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There are a wide variety of worms that can infect your dog. Although many of the symptoms are similar, each will require a specific type of medication for treatment. When an inappropriate medication is used to treat worms, infestations can return or worsen in severity, causing additional medical complications. Some of the worms that commonly affect dogs include: heartworms, roundworms, tapeworms, hookworms, and whipworms.
worms in dogs: A Disclaimer
The information below is designed to inform you about these parasites and not to diagnose or treat your dog. Any time you suspect that your dog may have any parasitic infection, a veterinary diagnosis is mandatory in order to give your dog the most effective treatment for their condition.
The biggest problem for dog owners in terms of non-intestinal worms in dogs is heartworms. In recent years awareness of heartworms has risen and resulted in increased preventative efforts by pet owners throughout the United States.
Heartworms are a parasite that is contracted through bites from infected mosquitoes. As these mosquitoes bite dogs they transmit heartworm larvae in to the dog’s bloodstream. The heartworm eggs travel to the dog’s heart where they settle in the right heart ventricle and begin to duplicate. As these worms increase in number and grow larger they soon begin to cause severe damage to the dog’s heart, lungs and other major organs. Heartworms can live as long as five years within a dog but the infestation usually becomes fatal before that point. Heartworm infection is most commonly diagnosed by taking blood samples and testing them for the presence of heartworm offspring.
Spotting and Treating Heartworms
Early signs of heartworm infection can be easy to miss and as a result it is often not until the infection becomes severe that it is caught. Some of the most common signs of dogs suffering heartworms include: hair loss, jaundice, diarrhea, respiratory trouble, wheezing, loss of appetite, blindness, increased heartbeat, vomiting, poor coat, coughing, lethargy and weight loss. Treatment for heartworm infestation is dangerous and since most cases are not caught until dogs exhibit symptoms due to organ damage, treatment can often be fatal. Treatment involves injecting toxins in to the bloodstream that will kill the heartworms; however, they can also prove fatal to weakened dogs. The sooner heartworm infestations are caught, the better the chance that a dog will survive treatment because there will be less damage to major organs. Heartworm treatment is expensive and time consuming. Numerous treatments are required to eliminate infestations and throughout the numerous treatments the dog must be kept confined and inactive. In some cases where heartworm infestations are severe and dogs are too disabled from their condition, veterinarians may suggest forgoing treatment and opting for euthanization. Choosing euthanization may be a difficult decision to make, but the amount of discomfort a dog experiences during advanced stages of heartworm infection is significant.
Preventing heartworms is easy with the large number of heartworm tablets available for monthly dosage. The different heartworm preventative medications vary in price and all are more affordable than a single heart worm treatment. Some of the most commonly used heartworm preventative medications include: Heartgard Plus, Iverhart Plus and Panacur–C.
Interceptor and Sentinel are Not Available at This Time
Currently, Novartis has stopped production on many popular heartworm prevention meds (Interceptor and Sentinel) due to plant closing. Novartis claims that there is no problem with either of the products but there may be an issue with the plant that manufactures them along with several human meds (Gas-X, Excedrine, NoDoz). Two years later they are still not making these products so we have moved on. We recommend HeartGuard or Iverhart for sound preventative heartworm care for your dog.
Important Things to Keep in Mind about Heartworms:
- It is estimated that 100% of dogs exposed to infective heartworm larvae become infected with heartworms.
- According to the American Heartworm Society, only 55% of dogs in the United States are on heartworm preventative.
- “Indoor only” animals can also become infected with heartworms.
- More than thirty different animal species can contract heartworms including: wild canids, wild felids, sea lions and humans.
- Heart worm disease could be completely eliminated in domesticated animals if every pet owner administered heartworm preventative to their pet.
When referring to worms in general, most commonly people are referring to intestinal worms. These types of worms are found in the gastrointestinal tract of dogs where they thrive and reproduce, causing a slew of medical side effects. Intestinal worms are referred to as parasites because they attach to your dog’s intestinal wall and feed by leaching your dog’s nutrients. If left untreated, infestations of intestinal worms can become deadly by causing intestinal blockage. Dogs should be tested for intestinal parasites through the taking of a fecal sample once a year. All puppies should be issued de-wormers to ensure that they are not carrying worms or worm larvae. Most of the large name heartworm medications sold these days also provide protection against a number of the most common intestinal worm varieties to ensure that fully grown dogs are protected.
