SNAP® 3Dx® Test
Prevent the spread of serious mosquito- and tick-borne infections
The SNAP® 3Dx® Test helps you easily test every dog annually for three vector-borne diseases: heartworm, Lyme disease, and ehrlichiosis.
The SNAP 3Dx Test is the standard of care for parasite screening. It provides an accurate, in-house result in just eight minutes.
The SNAP 3Dx Test reinforces your current screening protocol of “diagnose, prevent and treat”—the cornerstones of building your practice—because it:
- Delivers the highest sensitivity of all currently available in-house assays1
- Is easy to interpret, instilling confidence in screening results
- Offers convenient, patient-ready, room-temperature storage
Three more ways the SNAP 3Dx Test can improve your care:
With the superior accuracy of ELISA technology, you can:
- Find low worm-burden cases sooner and more often, and begin treatment when you can do the most good. It’s the only test proven to be more sensitive than other in-house tests in detecting low worm-burden.1
- Count on flexibility to test your way, because ELISA is equally effective on whole blood, serum or plasma.
- Interpret the test results easily every time—it’s the only point-of-care test with a built-in wash step and amplification of a positive reaction, making positives easier to detect.
The SNAP® 3Dx®/4Dx® Test identifies an antibody that is produced only as a result of a B. burgdorferi infection (unlike IFA, which isn’t specific for B. burgdorferi infection). The difference is the unique, revolutionary C6 ELISA technology.
The SNAP 3Dx/4Dx Test is based on the detection of antibody to a highly specific, conserved, immunodominant region of VIsE, a surface antigen, called C6. Antibody concentrations are believed to have a high correlation to the presence of viable spirochetes.2
If left untreated, Lyme disease symptoms can become very serious. Studies have shown that antibiotic therapy is beneficial to both clinically and subclinically infected dogs. C6 antibody declines rapidly after successful treatment and may be well-suited to determine response to therapy.3
- Antibodies from currently available Lyme vaccine have been shown not to cross-react with SNAP® Lyme antibody detection, so you can identify infection in vaccinated dogs.2
- Because no Lyme vaccine is 100% effective, even vaccinated dogs should be tested for Lyme disease during every annual screening visit.
- The SNAP 3Dx/4Dx Test offers superior sensitivity and specificity—When you test before vaccinating, you won’t be vaccinating subclinically Lyme-positive dogs and giving owners a false sense of security.
Early detection is the most effective way to protect your patients because the prognosis is good for early-stage infection, but variable-to-guarded for chronic infections.
The SNAP 3Dx/4Dx Test allows for inexpensive in-house E. canis screening, helping you diagnose sooner. Therefore, treatment can be initiated to prevent the dog from progressing into later stages, where the illness is more difficult to manage.
Ehrlichia specificity is high on the SNAP 3Dx/4Dx Test. The SNAP 3Dx/4Dx Test uses an E. canis-specific peptide for accurate, reliable confirmation of exposure to E. canis, with a specificity of at least 97%.4
Sensitivity and specificity of the SNAP® 3Dx® Test
The heartworm sensitivity values in the table above were generated from mixed worm-burden populations. Sensitivities calculated for samples from dogs with very low worm burdens (<2 female worms) were 92.9% (Study 1, n=28) and 79.2% (Study 2, n=24). Sensitivities calculated for samples from dogs with >2 female worms was 99.2% (Study 1) and 97.4% (Study 2).
Why the SNAP 3Dx Test uses highly purified analytes on the ELISA platform
Purified analytes provide superior specificity and improved sensitivity over traditional whole-cell-based tests (IFA and Western blot). This is because the SNAP® test’s peptide-based technology allows evaluation of only highly specific antibodies for E. canis and Lyme,which helps to eliminate false-positives. By contrast, IFA and Western blot whole-cell tests measure all antibodies generated against these organisms because these antibodies aren’t necessarily unique to Lyme and E. canis. This can result in false-positives.
Resources and support materials for the SNAP® 3Dx® Test
View the package insert (PDF) for detailed instructions.
