[Lifelong Mask Mandate].

INTRODUCTION: A 31-year-old farmer is being treated for suspected pneumonia. As the symptoms persist despite antibiotic treatment, the suspicion of hypersensitivity pneumonitis type Farmer´s lung arises after taking into account the patients occupational history. Information from various examination modalities and the clinical course confirm the suspected diagnosis. Thanks to the rapid diagnosis and the measures taken as a result, it was possible for the patient to remain in his profession.

Farmer's Lung Disease. A Review. / Revisión de la enfermedad del pulmón de granjero.

Farmer's lung disease (FLD) is a form of hypersensitivity pneumonitis (HP) caused by inhaling microorganisms from hay or grain stored in conditions of high humidity in the agricultural workplace. It is probably underdiagnosed, especially in northern Spain, where climatic conditions favor the development of this disease. According to previous studies, the most common antigens are usually thermophilic actinomycetes and fungi. The epidemiology of the disease is not well known, and is based on studies conducted by Central European and Asian groups. The clinical presentation may vary, differentiating the chronic (exposure to lower concentrations of the antigen over a longer period time) and the acute forms (after exposure to high concentrations of the antigen). In patients with respiratory symptoms and agricultural occupational exposure, radiological, lung function and/or anatomical pathology findings must be compatible with FLD, bronchoalveolar lavage must show lymphocytosis, and tests must find sensitivity to the antigen. The main treatment is avoidance of the antigen, so it is essential to educate patients on preventive measures. To date, no controlled studies have assessed the role of immunosuppressive therapy in this disease. Corticosteroid treatment has only been shown to accelerate resolution of the acute forms, but there is no evidence that it is effective in preventing disease progression in the long-term or reducing mortality.

Impact of agricultural practices on microbiology of hay, silage and flour on Finnish and French farms.

Exposure to microorganisms in farm environments may cause respiratory disorders, e.g. asthma, organic dust toxic syndrome and allergic alveolitis. By reducing microbiological deterioration of organic materials, some agricultural practices have a protective effect. Microbiological analyses were carried out on hay, silage and flour samples (n=107) from farms in Finland and France (n=23) that use different methods of haymaking. High concentrations of Absidia corymbifera were found in approximately 35 % of French hay samples and only 10 % of Finnish hay samples. Concentrations of Eurotium spp. were found in 20 % of hay samples from both regions. High concentrations of Wallemia sebi typified Finnish hay (38 %) more than French hay (8 %). Rhodotorula yeast was frequently and abundantly found in Finland, but never in France. The method used to make hay appeared to be the main factor affecting the microbiology of the hay. A. corymbifera and Eurotium spp. concentrations were smaller in low-density square bales than in others. In conclusion, our results emphasize the importance of good agricultural practice in the microbiological quality of fodder.

Evaluation of salting as a hay preservative against farmer's lung disease agents.

Salting is a traditional, empirical practice used commonly in dairy farming regions to prevent moulding and heating in hay. Our aim was to evaluate the effect of salting hay on the proliferation of microorganisms, particularly thermophilic actinomycetes and moulds involved in farmer's lung disease. Fifty-one pairs of salted and unsalted hay bales from 14 farms were produced during the haymaking season between March and July. Both the salted and the unsalted bales came from the same field, and were packed and stored under identical conditions. Sampling was performed by microbiological analysis including 6 culture media during the winter following salting (January-February). The use of salt did not significantly decrease the amount of Saccharopolyspora rectivirgula , the actinomycetes most commonly involved in farmer's lung disease, or that of Absidia corymbifera, Eurotium amstelodami and Wallemia sebi , three moulds responsible for farmer's lung disease in eastern France. Our results are important in that they can inform farmers and dispel the false sense of security induced by salting, which is reinforced by the misconception that palatable hay is healthy hay.

Occurrence of farmer's lung disease is relevant to meteorological conditions: a 20-year follow-up field survey analysis.

BACKGROUND: A field survey on farmer's lung disease (FLD) in a dairy farming community in the northernmost district of Japan has been in progress since 1978. METHODS: The correlation between the number of FLD occurrences year by year and dairy farming conditions and meteorological data were compared. RESULTS: Thirty-four FLD cases had occurred in a 20 years period. Average number of days below freezing during the harvest season the year prior to FLD occurrence were significantly smaller than other years (2.1 +/- 0.7 [SE] days, 4.6 +/- 0.7 days, P < 0.05, respectively). Average annual sum of the sunlight hours in the years before the years with FLD occurrence was significantly smaller than those without FLD occurrence (1457.1 +/- 114.0 hr, 1811.3 +/- 97.7 hr, P < 0.05, respectively) and was also significantly smaller for the sunlight hours during a harvest season (821.9 +/- 60.2 hr, 1023.2 +/- 52.7 hr, P < 0.05, respectively). CONCLUSIONS: Temperature and sunlight hours closely associated with the FLD occurrence.

Influence of buffered propionic acid on the development of micro-organisms in hay.

