Antimicrobial Resistance of Staphylococcus aureus Strains Acquired by Pig Farmers from Pigs

Carriage of animal-associated methicillin-resistant Staphylococcus aureus (MRSA) clonal complex 398 (CC398) is common among pig farmers. This study was conducted (i) to investigate whether pig farmers are colonized with pig-specific S. aureus genotypes other than CC398 and (ii) to survey antimicrobial resistance of S. aureus isolates from pigs and pig farmers. Forty-eight S. aureus isolates from pig farmers and veterinarians and 130 isolates from pigs collected in Western Switzerland were genotyped by spa typing and amplified fragment length polymorphism (AFLP). Antimicrobial resistance profiles were determined for representative sample of the isolates. The data obtained earlier on healthy S. aureus carriers without exposure to agriculture were used for comparison. The genotype composition of S. aureus isolates from pig farmers and veterinarians was similar to isolates from pigs with predominant AFLP clusters CC398, CC9, and CC49. The resistance to tetracycline and macrolides (clarithromycin) was common among the isolates from farmers and veterinarians (52 and 21%, respectively) and similar to resistance levels in isolates from pigs (39 and 23%, respectively). This was in contrast to isolates from persons without contact with agriculture, where no (0/128) isolates were resistant to tetracycline and 3% of the isolates were resistant to clarithromycin. MRSA CC398 was isolated from pigs (n = 11) and pig farmers (n = 5). These data imply that zoonotic transmission of multidrug-resistant S. aureus from pigs to farmers is frequent, and well-known MRSA transmission merely represents the tip of the iceberg for this phenomenon. We speculate that the relatively low frequency of MRSA isolation is related to lower antimicrobial use in Switzerland compared to, for example, the Netherlands.     

Secondary Staphylococcus aureus intramammary colonization is reduced by non-aureus staphylococci exoproducts

Non-aureus staphylococci (NAS) and Staphylococcus aureus are pathogens that cause bovine mastitis, a costly disease for dairy farmers, however; many NAS are considered part of the normal udder microbiota. It has been suggested that through a mechanism that remains to be elucidated, NAS intramammary colonization can prevent subsequent infection with other bacterial pathogens. This study shows that in a murine mastitis model, secondary Staph. aureus intramammary colonization is reduced by exoproducts from Staph. chromogenes and Staph. simulans, both NAS, while Streptococcus spp. exoproducts have much less ability to affect the course of the infection caused by S. aureus.     

Impact of environmental changes on farmed seaweed and farmers: the case of Songo Songo Island,Tanzania

Tanzania, like many other countries where eucheumatoid seaweeds are farmed, is experiencing die-off of Kappaphycus alvarezii. Farming is failing in many cultivation sites in shallow intertidal areas where it used to grow well. Production has fallen dramatically, and in some areas, hardly any seaweed is produced any longer. This study was carried out in Songo Songo Island, southern Tanzania, one of the most affected areas, during February–May 2009. Water temperature averaged 35.7?±?2.4 °C, higher than what had been observed in seaweed farms in other areas in Tanzania. Salinity was normal seawater at 34.7?±?0.5 ppt. In the abandoned farming sites, signs of ice-ice, epiphytic Neosiphonia and “dark spots” were observed on the seaweed. Fouling was also observed. Seaweed production decreased from 423.9 t worth US$82,000 in 2003 to 26 t in 2008 worth only US$4,500, and 28 t in 2012 worth US$4,300. Number of farmers was highest (809) during the production peak in 2003 then decreased to 320 in 2008. The number of fishing vessels decreased with an increase in number of farmers and seaweed production and increased when the number of farmers and seaweed production fell. Thus, high-surface water temperatures coupled with fouling, epiphytism, and ice-ice disease signs have caused dramatic decrease in seaweed production in Songo Songo. The onetime lucrative seaweed farming activity in Songo Songo Island of Tanzania has been reduced to almost standstill.     

