Travel Reference
In-Depth Information
Coral Snake Bites
Coral snakes are the only elapids native to the United States. They are found mostly in
the coastal states from southern North Carolina to Texas. The eastern coral snake inhabits
this area from Mississippi eastward; the western coral snake is found in Louisiana and
Texas. The Sonoran coral snake is found in a limited portion of southern Arizona.
These North American elapids are shy and rarely seen; bites are even less common. Re-
portedly, children may play with these snakes for hours without being bitten. Envenoma-
tion appears tooccur inless than 40percent ofthe bites that are inflicted. Coral snake bites
make up less than 2 percent of all snakebites in the United States.
Fatalities from coral snake bites apparently have not occurred since the development of
specific Micrurus fulvius antivenom. This antivenom is effective for bites of the eastern
coral snake ( Micrurus fulvius fulvius ) and the western coral snake ( Micrurus fulvius
tenere ). It is of little value for bites by the Sonoran coral snake ( Micruroides euryxanthus ),
but envenomation by this species is not severe. No deaths following its bite have been re-
ported.
Coral snakes tend to bite and hang on, sometimes chewing for as long as a minute,
whichcontrastsstrikinglywiththelightningstrikeofpitvipers.Thebitesarerarelyassoci-
ated with the local reaction—severe pain and swelling—typical of crotalid bites. Puncture
marks from the fangs usually cannot be identified, particularly if the person is intoxicated
and cannot provide a reliable account of the bite, which is a common occurrence. Some
pain may be present and may radiate up the limb. Often the first sign of coral snake and
otherelapidenvenomationispainfulenlargementoftheregionallymphnodes.Withsevere
envenomation, numbness and weakness of the limb appear within one to two hours, some-
timesless.Latersignsandsymptomsincludedrowsiness,apprehension,weakness,tremors
of the tongue or other muscles, difficulty swallowing, nausea, and vomiting. Pronounced
weaknessoftheeyeoreyelidmusclesmayoccur;pupilsmaybepinpointinsize.Breathing
may be labored. Convulsions may occur. Eventually, in inadequately treated, severely en-
venomated individuals unconsciousness and paralysis are followed by death in shock from
respiratory and cardiac failure.
Antivenomistheonlyeffectivetherapyforcoralsnakebitesandshouldbeadministered
as quickly as possible without waiting for signs and symptoms of envenomation. The limb
can be wrapped to immobilize the venom and should be splinted. Travelers to Asia and
Africa should learn the technique so it could be used for treating snakebites inflicted in
those areas.
Theobjectofpressureimmobilizationistoholdvenomatthesiteofthebiteandprevent
it from moving through lymphatics to other parts of the body. The technique has two com-
ponents: pressure to block lymphatic drainage, and immobilization to prevent the pumping
actionofmuscles.Pressureispreferablyappliedwithanelasticbandage,butanyfabricsuf-
fices in an emergency. Bandaging should begin two to four inches above the bite (between
Search WWH ::




Custom Search