(Levetin, 1995)Fungi are eukaryotic organisms that belong to kingdom distant from plants and animals. Fungi include inconspicuous yeasts, moulds and mildews, as well as large mushrooms, puffballs and bracket fungi. Structurally fungi exist in single cells such as yeasts or thread like hyphae. Fungi normally reproduce through the formation of spores that may result from sexual and asexual reproduction. Sexual spores are result of genetic recombination and follow karyogamy where as asexual spores result from mitosis. Spores contain one to many cells and differ greatly in size, shape, color, and method of formation. Spores may be formed from the fragmentation of undifferentiated hyphae elements or highly specialized hyphal branches that may be contained within sporocraps or fruiting bodies. Mushrooms,  puffballs.

Brackets and morels are well known example these specialized sporocraps. Fungal spores germinate to produce hyphae, which grow and branch within the substrate, typically producing a colony that eventually forms a new generation of spores. Exposure to spores can cause human disease through well defined mechanism. Concerns about spores exposure and its effect are so common that all healthcare providers particularly allergists and immunologists have frequently faced issues regarding these real and asserted spore related illness.  The types of fungi and their abundance in an area depend on the availability of nutrients, water and temperature. We are aware that airborne pollen has well known and well defined seasons, fungal spores can be present virtually year round in many areas of the world. Atmospheric prevalence patterns of the dry air spora, especially those of Rhizopus , Alternaria and Cladosporium are very well known. Rhizopus is genus of moulds that includes cosmolitian filamentous fungi found in soil, decaying fruits, vegetables, animal faeces and old bread.  Rhizopus affects our body by attacking the immune system of our body and causing allergies to your body.Cladosporium is the most abundant genus identified from atmospheric sampling. Although spores can be present year
round but the highest overall concentrations often occur in summer and early fall in temperature areas. The fungi are well known allergen sources Fungus exposure is most commonly associated with hay fever and asthma but also has been implicated in hypersensitivity pneumonitis.(Wilkins,2005)

Alternaria is another class of spore forming fungi found in air and soil they are also common allergens in humans they usually cause hay fever or hypersensitivity reactions that lead to asthama. Many fungal spores contain allergens that may cause one or more of the allergic disease. Note that unlike infectious agents spores may not have to be viable to retain allergenic properties. Hence it is important to know the concentration and composition of the total air spore including non culturable spores and allergen containing fragments, which require immunochemical methods for detection.

(Halleren 1991)Pollen counts Daily count for moulds Alternaria spp, grass tree and weed and herb pollen were monitored. Airborne pollen grains and moulds should be trapped on Melinex tape coated with adhesive mounted on a rotating drum driven by mechanical clock onto which air should be drawn at 10 liters per minute, by the means of an electrically powered vacuum pump. The 24 hours portions of exposed tape should be mounted on individual  labeled and dated glass slides stained with 2  Saffranin in glycerol jelly and counted by scanning three 48 mm runs then by using high power light microscopy and multiplying the total number by53 to enable the count to be expressed in grains per cubic meter

Pollen identification Reference slides of pollen should be collected from identified plants should be prepared over several years and validate by number of botanists enabling many air borne
pollen to be identified and classified into family or genus and some to species level. Reference slides of pollen from named native flora growing in Mount Annan Botanic gardens

(Bass and Morgan 1997)Sydney is the largest city in Australia. There has been no published pollen calendar for Sydney virons since 1941. The present quantitative study has been monitored using Burkard 7 day volumetric spore trap since August 1992.The site has been choosen because of the high prevalence of asthama and the high rate of childhood asthama. The spore trap is sited on the boundary of farm lands to the south developed commercial and housing areas to the north east and north Sydney the prevailing winds are mainly north easterly to south easterly between November and march and south westerly between April and October.the climate of Sydney is subtropical with the mean daily temperature ranging from 22.9 in janury to 12.6 in July. A seasonal pattern of Alternaria sporulation, similar to that of southwest Sydney was observed in Melbourne. According to the statistical analysis Alternaria spore counts in south west Sydney are significantly higher and last longer. In Sidney highest is in the month of November. In south western Sidney where most rain falls during spring and summer between September and January. The influence of sea breeze increases humidity which reduces Alternaria sporulation.

The spore trap in south western Sydney is 30 kilometers from the coast with little sea breeze and on the edge of farming land.(Bass and Morgan,1997) It is likely that not only lower humidity but also local farming practices would assist sporulation. It is therefore necessary when comparing spore counts in different location to be aware of local topography. The data between January 1993 and December 1995 presented in this paper suggests that there is an association between Alternaria spore release and grass pollen release, both of which peak in November. In 1994 when rain fall in Campbell town was low so the total grass pollen count was also low, the total Alternaria count was high .In contrast in 1995 when rainfall increased the total pollen count increased but the Alternaria spore count decreased. The relationship of both grass pollen and Alternaria spore release is dependent upon humidity and rainfall with hot dry days promoting both spore and pollen release. Alternaria is dry where sporulation decreases in rain and increases in dry whether. In the Tucson study peak deposition of Alternaria spores was associated with increasing temperature and decreasing relative humidity. There is a distinct seasonal pattern with Alternaria spore numbers being low in winter and increase in in late spring and early summer, with biomodal peak in November- December, the season of highest rainfall in Sydney and a lower bimodal peak in February   March. The increases could be related to the maturing and sense cense of tree foliage as well as grass and to some extent local crops. Statistical seasonal pattern have demonstrated a negative correlation with rainfall and highly significant correlation with average temperature. Hence it was found that there is a linear relationship between cumulative spore counts and cumulative temperature. Whereas Alternaria spore counts using Burked spore trap sited in a cotton field averaged a background level of 70 spores m3 in April one month before harvesting commenced. The study demonstrated that clouds of Alternaria spores travel some distance and that communities living near cotton fields would be exposed to continue levels of Alternaria round the year. As there is a wide variation of pollen numbers from season to season and variation between start and finish of pollination of many flowering plants only pollen calendar is useful in showing a seasonal pattern. Australia being the driest island continent in the world this variability of pollination is linked to rainfall which proceeds the growing period. This analysis showed that pollen counts totally depends on climatic

A large proportion of the population in Sydney lives 30 kilometers inland from coast. This calendar shows seasonal pattern of the flowering tree grass and weed pollen is appropriate to the environment and will help in the diagnosis and treatment of seasonal rhinoconjunctivitis from pollen  asthama .As Alternaria is a risk factor for asthama and a risk factor for sudden respiratory arrest, Alternaria spore counts should be performed routinely at the same time as pollen monitoring.


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