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Dog Vaccination Guide - DHP, L4, Kennel Cough?

Vaccinations are a vital part of your dog's life, they help prevent some really serious diseases. Read on to find out why you should consider them...



The newest addition to your family has finally arrived and now you need to start thinking about vaccinations. Vaccinations are imperative for the prevention of important infectious diseases that can cause a lot of harm to your pooch, but they can be a little daunting.

Keep reading our post for more information on what vaccinations your dog needs, when they need to get them and why. We will also answer some common questions such as:

  • What vaccinations does my puppy need?
  • Do vaccines hurt? 
  • Can I socialise my puppy before vaccinations?
  • What vaccinations does my dog need before travelling/kennels?


What is a Vaccine and How do they Work?

Vaccinations are a form of preventative medicine that protects against a number of quite scary viral and bacterial diseases. They are one of the most important contributors to a healthy and happy life for your dog. Additionally, a greater proportion of dogs vaccinated means less risk to the entire dog community!

A vaccination triggers your dog's immune system by delivering a modified or killed version of a bacteria or virus to their body. The version of bacteria/virus used in vaccines is entirely harmless, as it has had all the nasty disease-causing parts removed. This means that if your dog were to come into contact with the real deal, it will prevent them from developing potentially fatal disease and reduce spread to other dogs. They will need to be topped up with booster vaccinations to keep your dog's immunity effective. 


What to Expect at your Vaccine Appointment?

Many new owners have concerns when going in for their puppy's first vaccine appointment. Below are the answers to some common questions that can cause owners a bit of worry!


Where are they given?

Vaccinations are usually given by injection under a bit of loose skin - most commonly over your dog's back/neck (except for kennel cough - which we will get to in a bit!).


Does it Hurt?

Owners can often (and quite rightly) be concerned that the needle will hurt. We've all been told 'not to worry you'll just feel a sharp scratch' and it seems this is the same in dogs. A majority of adult dogs are completely un-phased by vaccine administration and usually don't even notice.

Puppies on the other hand are known to be a bit more dramatic. The first vaccine can be scary and they may get a bit upset by it all. Not to worry though - positive re-enforcement from both yourselves and the vet, along with a healthy number of treats to distract them, will have them coming round to it in no time. 


How Effective are they?

No vaccine is 100% effective, but it will provide the best chance for your dogs to avoid contracting these worrying diseases and if they were to be infected, it will help to dampen down clinical signs.


Are there Times when Vaccination is a Bad Idea?

Vaccinations need to be given when your dog is healthy. This is so their body can amount enough of an immune response to protect them against the disease.

At your vaccination appointment, your veterinary surgeon will ask a few screening questions and do a general clinical exam to make sure your dog is fit for vaccination. If your dog has been unwell, it is likely that it will have to be postponed until they are feeling better. 


Are there any Side Effects of Vaccinations?

Adverse effects to injectable vaccines are very rare. The most common of these are lethargy and generally looking a bit sorry for themselves. This is because your dog's body is working hard to mount an immune response, which takes a lot of energy.

They may also have a bit of muscle pain and feel a bit sore, especially over the site, and you may see or feel a lump at the site the vaccine was given. This should fade over time, but if it persists longer than a few weeks we would recommend having a chat to your veterinary surgeon. 

More serious, but rarer vaccine reactions include anaphylaxis, infection and abscessation at the vaccine site. Anaphylaxis is characterised by hives, itchiness, facial swelling, vomiting and diarrhoea and would occur shortly after injection. While extremely rare, if you are worried about an anaphylaxis reaction you can use our Felcana Symptom Checker to find out if your dog needs emergency veterinary care.


What can my Dog be Vaccinated Against? 

Core Vaccines 

Core Vaccinations are those that all dogs need to receive regardless of their circumstances. They are so important to prevent your dog getting sick and reduces disease threats to the rest of the canine population -  by contributing to herd immunity. So, vaccinating your dog not only helps protect them but also all their friends. The core vaccines in the UK are against:

  • Canine Distemper Virus
  • Infectious Canine Hepatitis
  • Canine Parvovirus
  • Leptospirosis


1. DHP 

DHP is a combination vaccine that covers  the viral diseases Distemper, Infectious Hepatitis and Parvovirus all in one. 