Frequently asked questions about the SNAP® 3Dx® Test
To determine the test result, read the reaction spots in the result window. Any colour development in the sample spots indicates the presence of heartworm antigen, or B. burgdorferi or E. canis antibody. If no colour develops in the positive control spot, repeat the test.
Any colour development in any of the sample spots indicates a positive result. The amount of antigen or antibody produced by individual dogs differs. So it’s not possible to correlate the colour intensity of the sample spot and the level of infection. Keep in mind that every dog is different.
The SNAP 3Dx Test can be stored in any of the following ways:
- Room-temperature storage (15°–25°C/59°–77°F) for 90 days or until the printed expiration date, whichever occurs first.
- SNAP devices and conjugate can be stored in the refrigerator (2°–7°C/35°–45°F) until the expiration date.
- All components must be allowed to equilibrate to room temperature (15°–25°C/59°–77°F), out of the box for at least 30 minutes prior to use. Do not heat.
The proper storage temperature for the SNAP 3Dx Tests and conjugate is 2°–7°C/35°–45°F until the printed expiration date, or at room temperature (15°–25°C/59°–77°F) for 90 days or until the printed expiration date, whichever occurs first. The conjugate is compromised by freezing; therefore, call our Customer Service Department on 0800 587 602 Option 3 to see if replacement conjugate is available.
The SNAP 3Dx Test, and any other SNAP® test, must be used within two hours of removing it from the foil package.
Whole blood can be used, but it must be anticoagulated (using EDTA or heparin). Serum and plasma are also acceptable sample types.
We recommend re-running the test with the exact ratio of conjugate/sample listed in the package insert—four drops of conjugate and three drops of sample.
Contact our Customer Support Department on 0800 587 602, Option 3, a for technical support questions on your diagnostic kits. You can also view the complete SNAP 3Dx Test package insert here (PDF).
The test result must be read eight minutes after the device is snapped. The test does not contain stop solution, and after eight minutes, colour development may occur that is not related to the sample. Results read after eight minutes should not be reported.
According to the studies that have been performed, there are no known Lyme vaccines that interfere with this test.1 The Lyme portion of the SNAP 3Dx Test identifies the presence of a C6 antibody that is elevated only with active infection. Ehrlichia and heartworm do not have any known vaccination interferences. The SNAP 3Dx Test uses a synthetic peptide that specifically identifies Ehrlichia canis. The heartworm portion of the test detects specific antigens that are common to both male and female worms; however, the uterus is the biggest source of this antigen. As a result, older more sexually mature female worms produce the most antigens.
The heartworm portion is an antigen test, and the Ehrlichia canis and Lyme portions are antibody tests.
The following answers include American Heartworm Society information used with permission.
Heartworm disease (also called dirofilariasis) is a preventable, but serious and potentially fatal, parasitic disease that primarily affects dogs and cats. The heart and lungs are the major organs affected by heartworms in dogs.
Adult heartworms (Dirofilaria immitis) can be up to 14 inches long. They live in the right side of the heart and the pulmonary arteries, which connect the heart to the lungs. Heartworms cause blockage and injury that may lead to heart failure and may damage other organs, including the liver and kidneys. A dog may harbour several hundred heartworms, but in most cases the number is much lower.
Cats usually have smaller and fewer heartworms than dogs, and often don’t exhibit clinical signs until the disease is considerably advanced. Occasionally, heartworms are found in other animals such as foxes, wolves and ferrets. Heartworms can also lodge in the lungs of people and form nodules, but their presence has not been associated with clinical disease.
Mosquitoes transmit heartworms.
- Adult female heartworms release microfilariae into the bloodstream of infected animals. When a mosquito bites an infected animal, it takes up blood containing these microfilariae.
- The microfilariae incubate in the mosquito for 10 to 14 days, during which time they become infective larvae. When the mosquito bites another animal, the infective larvae are passed on to the second animal through the wound.
- Infective larvae migrate through the tissues of the body for two to three months, and then enter the heart and pulmonary arteries, where they reach adult size in another three months. If both sexes are present, the mature worms will mate and produce new microfilariae, and the cycle begins again.