Roundworms are a particularly common type of parasitic worm found in young puppies. The majority of puppies have traces of roundworms or roundworm eggs in their tissue at birth as a result of migrating parasites from the mother’s tissue. Puppies can also contract roundworms from their mother’s milk. This is one of the reasons why puppies are de-wormed as soon as they are seen by a vet and given their initial “puppy shots.” Many breeders also take the precaution of administering de-wormer to ensure that their puppies remain healthy. Once within the dog’s body, the roundworms will travel to the intestinal tract where they will attach themselves to the intestinal wall and continue to grow. Some roundworms can grow as large as five inches long. Once roundworms reach sexual maturity they will begin shedding eggs within the dog’s small intestine. Infected dogs will pass roundworm eggs in their feces and the eggs can then go on to re-infect other dogs that are exposed to the infected feces. Once dogs become infected by ingesting the roundworm eggs (these eggs can survive in soil for years,) the eggs will hatch and young roundworms will travel to the lungs. Eventually these small larvae are coughed out of the lungs and swallowed where they will make their way to the small intestine to grow to full sized worms. It is easy to see how an untreated infection of roundworms can continue a cycle of infection among a neighborhood or kennel of dogs.
Spotting and Treating Roundworms
Dogs with an active case of roundworms can appear to have a bloated stomach and exhibit poor growth despite eating regularly. Infected dogs may also vomit or have diarrhea, cough, develop pneumonia or show signs of anemia. Owners may spot worms in their dogs vomit or feces. These worms can infect both young and old dogs and can become fatal by causing intestinal blockage if they are not treated as soon as possible. Roundworms are treated with a de-wormer, but it should be noted that this treatment is only effective for fully grown worms living in a dog’s intestinal tract, not for eggs. It is important to administer a full course of de-wormer prescribed for roundworms by a vet in order to ensure that the infestation is completely eradicated. The most commonly prescribed medications for roundworm infestations include: Sentinel, Drontal Plus, Panacur – C, Heartguard Plus, Worm X, Iverhart Plus and Interceptor.
Preventing roundworms in most dogs is as easy as keeping dogs away from other dog feces and administering a heartworm preventative that also protects against roundworms.
Tapeworms can be contracted through eating animals that are already infected with tapeworms or through eating fleas that feed on tapeworm eggs. Tapeworms appear as segmented and can be composed of as many as ninety different attached segments reaching as long as six inches in total length. Tapeworms live within the dogs intestines and absorb nutrients from the digestive tract through its skin. Like most other intestinal worms, tapeworms attach to the intestinal wall with their heads, though these worms utilize “suckers” to attach to the tissue. Amazingly, each section of the tapeworm has the ability to reproduce and contains eggs, which means that each section that breaks off the end of the worm releases eggs. As these eggs are released, they are passed in the dogs feces. This is often where the tapeworm eggs are ingested by fleas and the cycle begins again when that flea is ingested by another (or the same) dog. As the tapeworm grows, the end segments of the worm’s body will detach and the containing eggs and sections are excreted. Most pet owners are able to identify the presence of tapeworms by spotting these small rice like segments (which are often still moving) in their dog’s fur near their anus. Tapeworms can be spread from dogs to humans.
Spotting and Treating Tapeworms
Dogs with a tapeworm infestation may appear with no symptoms at all, or they may appear with a number of general intestinal type symptoms. Some of the more general symptoms include: itching around the anus, vomiting, an upset stomach, diarrhea and abdominal discomfort. Tapeworm infestations may also present with convulsions in extreme cases. Tapeworms in dogs are most commonly treated with Drontal Plus, Panacur – C and Tapeworm tabs. Tapeworm infestations in humans are most commonly treated with Praziquantel.
Unlike many other worms, tapeworms are not treated with heartworm medications that also cover parasitic worms. Tapeworms can be prevented by applying flea preventative regularly. Rodent populations should also be controlled since they can lead to an increase in fleas which feed on tapeworm eggs.
Hookworms are very small worms that are named because of their hook-like teeth that they use to attach to the intestinal lining. These worms feed upon their host animal’s blood and are the most common parasitic worm found in dogs. Hookworms can be contracted in the same methods as roundworms, particularly during the puppy life stage. Veterinarians believe that 20% of the pets in the United States are infected with hookworms. It is possible for humans to contract hookworms from their dogs. Hookworms are much like other parasitic worms in that they lay eggs in the intestinal tract of dogs and those eggs are then expelled in feces or through a mother dog’s tissues during pregnancy. Hookworm infestations are particularly devastating to young and elderly dogs and should be treated as soon as a vet identifies hookworm eggs in a fecal sample.
