A puppy should have its first vaccination between 6 and 9 weeks old. This means that a puppy has usually had its first vaccination with the breeder before you take it home. If not, then it’s advisable to take your new puppy to the vets within a day or two for a full examination and to start their vaccination course as recommended by your veterinary surgeon. Very tiny puppies, or puppies that are not well may have their vaccinations delayed according to the vet’s advice.  

Older dogs, or rescue dogs with no vaccination history can have their first vaccination at any time providing they are fit and well. The vet will always do a full examination before vaccinating your dog to make sure that your pet is well enough to be vaccinated. 

Depending on the vaccine being used, the second vaccination is given between 2 and 4 weeks after the first. If there are health concerns, or the dog is of a breed that is known to have immune systems that develop later, then a third vaccination after another 2-4 weeks may be advised to ensure that the dog has full cover against the diseases included in the vaccine.  

 Puppies that were a bit weaker and not growing so well in early life may be advised to have a third vaccination. Your veterinary surgeon will decide on the vaccine plan at the time of each vaccination. 

Generally, all puppies need a course of two injections. The first is at 6-9 weeks old, with a second 2-4 weeks later. Sometimes a third vaccination is advised. The first booster is given 1 year after the puppy course and is considered part of that puppy course.  

After that yearly boosters are required for some parts of the vaccine, other parts can be given less frequently. Your vet will advise on their vaccination programme as this depends partly on the risk within your local area. 

Vaccines are effective for long periods of time, but the effectiveness reduces as time goes on. The timings of the booster vaccination are designed to refresh the immune memory at a time before the level of effectiveness has dropped too much and the dog is at risk of catching that disease. Some vaccines (Leptospira, Kennel Cough) are relatively short lasting and so need yearly boosters. Some others, such as Rabies (if given in the UK) and DHP (Distemper, Hepatitis and Parvo) can have boosters every 3 years, depending on the brand. You will be advised on the most appropriate vaccine course for your dog. 

Vaccinations can be delayed for many reasons and there can be some leeway with booster vaccinations. Very small or weaker puppies and puppies or adult dogs that are unwell, may have their vaccinations delayed on veterinary advice. If the dog’s immune system is fighting an infection or there is an underlying disease that is not being treated, then the immune system cannot react normally to the vaccination and the dog will not get enough cover.  

Dogs that are unwell with longer term conditions may need investigation, diagnosis and treatment to stabilise the dog before vaccination is given. Dogs on treatment who are stable with long term conditions, such as Diabetes, Hypothyroidism or Cushings, can have their vaccinations as normal.  

External factors may also be a factor. For example, Covid delayed many vaccinations as vets were not allowed to do them during lockdowns. But sometimes family emergencies, busy lifestyles, holidays and just simply forgetting may also mean that vaccinations get delayed. To help avoid this as much as possible, your vet usually sends a reminder by text or email when your dog’s vaccination is due. 

If the delay is for the second injection, then often a third vaccination will be advised even if the delay is short. This is because timing is quite crucial for these two vaccines. The first adult booster should be given on time, as that builds on the immunity derived from the puppy course. Normally, adult boosters may be delayed a little if necessary, and your vet can advise on the best plan of action if a delay has or is likely to happen. 

Ideally, vaccinations should be given as near to the due date as possible to ensure a good immune response to the diseases covered, so if there has been a delay contact your vet straight away for advice. 

Core vaccines are advised for every dog. The diseases covered by these vaccinations cause severe illness and are difficult to treat, with a high level of mortality. In the UK these include: 

• Distemper: a viral disease that spreads readily via contact with body fluids and affects multiple organs in the body. Animals affected by this disease often pass away, but those that survive may develop lifelong complications including neurological degeneration 
• Infectious Hepatitis/Adenovirus: adenovirus 1 affects the liver, kidneys, lungs, blood vessels and the eyes. Transmission is through contact with body fluids and mortality rate is up to 30%. The vaccine also covers Adenovirus 2, which causes respiratory disease 
• Parvovirus: a highly contagious viral disease, causing severe gastroenteritis. If untreated, mortality is 80-90% in puppies. Transmission is by contact with an infected dog, it’s faeces or surroundings. This bug can last for an extended period in the environment despite use of cleaning products. 
• Leptospirosis: a bacterial disease caught by contact with rodent urine in the environment. The disease is transmissible to humans, so puts owners and others in the household at risk. The liver and kidneys are mainly affected, and, if the pet survives, recovery can take weeks of hospitalised care.  