We tested the benefit of using buffered propionic acid (BPA) as a means of preventing farmer's lung disease (FLD). BPA, a new formulation of propionic acid, a hay preservative with no deleterious effect on farm machinery or cattle, reduces the development of micro-organisms in hay. Twenty pairs of round bales were analysed for concentration of micro-organisms measured in the winter following hay treatment. Each pair included one untreated bale and one bale treated with BPA during haymaking. Our results showed the following decreases in concentration in treated bales: total fungal species, 40% (P < 0.05); Eurotium amstelodami (the main species found), 65% (P < 0.01); and thermophilic actinomycetes, 60% (not significant), respectively. We conclude that BPA could be used to prevent FLD.

[Bacterial endotoxins produced by Alcaligenes faecalis and Erwinia herbicola as potential occupational hazards for agricultural workers]. / Endotoksyny bakteryjne Alcaligenes faecalis i Erwinia herbicola czynnikami narazenia zawodowego w rolnictwie.

Laboratory animals (guinea pigs and rabbits) were exposed to the inhalation of aerosolized endotoxins derived from the cell mass of Alcaligenes faecalis and Erwinia herbicola, the Gram-negative bacteria commonly occurring in organic dusts. Single 1 hour-lasting exposure caused the significant increase in the number of free lung cell, mostly lymphocytes, compared to the control group exposed to saline (P < 0.001). Prolonged exposure to tested endotoxins (Fifteen 1 hour-lasting exposures every second day) caused both specific and non specific immunological changes: enhanced inhibition of leukocyte migration production of precipitins, and activation of alveolar macrophages, wes assessed by greater antibacterial activity and increased interleukin I (IL-I) production. The results indicate that the endotoxins of examined bacteria represent a potential risk of inflammatory lung reaction and respiratory disease for agricultural workers inhaling organic dusts contaminated with these organisms.

[Dust exposure, dust-induced lung diseases and respiratory protective measures in agriculture]. / Staubbelastung, staubbedingte Lungenkrankheiten und Atemschutzmassnahmen in der Landwirtschaft.

Epidemiologic studies indicate a high prevalence of respiratory diseases among the farming population. Many of these diseases are responsible for disability and death and there is a considerable impact on the economy and health cost expenditure. Respirable organic dust plays a major pathogenetic role. Part I of this review discusses the diseases and syndromes caused by organic dust: organic dust toxic syndrome; chronic bronchitis and chronic obstructive pulmonary disease; asthma; and hypersensitivity pneumonitis. Part II describes preventive measures for dust control. Besides technical aspects in the process of agriculture production, special emphasis is placed on personal protective equipment systems (face-masks and air-purifying respirators). Applications, advantages and disadvantages of these systems are discussed and critically compared.

Two-year follow up on the protective value of dust masks against farmer's lung disease.

Some advocate moving away from the farm environment for farmers affected with farmer's lung disease (FLD), but most affected farmers still live on farms. In this study, we evaluated the practicality of dust masks and their effectiveness in prevention of FLD. The dust masks we chose were practically used and no new severe episodes of FLD developed in 20 of 21 farmers with FLD using the masks during a 2-year period. When the farmers took off the dust masks in a farming environmental provocation test, statistically significant reductions in FVC (mean 3.43 to 3.351, p < 0.01), DLco (mean 19.6 to 18.2 ml/torr/min, p < 0.01), and DL/VA (mean 5.1 to 4.8 (x10(-3)) 1/torr/min, p < 0.01) were observed several hours after exposure. These findings suggest that the dust masks were used practically during routine dairy farming and were effective in protection against FLD.

[Health problems among persons exposed to grain dust]. / Helbredsgener hos personer udsat for kornstøv.

This review describes health problems in persons primarily exposed to grain dust. The main epidemiological investigations from the nineteen seventies and eighties are reviewed. The commonest complaints were mucus membrane irritation. In the majority of investigations, an excess incidence of chronic bronchitis was encountered and it cannot be disproved that asthma developed in a number of the employees. Influenza-like symptoms compatible with the organic dust syndrome have been described in several investigations from silos but allergic alveolitis has not been described in this branch. The latter condition has been encountered in farm workers working with mouldy grain. With dust concentrations of about the Danish threshold limit value, many health problems still occur. The following prophylactic measures are recommended: Effective drying of corn before storage, effective ventilation and cleaning and covering of dusty working procedures. Epidemiological investigations are proposed in the Danish raw material sector to illustrate health problems related to grain dust. These investigations should be combined with qualitative and quantitative occupational hygienic measurements of dust.

[Mushroom growers' lung; clinical diagnosis and treatment]. / Champignonkwekerslong; klinische diagnostiek en behandeling.