- Adult heartworms may survive for five to seven years in dogs. The mosquito is the only natural agent of transmission for heartworms. Microfilariae cannot mature into adult heartworms without passing through a mosquito.
Cats rarely develop microfilaraemia. When present, microfilariae are usually short-lived. Some cats rid themselves of heartworm infections spontaneously, whereas infective larvae in other cats may mature into adult heartworms that can cause serious disease.
According to the American Heartworm Society:
Pets recently or lightly infected with heartworms may show no signs of disease. In later stages, dogs with heavy or persistent infection may cough, become lethargic, lose their appetites or have difficulty breathing. Owners may first notice that their dogs seem to tire rapidly after only moderate exercise. Fluid may accumulate in the abdomen (ascites) as a result of advanced heartworm infection. Another serious, but less common, manifestation is caval syndrome (a form of liver failure). Animals affected by caval syndrome rapidly become weak and their urine turns dark brown. Caval syndrome requires prompt surgical removal of the heartworms.
Veterinarians can detect heartworm infection in its early stages by examining a dog’s blood for the presence of circulating microfilariae or by performing laboratory tests to look for heartworm antigen (a protein produced by adult heartworms). Radiography of the chest and electro- or echocardiography are also helpful in making a diagnosis, and may indicate the severity of the infection.
Clinical signs in cats are similar. However, most cats never show signs of disease and heartworm infection may be a postmortem diagnosis. While the diagnostic approach to heartworm disease in cats is similar to that used for dogs, diagnosis is much more difficult because cats usually harbour very few adult worms.
Yes, heartworm disease is almost 100% preventable with oral (daily or monthly), topical (monthly) or injectable (biannually) medications.
Prior to beginning a prevention program, a blood test is recommended to detect or rule out the presence of heartworms. Then prescribe an appropriate preventative and tell the pet owner how often and how long that preventative should be administered. You can determine the patient’s risk for heartworm disease on the basis of its species, lifestyle and geographic location.
The American Heartworm Society’s 2007 treatment guidelines encourage annual testing, testing in between prevention product changes, and year-round prevention to manage heartworm disease in dogs and cats. “Annual re-testing is an integral part of ensuring that [prevention] is achieved and that more timely treatment can be provided to dogs that test positive in order to minimise pathology.”1
If your question isn’t answered below, learn more about Lyme disease at www.lyme.org.
One of the most common tick-transmitted diseases worldwide, Lyme disease, or borreliosis, is a multifaceted infectious disease syndrome that can cause serious problems for dogs. Although it’s most frequently reported in people and dogs, Lyme disease has also been seen in cats, horses and cattle.
Lyme disease is caused by the corkscrew-shaped bacterium, or spirochete, Borrelia burgdorferi. The bacterium lives in the gut of the black-legged (or deer tick, Ixodes scapularis) and the Western black-legged tick (Ixodes pacificus), and can be transmitted when an infected tick feeds on a dog, person or other mammal. Black-legged ticks are extremely small, ranging from the size of a grain of sand to the size of a sesame seed.
The CDC brochure, Lyme Disease: A Public Information Guide, states:
“The Lyme disease bacterium, Borrelia burgdorferi, is spread through the bite of infected ticks. The black-legged tick (or deer tick, Ixodes scapularis) spreads the disease in the northeastern and north-central United States, and the western black-legged tick (Ixodes pacificus) spreads the disease on the Pacific coast. These ticks are usually found in wooded areas and have complex life cycles. In some regions, black-legged ticks can spread other diseases in addition to Lyme disease, including babesiosis and anaplasmosis.
In general, ticks need to be attached for 36 to 48 hours before they can transmit the Lyme disease bacterium.”1
Possibly. Where and how your clients live may increase their risk of tick exposure—especially if they garden, hike, camp, hunt, work outdoors or spend time in wooded, brushy or overgrown areas and their dogs accompany them. Black-legged or deer ticks prefer to hide in shady, moist ground litter. But they can be found above ground, clinging to tall grass, brush, shrubs and low tree branches. They also inhabit gardens and lawns, particularly at the edges of woodlands and around old stone walls, where deer and white-footed mice, the ticks’ preferred hosts, thrive.