Evaluating the efficacy of biological control of three exotic homopteran pests in tropical Africa

Techniques for evaluating biological control of cassava mealybug (Phenacoccus manihoti Matile-Ferrero), mango mealybug (Rastrococcus invadens Williams), and spiralling whitefly (Aleurodicus dispersus Russell) are described. In each case, two exotic hymenopterous parasitoids were introduced. Alone or together, they brought the pests under control, while indigenous and exotic coccinellids played a minor role. Control was achieved in large areas where the exotic parasitoid(s) had been present for more than 2–4 years. The impact was documented by (1) exclusion experiments; (2) long-term population dynamics studies; (3) laboratory and field experiments contributing to simulation models; and, most importantly, (4) quantitative results from large-scale surveys evaluated by multivariate analyses. In many countries, the main introduced parasitoid proved to be the most important factor contributing to the decline of the pest populations, recovery of plant growth and yields. Non-target species were only affected through the reduction in their food sources. The impact was scale-neutral, benefitting subsistence farmers and commercial farmers alike. The population reduction remained stable (in the order of ten times over outbreak levels). In economic terms, excluding ecological and health benefits, both theP. manihoti andR. invadens projects returned benefits to African farmers that amounted to a multiple of the research and implementation costs paid for by development agencies. Sound evaluation of the efficiency of biological control is considered to have been one of the pillars for the ultimate success of these projects.     

Potential of the neem tree (Azadirachta indica) for pest control and rural development

The neem tree (Azadirachta indica) contains promising pest-control substances found effective against many economically important pests. These materials are easy to process by village-level industries and easy to use by limited-resource farmers, thereby offering potential for crop protection and off-farm income generation. The tree’s numerous pharmacological and other complementary uses make it doubly attractive for incorporation in large-scale rural development efforts.     

Carotenoid inhibitors reduce strigolactone production and Striga hermonthica infection in rice

The strigolactones are internal and rhizosphere signalling molecules in plants that are biosynthesised through carotenoid cleavage. They are secreted by host roots into the rhizosphere where they signal host-presence to the symbiotic arbuscular mycrorrhizal (AM) fungi and the parasitic plants of the Orobanche, Phelipanche and Striga genera. The seeds of these parasitic plants germinate after perceiving these signalling molecules. After attachment to the host root, the parasite negatively affects the host plant by withdrawing water, nutrients and assimilates through a direct connection with the host xylem. In many areas of the world these parasites are a threat to agriculture but so far very limited success has been achieved to minimize losses due to these parasitic weeds. Considering the carotenoid origin of the strigolactones, in the present study we investigated the possibilities to reduce strigolactone production in the roots of plants by blocking carotenoid biosynthesis using carotenoid inhibitors. Hereto the carotenoid inhibitors fluridone, norflurazon, clomazone and amitrole were applied to rice either through irrigation or through foliar spray. Irrigation application of all carotenoid inhibitors and spray application of amitrole significantly decreased strigolactone production, Striga hermonthica germination and Striga infection, also in concentrations too low to affect growth and development of the host plant. Hence, we demonstrate that the application of carotenoid inhibitors to plants can affect S. hermonthica germination and attachment indirectly by reducing the strigolactone concentration in the rhizosphere. This finding is useful for further studies on the relevance of the strigolactones in rhizosphere signalling. Since these inhibitors are available and accessible, they may represent an efficient technology for farmers, including poor subsistence farmers in the African continent, to control these harmful parasitic weeds.     

Traditional yam cultivation on Pohnpei,Eastern Caroline Islands,Micronesia

A project was undertaken during 1988 to investigate traditional yam (Dioscorea spp.) production on Pohnpei Island in the Eastern Carolines. Yam is the most important crop on the island and figures prominently in the traditional prestige system. One hundred seventy-seven locally-recognized cultivars of yam representing 5 species were reported by informants. Yam production is seasonal, complementing the breadfruit season. The yam season is delineated by a series of feasts and ceremonies. In order to insure a steady supply of yams during this time, farmers plant several cultivars, use different trellising methods, and employ other techniques. Cultivation of yams is done mainly under live breadfruit trees, although several other species of trees are used, and are often ring-barked to improve yam growth. Taboos and magic are still employed by many farmers. Although production per unit land area is low under the traditional system, yams of large size are produced which are highly suitable for prestige purposes.     

