Parvovirus

What is it

Parvovirus is an often-fatal viral disease. If not treated immediately, it will almost always lead to death. There are two main types of infections – cardiac (heart-related) and intestinal. It is possible for a dog to contract both infections at once. Cardiac infections cause breathing problems and heart failure, while intestinal infections attack the lining of the digestive system. This makes the dog unable to absorb nutrients or liquids. If not treated immediately, parvovirus will lead to dehydration, shock, and death.

Symptoms

Generally, dogs start displaying symptoms 7 to 10 days after infection.

Cardiac infection symptoms are breathing difficulties, followed by heart failure.

Early symptoms of intestinal infection are:

·       high fever

·       lethargy

·       depression

·       loss of appetite

Advanced symptoms are:

·         vomiting

·         severe, bloody diarrhoea. The diarrhoea is foul-smelling and may be yellowish in colour.

How it spreads

Parvovirus is highly contagious, and spreads through direct or indirect contact of feces. This includes oral contact with infected soil, or even infected objects such as rags and toys. It is also possible for other animals (such as birds or even humans) to come into contact with infected objects and pass the virus on. Pregnant dogs may also spread the infection to unborn puppies, even if they do not display the symptoms themselves.

Who it affects

Dogs of all ages can contract parvovirus, but puppies are especially susceptible. Dogs that have contracted parvovirus in the past are more likely to contract the disease again.

Vaccinations and prevention

Colostrum (milk produced by the mother immediately after giving birth) carries antibodies that help nursing puppies fight off diseases. However, puppies may not take in enough antibodies to be able to effectively ward off parvovirus. Therefore, it is important to vaccinate your dog against this disease.

It is important to note that it can be difficult to successfully vaccinate a puppy, since lingering antibodies from the colostrum could prevent an effective response against the vaccine. You will therefore need to give your puppy a series of vaccinations over a period of time, usually every 3 to 4 weeks when your puppy is between 6 to 20 weeks of age, or as recommended by your veterinarian.

Bleach is effective in killing parvovirus. A mixture of chlorine bleach and water (1 part bleach, 30 parts water) may be used to disinfect areas and objects that may be contaminated.

The ABCs of Tick Fever in Dogs

Tick fever, or tracker dog disease, is the common name for the disease, erhlichiosis. Tick fever affects dogs and in rare instances, humans. German shepherds and Doberman pinschers tend to be affected more severely by the disease. 

Tick fever is caused by bacteria carried by the brown dog tick, which passes the ehrlichia organism into a dog’s bloodstream when it bites. 

Red dog ticks

What are the Symptoms?

There are three stages of tick fever, each varying in severity:

1. The first (or acute) stage can lead to fever and blood disorders, which involve sudden nosebleeds or blood in the stool. An infected dog may also have trouble breathing, noticeably swollen lymph glands and coordination problems. Watch out for trembling and shivering, as well as dark-coloured urine and pale gums. Depending on the severity of infection, the dog will refuse food and be reluctant to leave his bed. This stage can happen anywhere from eight to 20 days after the tick has bitten the dog, and could last for up to a month. It is possible for a dog to be cured during this phase.

2. The second stage (or the subclinical phase) can last anything from two weeks up to five years if the tick fever eventually progresses to the chronic stage. This stage has no outward signs. Only blood tests can tell that the dog is still infected, as these blood tests will show if the bacteria are lingering in the dog's bloodstream. 

3. Unfortunately, the infected dog's immune system may be unable to eliminate the bacteria. The third and most serious stage of infection, the chronic phase, will then commence. The signs are similar to the initial symptoms, but come on far more severely. As compared to a nosebleed, the dog may bleed out of the nose or eyes. There is a danger of bleeding in the kidneys or bowels as well. The infected dog could also suffer from lameness, anaemia, and neurological disorders. Additional symptoms include ocular pain (uveitis), corneal oedema ("blue" eyes), retinal haemorrhages and detachment with blindness. Tick fever at this stage can be fatal, and a dog can die in a matter of days when chronic symptoms start.

What are the Remedies?

A definite diagnosis of tick fever can be difficult, since blood smears (taken from the ear or a toe) may not always show the parasite. As rapid treatment is the key to success, subject to the vets’ assessment, they may treat regardless of whether the parasite is found.

Treatment consists of antibiotics to kill the parasite. Vets may prescribe supportive therapy such as a drip or anti-vomiting drugs to supplement the treatment. There may also be other problems that need to be corrected such as anaemia or low platelet count (treated via blood or plasma transfusions) and breathing difficulties (treated via oxygen therapy). Other than that, lots of tender loving care to persuade your dog to recover is the most valuable medicine.

How to Prevent Tick Fever?

The only way to prevent tick fever is to ensure that your dog does not get bitten in the first place. This is accomplished by using anti-tick products that will repel or kill ticks. Such products include spot-on applications and anti-tick collars. Do also conduct rigorous checks on your dog after it has frolicked in the woods or high grass to be sure that ticks are not on its coat or body, and use anti-tick washes or shampoos as well. Focus on the armpits, groin, belly and in between toes. 

