Bites & Stings
We all know how nosey our pets are, being an extension of ourselves, and sometimes just as with us, that nose gets them into trouble. As summer arrives and insect numbers climb, a nasty shock lurks amongst our gardens and trapped against our window panes. Our precious cats and dogs can be on the receiving end of sometimes painful, and even dangerous insect bites and stings.
The type and severity of a reaction is dependent upon the species of insect, location and number of bites, and the immune system of the individual animal. Signs usually occur within about 20 minutes of the bite and can range from local pain up to a life threatening super-allergic reaction called anaphylaxis.
Their literal nosiness means our pets are most often stung round the nose and mouth. Severe reactions include swelling of the eyelids, ear flaps, lips, tongue and sometimes the entire face. This restriction of the airways may cause difficulty in breathing.
In an anaphylactic reaction, animals may go into shock with symptoms such as wheezing, weakness, unconsciousness, pale mucous membranes (gums), weak pulse, increased heart rate, a high fever (conversely a low temperature is also possible), trembling, distress, vomiting, diarrhoea and collapse. This type of reaction is an emergency and requires immediate veterinary treatment.
More often though, the pain or swelling is local or results in urticaria (sometimes called wheals or hives), a multitude of itchy raised skin bumps. Even a mild reaction can progress in severity so make sure if your pet is bitten, you observe him/her closely for the next 12 to 24 hours.
THE USUAL SUSPECTS
SPIDERS
Most New Zealand spider bites are mild and just cause local swelling, redness, and itching. Some individual animals can have an allergic reaction to a sting or bite that may result in mild hives, facial swelling, vomiting, difficulty breathing or even collapse. The spider bites we see are often around the less hairy abdominal area, the pet lying on a spider that hasentered their bedding.
What to Do:
Apply cool compresses to the area. To help neutralize some of the acidic venom, apply a paste mixture of baking soda and water to the sting area.
Your pet should be examined immediately by a veterinarian if there is significant swelling, pain, breathing difficulty or collapse.
What NOT to Do:
Do not administer any medications without first contacting your veterinarian or a veterinary emergency hospital, UNLESS YOUR VET HAS PROVIDED YOUR PET WITH A SUPPLY OF MEDICATION SPECIFICALLY FOR THESE SITUATIONS. The veterinarian may need to examine your pet before recommending medications.
WHITE TAIL SPIDER 1 SHADOW 0
Shadow's lovely Sunday at the beach turned into a nightmare when his back started swelling and he was in a lot of pain. The vet at the emergency clinic treated him with pain relief, antibiotics and a soothing skin cream.
By the next day Shadow could hardly walk, was off his food and all the hair had started to fall out around the initial wound. He ended up loosing a big chunk of skin in the middle of the swollen inflamed area of his back and was very sore and sullen for many days.
After 5 long days the skin had started to dry around the dead area in the centre and he was starting to get back to his normal habits, his personality was returning.
White tail spiders have venom that is cytotoxic, affecting cellular tissue and is usually restricted to the local area of the bite. The initial bite is pretty painless but symptoms develop about 2-8 hours later, the skin area becomes painful and swollen Eventually blisters may form over necrotic lesions which then slough to create an ulcerated wound up to 10cm in size. It is important that if you suspect your pet could have a white tail spider bite to take them to your vet as soon as possible.
BEES & WASPS
The venom mechanism of Hymenoptera insects is in the ovipositor located in the caudal abdomen. When animals are stung, the stinging mechanism containing the venom breaks off from bees and certain wasps and embeds in the victim, permitting continued release of venom. Some wasps and hornets are capable of multiple stings, injecting large amounts of poison into the victim.
The pathologic response to bees may be allergic, anaphylactic, or toxic, depending on the degree of sensitivity of the animal, the amount of venom deposited, and whether previous sensitization has occurred.
Signs of a sting may vary from a wheal with a central red spot, swelling, itching, and pain to severe systemic responses such as disseminated intravascular coagulation (DIC), jaundice, ataxia, seizure, and sometimes death. Massive evenomation from swarm stings have been known to cause severe systemic toxic reactions and the body’s immune system to destroy all its own blood cells, immune mediated haemolytic anaemia.
If the stinger can be found, scrape it out with a credit card or other stiff material. Alternatively, use tweezers by grasping the stinger, which is located below the venom sac. If the sting just happened, don't put pressure on the venom sac, as that would inject more of the venom into the pet. Apply coldpacks to the area.
VET SPECIFIC TREATMENTS for allergic or anaphylactic reactions:
As vets we commonly use antihistamines and steroids to combat local allergic reactions to bites. Painkillers may also be required. If the reaction is severe and anaphylactic we need to really step up treatment to save the life of the afflicted pet.