Resource Use in a Landscape Matrix by an Arboreal Primate: Evidence of Supplementation in Black howlers (Alouatta pigra)

Across the tropics, landscapes of continuous rain forest are being replaced by forest fragments embedded in a matrix of pastures and farmlands. This conversion has endangered many species, including arboreal primates. Species vary, however, in how they are able to supplement their diets from the matrix, although this is rarely studied in primates. We studied two groups of black howlers (Alouatta pigra) for a total of 1156 h, one inhabiting a smaller fragment (0.4 ha) and the other a larger fragment (20 ha). monkeys inhabiting the smaller fragment spent more time in the matrix than in the habitat fragment, spending 50 % of their time (335 of 667 h) in an abandoned mango (Mangifera indica) plantation, 8.8 % in scattered trees, and 0.2 % in pastures. In contrast, monkeys in the larger fragment spent 75 % of their time (368 of 489 h) in the forest fragment and only 25 % of their time in the matrix. Feeding in the matrix accounted for 53 % and 12 % of the foraging time for groups in the smaller and larger fragments respectively. We suggest that Alouatta pigra can use resources in the matrix to supplement their diet by means of crop raiding or taking other resources in many fragmented landscapes and that this may be true also for many fragment-dwelling primates. It is important to include a consideration of the matrix in conservation planning, considering both the total resources available to primates and the consequences of crop raiding for farmers.     

European organic dairy farmers’ preference for animal health management within the farm management system

The expertise and knowledge of veterinary advisors on improving animal health management is key towards a better herd health status. However, veterinary advisors are not always aware of the goals and priorities of dairy farmers. To dairy farmers animal health is only one aspect of farm management and resources may be allocated to other more preferred areas. Veterinary advisors may experience this as non-compliant with their advice. To explore the preferences of European Union (EU) organic dairy farmers for improved animal health management relative to other farm management areas an adaptive conjoint analysis (ACA) was performed. A total of 215 farmers participated originating from organic dairy farms in France (n=70), Germany (n=60), Spain (n=28) and Sweden (n=57). The management areas udder health and claw health represented animal health management whereas barn, calf and pasture management represented potential conflicting management areas. Results indicate that EU organic dairy farmers differ in their preferences for improved animal health management within the farming system. In general, improved calf management was the most preferred area and improved claw health management was found to be least preferred, the remaining areas were of intermediate interest. Cluster analyses on claw health measures and udder health measures resulted in respectively seven and nine distinct preference profiles. The results indicate a high degree of variation in farmers’ preference, which cannot be explained by the typical herd characteristics. With the individual preferences revealed by ACA, a veterinary advisor can now find out whether his intended advice is directed at a favourable or unfavourable management area of the farmer. If the latter is the case the veterinarian should first create awareness of the problem to the farmer. Insights in individual farmers preferences will allow veterinary advisors to better understand why farmers were incompliant with their advice and improve their advice by showing, for example, the potential benefits of their advice.     

Challenges to using neem (Azadirachta indica var. sianensis Valenton) in Thailand

The use of botanical insecticides based on the neem seed (Azadirachta indica var.siamensis Valeton) shows strong potential in the fight against important agricultural pests. Unfortunately, its use in rural Thailand is extremely limited. This study examines the efficacy of neem extracts processed under rural conditions; identifies factors that influence local farmers’ adoption of neem products; and proposes recommendations to promote the use of neem insecticides. The principal findings are: in field trials conducted under typical rural conditions, neem did not adequately control major pests of yard-long beans (Vigna sesquipedalis); and intensity of vegetable production, knowledge of neem insecticides and availability and accessibility of neem products strongly influence farmers’ adoption of neem products for pest control.     

The Ethnobotany and Ethnopharmacology of Wild Tomatillos, Physalis longifolia Nutt., and Related Physalis Species: A Review

The Ethnobotany and Ethnopharmacology of Wild Tomatillos, Physalis longifolia Nutt., and Related Physalis Species: A Review. The wild tomatillo, Physalis longifolia Nutt., and related species have been important wild-harvested foods and medicinal plants. This paper reviews their traditional use as food and medicine; it also discusses taxonomic difficulties and provides information on recent medicinal chemistry discoveries within this and related species. Subtle morphological differences recognized by taxonomists to distinguish this species from closely related taxa can be confusing to botanists and ethnobotanists, and many of these differences are not considered to be important by indigenous people. Therefore, the food and medicinal uses reported here include information for P. longifolia, as well as uses for several related taxa found north of Mexico. The importance of wild Physalis species as food is reported by many tribes, and its long history of use is evidenced by frequent discovery in archaeological sites. These plants may have been cultivated, or ??tended,?? by Pueblo farmers and other tribes. The importance of this plant as medicine is made evident through its historical ethnobotanical use, information in recent literature on Physalis species pharmacology, and our Native Medicinal Plant Research Program??s recent discovery of 14 new natural products, some of which have potent anti-cancer activity.     

