C4 BIOLOGICAL FACTORS
C4.1 MONITORING OF OCCURENCE OF AETIOLOGICAL AGENTS IN TICKS
In 2009 the monitoring of updated occurrence of the aetiological agents of Lyme borreliosis and meningoencephalitis on selected localities on the territory of the Capital City of Prague continued. It was targeted on the monitoring of activities of natural focuses of the infection under conditions of the Capital City.
Climate conditions affected the biological development of ticks, especially in summer months, when varying warmer weather prevailed. Ticks of all development stadiums were examined. The percentage of ticks infected with the aetiological agent of Lyme borreliosis was on average 10.1% in 2009. The highest positive proportion was found on localities of Prague 9 - Satalice Game Preserve (20%) and Olšany Cemetery (18.2%). Any presence of the virus of meningoencephalitis was not proven in 2009.
Nevertheless, everybody must care for prevention (suitable clothing, using repellents, timely removal of the tick, including disinfection of the attacked place, vaccination) when visiting Prague’s natural areas and not only on the aforementioned localities.
Detailed information is available at web pages of the Hygiene Station of the Capital City of Prague (www.hygpraha.cz, section professional information/epidemiology).
Fig. C4.1.1 Average occurrence of Lyme borreliosis aetiological agent in ticks, Prague, 2003–2009
C4.2 AEROBIOLOGICAL MONITORING OF AIR IN PRAGUE
The pollen airborne occurrence of various plant species may affect the level of troubles of an allergic person. The monitoring of the occurrence of pollen of various plant species, data evaluating, and predicting in the course of a pollen season has been carried out in Europe Since the 1960s. Czechoslovakia joined the network of the European Pollen Information Service in 1992. In 2009 there were in total ten monitoring stations of the Pollen Information Service (www.pylovasluzba.cz) operated on the territory of the Czech Republic. The Prague Station is located on the premises of the National Institute of Public Health in Šrobárova Street.
In Prague and generally in the Czech Republic the most important allergens in the spring season (dominated by pollen of tree species) are pollen grains of birch (Betula), in the broader sense of the whole family of Betulaceae. In summer time the unambiguously most important airborne allergens are grass species (Poaceae). Concentration of mould spores usually increases in important way in this period, too. This applies most significantly to families of Cladosporium and Alternaria. The dominance of weed, mostly mugwort (Artemisia), pollen is typical for the autumn period. Pollen grains of ragweed (Ambrosia) have been regularly occurring in the spectrum of aeroallergens found in Prague at the end of summer and brink of autumn. With respect to the explosive spreading of ragweed throughout Europe observed during the recent years this allergen occurrence must be carefully monitored and preventive measures implementation to eradicate ragweed from the Prague region must be promptly started. In August, a peak concentration of mould spores usually occurs being an order of magnitude higher than concentration of all other pollen allergens in this period.
The pollen season 2009 started at about one moth later than in the previous year – at the beginning of March. Its development and course are depicted in the graph below.
Fig. C4.2.1 The concentration of ragweed (Ambrosia) pollen in air, Prague, 1993–2009
Fig. C4.2.2 Concentrations of pollen allergens in air, Prague, 2009