Adrenaline injections are first up. Fluids and colloids are provided sufficient to maintain hydration, blood pressure and urine output. Refractory shock may require the addition of pressor agents such as dopamine or phenylephrine. Oxygen therapy and ventilatory support may also be needed in severe cases. Blood samples should be checked frequently to be prepared to administer blood products as necessary if hemolysis is severe enough to cause marked anemia. The ailing pet is also monitored for seizures and can be treated with valium of anaesthetic agents if severe.
For animals that have a history of collapsing after a sting, their owner may want to have a preloaded syringe of epinephrine available. Owners should be extensively instructed in proper injection technique and storage.
SNAKES
Let’s just be thankful we don’t have snakes here, oh and you’ll be pleased to know Shadow, and the other white tail spider patients we have had, are all fully recovered and happy despite still bearing the physical scars of their ordeal.
Flea Facts
BUSTING THE FLEA MYTHS
This has got to be an opportune time to bust open a few myths regarding our little local creeping parasites, FLEAS. Fleas love the heat. With this spectacular summer comes a hoard of the biting, jumping, blood suckers.
Please don’t dismiss them as a problem simply because you’ve only noticed one of the little suckers. The key is to wipe them out early.
Each female can lay 2000 eggs and only 5% of fleas are present in their adult form, so for every flea there is another 19 in egg or pupal form waiting in the shadows beneath you.
Adult fleas spend only 10% of their time on a cat or dog to feed, the rest of their day consists of running around your floors, carpets or lawns. This lead to the common statement; “but I haven’t seen any fleas on him” ….. doesn’t mean anything.
Now, doing some math’s, for every adult flea you find on “Old Yella” we’ve now got another 9 adults in your home and 190 juveniles busy developing at light speed in their ideal climate of 28 degrees and high humidity, i.e. February in Auckland.
The other big reason to wipe out each and every one of these parasites is that many cats and dogs are allergic to the bite, to the flea saliva. In these individuals a couple of bites will cause a massive hypersensitivity reaction leading to self mutilation.
In the current climate many clients are finding the need to apply good safe topical flea products at least every 4 weeks (sometimes every 2 to 3), the flea burden being massive at present.
Be aware you will need some really effective vet only treatment to do the job properly and fleas have developed resistance to many other older products.
These newer drugs are very safe, some cleverly work by spreading along the skin oil layers and are never absorbed into the animals body, and target insects very specifically.
Certainly this regime can then be extended out to every 2 months during the winter for animals without allergic conditions.
Don’t let your pets suffer with these critters, don’t let them get established in your home, seek your vets help to hit ‘em now and hit ‘em hard.
Happy “bug” hunting, Dr Alex Melrose.
Flea Invasion
Hi Alex. Please help me, and help Jack, my West Highland White Terrier. (Editor please note this is like a white version of your Scotties, even with the same name!)
We are overrun with blood sucking fleas. I dose Jock every 6 or 8 weeks with a flea vial. I get Frontline or Advantage or something like that. It doesn’t seem to be working anymore. Jack is chewing his bum and making quite a mess. I’ve got flea bites all over my legs. I haven’t started chewing them yet but it’s pretty unbearable. What can we try? Steve & Jack.
Hi. This is happening all over the place this summer. Fleas are reveling in the heat and humidity, perfect breeding conditions for them and there are a heap of them around right now, with the females dropping up to 2000 eggs each!
Those products you mentioned are excellent and safe so I wouldn’t switch to anything else. You are just going to have to dose Jack more frequently, like many other clients of ours in the midst of this fantastic summer weather.
With many dogs swimming a lot more, that can also rapidly strip the flea treatments out of the skin. We’ve found dosing as often as every 2 to 3 weeks is required in some cases. With safe products like those mentioned in your email, you won’t be “overdosing” him, or causing any illness.
Very little of the active chemicals are absorbed into the body, mainly working by spreading through the skin oil layers and binding to hair follicles. Without increasing the frequency drastically you just won’t mop up all the fleas in your environment now, remember for every one flea on Jock there are 9 more in your floors or lawn waiting to feed.
A scary thought. As it cools off later you can dose Jock less frequently again, stretching out to every 2 months over winter for animals without skin allergies. So don’t throw the Frontline or Advantage out, just use them more and consider bombing the house if upon close inspection your carpets appear to be moving.
Fleas
Dear Doctor Alex, I’ve got a great 6 year old tabby cat which i rescued from a roadside ditch and bottle fed on kitten formula from 1 month of age. Xena has flourished since then and has never had a sick day in her life. I usually flea comb her and almost never find any fleas. Just the last few weeks though i‘ve had a real problem with her and fleas and have finally put a flea collar on her. The last couple of days she has been off her meals and dribbling more than usual and staying put in her cat bed. Could it be a reaction to the flea treatment? If I take the collar off what else can I try?