West African Cattle Farmers’ Perception of Tick-Borne Diseases

Worldwide, cattle production is struggling to face the negative impacts caused by ticks and Rhipicephalus (Boophilus) microplus is one of the most harmful ticks for livestock. Most of the people in West Africa depend on cattle farming and subsistence agriculture. The presence of ticks on cattle is a major problem faced by smallholder farmers who fight for their livelihood. National and regional tick control programs could assist these rural communities in protecting their livelihoods against ticks and tick-borne diseases, but only if they take into account the targeted herders and their perception on cattle management and tick control. This paper aims to provide a better insight in the socio-economic characteristics of Beninese cattle farmers, and their perception on tick burden, as well as to document common tick control strategies. Different tick species and their seasonality are well understood by cattle herders. For tick control, many still use manual tick removal, especially in the north of the country. The high cost of acaricides, the lack of financial means of African farmers, and of the local stockbreeders in particular, limits the use of acaricides in livestock breeding in Benin. While aiming to increase the meat or milk production of their animals, stockbreeders who can afford it sometimes turn to an abusive use of acaricides, which might in time lead to an increase in tick resistance. This study remains one of the rare studies to report extensively on the perceptions of West African cattle herders.     

Lycianthes moziniana (solanaceae): An underutilized Mexican food plant with “new” crop potential

Lycianthes moziniana is an agrestic (weedy) perennial encouraged by traditional farmers for its edible, sweet-tasting fruits. This species is endemic to the Mexican highland plateau and Oaxaca where the ethnotaxonomic and ethnohistoric data reflect a long-standing relationship with human populations. Today, the fruits of this plant are used for domestic consumption, small-scale commercialization, and ceremonial purposes. To ensure the production of fruits, traditional farmers afford the plants a special management which has evolutionary repercussions. Recently, modern agricultural practices have placed this species in danger of extinction. Preliminary chemical analyses and yield data suggest thatL. moziniana is particularly well-suited for development as a “new” crop for Mexico.     

Behaviour of goats,sheep and cattle and their selection of browse species on natural pasture in a Sahelian area

A study was conducted in the Sahelian zone of Burkina Faso of the behaviour of cattle, sheep and goats on natural pasture and their preference for browse species. Concurrently, a survey was undertaken on a sample of farmers (herders, women and livestock owners) in the study area to estimate the indigenous knowledge of browse species and their utilisation by ruminants. A herd of cattle and flocks of sheep and goats belonging to farmers were followed on pasture, each species during three consecutive days each month, from May 2003 to April 2004, and their activities were recorded regularly every 15 min, as well as the browse species selected and the height reached while browsing. The farmers had good knowledge of the browse species present in the area and their preferential classification depended on the availability of the species, their nutritive value and also other ways of utilising the species concerned. However, some divergence existed in the knowledge of farmers compared to the result from the behaviour study, e.g. some species were mentioned by farmers but not found in the inventory. There was a decline in the feeding activities of all animal species from rainy to dry season, while resting and ruminating activities were increasing at the same time. This decline in time spent feeding was more important for cattle (from 72 to 39% of total time) as they relied on the herbaceous biomass for feeding, while sheep and goats made a shift in the feeding activities from grazing to browsing when the herbaceous biomass decreased. Cattle browsed (leaves and litter) during all the study period for around 4.5% of the time spent on pasture. Sheep and goats showed a peak in browsing activity in the dry season, 28 and 52% of the time, respectively. During the whole observation period, cattle browsed 10 species, with Guiera senegalensis most often selected, with 59, 54 and 84% of browsing time, respectively, in the rainy, post rainy and dry season. G. senegalensis, Combretum micranthum and Balanites aegyptiaca were the most important species browsed by sheep among the 20 browse species selected. Goats browsed more than 20 species daily but the most preferred species were Acacia senegal, B. aegyptiaca and Pterocarpus lucens. The mean height reached by goats when browsing was higher (1.65 m) than that of cattle (1.47 m) and sheep (0.87 m). The result from this study can be used to select species for regeneration and to advice farmers on the importance of herd composition.     

