Epidemiologic and virologic assessment of the 2009 influenza A (H1N1) pandemic on selected temperate countries in the Southern Hemisphere: Argentina, Australia, Chile, New Zealand and South Africa.

UNLABELLED: INTRODUCTION AND SETTING: Our analysis compares the most comprehensive epidemiologic and virologic surveillance data compiled to date for laboratory-confirmed H1N1pdm patients between 1 April 2009 - 31 January 2010 from five temperate countries in the Southern Hemisphere-Argentina, Australia, Chile, New Zealand, and South Africa. OBJECTIVE: We evaluate transmission dynamics, indicators of severity, and describe the co-circulation of H1N1pdm with seasonal influenza viruses. RESULTS: In the five countries, H1N1pdm became the predominant influenza strain within weeks of initial detection. South Africa was unique, first experiencing a seasonal H3N2 wave, followed by a distinct H1N1pdm wave. Compared with the 2007 and 2008 influenza seasons, the peak of influenza-like illness (ILI) activity in four of the five countries was 3-6 times higher with peak ILI consultation rates ranging from 35/1,000 consultations/week in Australia to 275/100,000 population/week in New Zealand. Transmission was similar in all countries with the reproductive rate ranging from 1.2-1.6. The median age of patients in all countries increased with increasing severity of disease, 4-14% of all hospitalized cases required critical care, and 26-68% of fatal patients were reported to have ≥1 chronic medical condition. Compared with seasonal influenza, there was a notable downward shift in age among severe cases with the highest population-based hospitalization rates among children <5 years old. National population-based mortality rates ranged from 0.8-1.5/100,000. CONCLUSIONS: The difficulty experienced in tracking the progress of the pandemic globally, estimating its severity early on, and comparing information across countries argues for improved routine surveillance and standardization of investigative approaches and data reporting methods.

Why New Zealand must rapidly halve its greenhouse gas emissions.

New Zealand must commit to substantial decreases in its greenhouse gas emissions, to avoid the worst impacts of climate change on human health, both here and internationally. We have the fourth highest per capita greenhouse gas emissions in the developed world. Based on the need to limit warming to 2 degrees C by 2100, our cumulative emissions, and our capability to mitigate, New Zealand should at least halve its greenhouse gas emissions by 2020 (i.e. a target of at least 40% less than 1990 levels). This target has a strong scientific basis, and if anything may be too lenient; reducing the risk of catastrophic climate change may require deeper cuts. Short-term economic costs of mitigation have been widely overstated in public debate. They must also be balanced by the far greater costs caused by inertia and the substantial health and social benefits that can be achieved by a low emissions society. Large emissions reductions are achievable if we mobilise New Zealand society and let technology follow the signal of a responsible target.

A school and community outbreak of tuberculosis in Palmerston North, New Zealand.

AIM: To describe a secondary school outbreak of tuberculosis in Palmerston North, New Zealand in 2006. METHODS: Case and contact management was conducted by MidCentral District Health Board according to national guidelines. RESULTS: The index (and source) case was a school student. Delayed diagnosis led to extensive transmission. Contact investigation detected fifteen secondary cases, from six of whom Mycobacterium tuberculosis organism was cultured which was identical to that found in the index case. Latent tuberculosis infection was diagnosed in 235 of 1828 contacts. Following logistic regression, risk of infection was significantly associated with age, exposure setting (household and school vs other settings) and duration of exposure. Large numbers of contacts were infected who had no known contact with the index case, thus indicating probable tertiary transmission from the 7 infectious secondary cases. The secondary healthcare cost of the outbreak was estimated at $279,481. Findings from school tuberculosis (TB) outbreaks since 1990 are summarised. CONCLUSION: This was the largest tuberculosis outbreak described in New Zealand and one of the largest school outbreaks reported in the published literature.