Other vaccines are available for dogs at risk of infection: 

• Kennel Cough vaccine (Bordetella bronchiseptica with Canine Parainfluenza Virus): given to dogs who work, socialise or go into kennels or doggy daycare. Easily spread by contact with infected dogs and their surroundings. Kennel cough not only causes coughing, but can make the dog very unwell and recovery can take weeks. The combined vaccine is given yearly up the nose or into the mouth depending on the vaccine type 
• Rabies: a viral disease that affects the nervous system and is transmissible to humans. It is spread in saliva and is normally fatal in dogs. Rabies is not present in the UK, but any dogs that travel abroad must be rabies vaccinated 
• Herpes virus causes abortion, stillbirth and infertility in breeding bitches and early death in new-born puppies. Two vaccinations are needed each breeding cycle, and your vet will advise on timings 

Vaccines contain either live, modified live, inactivated or part of the organism that causes the disease that is covered. The vaccine is designed so it doesn’t cause the disease in the dog but triggers an immune response to the organism. The dog develops antibodies that can remember the organism and they provide a fast response should the dog encounter the disease later in life, preventing disease development. 

The tiny amount of organism present in the vaccine do not trigger sufficient immune reaction on its own, so it is mixed with a compound that triggers inflammation to ensure a better immune response.  

The vaccine itself is only present in the dog for a short period of time, but the immune response it generates lasts much longer. 

The vaccine itself can rarely cause an allergic response at the time of vaccination, but there is no evidence to say that being vaccinated causes allergies. The tendency for allergy is in the individual puppy or dog and is already there if the dog has a reaction to the vaccine. The exact causes of allergies in dogs are not known, lifelong allergic conditions do not usually develop until the dog is 6 months old, when the immune system is fully developed, and get worse as the dog ages. Some puppies react adversely to the first vaccines but have no reaction at all when they are older, when the immune system has fully developed. 

Reactions are generally seen on the same day as vaccination. An allergic vaccine reaction that causes facial and/or paw swelling, hives and/or vomiting and diarrhoea need urgent treatment, as they can be part of an anaphylactic reaction. If this sort of reaction happens (there are only a few of these in every 10,000 vaccinated dogs) then your vet will give you advice on planning future vaccinations to make it safer for your dog. 

Small breed puppies can suffer from a drop in their blood glucose when stressed or excited, and a visit to the vets causes both. It is advisable to feed small amounts of food often around the vaccination time to avoid the lethargy and weakness associated with a low blood glucose. 

The physical examination and questions asked by the vet during the vaccination consultation are to check the puppy or dog is well enough to be vaccinated and helps to keep reactions low by not vaccinating animals at risk. Travelling in the car, going into the vets, being handled and examined are all stressful to the animal, especially a puppy or nervous dog, so any underlying conditions, such as gastro-enteritis, may be triggered by that alone.  

The core vaccinations are not mandatory by law but are strongly advised to reduce the level of infection in the dog population as a whole, to improve the health of the individual animal and to protect humans against the transmissible diseases, such as Leptospirosis (Weil’s disease). 

Rabies vaccination is the only mandatory vaccination for dogs that are travelling abroad or being exported. For European travel it must be given at least 21 days before the date of travel, and you will also need an Animal Health Certificate (AHC) Your vet will give you guidance on how to travel abroad or export your dog. Imported dogs must be vaccinated against rabies before coming into the UK. 

The cost of vaccination depends on whether it is a full course or a booster. The full course is often priced so that paying for the two vaccinations at the first appointment is cheaper than paying for the two separately. A third vaccination (if advised) is not always covered in the full course price. Vet practices now offer preventive health plans that are a monthly payment to cover core vaccinations and all flea and worm treatments and works out cheaper than paying for them separately. Your vet practice can give you information about their plan.