1 - Human fatalities from marine animal envenomation.
locations - Human fatalities from marine envenomation
Australia, Fiji, India (Banda), New Caledonia, Okinawa (Japan),
Burma, Malaysia, India (Madras), Java (Indonesia), Okinawa
(Japan), Oman, Sri Lanka, Vietnam
Australia, California, Colombia, Fiji, New Zealand, Surinam,
Australia (Thursday Is.), East Africa, Japan, Seychelles
Indo-West-Pacific north to Okinawa, east to Philippines,
west to India and south to New Zealand (including all of Australia).
May grow to 15-20cm. in diameter with tentacles extended. Usually
yellowish-brown but when irritated, many small electric-blue rings
appear, making it look very attractive.
Minor bite from beak underneath body (often painless). The venom
is ducted to the beak from the salivary glands.
Numbness of the lips and tongue may occur within minutes. In serious
envenomation weakness and breathing difficulty develops rapidly,
which, if untreated will develop into respiratory failure.
There have been two fatalities in Australia, and one in Singapore.
Assisted ventilation for 4-6 hours, or possibly up to 12 hours
- after which spontaneous breathing usually recurs.
NOTE: the person remains
aware and conscious during this time, despite needing expired air
resuscitation, or mechanical ventilation.
All Oceans except for Atlantic: more common in tropical and
sub-tropical zones. They may reach the upper reaches of rivers,
long distances from the sea.1
Similar to land snakes except they have flattened oar-like tail.
Unlike eels, they have no gills.
Most bites are "dry" less than 10% of sea snakes
actually inject any venom. The bite is relatively painless, and
if venom is injected, is followed by symptoms including drowsiness,
nausea and vomiting, weakness, visual disturbances, breathing problems
and muscle pains or stiffness. Myolysis may cause renal impairment.
Hundreds of fatalities from sea snake envenomation have occurred
in the Countries listed in Table 8. Current estimates of the fatality
rates worldwide are around 3 per cent - at least 150 deaths annually
(Prof. David Warrell, pers. com. 1997).
Intravenous antivenom, as needed. However, the role of antivenom
in reducing the extent of myolysis is at present uncertain. . Other
measures in the management of myolysis include good hydration and
the maintenance of a good urinary output. Renal failure should be
treated along standard lines. Primary coagulopathy does not occur
in sea snake envenomation.
NOTE: Tiger snake antivenom
can be used if sea snake antivenom is unobtainable.
Care of the airway and breathing
in the usual way (intubation and ventilation). Any patient suspected
of being envenomed by a sea snake should be observed for 24 hours
following the cessation of the appropriate first aid measures.1
Tetanus immunisation should be considered. Follow-up to exclude
secondary infection may be necessary.
Indian and Pacific Oceans east to Hawaii, north to Okinawa,
Japan, and south to New Zealand (including the whole of Australia).
A cone shape with a slit-like aperture running the full length
of the shell, which may be up to 15cm in length (Figure 2).
Pain at the site of envenomation, occasionally mild, occasionally
severe and excruciating. The envenomated area may blanch, or develop
a bluish tinge, and is followed by numbness and local swelling.
In serious envenomations incoordination
and muscular weakness may develop rapidly, and swallowing, speech,
vision and hearing may be affected. Nausea, generalised pruritus
and respiratory paralysis may develop.
Up to 15 deaths have been claimed in Countries listed in Table
8, but the exact number is uncertain. Conus geographus is responsible
for the majority of confirmed deaths, with Conus textile responsible
for one death and suspected in one other.1 Recently two deaths in
Japan (from Conus geographus) have occurred (Kohama 1997, pers.
There is no specific treatment, and symptoms and signs should
be treated under the usual guidelines.1 As with any envenomation,
marine or otherwise tetanus immunisation is advised and follow-up
to exclude secondary infection may be necessary.
Worldwide tropical and sub-tropical waters. Their main contact
area with humans is in very shallow water.
Large flat-shaped fish having a whip-like tail.
Stingrays often burrow under the sand in shallow water. The
usual method of injury is a reflex forward whip of the tail when
the `wings' are trodden on. The tail contains one or more sharp
barbs, which may embed in the skin of the victim and break off,
or glance across the skin causing a laceration, which may be quite
deep and extensive.
The wound is usually (though
not always) acutely painful. Most occur on the lower limbs but there
have now been two deaths in Australia after the barb penetrated
the heart. Other serious injuries have also occurred after the barb
penetrated the chest or abdomen.
At least 17 fatalities from stingrays have occurred worldwide,
including New Zealand, Surinam, West Atlantic, Texas,23 Fiji, California,24
Australia, and many more from a fresh-water species in Colombia.1
Trunk wounds cause most of the fatalities, but acute exsanguination
has caused at least two, and one death occurred from tetanus complicating
a lower leg wound.1
The barb sheath ruptured on penetration of the affected area,
leaving tissue and venom, which will cause necrosis and infection.
The whole tract is excised, if possible, and the crater packed with
an alginate-based wick to allow healing by secondary intention.
These dressings are useful in toxin absorption and are left in place
for as long as possible. They frequently fall out at about 8-10
days, or are then easily removed without pain or damage to the healing
wound. Tetanus immunisation is advised. Follow-up to exclude secondary
infection may be necessary.
Wounds to the chest or abdomen
MUST be carefully evaluated early, by a skilled medical team with
Indian and Pacific Oceans north to China, east to Hawaii and
south to Australia.
A true fish 20-30 cms long. It has tough, warty skin, which
may be covered with slime (Figure 4). It is usually the colour of
its surrounds (frequent-ly dark brown). Along the back of the fish
are 13 spines, which when stepped on, penetrate the skin of the
victim injecting venom.
Immediate, severe pain which may cause the patient to become
frantic, or delirious. Often bluish discolouration is present around
the puncture site. The area surrounding is usually oedematous (Figure
5). Local limb paralysis, nausea and vomiting, faintness may occur.
Deaths from stonefish envenomation are rare. They are also difficult
to actually confirm, with just five deaths reported. Three are documented,
but difficult to prove conclusively: one at Mahé, Seychelles,
and the other at Pinda, Mozambique and a third reported recently,
when a SCUBA diver stepped on a stonefish underwater, panicked,
and then ascended too rapidly, death occurring from arterial embolism,
not envenomation (Kohama 1997, pers. com.). A death was reported
from Japan prior to 1989 of a male trying to put a stonefish in
a bag. He had four puncture marks and "fell down and was drowned".
Another death was reported to have occurred on Thursday Island in
1915, several days' following envenomation, although the author
believes the causative animal is in doubt.
Parenteral opioids are usually necessary; local anaesthetic
(without adrenaline) or, preferably, local nerve block. Tetanus
immunisation is advised. Follow-up to exclude secondary infection
may be necessary.
Antivenom is available for
intractable pain, or systemic symptoms.