What is latex?
Natural rubber latex comes from the milky sap produced by a variety of plants; however, the latex used in manufacturing comes primarily from the rubber tree Hevea brasiliensis. Natural rubber latex should be differentiated from man-made (synthetic) rubber, which refers to a combination of different kinds of particles but which does not necessarily indicate the presence of natural rubber latex. An example of this man-made rubber is latex paint. Allergic reactions are only caused by natural rubber latex from rubber tree sap.
Who is at risk?
In the 1990s, latex allergy reached epidemic levels among healthcare workers. It is estimated by Occupational Health and Safety Agency for Healthcare in British Columbia that 17% of healthcare workers have developed a latex sensitivity due to frequent exposure to powdered latex gloves. Much progress has been made in latex allergy research and awareness, and the number of healthcare workers who are newly diagnosed has now greatly diminished due to decreased use of powdered latex gloves in healthcare facilities. However, because the development of latex allergy is directly related to frequent exposure, any healthcare workers who are still regularly exposed to powdered latex gloves remain at high risk for developing the allergy.
This is also true for other workers who are frequently exposed to powdered latex gloves on the job or at home. These include food service workers, housekeeper and laundry services, laboratory technicians, ultra sound technicians, x-ray technicians and ambulance service workers. Latex gloves are sold in most stores and many people wear them for routine household chores such as cleaning and washing dishes. The continued use of latex gloves in everyday life combined with an unawareness of the allergy has now made the general population the group at highest risk. There is even a report of a horse farmer who developed a latex allergy.
Certain patient populations are prone to developing latex allergy. Children born with spina bifida often have frequent surgeries, which used to mean frequent contact with latex gloves and catheters. In fact, the first fatalities related to latex allergy resulted from the use of latex catheters used for barium enemas. In industrialized countries, the prevalence of latex allergy in children with spina bifida is about 80%. Frequent surgical intervention is also a risk factor in children without spina bifida; sensitivity to latex has been found in 34.1% of children with a history of three or more surgical procedures. However, this was not found to be true in adults (Brehler & Kutting). Patients with preexisting asthma or a history of atopy are also likely to develop latex allergies. Atopy is defined as a genetic predisposition to allergic conditions, such as asthma, eczema, or hay fever. The presence of coexisting allergies, such as, hayfever, food allergies and eczema are strongly correlated with the development of latex allergy.
Why has incidence increased?
Dr. John Downing published the first article relating allergic reactions to latex gloves, in 1933. This article appeared in the New England Journal of Medicine. He stated he had seen two surgeons during the previous six months who had dermatitis on their hands corresponding with rubber glove use. There was also a description of seven men who worked for a public utility company who wore rubber gloves eight hours every day. These men presented with redness, swelling, and fine vesicles (lines) where the gloves touched their bare hands. The same reaction occurred in two control subjects who had rubber gloves applied to their bare arms. Dr. Downing cited a letter he received from the chief chemist of a rubber company. This letter stated the company had received 20 reports of dermatitis caused by rubber gloves in the last 20 years. This letter now takes the first documented occurrence back to 1913. The chief chemist went on to say that