Historically, throughout much of the 20th century, how we treated dogs for fleas was rather different than today. The type of treatments we use that provide flea prevention now for a month or more at a time and that have no impact on the dog themselves didn’t exist. Today, dog flea treatments usually involve spot-on products or even tablets, which are highly effective when chosen with the advice of a vet, and which have undergone rigorous testing and certification to ensure they are safe.
Historically though, throughout much of the 20th century, a huge range of products that were often potent toxins would be used after the fact to eradicate flea infestations, or to be left on the dog to repel fleas.
These included things like flea collars and powders, sprays, washes and so on, as well as a weird and wonderful range of home remedies, none of which really worked well, if at all. Using a comb to remove fleas from the coat was another approach too, which while not ineffective, is certainly time consuming as the sole method of flea treatment.
For dogs on farms or in rural areas, even products like sheep dip might have been used to try to get rid of fleas or parasites on dogs! Potent tablet-based flea products that would often make dogs quite sick themselves, but that rarely got rid of fleas too, were common as well.
Historical flea treatments for dogs then were often time consuming to undertake, very potent or toxic, and needed doing often. Another problem with them was (as is still the case in the present day) that when it comes to chemical or toxin-based flea products, over time, flea populations evolve and build up a resistance to them, rendering them ineffective. Few products repelled fleas after the fact; most were used to kill adult fleas already on the dog only.
This means even today that a product that a couple of decades ago was highly effective, recommended by vets, and the last word in comprehensive flea treatment for dogs, might not even be sold at all anymore as fleas have become resistant to it to the point that it no longer works in the UK at all.
A reasonable number of older people think fleas die off altogether in winter, or are at least no strangers to the concept that some people think this. This can be confusing to younger dog owners, at least for those who have always used reliable sources to get dog advice and whose knowledge of dogs and their care all comes from advice and authority sources developed in or recognised as relevant within the last 20 years or so.
There are some roots in the truth when it comes to the idea that fleas used to be less of an issue in winter; but this wasn’t fully true even in the past, and certainly isn’t now.
Using central heating, or keeping our whole homes heated throughout the winter wasn’t common historically. We used to heat perhaps the main living room and bedroom, and then rely on far more layers of clothing and bedding rather than trying to keep whole houses warm; and houses themselves used to be far more poorly insulated, and so cooler overall.
Double glazing, insulating lofts, and stopping draughts never really used to be a thing, and the idea of energy efficiency was an alien concept! This only really began to change in a meaningful way from the 1980s onwards.
This propensity to concentrate on personal warmth in winter rather than warming the whole house resulted in the idea that dogs didn’t harbour fleas in winter, and only needed flea treatment in spring and summer – because of the belief that fleas died off when the weather gets cold. Dogs used to be kept outside or in kennels far more too, themselves being cooler than the home.
While the idea fleas die off in winter is not correct, it does have some basis in fact, or did historically. Fleas become dormant in cold environments or cold weather, and so would become dormant in an unheated house in winter.
This doesn’t mean that the fleas died off, however – and of course, those already on the dog would be plenty warm, even if the dog was kennelled or kept outside, or in a cold room.
The fact that fleas within the home would become dormant in the cold means that householders would see less of them and be less bothered by them in winter than summer – and fleas on a dog itself would not usually jump ship to bite people when they already had a host.
This, then, resulted in the idea that fleas aren’t around in winter, and where the idea that dogs didn’t need flea treatment in winter comes from too.
When spring returned, fleas within the home that had been dormant in winter would liven up, and people would once more find themselves faced with the need to tackle both household fleas, and those on the dog.
Additionally, homes used to have a lot more fabrics and soft furnishings than many do now, all of which tend to harbour fleas. Carpets or rugs were almost universal (few homes having wooden or bare floors) curtains were the norm and blinds uncommon, and lounge furniture would usually be fabric not leather, and often kept for a couple of decades.
Flea treating homes, then, was a challenge and often a losing battle; flea bombs and fairly heavy-duty chemicals that are not legal as a rule today were common, but had limited effect even then.
Our understanding of fleas, how they live, where they live, and what eradicates them – and safely – is very different today! Fortunately, homes are far less likely to develop infestations today, and easier to treat if they do; and fleas can be kept off dogs entirely with the right veterinary flea product.