Lisa and Xena. Freemans bay.
Hi Lisa. An alarming number of cats are accidentally poisoned by common flea treatments available in supermarkets, and with summer fast approaching the frequency of these toxicities is going to rise again. Unfortunately a few cats die from this every year in New Zealand. In the case of flea collars the culprit is usually Permethrin. Which although marketed as natural (existing harmlessly in the environment in certain plants) it is still potentially very toxic. Certain individual cats and toy breed dogs have been shown to be very susceptible to this chemical as well as others chemicals present in cheap older-generation spot-on type products. Things can go particularly pear shaped if a product made for dogs is used mistakenly on cats. These will have higher doses of active ingredient and some have extra ingredients added which only dogs can tolerate. People can easily poison their cat by accident – buying a flea treatment they think will cost less and not reading the label properly. Signs of Permethrin poisoning certainly match those of Xena and can progress to in-coordination and seizures. Definitely remove her collar, try and wash her neck area and bring her up for us to assess for further treatment like IV fluids. I would strongly recommend only using vet only new generation safe flea products this summer.
Ticks
Hi Alex,
Just a quick question. I’ve been walking “Van”, my chocolate Labrador puppy, through One Tree Hill a lot over this summer break. He really loves the wilderness feel of it all. The other day we found a tick on Van’s skin and we pulled it off. The next day when I took him for a walk through the park I noticed a sign saying 'Cattle Ticks in this area'. So do I need to treat Van for these with special treatment or will the Advantage I've been using do the trick?
Regards, Rosie.
Hi Rosie and Van,
The New Zealand Cattle Tick is the only tick present in this country, despite it going by several names … Grass, Bottle or Bush Tick being some of them. While it prefers to feed voraciously on the blood of our cattle herds, it will quite happily feed of other stock, and on dogs. It has a seasonal life cycle. Every summer, as the temperatures climb it hatches out, jumps on a stalk of long grass and waits for its motion detectors to go off, triggering a leap onto passing animals. In this case an unsuspecting, pretty much a constant state for Labradors, Labrador.
The main thing to remember with Ticks is that they have some pretty impressive mouthparts which they imbed in Van’s flesh. For this reason it’s best to kill the tick first by soaking it with alcohol or Meth’s or Frontline spray, wait 15 Minuits, and then twist the tick off. If not killed first they may leave fangs in the skin which can cause abscesses.
Frontline and Frontline spray is effective and licensed, for tick control, and is what we recommend to our clients. Keep up the park adventures but kill any ticks off before removal. Regards, Dr Alex Melrose.
Worming
Hi Martin,
I think the first thing that is important to realize is that the vast number of animals with small numbers of intestinal worms will not show you any external signs. This is a very strong reason to regularly worm all cats and dogs regardless of their apparent great health.
There are four common species of gastrointestinal worms that Barney can contract, one other which can cause problems for puppies, and three species for cats. Any pets can be infected from their mother when young and then from contact fleas, lice, grass, birds and mice.
When you do see signs of a worm burden they can be varied and non specific. Bloating of the abdomen, extra gas in the bowels and a dull, dry coat are the most common. Less frequently vomiting and diarrhea, lethargy and abdominal pain can be seen, especially in puppies and kittens who are more vulnerable, having less effective immune defences and less body reserves.
Occasionally an animal with Tapeworm will rub its rear end against the ground vigorously in an attempt to dislodge Tapeworm segments that attach themselves to the peri-anal area. As a pet owner you can sometimes see these segments as small rice like grains attached to the skin in this area.
The other of the intestinal worm species which is readily visible to the naked eye is a Roundworm which is like a very thin version of an earthworm and is passed in the pets faeces. Hookworms and Whipworms are not usually noticeable. Your vet can perform a range of faecal lab tests to identify these parasites in cases where they may be dragging down the health of an animal.
The second important reason to worm all pets regularly is the risk of human infection. Hook worm, Tapeworm and Strongyloid worms are all a health risks to humans. These can be transferred by inadvertent faecal-oral transmission (touching your mouth with your hands after playing with Barney) or some can even penetrate through your skin. In healthy adults the immune system often prevents infection but young children and immune compromised people are at risk.
In the worst cases the worm larvae can migrate through body organs doing huge damage and even causing blindness. I hope this makes it clear why all pets should be wormed every three months, an adequate period of time to cover the minimum of 8 weeks it takes for one of these parasite challenges to become active.