Tuesday, November 8, 2011

Allergy Seasons in New Zealand

Calendar by Allergy New Zealand

New Zealand has mild temperatures, moderately high rainfall, and many hours of sunshine. The sunniest city is Tauranga, the wettest - Wellington, the driest Christchurch and the warmest city is Auckland. 
January and February are the warmest months, and July is the coldest month of the year. In summer, the average maximum temperature ranges between 20-30ºC and in winter between 10-15ºC.
New Zealand has relatively little air pollution and very strong UV rays during the summer months.
The country has a unique variety of native flora, mostly evergreen.  The introduced plants are the main source of pollen allergies. Rye is the most troublesome plant and the major cause of springtime hay fever. The pollen season starts about one month earlier at the top of the North Island than the bottom of the south Island. Pollen concentrations are slightly lower in coastal areas. Inland pastoral areas such as Hamilton and Palmerston North, can have relatively severe allergy seasons. In Auckland the main pollen season is between October and February, and  - unlike Europe and USA - is not well defined.
People of New Zealand, however, are not as affected by humidity and temperature changes as Western Europe is [1].  Similar to the rest of the world [2], prenatal and early life exposure to pollen can offer protection  against asthma, respiratory  allergy and eczema, but continued exposure may be required to maintain optimal protection [3].

1. Asher MI, Stewart AW, Mallol J, Montefort S, Lai CK, Aït-Khaled N, Odhiambo J; ISAAC Phase One Study Group. Which population level environmental factors are associated with asthma, rhinoconjunctivitis and eczema? Review of the ecological analyses of ISAAC Phase One. Respir Res. 2010 Jan 21;11:8.

2. Burr ML, Emberlin JC, Treu R, Cheng S, Pearce NE; ISAAC Phase One Study Group.
Pollen counts in relation to the prevalence of allergic rhinoconjunctivitis, asthma and atopic eczema in the International Study of Asthma and Allergies in Childhood (ISAAC). Clin Exp Allergy. 2003 Dec;33(12):1675-80.

3. Douwes J, Cheng S, Travier N, Cohet C, Niesink A, McKenzie J, Cunningham C, Le Gros G, von Mutius E, Pearce N. Farm exposure in utero may protect against asthma, hay fever and eczema. Eur Respir J. 2008 Sep;32(3):603-11. Epub 2008 Apr 30.