Anchovy is a food which may result in allergy symptoms in sensitised individuals.

NB: In Germany and Scandinavia the names Anchovis or Ansjovis are used for spice-cured sprat (Sprattus sprattus) or small herring, which are different species.

Anchovy Allergy Test: Allergen Exposure

The anchovy is a small forage fish, classed as an oily fish, and commonly found in marine waters, although there are freshwater populations in South America. They are fished by humans both for use as food and as bait for larger fish such as tuna and sea bass.

They can be eaten fresh, but are traditionally gutted and salted, brined and then packed in oil or salt, often in cans. This preserves them and allows them to be stored and transported more easily. The process results in a characteristic strong flavour and imparts a grey colour to the flesh. The largest supplier of canned anchovies is Morocco.

They may also be pickled in vinegar, in which case the flesh retains its white colour, and the fish has a milder flavour. Anchovies are also processed into anchovy paste and anchovy essence, both used in cooking. They are also a popular pizza topping.

Their strong flavour makes them an ideal flavouring for sauces, including Worcestershire sauce, remoulade and many fish sauces, and in some versions of Café de Paris butter.

In Roman times, they were believed to have aphrodisiac properties.

Anchovy Allergy Test: Allergen Description

Anchovies, like all fish, contain a number of proteins with allergenic potential.

Anchovy Allergy Test: Potential Cross-Reactivity

Studies suggest that fish-allergic subjects may be clinically sensitive to more than one species of fish.

Species within groups of fish, like Gadiformes (examples: codfish and hake) and Scombroid fishes (examples: mackerel and tuna) seem to share allergenic components. The overlap of allergen specificity between the groups seems to be moderate or even small.

For example, 35% of a group of codfish-sensitive children showed sensitivity to anchovy.

Significant cross-reactivity has been demonstrated between mackerel and anchovy.

Anchovy Allergy Test: Clinical Experience

In one study of thirty-nine individuals who reported fish allergy, 85% experienced allergic symptoms within 30 minutes after ingesting fish. The most frequently reported symptoms were hives (69%), itching (69%), and wheezing/chest tightness (54%). The most prevalent positive reaction was to anchovy (73%).

In another study, skin testing with a commercial anchovy extract was reported to give false positive results in 75% of non-atopic controls, presumably because of the high content of histamine.

Allergic reactions to anchovy usually occur when the fish is eaten. Severe reactions generally begin within minutes of ingesting the food. Reported symptoms include digestive distress, including stomach ache, cramping, diarrhea or vomiting.

Symptoms may also be triggered when fish protein from the anchovy is inhaled during the cooking process or when the fish comes into direct contact with an allergic person’s skin.

It is not unusual for the onset of fish allergies to happen in adulthood, and women are more likely to be affected than men. Fish allergies usually last throughout the patient’s lifetime.

Other reactions

Anchovy has a high content of histamine.