2009 flu pandemic in New Zealand

2009 Flu pandemic in New Zealand

500+ Confirmed cases   50+ Confirmed cases   5-49 Confirmed cases   1-4 Confirmed cases
Deaths   Confirmed cases   Unconfirmed or suspected cases Influenza A H1N1 2009 pandemic in New Zealand
Disease	H1N1 Influenza 09 (Human Swine Influenza)
Virus strain	H1N1
Arrival date	25 April 2009
Origin	Thought to be Central Mexico
Deaths	19[1]
Confirmed cases	3,175[1]
Suspected cases‡	n/a
‡ Suspected cases have not been confirmed as being due to this strain of influenza by laboratory tests, although some other strains may have been ruled out.

In 2009 New Zealand had 3,175 cases and 19 deaths due to Swine influenza.^[1]

Outbreak history

On 25 April 2009 ten students from Rangitoto College, a secondary school in North Shore City, Auckland, exhibited influenza symptoms on returning from a three-week language trip to Mexico. All 22 students and three accompanying teachers from the trip and those in close contact with them were placed in voluntary home isolation and treated with oseltamivir. The ten students tested positive for an influenza A virus,^[2][3] with three of them later testing positive for swine flu.^[4] The symptoms were reportedly mild and all affected individuals have since recovered.^[5]

As of 30 May, New Zealand has had 9 laboratory confirmed cases and 10 probable cases. All have since recovered. There has been no substantive change to these figures since 15 May. New Zealand continues to identify isolate and treat suspected cases. There are currently 30 suspected cases and 23 people are in isolation being treated with Tamiflu.^[6] Confirmed cases have tested positive for the Mexican swine flu strain of influenza type A. Probable cases have tested positive for influenza type A after possible recent exposure to the Mexican strain. Suspected cases have flu symptoms after possible recent exposure to the Mexican strain. On 6 June a one-year-old boy from Manukau City was diagnosed with swine flu and several other people who had been exposed to him had gone into isolation.^[7]

On 8 June, the Ministry of Health confirmed three further cases of novel Influenza A(H1N1); bringing the national total to 17. One of the new cases is the son of a Canterbury man who recently flew into New Zealand on Air NZ flight NZ5. The other two new cases came from international flights from Los Angeles (NZ5) and Melbourne (NZ124). These people have been isolated and are being treated with Tamiflu. Health officials are in the process of contacted those who may have had contact with those confirmed of having Influenza A(H1N1).^[8] The following day, (9 June), the Ministry of Health reported two further cases. Both of these new cases travelled to New Zealand from Los Angeles on 31 May, and are currently in isolation with their close contacts. Concern has also be raised after 19 people (16 students, two teachers and one parent) from Gisborne Boys High School returned to New Zealand on 9 June, and five students began experiencing flu-like symptoms. ItA(H1N1)^[9] It was confirmed on 11 June that swabs taken from the students returned negative for novel Influenza.^[10]

As of 17 June, there was a cumulative total of 127 confirmed cases of novel H1N1 influenza in NZ.^[11] Some of these represent person to person transfers without a link to a person who had travelled recently meaning New Zealand has experienced a community level outbreak.

As of 29 June, there are 523 confirmed cases. The Ministry of Health changed plan from 'Containment' to 'Care in the Community'. There is 1 critical case in Hawkes Bay. The patient is said to have pre-existing medical conditions, but the doctors have put her condition down to Swine Flu.^[12]

As of 7 July, there are 1195 confirmed cases. The Ministry of Health changed plan from 'Containment' to 'Care in the Community'. There are 12 critical cases in Nationwide and 53 people have been hospitalised due to the flu.^[13]

According to a three months study coordinated by the Australian and New Zealand Intensive Care Research Centre that was published in the New England Journal of Medicine, up to 20 per cent of intensive care unit(ICU) beds overall were occupied by swine flu patients at the height of the pandemic in July. In New Zealand hospitals, about 25 per cent of all ICU activity was pandemic related and about 12 per cent of patients hospitalised with swine flu were admitted to ICU. The surge of patients with H1N1 influenza placed substantial strain on staff and resources, hospitals were stretched to the very limit of resources and were at the point where possible alternatives had to be considered. Unlike seasonal influenza strains, which tend to hit elderly people and those of severe underlying health problems more heavily, many of those who became critically ill with the swine flu were babies and middle-aged people, pregnant women, the obese, Pacific Islanders, Maori and Aboriginal patients. Rates of severe illness among Pacific people were seven times higher than the average, while those of Maori were twice as high. Overall, about one-third of patients who was admitted to an ICU because of swine flu had no underlying health problem. The first batch of swine flu vaccine arrived in the country in September. Currently only frontline health workers were in line to get the vaccine, but the Health Ministry is considering on widening access to include other "at risk" groups.^[14]

On 21 October, the Ministry of Health announced that the total number of death attributed to swine flu is 19 following a coroner's investigation of the 21 September death of a 35-year-old woman, with underlying medical conditions, in Waikato. The ministry expected the number to rise as the coroner completes investigations into a number of influenza-related deaths occurred over the last few months. Some students among a group visiting from Japan developed influenza in Christchurch in mid-October. Four were tested positive for influenza H1N1, and a number of others had influenza like symptoms. The ministry said it appeared that their illness originated in Japan. The group left New Zealand following treatment.^[1][15]

Impact

The impact in New Zealand is being monitored by health authorities and has resulted in school closures throughout the country. There have been multiple instances of community transmission, and threats to close the nation's borders.^[16]

Seasonal flu

New Zealand had about 48,000 influenza cases in the 2008 flu season – 42% of which were type A – and approximately 100 deaths a year directly attributed to influenza viruses.^[17]

Preparation

New Zealand has had a well-developed Influenza Pandemic action plan since 2006.^[18] Following this plan New Zealand immediately upgraded its influenza pandemic alert status to code yellow.^[19] The national stockpile of 1.4 million doses of oseltamivir was released to regional health authorities. The initial response as specified in the Pandemic Action Plan is a policy of border control and cluster control via voluntary quarantine and treatment of contacts with oseltamivir.

See also

• Health care in New Zealand

References

External links

• Ministry of Health - Influenza A (H1N1) Swine Flu page
• fluinfo.org.nz - a website operated by the Canterbury District Health Board