CDC Reports Prevalence of Worms Transmitted by Dogs and Cats to Humans is Higher Than Previously Understood

New study showing high rate of Toxocara infection in young children and

youth under age 20 raises public health concerns

Nov 05, 2007, 00:00 ET from Companion Animal Parasite Council

    BEL AIR, Md., Nov. 5 /PRNewswire/ -- About 14 percent of the U.S.
 population is infected with Toxocara, or internal roundworms, contracted
 from dogs and cats. That's according to the results of a Centers for
 Disease Control and Prevention (CDC) study announced today at the American
 Society of Tropical Medicine and Hygiene in Philadelphia.
     The CDC study shows the transmission of Toxocara from dogs and cats to
 people is most common in young children and youth under age 20, and more
 common in non-Hispanic Blacks than in Mexican Americans and non-Hispanic
 Whites of all age groups. It is highest in lower socioeconomic and
 less-educated populations. All children, however, are more susceptible to
 infection given their propensity to play in and sometimes eat contaminated
     Infections are acquired by accidental ingestion of Toxocara eggs found
 in environments contaminated with feces of infected dogs and cats. This
 includes play areas and sandboxes.
     "The results of this study demonstrate that Toxocara infection in the
 United States is more widespread and common than previously understood,"
 said Peter Schantz, VMD, PhD, an epidemiologist in the Division of
 Parasitic Diseases at the CDC and a founding board member of the Companion
 Animal Parasite Council (CAPC). "Although most persons infected with
 Toxocara have no apparent symptoms, this infectious agent is capable of
 causing blindness and other serious systemic illness, which makes it a
 public health issue."
     While rare, the visual impairment most often affects children. Since
 toxocariasis is not a reportable infection, true numbers of cases of visual
 impairment and other syndromes are not known, according to Schantz.
     The nonprofit CAPC was formed to educate pet owners about zoonotic
 disease and steps they can take to virtually eliminate the risk of pets
 making people sick.
     "The CAPC recommends that pet owners administer year-round preventive
 medicines that control internal and external parasites -- such as
 roundworms, heartworm, fleas and ticks -- for the life of their dog or cat
 no matter where they live," said Michael Paul, DVM, executive director of
 the CAPC. "If you prevent parasitic infections in companion animals, you
 greatly reduce the chances of zoonotic transmission to people."
     The American Animal Hospital Association, the American Association of
 Feline Practitioners and Schantz of the CDC all endorse the CAPC guidelines
 that call for year-round parasite control in companion animals to protect
 both pets and people from zoonotic disease. Parasite control today is
 simple, safe and effective. Treating dogs and cats for parasites with a
 monthly product is one of the easiest and most effective ways to keep pets
 healthy and eliminate related health risks to humans.
     Despite the availability of effective treatments to prevent them,
 parasites -- some deadly -- remain a common fact of life for dogs and cats.
 Most companion animals have the potential for exposure to parasites all
 year long. Experts agree there is a year-round threat in all regions of the
 country, even those that experience below-freezing temperatures, since
 parasites such as fleas and ticks thrive inside homes regardless of weather
 conditions outdoors.
     Novartis Animal Health US, Inc. funded the CDC toxocara study.
     About the CAPC
     The nonprofit CAPC ( is an independent
 council of veterinarians and other animal health care professionals
 established to create guidelines for the optimal control of internal and
 external parasites that threaten the health of pets and people. It brings
 together broad expertise in parasitology, internal medicine, public health,
 veterinary law, private practice and association leadership
     About the Centers for Disease Control and Prevention
     As the sentinel for the health of people in the United States and
 throughout the world, CDC ( strives to protect people's
 health and safety, provide reliable health information, and improve health
 through strong partnerships. For more information on Toxocara infection,
 visit. As a
 federal agency, CDC does not promote or endorse specific products.
     For more information, contact:
     Robyn Caulfield, (913) 663-4200 or

SOURCE Companion Animal Parasite Council