I use Nexgard currently. But when I'm areas I know are bad for fleas and especially ticks, I take a flea comb to my dogs before getting in the car. Fair Hill MD is really bad and they have double stepped platforms to make it easy for people to get on their horses. I put my dogs on that and flea comb them out thoroughly to make sure I get any fleas or ticks off my dog and before they could potentially fall off in the car and find their way to me.
Just be careful not to fall for people telling to bathe your dog with dish soap, especially Dawn as they are hard grease cutters and can really wreck the dogs skin and coat but really the skin. It will kill fleas, but sometimes at the expense of the skin which then takes time to repair on it's own.
Better off using an all natural kill on contact flea shampoo like de fleas by natural chemistry
