Some yellow jackets more venomous than others

By Anne Harding

NEW YORK (Reuters Health) – A yellow jacket sting can be
more dangerous if a certain species of the insect is doing the
stinging, a new study shows.

Of the two most common yellow jacket species found in the
eastern US, Vespula maculifrons — which tends to live in large
underground nests — is much more likely to cause a systemic
reaction than is Vespula germanica, Dr. David B. K. Golden of
the Johns Hopkins Asthma and Allergy Center in Baltimore and
colleagues found.

This means that if a person with a history of severe
reactions to yellow jacket stings gets stung again without
reacting severely, the milder sting may simply have come from
the milder species — and doesn’t mean the person has outgrown
the allergy, Golden explained in an interview with Reuters

“What we hear from people is that ‘oh it was a fluke, it
will never happen again’,” he said. “That’s certainly not
something you can count on.”

A systemic reaction extends beyond the area where a person
was stung, and can range from mild responses such as
light-headedness to potentially fatal reactions such as
swelling that closes off the windpipe or a dramatic drop in
blood pressure.

Golden and his team initiated their study to determine why
some people react severely to yellow jacket stings and others
don’t. They tested reactions to yellow jacket venom in 111
healthy volunteers, who received a total of 175 sting
challenges over a three-year period, and report the results in
the Journal of Allergy and Clinical Immunology.

V. maculifrons was more likely to produce a systemic
reaction than V. germanica, the researchers found. And these
reactions were more common among people who had experienced
such a reaction previously. Among people with a history of
systemic reactions to yellow jacket stings, 41 percent had a
systemic reaction to V. maculifrons. But among those who had
not experienced systemic reactions in the past, just 3 percent
exhibited systemic reactions to V. germanica.

The findings show that even if a person has escaped a
severe reaction with a yellow jacket sting in the past, he or
she is not safe from having one in the future, the researchers

Anybody who has suffered a severe reaction to a wasp, bee
or yellow jacket sting should be evaluated by an allergist,
Golden told Reuters Health, because immunization is available
for allergies to each type of venom that is 98 percent
protective against future severe reactions.

SOURCE: Journal of Allergy and Clinical Immunology,