Warning: Dogs are stolen in Biggin Hill
A Career as a Veterinary Surgeon
A Career as a Veterinary Nurse
The Truth about Fleas |
|
Martin C. James |
Although fleas are a year-round problem, now is the time to start treating your pets and stop the summer build-up that we so frequently see. Fleas are incredibly tough insects, which can reproduce at an incredible rate.
The Life Cycle of the Flea
The female flea lays eggs whilst on its host animal, often while the
animal is sleeping. The eggs are white, oval shaped and 0.5mm long. They
drop into the local area and will hatch within 2 – 10 days depending
on the temperature. The larvae tend to seek out dark, humid areas, so
burrow deep into carpets, into cracks between floorboards and around the
edges of rooms. They feed on any organic matter in house dust –
primarily dead skin cells and the droppings (or dirt) from adult fleas.
The larvae need a temperature of 10 – 30 C, any colder and they
die. 
Humidity
is also important – too dry and they will desiccate. Larvae can
develop outside, preferring long vegetation or shaded areas – paving
or short sunny lawns will finish them off. In a warm environment with
plenty of food, larvae can grow and spin a cocoon to form a pupa within
10 days. The flea can stay in the pupa for anything from 10 – 14
days, waiting for the right temperature, humidity and for the presence
of animals or humans to feed on - they sense vibrations from passing hosts!
Once emerged, adult fleas need to find an animal to feed on within 12
days. After her first meal a female can start to lay eggs within 36 hours
and can lay between 20 – 50 eggs per day for up to a 100 days! Under
ideal conditions, one adult female can be responsible for producing 20,000
adult fleas and 160,000 immature larvae and pupae in 60 days!
How Fleas Hurt Our Pets
The
main problem is obviously irritation. This is often variable between
animals because some dogs and cats become allergic to the flea saliva,
whilst others tolerate lots of fleas quite happily. This latter group
will act as a source of infection to allergic animals so the golden
rule that ALL ANIMALS IN THE HOUSE SHOULD BE TREATED FOR FLEAS must
be followed.
- 72 fleas can consume 1ml of blood per day, so severe infestations
on very small animals, especially puppies and kittens, can cause severe
anaemia and even death – hard to believe but tit does happen every
year.
- Fleas also carry a tapeworm, Dipylidium caninum, which is ingested
when a host animal grooms a flea off itself. IF YOUR PET HAS FLEAS,
IT WILL HAVE WORMS AS WELL.
- Finally fleas can bite humans – they prefer our fur-covered friends, but if you have a bad infestation in your house they will attack your ankles and calves, or come at you from your sofa, biting your back.
Controlling the problem
Unfortunately, no flea preparation yet invented is 100% effective. This means a huge number of our pets will be carrying at least a few of the critters, and there is also always the potential in the warmer months to catch fleas from the outside where foxes, and hedgehogs, and other peoples’ pets have been. If we can’t rid our animals of fleas 100%, we must use regular control to stop fleas reaching epidemic levels in our houses. So where do we start?
The house
As
most of the fleas’ life cycle is spent in your pet’s immediate
environment, it is unquestionably as important to treat the house as it
is to treat your pet. The main problem is likely to be where your animal
sleeps although flea eggs can drop off in any area visited by your pets
– with cats this normally involves the whole house.
Vacuuming is a good place to start – the vibration encourages adults to emerge from pupae and the suction will remove eggs, some larvae and some of the dust that the larvae live on. Professional steam cleaning will also kill both larvae and adult fleas, and reduce dust levels further although it is important to dry the carpets as rapidly as possible as any larvae left behind will enjoy the increase in humidity within the carpet.
It is important to treat the house with an insecticide soon after hoovering or steam cleaning, as any eggs or pupae left behind will quickly hatch and re-infest the house.
Insecticidal sprays – these contain Pymethrin or pyrethroids which kill adult fleas. However they are quickly degraded by light so only remain active in the environment for a few days. The best sprays, such as Vetkem Acclaim, also contain an insect growth regulator which stops larvae developing into adults. These can remain active for up to 12 months.
When spraying a room first remove any birds or fish. Start in the centre of the room and work towards the edges. Don’t forget to spray soft furnishings and under furniture. Don’t scrimp with the spray. Being liberal with it at this stage will save you having to do it all over again in a few months. However in badly infested houses, fleas can reappear in 5 – 14 days. This is because the pupae are not killed by the spray unless they are thoroughly soaked in it, so often they will continue to develop and emerge unaffected. A second treatment at this stage will solve the problem.
Unfortunately spraying your house is time consuming and unpleasant to do, but unless your house is completely devoid of carpet and soft furnishings (and that includes beds), it is a necessity. One option is to use a professional service which can save a lot of hassle in the long run. They may even do a repeat treatment free of charge if fleas reappear.