Spotting and Treating Hookworms
Dogs that have severe hookworm infections can often succumb to the parasite if not treated promptly. Signs of a hookworm infestation include: poor stamina, poor weight maintenance, progressive overall weakness, anemia, bloody diarrhea and an unwillingness to feed. In humans hookworm infestations can present with muscle pain, skin rashes and potentially lung disease. Commonly used hookworm medications for dogs include: Sentinel, Drontal Plus, Panacur – C, Heartguard Plus, Worm X, Iverhart plus and Interceptor. In humans the most commonly used medications for treatment are benzimidazoles.
Hookworms can be prevented with a number of heartworm preventative medications that also treat parasites. These worms can also be prevented by ensuring that your dog’s environment is kept clean.
Whipworms are so named because they have the appearance of a whip with one end thicker than the other, the thinner end having the appearance of a piece of thread. This type of parasitic worm lives in the first section of the dog’s large intestines – the cecum. Where roundworm females are capable of producing 200,000 eggs in a single day, whipworms produce much fewer eggs making detection of an infection much more difficult. Even with the administration of a fecal sample, a veterinarian may miss an infection. In cases where dogs exhibit clear symptoms of whipworm infestation, but a fecal test comes up negative, additional fecal samples may be required. Unlike roundworms, whipworms rarely cause fatal infections in dogs but they can lead to complications in infected dogs. Whipworms bury their heads in to the wall of the dog’s large intestine and feed on the dog’s blood. Once established in the dog’s intestines whipworms will lay their eggs that will be excreted in the dogs feces. Whipworm eggs are extremely difficult to eradicate from soil and can only effectively be destroyed by replacing soil. Even picking up feces can leave traces of whipworm eggs behind leaving other dogs susceptible for infection. Whipworms are one of the few parasitic worms that cannot be transmitted to humans from dogs.
Spotting and Treating Whipworms
Dogs with whipworms can show with a variety of symptoms including signs of anemia, diarrhea, hemorrhaging, weight loss and general upset stomach. If a case of whipworms is confirmed, all feces should be picked up and disposed of properly and soil should be replaced in order to avoid re-infection. Commonly used medications for whipworm infections include: Sentinel, Drontal Plus, Panacur – C and Interceptor.
Preventing whipworms should be done with a preventative oral medication. Interceptor is currently one of the few heartworm preventative medications that treats for whipworms as well as heartworms.
Not Only Your Dogs Are At Risk for Parasitic Worm Infections
All of the parasitic worms listed above have the potential to infect other household pets, wild animals and humans. While not all of these worms can be contracted from canine to human contact, the majority of them can be, which means that you need to be vigilant not only for your animals but for yourself as well. There are a number of ways that you can help to ensure that you are not exposed to these parasites:
- Avoiding contact with animals known to be infected with roundworm.
- Maintain a clean home and always pick up dog feces immediately.
- Always keep pets on regular preventative medications and get them tested regularly for parasites.
- Always wash your hands thoroughly after picking up waste, petting stranger’s dogs or dogs known to be infected. It is also advised to wash your hands after petting your own dog, particularly if they have been petted close to their rear end.
- Don’t walk barefoot on grass that could have been exposed to infected feces. It is generally a good idea not to walk barefoot on any public grassy areas since they could have been infected with parasites like hookworms.
- Keep pets regularly groomed to avoid any fecal matter from being caught in fur where it can expose you to infectious parasites.
The General Cost of Keeping a Healthy Dog
While it may sound expensive to keep a dog on so many preventatives, there are a small number of medications available that treat for all of these parasites with the exception of tapeworms. Tapeworms are not as significant of a problem as many other types of parasitic worms which is why they are generally not treated for in “all in one” medications. Two of the most popular medications that are used to prevent parasites on a monthly basis are Sentinel and Interceptor. The cost of these medications varies but can usually be purchased online for around $7.50 per pill for a twelve month supply for dogs 51 to 100 pounds. The cost of preventative medications is lower for animals that weigh less costing around $4.42 per pill for a twelve month supply for dogs 11 to 25 lbs. In addition to this medication a flea and tick preventative should be applied to prevent the transmission of parasites through fleas.
The average cost of flea and tick preventative also varies but averages to around $5 per month. A combined cost of less than $20 a month is much less than the cost of treating for parasitic infection and the damage that these infections cause. If you are a prospective dog owner and you cannot afford to administer monthly preventative medications, you should reconsider your desire for a dog.
Other Intestinal Parasites to Consider
There are a number of other intestinal parasites that can affect dogs that are commonly confused with the various worms already mentioned due to a similarity in symptoms. Below we will take a look at these parasites.
