Advice for occupational health officer

I provide some occ health advice to a local seafood factory where they deshell, bread and cook prawns. Our surveillance consists of respiratory questionnaires annually for all workers and nurse review with spirometry for any 'positives'. Next stage is peak flow diary and if suspicious IgE testing, then referral for definitive diagnosis. Several questions: Would IgE testing be a valid screening test for occupational asthma (although expensive and invasive)? Could/should IgE levels be used to monitor controls? - will the levels fall and disappear if adequate control? Is it justifiable to exclude applicants with asthma at preemployment? Thanks, Ive struggled to find this information in the literature Fergus

Occupational Asthma, Specialist, 2/20/2006, 2/20/2006,

I think that surveillance using specific IgE is a good idea. It could be done more quickly and cheaply with skin prick testing. Finding specific IgE denotes sensitisation, rather than any disease, and is sometimes less emotive and more acceptable as it doesn't depend on anything a worker has control over. It should pick up substantially more workers than have any disease related to prawns, but is a good measure of whether control measures are effective, particularly if you monitor the incidence in the first few years of exposure. For those with positive tests, a search for disease is the next step. I believe that those with prawn IgE or positive prick tests and no disease should have further efforts to reduce their exposure, and hightened (more frequent) surveillance. Specific IgE levels fall when exposure ceases, many have half lives of 6-12 months, so can be used as an indicator of allergen avoidance. Excluding asthmatics at pre-employment will not be evidence based. It is likely that atopics (positive skin prick tests to environmental allergens) and smoking are risk factors for sensitisation. Whether non-atopic asthma is a risk factor has never been tested with any cause of occupational asthma as far as I know. Those who have used IgE in surveillance include laboratory animal workers, bakers, platinum refiners, detergent enzyme workers and health-care workers exposed to latex. Botham Brit J Ind Med 44:627 (rats) Venables BMJ 299:939 (platinum) Cartier J Allergy Clin Immunol 78:344 (snow crabs) Juniper J Occup Med 27:3 (detergent enzymes) Smith Occup Med 49:147(amylase) McSharry Immunology today 7:98 (smoking and prawn allergy)

2/20/2006