Effect of thunderstorms and airborne grass pollen on the incidence of acute asthma in England, 1990-94

Abstract

England was followed closely by a tenfold increase in attendance of patients at hospital Background -Thunderstorms and prior grass pollen counts were investigated as casualty departments due to acute asthma attacks. 2 3 Mechanisms have been proposed predictors of daily hospital admissions for asthma in England. This study was mo-whereby thunderstorms might cause acute asthma attacks. In the case of the June 1994 tivated by reports in the literature of spectacular asthma epidemics associated with epidemic, it was found that an exceptionally high grass pollen count had been recorded thunderstorms, particularly in the grass pollen season.in London two days previously. 3 It has been proposed that the humidity preceding a thunMethods -Asthma admissions for two age groups (0-14 years and 15 and over) were derstorm, or rainfall during a thunderstorm, might lead to rupture of pollen grains releasing measured using the Hospital Episodes System (HES) in the 14 regional health submicroscopic starch granules which are then broadcast by the rapid air movement associated authorities (RHAs) in England. Thunderstorms were measured daily in each with the thunderstorm.6 These fragments carry allergens such as Lol p IX 7 and were proposed RHA using densities of sferics (lightning flashes). Relative asthma excesses for as the cause of thunderstorm-associated asthma epidemics in Melbourne.4 moderate positive and exceptionally high sferic densities, with or without previous Clearly, not all thunderstorms are associated with asthma epidemics on the scale experienced high grass pollen counts, were measured using log linear autoregression -allowing in June 1994. Therefore, even if there is a causal link between thunderstorms and asthma, for weekly, seasonal, and longer term background variation -and pooled over there must be some other factors which interact with the thunderstorms that would have to be RHAs by calculating geometric means. Results -Relative risks from all RHAs taken into account in building any early warning system for asthma epidemics. These factors were pooled to form geometric means. Exceptional sferic densities were associated might be aeroallergens such as those from grass pollen. with a relative excess risk of around 25% in both age groups. Moderate sferic densitiesIn this report we quantify the rise in the (Thorax 1997;52:680-685) series for the two age groups show a markedly * Present address: Telford Institute of Environmental different seasonal pattern with the younger

A trans-disciplinary overview of case reports of thunderstorm-related asthma outbreaks and relapse

“…Of note, the authors measured pollen counts and, for the first time, thunderstorms using densities of sferics (lightning flashes). However, the data from NEWSON et al [33] do not support the possibility of predicting asthma outbreaks by using meteorological data and pollen counts. In their study, thunderstorms and high grass pollen levels preceded asthma epidemics more often than expected by chance.…”

“…Therefore, it is of interest to establish which risk factors may predict the occurrence of asthma outbreaks in such a way that early warning systems can be developed. With this approach, and using the same data set as above, NEWSON et al [33] identified 56 asthma epidemics defined as periods of exceptionally high asthma admission counts compared with predictions of a loglinear autoregressive model. Of note, the authors measured pollen counts and, for the first time, thunderstorms using densities of sferics (lightning flashes).…”

Thunderstorm-associated asthma in an inland town in south-eastern Australia. Who is at risk?

“…This is consistent with the findings of the current study in which 95% of thunderstorm cases were allergic to rye grass and a similar proportion reported prior hayfever symptoms. A severe thunderstorm together with a high grass pollen count prior to the thunderstorm was proposed as the cause of the London epidemic in 1994 [11]. and of the Melbourne epidemic [2,16,17].…”

“…Several meteorological features such as temperature, high humidity, rainfall, thunderstorm electric or lightening activity have been proposed as possible triggers for severe exacerbations of asthma following a thunderstorm [4,11], However, not all thunderstorms are associated with asthma exacerbations and not all asthma epidemics are preceded by thunderstorms [14].…”

Effects of weather types on hospital admissions for respiratory diseases in Castilla-La Mancha, Spain

“…The seasonal causes of the increases in asthma have been explained in terms of meteorological and pollutant variables. Regarding the meteorological variables, different authors have concluded that the symptoms may be related to the temperature prevailing during cold periods (Beer et al, 1991;Yuksel et al, 1996), changes in temperature (Crighton et al, 2001), relative humidity and rainfall (Celenza et al, 1996), fog (Kashiwabara et al, 2002), wind speed (Hashimoto et al, 2004), and changes in barometric pressure and storms (Sutherland and Hall, 1994;Newson et al, 1997).…”