Other Treatments:
Sodium Borate Crystals can be sprinkled into the carpet and on soft furnishings.
Any larvae that eat them are killed and the crystals absorb water to dehydrate
eggs and larvae. The effect can last 6 months to 1 year.
Intermittently blinking light traps are available which attract fleas. However their efficacy is limited.
Treating your pet
As no treatment is 100% effective, the regular use of products is essential – ideally all year round, although occasionally you can get away with stopping treatment for the coldest winter months. All animals in the house must be treated even if they are not showing any signs of infestation. Bear in mind that some products on your dog will be washed off by swimming and bathing, and flea allergic cats and dogs which groom excessively can clean a lot of the medication off themselves.
The choice of which product to use can be confusing as there is now such a range on the market.
Frontline
– contains Fipronil – comes as either a spray or as a spot-on
(a pipette that you empty onto the skin on the back of the animal’s
neck). If is effective against fleas, ticks and some mites. After application,
the fipronil is absorbed into the sebaceous glands in the skin from where
it is gradually released onto the coat. The spray works instantly, the
spot-on takes 24 hours to reach maximum effectiveness. It is normally
used monthly in cats and every 2 months in dogs, although it can be used
as often as every 2 weeks in bad infestations, or for tick control.
Stronghold – contains selamectin – a spot-on
preparation.
As well as treating fleas and mites it will also kill any intestinal roundworms.
It probably has some effectiveness against ticks and lungworms as well,
although trials have not been done. It is particularly useful if fox mange
is suspected, and also with the treatment of ear mites in cats. It is
normally used monthly, although can be used every 2 weeks in bad cases.
After application, it can be 36 – 48 hours before all fleas are
killed. The drug is actually absorbed through the skin and stored in the
animals fat so shouldn’t be washed off by swimming etc – useful
if your dog loves the water.
Advantage – contains imadocloprid – another
spot-on treatment.
This kills fleas only, but will work within 12 hours of application. Again
it is used monthly, but can be applied every 14 days in bad cases.
Both Advantage and Stronghold are also supposed to kill larvae in the environment. This happens because treated pets shed dead skin cells into the house which are impregnated with the product. As larvae eat these, they are killed. However in anything except mild infestations, treatment of the environment with a spray is also necessary.
Pet shop and supermarket spot-ons. These contain either permethrins which lose their activity very quickly and are toxic to cats, or an insect repellent. They are nowhere near as effective as veterinary products and in fact, we hear an awful lot of complaints from pet-owners about how useless they are.
Flea collars – they can reduce flea numbers by 50 – 90% under ideal conditions. However they are less effective in medium to large animals and won’t be sufficient for bad infestations or if an animal is flea allergic. They remain effective against fleas for only 4 weeks in most cases, despite claims to the contrary, and studies have shown that typically owners leave them on for 9 months! Cats can be very good at losing them as well!
Powders – these are generally pretty ineffective. It is difficult to get them through dense undercoats thoroughly, and they just fall out of short coats. The powder can also dry out the skin and dull the coat. Overdosing with them can cause toxicity.
Program – contains lufenuron. Given either by a monthly tablet to dogs, a monthly oral suspension to cats or by a 6 monthly injection to cats. It is stored in the animals’ fat and ingested by the fleas as they bite. The drug caused female fleas to lay sterile eggs. Also any larvae that eat faeces passed by medicated fleas will not develop into adult fleas. The treatment works best to prevent a build up of fleas in a house with only one or two animals. If you have a bad infestation already other measures will be necessary. The treatment must be given to all cats and dogs in the house.
Darwin Veterinary Centre Recommendations
We
tend to advise Frontline spot-on as the mainstay treatment for cats and
dogs, and Vet-kem Acclaim for the house, as it lasts up to 12 months.
The house should be treated once a year in spring or early summer for
prevention or whenever you have a problem. Frontline should be used at
least every 2 months in dogs, and every month in cats.
If you have a lot of foxes in your area, Stronghold can be a good idea instead of Frontline to stop your dog getting fox mange. As it also treats roundworms in cats and dogs, and ear mites in cats, it can be used for these problems as well. It is more expensive than Frontline, especially in dogs where application should be twice as often as Frontline. If your rabbit gets fleas, then Advantage, used monthly, is the only licensed treatment.
If you have a cat (or dog) that doesn’t like having Frontline applied then Program Injection for cats every 6 months or the monthly tablet for dogs is an easier alternative. However, bear in mind that all cats and dogs in the house should have Program as well, and it is often not that effective in severe infestations, or if you have more than 2 or 3 animals.
If you have any queries about fleas or other parasites, please do not hesitate to contact the surgery – we’ll do our best to answer all your questions.
| Top |
© Darwin Veterinary Centre Limited 2002-2006. All rights reserved.