Heartworm Disease

HHHeartworm (Dirofilaria immitis) is a parasitic filarial worm that lives in the right side of the heart and adjacent blood vessels of infected dogs and (to a lesser extent) cats.

The disease is transmitted to mosquitoes and it is important to know that this parasite does occur in Singapore.

The adult worms can live for several years in the host and can block and damage the heart and blood vessels going to the lungs.

When the adult worms mature at about 6 months old, they produce live offspring called microfilariae – these small wriggly worms can be seen in the blood of infected dogs under the microscope.

The microfilariae are then transmitted via mosquitoes to another dog where they mature and migrate to the heart.

Dogs that are infected with heartworm disease show signs such as weight loss, anorexia, coughing, breathing problems and exercise intolerance depending on the severity of the infection. If left untreated, they eventually develop congestive heart failure and die.

Heartworm disease is more of a problem in certain districts in Singapore. We have observed that the areas more prone to this disease are: Katong, Changi, Bukit Timah, Woodlands, Yio Chu Kang, Seletar, Sembawang, Thomson and Upper Thomson next to the nature reserves.

Dogs living in landed properties are also more at risk. This ties in with greater incidence of mosquitoes around these residences. Furthermore, these dogs are more likely to be living outdoors.

Fortunately, heartworm disease is preventable. It is administered either with monthly oral tablets / chewables, or monthly topical solutions, or with an annual injection. It is recommended that puppies start on heartworm prevention from 4-6 months of age. Dogs above 6 months old require a blood test to ensure that they are disease free prior to starting on prevention. It can be dangerous to give prevention to an already infected dog.

Heartworm Test Kit

To test for heartworms, a small blood sample is collected and an ELISA test kit is performed for adult heartworms (above) and a small drop of blood is visualised under the microscope for juvenile heartworms (called microfilriae).

The dark blue spot on top is the control dot (to indicate that the test is performed correctly). The faint blue spot below on the right hand side indicates this dog is positive for adult heartworms.

In the instance that heartworm disease is detected, your veterinarian will be able to discuss with you the treatment options.

To Note:

-          Intestinal deworm tablets such as “all-wormers” do not prevent or treat heartworms.

-          Mosquitoes are required to spread the heartworm disease; therefore the dog does  
           not need to be directly in contact with other dogs to be infected.

By Dr Ang Yilin for Mount Pleasant Animal Medical Centre

Canine Vaccinations

CCGetting the right vaccinations for your dog is easy when you know how. Unfortunately, not all dog owners do. There are many myths and misconceptions regarding vaccinations, and this article will help dispel some of them.

Why vaccinate?

Singapore law requires all imported dogs be vaccinated. However, it is always a good idea to vaccinate your dog, imported or not. Like they say, "better safe than sorry". Getting your dog the right vaccinations could prevent illnesses that could lead to death.

How do vaccinations work?

Pet vaccinations work the same way as human vaccinations. A shot containing a tiny sample of a virus is given to your dog, which stimulates the immune system to create antibodies that combat the virus. For a period of time (called the immunity period), your dog’s immune system will then be able to recognize the virus if exposed to it, and produce the necessary antibodies to prevent your dog from falling sick.

Types of vaccines

There are 2 groups of vaccines: core and noncore. Every dog should receive core vaccines. Noncore vaccines, however, may not be necessary. Whether your dog needs a noncore vaccine depends on several factors, including age, breed and health status. Below is a list of common core and noncore vaccines.

Core vaccines:

- Distemper

- Canine Adenovirus-2 (hepatitis and respiratory disease)

- Canine Parvovirus-2

Noncore vaccines:

- Leptospirosis

- Canine Parainfluenza ("kennel cough")

- Bordetella Bronchiseptica ("kennel cough")

There are also 2 different types of vaccines against the same disease, modified live vaccines (MLVs) which are genetically modified living viruses, and killed viruses (inactive vaccines). MLVs take effect more quickly than killed vaccines, and provide immunity for a longer period. However, they are not suitable for pregnant or sick dogs. Killed vaccines are more stable, but require several shots to be effective and are more likely to cause side effects like fever, hives, facial swelling or vomiting and diarrhea. Before making a decision, ask your vet about the suitability of each type of vaccine for your dog.

Frequency of vaccinations & boosters

Contrary to popular belief, it is not necessary to bring your dog for booster shots or re-vaccinations annually. The length of immunity provided by each vaccine varies, and it is very important to pay attention to each vaccine's effective period. Draw up a chart for your dog's vaccination schedule to help you keep track of when you need to bring your dog for re-vaccination. Bringing your dog for vaccinations too frequently could harm your dog's health and immune system.

The AVA of Singapore does not have a recommended vaccination schedule.