Canine Distemper Virus attacks the dog's lymphoid system. It causes fever, vomiting, diarrhoea, coughing, discharge from the nose and eyes and neurological signs including seizures. There are no effective treatments for distemper and while recovery is possible, it more often than not has a much less favourable outcome. All in all, it’s definitely a disease best avoided. 

Infectious Canine Hepatitis is very contagious and can survive in the environment and on objects for months. This means infection can happen from contact with saliva, urine, faeces and indirectly through contact with things that have the virus on them. It infects the cells of the liver and causes widespread damage to tissues. Clinical signs include fever, lethargy, inappetence, vomiting, diarrhoea and an increased breathing rate. Again, there is no treatment available and if your dog were to get infected with this virus it can cause long term damage to the liver and kidneys - were they to survive. 

Canine parvovirus is a virus that can infect all ages of dogs by inhalation or ingestion and survives very well in the environment. It causes a drop in white blood cells and damages the intestines, leading to the clinical signs of fever, diarrhoea (usually bloody), vomiting and possibly death. There is no specific treatment available, making prevention with the vaccine your best bet.


2. Leptospirosis 

Leptospirosis is a bacterial infection that causes damage to the liver and kidneys. It is passed through urine and clinical signs include lethargy, inappetence, vomiting, diarrhoea, fever and jaundice (yellow discolouration to the whites of the eyes, gums and skin.) While treatment is available with antibiotics, prevention is a much better way of tackling the disease - especially as it has the potential to spread to humans.

What Leptospirosis Vaccine is Best?

There are many different strains of leptospirosis and there are two different vaccinations that protect against the different strains. These are L2 and L4 vaccines. L2 and L4 both provide protection against the two most common strains found in the UK.

L4 provides protection to additional strains which are mainly found in mainland Europe but have been reported to cause disease in the UK sporadically. The actual distribution of strains in the UK is not completely understood, so the importance of the additional protection provided by the L4 as opposed to the L2 vaccine is up for debate. 


Non-Core Vaccines 

Non-core vaccines are administered on a case-by-case basis to those dogs most at risk - with risk being associated with geographical location, the local environment and lifestyle factors. Whether or not your dog needs non-core vaccines can be discussed at your annual health examination with your vet and administered accordingly. 


1. Kennel Cough 

Kennel Cough is a disease caused by a mixture of bacteria and viruses. While it is usually a mild and self-limiting respiratory infection, there are times when owners may opt or must get it for their dogs. 

It presents as a hacking cough that can last weeks. Often this self-resolves with minimal treatment but occasionally it can lead to pneumonia. If your dog shows clinical signs, they should be kept away from other dogs and public spaces while they are showing symptoms to reduce transmission.

This disease is prevalent in some areas in the UK and many people prefer to get their dogs vaccinated against it. It is a common necessity of most boarding kennels or doggy day cares and it is strongly recommended if your dog is likely to mix with others (including at dog parks or out on walks) to prevent a disease outbreak - as it is very infectious. Usually, boarding kennels require vaccination at least one week before your dog is going to board.

The kennel cough vaccine is like the human flu vaccine, in that it doesn't prevent infection but reduces the severity of illness - allowing your dog's body to fight the disease faster and more effectively. 

The vaccine is squirted up the nose from a syringe and your dog will lick it off - which is great because it is also effective when administered orally!

Occasionally a mild form of kennel cough may develop 2-7 days after the vaccine as a side effect and will resolve by itself.

We recommend having a chat with your vet to decide if your dog is a good contender for this vaccine.

Take a look at our blogs regarding the oral kennel cough vaccination, and answers to questions such as can I walk my dog with kennel cough, or what disinfectants can I use to target kennel cough?