The objective of this study was to give a description of the clinical picture, diagnosis and treatment in 19 patients with mushroom grower's lung. Of these patients, six worked at mushroom compost manufacturing, seven were traced by means of a nationwide enquiry among mushroom growers and six were referred by GPs. The following factors were measured after provocation at the worksite: pulmonary function, blood gas values, leukocyte count and body temperature. On the day of the provocation and on a control day chest X-rays were made. The most frequent complaints were dyspnoea and fever (in 15 and 13 patients, respectively). Serological tests in 16 of the 19 patients revealed antibodies against various fungi that occur in locations where mushroom compost is handled. Six to 12 hours after the provocation, all patients showed a rise of the mean body temperature from 37.1 to 38.4 degrees C; the mean leukocyte count rose from 7.7 to 17.0 X 10(9)/l. Lung function studies revealed restrictive disorders: the mean VC fell from 5.15 to 4.50 l, the TLC from 6.80 to 6.18 l. The differences, tested with Wilcoxon's two-sample test were significant (p less than 0.001). Roentgenological abnormalities were seen in two patients (reticular lung image). Treatment consisted of preventive measures, such as improved air conditioning at the worksite, wearing masks, wetting the compost to keep it from flying about, and supplying pretreated compost requiring no personal preparation.

Feeding and bedding materials as sources of microbial exposure on dairy farms.

Hay, grain, silage, and bedding are the sources of mold dust in agriculture. The aim of the present study was to evaluate the effect of different farming methods on exposure to airborne microbes. The study material comprised 50 silage, 54 hay, 47 grain, and 70 bedding samples taken on 18 farms in the beginning, middle, and end of the indoor feeding season. The modified wind-tunnel technique and six-stage impactors were used to determine the number of mesophilic bacteria, xerophilic fungi, mesophilic fungi, thermotolerant fungi, and thermophilic actinomycetes liberated from each material. Baled hay and straw liberated the largest amounts of microbes. Hay, except when dried in storage, liberated great numbers of fungal spores. The proportion of respirable airborne microbe-bearing particles was greatest in the highest concentrations. Theoretically, choosing the best possible alternative work methods could diminish exposure to microbes to one-tenth of the present level.

Utilization of masks by Hutterite farmers.

Respiratory symptomatology and pulmonary function tests were evaluated among 199 male Hutterites who utilized masks during farming and 159 Hutterites who did not use masks. Anthropometric and pulmonary function tests were comparable between the two groups. Symptomatology, including cough, phlegm, and wheezing were more prevalent among mask wearers compared to non-mask wearers. The prevalence of hayfever (p less than 0.02) and asthma (p less than 0.001) was greater among mask wearers vs non-mask wearers. Although the types and percent of individuals from each group raising crops and livestock were comparable, breathlessness, wheeze and fever were more common among the mask wearers. Thus farmers who suffered a higher incidence of symptoms as a consequence of farming are more likely to use masks.

An epidemiological study on farmer's lung among hay grinders in Dafeng County.

This article reports on an epidemiological survey of the presence of farmer's lung among 1054 farmers who grind moldy hay. The prevalence was 8.3-11.4%. The main pathogen was Thermoactinomyces vulgaris. The factors which influenced farmer's lung were the moldy state of the hay and the dust concentration. The epidemiological features of farmer's lung are analyzed and discussed and certain preventive measures are suggested.

Characteristics of farmers who have obtained personal dust respirators.

A postal survey was used to investigate the characteristics of farmers who have acquired dust respirators. In 1979 about a quarter of the farmers were using dust respirators, men more often than women. The more vocational training the farmer had and the larger the area of land under cultivation the more likely he was to own a dust respirator. Grain producers had purchased the protective devices more frequently than other farmers had. Farmers who participated in the occupational health intervention during 1980-82 had acquired dust respirators considerably more often than those in the control group. In the intervention group men under 30 years had most frequently purchased the dust respirators. Participation in the intervention influenced the acquisition of dust respirators more than did occurrence of symptoms of chronic bronchitis or farmer's lung.

Protective value of powered dust respirator helmet for farmers with farmer's lung.

Seventeen victims of farmer's lung were monitored during two indoor feeding seasons for cattle. The victims, who had all recovered from the acute phase of the disease before entering the experiment, used powered helmets for respiratory protection (Air-Stream) equipped with Type P2 filters. Filters were changed once a week. The lung function of each subject was investigated at the beginning and towards the end of the indoor feeding season. Each subject kept a diary about the use of dust respirators, changing of filters, inconvenience related to the use of respirators, and symptoms experienced during the follow-up. None of the subjects reported symptoms they related to farmer's lung, and mean values for the lung function parameters (PEF, FEV1, FVC, DLCO, and KCO) did not decrease during the two follow-up periods. In contrast, mean DLCO and KCO increased slightly. At the very end of the both indoor feeding seasons, after the actual follow-up periods, one subject developed mild recurrences of the disease without deterioration detectable by radiology. The patient asserted that he had used the protective helmet properly. The results indicate that powered respirator helmets have protective value in farmer's lung and are appropriate for long-term use. A possibility remains, however, that the disease may recur in highly sensitized individuals, despite the use of efficient protective devices. Other measures for preventing or decreasing mould exposure are equally important.