The severity of the reaction depends on, among other things, the amount of venom injected and the degree of
sensitisation. Some sting victims have been reported as suffering 2000 stings and surviving while others receive a single
fatal sting.
In general, honey bee venom allergens are distinct from wasp allergens. Several more suspected potent allergens have
been found solely in Vespula and Dolichovespula (the so-called Euro- or super-wasp). Clinical presentations include large
local reactions which may extend to the limbs, with disfigurement and swelling.
Highly aggressive honey bees from Africa were mistakenly released in Brazil during the 1950s. These bees colonised
nests of the native honey bees. Africanised honey bees are very much a threat in South and Central America and it is
predicted that they will be colonising the southern United States. In one study, venoms were compared biochemically and
immunochemically. These investigations concluded that the higher morbidity after sting by the Africanised bees was due
to their more offensive behaviour.
Honey bees are the only stinging Hymenopteran that nearly always leaves its fluked sting in the skin of the victim. The
venom continues to pump into the victim until the venom sac is exhausted or the sting removed.
Wasp stings are often more cause for concern. Among the Vespula species, Vespula vulgaris (the common wasp) is
responsible for inflicting the greatest proportion of stings and has a nasty disposition. They live in large colonies, with 500-
5000 individuals. When a colony is disturbed, the sentry wasps fly out, find the intruder and begin to sting. The venom
contains an alarm substance which tells the other wasps the location of the first sting. Then they continue stinging around
that site.
Whether stung by a bee or wasp, within moments susceptible people may have anxiety, a tight throat, shortness of breath,
and low blood pressure. These serious symptoms require prompt medical care, as breathing may stop and death could
occur. If you see someone having these problems, seek help by calling the emergency services. Watch and assist the
victim’s breathing if needed.
If people have ever had such a reaction, it may recur if they become exposed again. It is wise for them to wear an ID
bracelet to alert doctors. The use of anti-histamine tablets will help in the short term, but further treatment should be
sought.
Birds
Allergic reaction to birds is also possible. Pigeon fancier’s lung (PFL) is a form of extrinsic allergic alveolitis (EAA) – an
allergic reaction of the lungs to some external allergen. In PFL it is believed that small particles of dust containing pigeon
proteins cause the allergic response.
Professor Chris Feare of Wild Wings Bird Management in the UK said, “The allergens may emanate from both the pigeons’
droppings and also from the copious quantities of dust produced as pigeons shed wax from their feather sheaths, and
that any concentration of pigeons can be a source of allergens”.
There are two distinct but overlapping phases of EAA, namely an “acute” phase, which may or may not be followed by a
“chronic” phase. The acute phase is the most common and as the name of the condition suggests, is principally of
concern to pigeon fanciers. However, anyone who is exposed to a high level of “pigeon material” is at risk – so pest
controllers involved with pigeon proofing or guano clearance should take note.
Typically sufferers experience intense ‘flu-like symptoms of fever, chills, muscle ache, cough and/or breathlessness, four
to eight hours after exposure. The symptoms usually pass within 48 hours, but may persist for a week or more. Although
this attack will probably pass without treatment, it is important to visit the doctor whilst symptoms are still present,
preferably on the day of onset, as if you delay there may be no visible symptoms for the doctor to investigate.
It is important that the condition is identified as early as possible to prevent progression to the more serious chronic stage
of PFL. If detected and appropriate measures are taken early enough, acute PFL is reversible. If not detected (or ignored),
the acute phase may be followed by the chronic phase which is characterised by a type of irreversible lung damage
doctors call pulmonary fibrosis. This is very serious and in extreme cases may be fatal. The major symptoms are
breathlessness on exertion, coughing and weight loss, which can be considerable.
It can be seen that many of the symptoms are general to a number of “chesty” conditions, so it is important for sufferers
to recognise that there may be a possible link with pigeons and mention this to the doctor.
Chris Feare emphasises a further
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