) has greatly changed the epidemiology of human immunodefi ciency virus (HIV) mortality. The aim of this study is to compare the causes of death and factors associated with early death in HIV-infected persons in the pre- and peri-highly active antiretroviral therapy (HAART) periods.

MATERIALS AND METHODSWe conducted a retrospective review of 483 HIV-infected persons who were diagnosed with HIV from 1985 to 2000, and had died within 5 years of the diagnosis. We examined the temporal change in the primary causes of death between those who were diagnosed in the pre-HAART (1985 to 1995) and peri-HAART (1996 to 2000) periods, and compared the demographic and clinical characteristics of the 2 groups.

RESULTSDuring the peri-HAART period, HIV encephalopathy, cryptococcal meningitis, and lymphoma were no longer the leading causes of death. Opportunistic infections remained important causes of death. Early deaths from the peri-HAART period were older (60 years and above) at diagnosis (Adj OR 7.50; 95% CI, 1.78 to 31.58), more likely to be divorced (Adj OR 5.05, 95% CI, 1.96 to 13.02) and tended to have a low baseline CD4 cell count of <50 cells/ uL (Adj OR 2.18, 95% CI, 1.14 to 4.16) , and were more likely to have received HAART (Adj OR 5.19; 95% CI, 2.22 to 12.12) than early deaths from the pre-HAART period.

CONCLUSIONIn the peri-HAART era, HIV-infected persons who died within 5 years of diagnosis were those who were older (≥60 years), divorced, or who presented with very late-stage disease (CD4 <50) at diagnosis. More targeted public health interventions, such as targeted public health messages and outreach to increase access to HIV testing and treatment should be developed for these subpopulations.

AIDS-Related Opportunistic Infections ; mortality ; Adult ; Anti-Retroviral Agents ; therapeutic use ; Antiretroviral Therapy, Highly Active ; CD4 Lymphocyte Count ; Cause of Death ; trends ; Confidence Intervals ; Female ; HIV Seropositivity ; drug therapy ; immunology ; mortality ; HIV-1 ; drug effects ; immunology ; Humans ; Male ; Medical Audit ; Middle Aged ; Mortality, Premature ; trends ; Odds Ratio ; Retrospective Studies ; Singapore ; epidemiology

INTRODUCTIONSince the fi rst imported case on 26 May 2009, pandemic (H1N1) 2009 has spread from travellers and has resulted in sustained community transmission. Singapore began with a strict containment policy where all suspected and confirmed cases of pandemic (H1N1) 2009 were admitted for testing. We describe here the clinical and laboratory characteristics of the fi rst 50 adult cases with confirmed pandemic (H1N1) 2009.

MATERIALS AND METHODSA review was conducted of medical notes of adult patients with confirmed pandemic (H1N1) 2009 by polymerase chain reaction assay from combined nasal and throat swabs admitted to the Communicable Disease Centre, Tan Tock Seng Hospital.

RESULTSFrom 26 May to 18 June 2009, 50 patients with a median age of 27 years old were admitted at a median of 3 days from illness onset. Half were male and all were travellers arriving in Singapore. Non-Singaporean citizens (38%) and other ethnic groups (40%) were over-represented. History of fever was reported in 90% and respiratory symptoms in 92%. Gastrointestinal symptoms were uncommon, present in 4% only. Temperatures on presentation of >or=38.0 degrees C, >or=37.8 degrees C and >or=37.5 degrees C were present in 48%, 56% and 76%, respectively. Only 46% of patients met the United States Centers for Disease Control and Prevention (US CDC) case definition of influenza-like illness (ILI). Clinical and laboratory findings were unremarkable for the majority. All cases were treated with oseltamivir and had uncomplicated recovery.

CONCLUSIONPandemic (H1N1) 2009 had mild clinical and laboratory findings in immunocompetent patients. Use of the US CDC ILI criteria alone would have detected less than half of confirmed cases.

Adult ; Communicable Diseases, Emerging ; epidemiology ; Disease Outbreaks ; Female ; Humans ; Influenza A Virus, H1N1 Subtype ; isolation & purification ; Influenza, Human ; diagnosis ; epidemiology ; Male ; Medical Audit ; Middle Aged ; Polymerase Chain Reaction ; Singapore ; epidemiology ; Young Adult