Coccidiosis is a parasitic infection that is caused by coccidium bacteria. This bacterium is spread through feces of infected dogs and is most commonly found in puppies that have developed the disease after exposure to infected adult dog’s feces. Like many intestinal parasites, coccidiosis can be particularly dangerous to young puppies with under-developed immune systems. Adult dogs can also be affected by this infection particularly when undergoing periods of stress such as traveling, moving and even weather changes.
Spotting and Treating Coccidia
Dogs infected with the Coccidia bacteria will present with watery and mucous like diarrhea. If the infection becomes severe diarrhea may be bloody and the dog may also present with symptoms of severe dehydration and overall weakness and lethargy.
Whenever any of these symptoms are noted it is crucial to get your dog to the vet regardless of their age because symptoms can escalate particularly quickly. The most common test performed by veterinarians that suspect coccidiosis is a fecal examination. In cases of coccidiosis the coccidium parasite is easily visible under the microscope. The parasite has an appearance somewhat like an eye with a pupil.
After confirming that coccidiosis is the cause of infection, your veterinarian will assess your dogs overall health. If your dog is experiencing significant distress due to dehydration and weakness they will keep your dog for inpatient treatment to administer fluids as well as medications to kill the parasite. If your dog is in overall good health your vet will send you home with medication to treat the parasite and suggest administering unflavored Pedialyte and plenty of water to keep your dog hydrated. Two weeks following completion of medication your vet will request a follow up fecal test to ensure that the parasite is no longer present.
The most commonly prescribed medications for coccidiosis infestations include: Albon®, Bactrovet®, or Tribrissen®.
The best way to prevent the spread of coccidiosis is to keep infected animals apart from other animals in the home and to ensure infected animals are treated completely. It is also important to test feces of pregnant bitches to ensure that they newborn puppies are protected from infection. Many people will also test young puppies to ensure they are not infected with coccidiosis after their birth.
Coccidiosis is yet another reason why it is important to always pick up after your dog since leaving your dogs infected feces can pass the disease on to other dogs!
Infection with the guardian parasite is referred to as giardiasis. Giardia is a protozoan parasite that is ingested by dogs when infectious cysts are shed in infected dog’s feces. Dogs can ingest these cysts through both direct and indirect contact with them and once ingested they travel down to the dogs intestinal tract. Many dogs ingest giardia cysts through water contamination which is why new puppy owners are advised against letting their dogs near local lakes and water bodies that could house the parasite.
It is important to note that giardia is the most common intestinal parasite found in the human digestive tract. It is possible for giardia to be passed on from dogs to humans so proper handling of infected dogs and infected feces is crucial.
Approximately 50% of puppies will develop a case of giardiasis and close to 100% of dogs that are confined in a kennel environment will contract the parasite. The reason for such a high incidence of this disease in confined dogs is the close proximity of dogs to each other and the ease of exposure.
Spotting and Treating Giardia
Spotting giardia in adult dogs can be trickier than with younger dogs since the disease tends to accelerate rather rapidly in younger dogs with less developed immune systems. The most significant symptom of giardia is diarrhea that may be greasy or frothy in appearance and have mucous in it. Feces from dogs with giardia also tend to have a particularly strong odor. If your dog exhibits any of these symptoms it is crucial to get them veterinary care in order to avoid dehydration, particularly in the case of very young puppies.
If your veterinarian suspects that your dog is suffering from giardiasis they will take a fecal sample. A fecal sample is taken not only to confirm the presence of the giardia parasite but also to rule out any other potential cause for symptoms such as maldigestion and malabsorption. The giardia parasite is a teardrop shaped parasite that can be seen in a fecal smear under a microscope.
After confirming that giardia parasites are present, your veterinarian will decide whether or not your dog needs to be kept in for observation or whether they can be released for treatment. You vet may also opt to administer fluids and then send you home to administer medication at home. In addition to prescription medication, veterinarians recommend bathing infected dogs to prevent any recontamination from remaining parasites on the dog. Once medication has been completed veterinarians will request a second fecal exam to ensure that the parasite has been eradicated completely. This step is particularly crucial since an ongoing giardia infection can have devastating effects on a dog and can even result in the death of young puppies in a relatively short time period.
The most commonly prescribed medications for giardia infections include: Flagyl also known as Metronidazole, Panacur and Valbazen. The favored of these is Flagyl however it is contraindicated in pregnancy.
Giardia is a particularly common parasite and it can be difficult to avoid; however, there are some tips to reduce the risk of your dog contracting it. Make sure not to take young dogs to water bodies where the parasite could be present and ensure that no dog drinks from the water or licks their paws after stepping in the water. Also ensure that whenever boarding your dog, you pick a kennel that offers individual spaces for dogs rather than communal kennel areas where the parasite can quickly spread.