Tick control practices in Burkina Faso and acaricide resistance survey in Rhipicephalus (Boophilus) geigyi (Acari: Ixodidae)

Traditional systems account for 95 % of the livestock produced in Burkina Faso. Tick infestation hampers livestock productivity in this area. However, little information exists on tick-control practices used by livestock farmers. We interviewed 60 stockbreeders working in traditional farming systems to obtain the first data on tick-control practices. Sixteen farmers (27 %) did not use conventional practices: seven removed ticks by hand or plastered cattle with dung or engine oil; nine farmers treated cattle with crop pesticides. Forty-four farmers (73 %) used mainly synthetic pyrethroids (SP; either alphacypermethrin or deltamethrin in 20 and 18 farms, respectively) and occasionally amitraz (N = 6). Intervals between treatments varied significantly depending on the chemical used: most farmers using crop pesticides (100 %), amitraz (100 %) or alphacypermethrin (80 %) adjusted tick-control to tick-burden, whereas farmers using deltamethrin tended more to follow a tick-control schedule. Perception of tick-control effectiveness significantly varied among practices: tick-control failures were more frequently reported by farmers using alphacypermethrin (55 %) than by those using either other conventional acaricides (17 %) or crop pesticides (0 %). We investigated whether this could indicate actual development of SP-resistance in cattle ticks. First, using the larval packet test technique, we confirmed that the computation of LC₅₀ and LC₉₀ was repeatable and remained stable across generations of the Rhipicephalus (Boophilus) geigyi Houndé laboratory strain. We then collected from the field fully-engorged female R. geigyi to evaluate the SP-resistance relative to the Houndé reference strain. We did not detect any case of SP-resistance in the field-derived R. geigyi ticks.     

Farmers' management of cabbage and cauliflower pests in India and their approaches to crop protection

Cabbage (Brassica olearaceae var. capitata) and cauliflower (Brassica oleracea var. botrytis) are two major vegetables produced and consumed in India. Over the years, they have been cultivated more intensively. This has resulted in higher rates of pest infestation, especially by the diamondback moth (Plutella xylostella) and higher pesticide use. This, in turn, has contributed to insecticide resistance, environmental degradation, and human health impacts, which have triggered a growing interest in alternative management techniques. There is a dearth of knowledge on current pest management practices in cabbage and crucifer. Knowledge about pest management practices is necessary to develop appropriate strategies such as Integrated Pest Management. The main purpose of this study was to obtain comprehensive information on pest management practices among farmers growing cabbage and cauliflower in India.A survey was conducted in the states of Gujarat, West Bengal, and Karnataka from October 2006 through January 2007. Three hundred farmers were interviewed to obtain information on pesticide use in cabbage and cauliflower production, the cost of pesticide use, and socioeconomic characters that influence cabbage and cauliflower production.Farmers relied on pesticides as the major and often exclusive crop protection strategy. Ten of the active ingredients (16.4% of all pesticides reported by all farmers in this survey) were listed as extremely or highly hazardous (classes Ia and Ib) by the World Health Organization. The results confirmed that pesticide use differs between states of India, but that location alone does not determine pesticide spraying pattern. A regression model was used to identify determinants of pesticide application frequency and pesticide cost per hectare. After controlling for location, individual level variables, such as age, education and experience, had significant effects on how often farmers sprayed. Farmers also spent more for pesticides, and sprayed more frequently on cauliflower than on cabbage and on open-pollinated varieties than on hybrid varieties.Our findings highlight the excessive use of pesticides in cabbage and cauliflower, and the reliance on pesticides as the only pest management strategy. The results confirm the need for alternative management strategies. Bt vegetables may be one of these alternative strategies. However, it is questionable whether cultivation of Bt vegetables will reduce the strong reliance on pesticides. Small-scale farmers will need training in the identification of pests, natural enemies, basic ecology, and integrated pest management strategies to ensure sustainable and safe vegetable production.     

