Important Considerations
Last week, we discussed the more salient aspects of the worm burden associated with dogs and cats. We will now embark on the eradication of the worms and the treatment of the ailments/symptoms that develop with worm infestation.
There are some important considerations that the caregiver should note, before we address the actual treatment/eradication of worms.
1. Worms that infest the gastrointestinal (GI) tract (stomach and intestines) are not all of the same species. Hence, specific treatment regimens with different drugs and dosage rates are needed to eradicate specific worms.
2. Moreover, the worms infesting the GI tract reside in different areas of the gut. Stomach worms, of course, reside in the stomach. Tapeworms are quite different from stomach worms; they have segmented bodies and belong to a different family. Heartworms, because of their actions, complexity, and lethalness, will be discussed in a separate column.
3. Resist the temptation to seek advice from well-meaning animal owners when dealing with canine and feline worm burdens. This area of veterinary medicine has been greatly studied and researched and your veterinarian is best equipped to address the matter.
4. Avoid taking the path of ritualistic treatment protocols and interventions – handed down (often incorrectly) from generation to generation. Clients gleefully report that they have extracted worms from the mouths of their wards with a needle and therefore have rid their pets of the worm infestation. This is a patently false assertion. Roundworms’ larvae (immature stages) migrate (via the blood) into the lungs and are coughed up into the mouth. As advised last week, a visible single worm in the mouth is an indication of a serious intestinal infestation.
5. There are two major categories of drugs that are marketed commercially to eradicate worms in animals; one which expels the live worms into the surrounding environment, and the other which kills the worms in the gut.
The former belongs to a group of medications referred to as “vermifuges.” They serve to weaken the worms, and, because of the natural gut motility, the paralysed worms are expelled in the faeces. It should be noted that even as the worms are being weakened, they will continue to produce eggs which are resilient to the external environment and can be picked up by the same host animal from which they were expelled as well (as well as by others that are living close-by, thereby perpetuating the cycle of worm infestation. In addition, vermifuges are not effective in expelling eggs that were produced in the gut by adult worms. As such, routine deworming is required to continuously reduce and eradicate worms from the gut.
The second category of dewormers is referred to as “vermicides” . They actually kill many of the worms in the gastro-intestinal tract (GIT) and elsewhere. However, it should be noted, that, especially in cases with high levels of infestation, the dead worms become disintegrated by secretions in the stomach and in the gut. This causes somewhat toxic substances to be released and the animal to become visibly ill. Often, vets have to intervene after the use of vermicides, and must counteractive and healing medication. We must recognise that if the dewormer is strong enough to kill or even weaken the worms, it could also have some deleterious side effects on the well-being of the host animal.
ACTUAL TREATMENT:
Commercial preparations of canine and feline anthelmintics (worm killers) are currently available to stun and kill the worms in the stomach and intestines and help with the expulsion of the paralysed or dead worms. Drug companies are constantly producing new broad-spectrum dewormers with new active ingredients that purport to target not only GI tract worms, but also Heartworms and ectoparasites (fleas, ticks, mites, lice). Many veterinarians (and veterinary technicians) use these drugs because they seem to simplify the therapeutic and preventative interventions.
Without endorsing any of the multiple anthelminthic products, I can safely advise that the following considerations be factored into the decisions associated with curing a companion animal that is hosting a worm burden.
1. Consult with your veterinarian for information on the tested and proven efficacy of the products to be used.
2. Evaluate the monthly costs of using a particular anthelmintic and whether you can afford to use it.
3. Consider the ease of administration. Is your pet uncooperative when tablets are to be swallowed? Does the animal reject certain flavours/tastes? (e.g., mint versus fruit flavour). How can you determine if the animal has actually swallowed the full dose of the medication? Dogs are notorious for keeping the tapeworm tablets hidden in their mouths and then spitting them out when the caregiver is out of sight ??.
4. Are you following only the correct dosage rate recommended by the manufacturer? Note that correct dosage rates are dependent on age, physical condition, health status and weight of the animal. This latter consideration requires that you assess the weight fairly accurately.
We will continue the discussion on the treatment of worms next week, and deal specifically with the choice of drugs, alternatives, and the recommended intervals between dewormings as well as the preventative aspects of worm infestations.
