Let's talk about why it isn't smart for your puppy to walk around PetSmart and other "high dog traffic" places and how you can avoid your puppy becoming sick from Parvo.
What is Parvo?
You've heard of the flu, right? You've obviously heard of COVID, right? But, have you heard of Parvo? Canine Parvovirus is a highly contagious disease that spreads through direct contact with an infected dog or by indirect contact with a contaminated object, like feces, shoes or toys. The Merck Veterinary Manual classifies the virus as- "a disease of the stomach and small intestines". The virus prefers to infect the small intestine and not only does it destroy cells but also impairs absorption and disrupts the gut barrier. It can even affect the heart in some, uncommon, cases. It is most common in puppies aged 6 weeks up to 6 months old. Puppy vaccinations do help prevent Parvo but do not guarantee your puppy against it 100%. Puppies are extremely vulnerable to Parvo until they have received all Veterinarian recommended shots. Do not think the shots at Tractor Supply are adequate. The handling of those vaccines from manufacturer to store and then to customer cannot be guaranteed. The vaccine may have gotten forgotten in the back of the store, or a customer decided they didn't need the shot and just put it back on a shelf somewhere. Someone, not knowing better, may stick it back in the fridge for purchase not knowing it is no longer viable and won't do your puppy any good. Establishing a relationship and routine visits to a licensed Veterinarian is your best method of having the correct and viable vaccines administered to your puppy.
How would my puppy get Parvo?
Now that you know what it is and what signs to look for, let's talk about how your puppy comes in contact with Parvo. Every time your puppy sniffs your shoes to investigate where you went that day, your puppy may be exposed to this virus. But how? Well, by indirect transmission. This can occur when you walk across someone's yard where an infected dog pooped and then you went home, took off your shoes and your puppy decided one of those sneakers looked like a fun chew toy. Indirect transmission can take place in a variety of ways. Any time your puppy encounters a contaminated object, such as a toy played with by an infected dog, or a tennis ball someone fetched who was infected. Food/water bowls, leashes, clothing, collars, toys, you get the point.
How do I know if my puppy is sick from Parvo?
First of all, if you have any suspicions at all, CALL YOUR VET!
Some of the signs of Parvo include: the most common bloody diarrhea, vomiting, foaming at the mouth, lethargic behavior, acting out of it and not aware of surroundings, weakness, dehydration and acting depressed. A puppy who is infected may not actually show signs for a couple days. So, at the first sign of Parvovirus, call your vet so you can get ahead of it. Typically, around day 4-5 of exposure, your puppy will start what's called "shedding" the virus which is where he will become contagious. Remember, saliva, poop, etc. are all means of virus transfer. The virus can live indoors for a month to two months and can live outside, in the right conditions, for many months, even up to a year. Be sure to talk to your Vet about how to decontaminate.
How can I socialize with Parvo around?
Socializing your puppy is an important step in your puppy becoming a good citizen in this world. In a litter, a puppy naturally begins socializing with it's brothers and sisters. However, once removed from the litter, it's vital the socialization process continue. But, how can this happen if you can't take your puppy outside for fear of Parvo? Rest assured, it is less likely that your puppy will become infected if you decide to safely socialize your puppy with fully vaccinated adult dogs in environments such as your home. While not highly recommended to join a group obedience class, most puppy classes require proof of vaccination for all of their participants but still be sure to ask. Also, always talk to your vet about concerns and what he/she recommends.
Lowes, Home Depot, and other dog friendly but not high traffic places may be good socializing environments. Until two weeks after the last round of puppy shots, I would advise you to take your puppy in the (disinfected) shopping cart. This will give him exposure in a safe manner and is less likely for Parvo exposure. Having friends over to your home is another great option for your puppy to be around unfamiliar faces. Just be sure they wash their hands and haven't been around any sick acting puppies or dogs lately. You may also ask them to take off their shoes before entering your home. Practicing leash work in the back yard is another good idea. Just use good judgement and always consult your Vet when needed.
A great resource for all things Puppy, check out AKC.org
They also have an educational article on Puppy Vaccines I recommend you read.