A small study involving children and adults in Canada showed that fish and shellfish allergies do not usually heal with time.
Allergy to fish and oysters, along with the sensitivity of nuts, is the biggest cause of severe allergic reactions, the team wrote in the journal Allergy and Clinical Immunology: Practice. But little is known about how long seafood allergies continue."Sensitivity of fish and oysters ... represents the majority of life-threatening sensitivities among adults, but the research done on them is far less than other types of allergies," doctor Moshe Ben Shushan told Reuters Health in an e-mail.
"Patients should understand the potential pathway to food allergies and so far there is no data on the natural solution to this sensitivity," said Ben Shushan, a pediatric sensitivity specialist at the McGill University Medical Center in Montreal.
"Our group has, for the first time, sought to bridge this knowledge gap," Reuters quoted Ben Shoshan as saying.
Data from Canada and the United States indicate that about 0.5 percent of adults and about 1 percent of children are allergic to fish, the researchers said. Between 1.4 and 2.5 percent of adults and between 0.5 and 2 percent of children are allergic to oysters.
To determine how long this sensitivity ended over time, the researchers studied 63 patients, 37 of whom were allergic to fish, 25 were allergic to oysters and one had both.
Participants in the study, or their relatives, completed questionnaires about the first and worst reaction to eating fish and oysters and allergies, such as rash, itching, colds, cough, abdominal pain, dizziness and difficulty breathing. The researchers also reviewed their medical records.
After follow-up of children and adults for six years, researchers found that each year the sensitivity of less than one percent of participants disappeared.
"The sensitivity of seafood is rarely cured - the cure rate of allergies from fish or oysters is less than 1 percent within a year of follow-up," Ben Shoshan said.