Towards a Solution to the Goose-Agriculture Conflict in North Norway, 1988–2012: The Interplay between Policy,Stakeholder Influence and Goose Population Dynamics

This paper presents results from a multidisciplinary study of a negotiation process between farmers and wildlife authorities which led to an agricultural subsidy scheme to alleviate conflicts between agriculture and geese in Norway. The Svalbard-breeding population of pink-footed geese Anser brachyrhynchus has increased considerably over the last decades and conflicts with farmers have escalated, especially at stopover sites in spring when geese feed on newly sprouted pasture grass. In Vesterålen, an important stopover site for geese in North Norway, farmers deployed scaring of geese at varying intensity dependent on the level of conflict during 1988–2012. We assessed the efficiency of a subsidy scheme established in 2006, in terms of its conflict mitigation, reflected in a near discontinuation of scaring activities. The presence of pink-footed geese was analysed in relation to scaring intensity, the total goose population size and the increasing occurrence of another goose species, the barnacle goose Branta leucopsis. Scaring significantly affected the number of geese staging in Vesterålen, both in absolute and relative terms (controlling for total population size). The geese responded immediately to an increased, and reduced, level of scaring. Despite the establishment of the subsidy scheme, the number of pink-footed geese has recently declined which is probably caused by the increasing number of barnacle geese. For the farmers, the subsidy scheme provides funding that reduces the economic costs caused by the geese. Sustaining a low level of conflict will require close monitoring, dialogue and adaptation of the subsidy scheme to cater for changes in goose population dynamics.     

Enhancement of rice production using endophytic strains of Rhizobium leguminosarum bv. trifolii in extensive field inoculation trials within the Egypt Nile delta

This study assessed the ability of biofertilizer inoculants containing Rhizobium leguminosarum bv. trifolii to enhance production of rice (Oryza sativa L.) under actual agricultural conditions in the Nile delta. Large-scale field experiments evaluated 5 rice varieties inoculated with 7 endophytic rhizobial strains during 5 growing seasons, including at sites ranked as the world’s highest in rice production. Inoculation with single strains or multi-strain consortia significantly increased grain yield in 19 of the 24 trials. By combining superior rhizobial inoculants with agricultural extension training, grain yield increased up to 47% in farmers’ fields, with an average increase of 19.5%. Data on rice straw production, harvest index and the agronomic fertilizer N-use efficiency also indicated positive agronomic benefits of rhizobial inoculation. These results establish the merit of deploying our biofertilization strategy using selected rhizobial strains to promote rice production capacity while reducing the need for additional chemical N-fertilizer inputs to maintain agricultural sustainability and acceptable production economy. Technology transfer of this important translational research can significantly help to alleviate hunger and meet the nutritional needs of many people in developing countries.     

Occupational Exposure to Swine,Poultry, and Cattle and Antibody Biomarkers of Campylobacter jejuni Exposure and Autoimmune Peripheral Neuropathy

Introduction

Foodborne Campylobacter jejuni infection has been associated with an increased risk of autoimmune peripheral neuropathy, but risks of occupational exposure to C. jejuni have received less attention. This study compared anti-C. jejuni IgA, IgG, and IgM antibody levels, as well as the likelihood of testing positive for any of five anti-ganglioside autoantibodies, between animal farmers and non-farmers. Anti-C. jejuni antibody levels were also compared between farmers with different animal herd or flock sizes. The relationship between anti-C. jejuni antibody levels and detection of anti-ganglioside autoantibodies was also assessed.

Methods

Serum samples from 129 Agricultural Health Study swine farmers (some of whom also worked with other animals) and 46 non-farmers, all from Iowa, were analyzed for anti-C. jejuni antibodies and anti-ganglioside autoantibodies using ELISA. Information on animal exposures was assessed using questionnaire data. Anti-C. jejuni antibody levels were compared using Mann-Whitney tests and linear regression on log-transformed outcomes. Fisher’s Exact Tests and logistic regression were used to compare likelihood of positivity for anti-ganglioside autoantibodies.

Results

Farmers had significantly higher levels of anti-C. jejuni IgA (p < 0.0001) and IgG (p = 0.02) antibodies compared to non-farmers. There was no consistent pattern of anti-C. jejuni antibody levels based on animal herd or flock size. A higher percentage of farmers (21%) tested positive for anti-ganglioside autoantibodies compared to non-farmers (9%), but this difference was not statistically significant (p = 0.11). There was no significant association between anti-C. jejuni antibody levels and anti-ganglioside autoantibodies.

Conclusions

The findings provide evidence that farmers who work with animals may be at increased risk of exposure to C. jejuni. Future research should include longitudinal studies of exposures and outcomes, as well as studies of interventions to reduce exposure. Policies to reduce occupational exposure to C. jejuni should be considered.