*A Note for Immunocompromised Owners*

The bacterial part of Kennel Cough (Bordetella bronchiseptica) has the potential (but it is extremely uncommon) to infect immunocompromised owners. While there is some infective potential as it is a modified live vaccine, the risk of infection is greater (albeit a very low risk overall) from your dog having kennel cough than your dog receiving the kennel cough vaccine. The pros and cons need to be weighed up and you should chat to your GP about this and your personal risk.


Travel Vaccinations 

Many owners travel with their dogs and while there is no reason for your dog to miss out on the family holiday, there are some steps that need to be taken to ensure they can travel. One of those is additional vaccines.


1. Rabies Vaccine 

Most of us have heard of rabies and it is inevitably fatal with the potential to transmit to humans - as it is a zoonotic disease. Thankfully, the UK has been Rabies free for quite some time. However, this can't be said for many other countries, which is why a Rabies vaccination is required for dogs travelling to and from the UK.

There are a few specifics that need to be met for a Rabies vaccine to be valid for travel: 

  • Your dog must be microchipped before receiving the vaccination
  • Your dog must be at least 12 weeks of age
  • The vaccination is only valid after 21 days from administration for travel to Europe and Northern Ireland - travel will not be possible before this
  • The rabies vaccination is valid for 3 years from the administration if given in the UK

The Rabies vaccine has the same potential side effects as any injectable vaccine, which have been discussed previously in this post.

Travel requirements vary from country to country and it's not uncommon for them to change suddenly. The information provided here is accurate up to the 14/05/2022. Check with your Vet and/or the DEFRA Pet Travel Scheme for up-to-date information on what is required. We would recommend ringing your vets up well in advance if you're planning to travel with your dog.

Other vaccinations, such as the Leishmania vaccine, may be required by certain countries. 


Puppy Vaccination Schedules


Primary Vaccination Course

The primary vaccination course for a puppy's core vaccines must happen at specific times. When your puppy is first born, it is protected from disease by antibodies from its mother. The number of these antibodies start to decrease at around 8-12 weeks old, making them more susceptible to disease.

As the rate at which immunity from the mother wanes is variable, multiple vaccination doses are given to ensure your puppy stays fully protected. The official recommendations state that:

  • Initial vaccination should be given at 6-8 weeks (but they can be started as early as 4 weeks).
  • Subsequent doses should be given at 2–4 week intervals until the puppy is 16 weeks old.
  • A booster vaccination should then be given at 12 months.

However, given the importance of socialisation for dogs, many practices adopt a shortened schedule. Three doses are given - starting around 8 weeks and ending at around 13 weeks - followed by a booster at 12 months. The 12-month booster is really important in ensuring good immunity as it acts as an insurance dose in case any of the vaccinations from the primary course happened to fail.



Following completion of the primary vaccination course and the 12-month booster, your dog will require regular vaccination to maintain protection against infectious disease.

The DHP vaccine is a modified live vaccine which just means that after the primary course, your dog will only need a booster every 3 years - as it provides a stronger immunity to these diseases. 

The Leptospirosis vaccination is a killed vaccine, meaning immunity levels wane faster than with the DHP vaccine. Therefore, Leptospirosis needs to be boosted with an annual vaccination.

If you decide annual boosters don't suit your pet there are other options available - such as titre testing for DHP. A blood sample is taken and the level of protection your dog has against Distemper, Parvovirus and Infectious Hepatitis can be assessed. If the titre level is too low for adequate immunity, a booster will need to be given. Titre testing is not available for Leptospirosis.


Remember that Prevention is the Best Medicine!

Vaccinations are the most effective way to protect your dog against deadly diseases and reduce infections throughout the dog population, but a primary course is not enough! Refer to the vaccination record given to you by your vet to stay on top of your dog's boosters and chat to your vet if any concerns come up.

There's nothing better than prevention for your dog's health!


This article was written by Sumuduni Theminimulle. Sumuduni is a final year vet student at the University of Bristol. She is set to graduate in 2022 and start her first role as a small animal vet in Essex.