Clinical and epidemiological characteristics of the hospitalised patients due to pandemic H1N1 2009 viral infection: experience at Hutt Hospital, New Zealand

N Z Med J. 2010 Apr 9;123(1312):45-53.

Abstract

Aim: Pandemic H1N1 2009 virus (H1N1 2009) community transmission was first noted in New Zealand in the Wellington region. There is limited information of clinical and epidemiological characteristics of H1N1 2009 patients from USA and Mexico but no published reports available in New Zealand. We studied clinical and epidemiological features of patients with H1N1 2009 infection admitted to Hutt Valley Hospital.

Methods: We collected and analysed clinical and epidemiological information of all adult inpatient admitted to Hutt Hospital with confirmed H1N1 2009 infection over 5- week period from 17 June 2009 to 22 July 2009.

Results: There were 54 adult inpatient admissions with confirmed H1N1 2009 infection during the study period. Epidemic curve suggest rapid increase in number of cases during first 2 weeks with abrupt cessation of new cases by mid-July. The majority of the patients were female (74%) and belonged to Maori (38%) and Pacific (25%) races. Most of the patients were below 50 years of age (76%) but mean age of the cases increased weekly with progression of outbreak. The majority had comorbidities (78%) including asthma, obesity, and diabetes. 38% were smokers. 20% had diarrhoea and vomiting. 48% of the patient had multi-lobar infiltrates on chest X-ray. Nine patients received ICU/HDU (intensive care unit/high dependency unit) care and all of these patients had significant comorbidities. There were no deaths during this period.

Conclusions: H1N1 2009 infection predominantly affected young Maori and Pacific women with relative sparing of the elderly. Patient who received ICU/HDU care had significant comorbidities. This study provides a reliable account of clinical and epidemiological features of H1N1 2009 infection in a medium-size hospital in New Zealand.

MeSH terms

  • Adolescent
  • Adult
  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Asthma / epidemiology
  • Comorbidity
  • Diarrhea / virology
  • Disease Outbreaks*
  • Ethnicity
  • Female
  • Hospitalization*
  • Humans
  • Influenza A Virus, H1N1 Subtype*
  • Influenza, Human / epidemiology*
  • Intensive Care Units
  • Lung / diagnostic imaging
  • Male
  • Middle Aged
  • New Zealand / epidemiology
  • Pneumonia / epidemiology
  • Radiography
  • Sex Distribution
  • Vomiting / virology