In most areas of the country, people and their pets are at a moderate to high risk of exposure from April to November. Ticks are most active during these months and people and their pets are spending more time enjoying outdoor activities, but disease onset can occur at any time of the year. Lyme disease transmission is a high concern in both spring and fall. In spring, deer ticks must feed to progress from larvae to nymphs—and then again—to mature into adult ticks.
While a variety of signs may appear, the most common signs of Lyme disease are hidden. Other common signs are recurrent arthritis and lameness that last for only three to four days, sometimes with appetite loss and depression. Dog owners should be aware of these warning signs:
- Sudden occurrence of lameness
- Reluctance to move or a stiff, painful gait
- Warm, swollen joints
- Pain in the legs or throughout the body
- Loss of appetite
- Swollen lymph nodes
Dogs can also develop fatal kidney disease, although rare. Signs of Lyme disease may come and go, vary in intensity from mild to severe, and can mimic many other conditions.
Lyme disease is diagnosed by testing for B. burgdorferi antibodies, noting the presence of clinical signs, ruling out other causes of these signs and observing a response to antibiotic therapy. Experts agree that annual testing in endemic regions provides the best first line of defense against Lyme disease.
Lyme disease is challenging to diagnose. The signs can be very subtle and can be easily mistaken for other medical problems. But with the SNAP® 3Dx®/4Dx® Test, veterinarians can tell whether a dog has been infected with Lyme disease. Then the veterinarian and pet owner can discuss treatment options.
Unfortunately, vaccines aren’t 100% effective. If a dog were infected prior to vaccination, the vaccine would not stop disease from occurring. Having a dog tested adds the benefit of knowing whether or not it has been infected. The SNAP® 3Dx®/4Dx® Test is the only test that can definitively distinguish between vaccinated and infected dogs.
Several broad-spectrum antibiotics can effectively treat Lyme disease, especially in its early stages. In early stages, response to antibiotics is usually seen within three to five days and is often dramatic. Patients should be monitored for clinical response to treatment according to the SNAP® 3Dx®/4Dx® Test Lyme disease treatment protocol (PDF).
No, Lyme disease is not spread by person-to-person contact or by contact with infected animals. However, infected dogs serve as sentinels to indicate the presence of infected ticks in the area, which means that you or the pet owner may also be at risk.
Lyme disease may be prevented through vaccination and tick control. Since ticks carry other devastating diseases, such as Rocky Mountain spotted fever, anaplasmosis and ehrlichiosis, it’s important to keep dogs tick-free.
The SNAP® 3Dx®/4Dx® Test identifies infection. The test’s C6 peptide is highly specific for Borrelia burgdorferi and is only present in the face of active infection. In addition, antibodies from currently available Lyme vaccines have been shown not to cross-react with SNAP® Lyme antibody detection, so you can identify infection in vaccinated dogs.1
It is a potentially life-threatening disease that dogs can get from several common dog ticks.
It is the second most common canine infectious disease in the United States (after parvovirus).
Ehrlichiosis is spread through the bite of infected ticks. The Brown dog tick (Rhipicephalus sanguineus) carries the bacteria and bites the dog, spreading infection. All three stages—nymph, larvae, and adult—can transmit E. canis (the cause of ehrlichiosis). This is the only tick that can survive indoors.
In most areas of the country, people and their pets are at a moderate to high risk of exposure from April to November. Ticks are most active during these months and people and their pets are spending more time enjoying outdoor activities, but disease onset can occur at any time of the year. Ehrlichiosis transmission is a high concern in both spring and fall. In spring, dog ticks must feed to progress from larvae to nymphs—and then again—to mature into adult ticks.
While a variety of signs may appear, the most common signs of ehrlichia infection are hidden. Other common signs, which can range from mild to severe, include loss of appetite, depression, fever and painful joints. If left untreated, the disease can progress to a point at which it causes permanent blindness, autoimmune diseases, bleeding complications and even death. If caught early, the prognosis is usually very good for a full recovery from symptoms.
Veterinarians can perform a simple blood test to determine if a dog has been infected with E. canis. The SNAP 3Dx/4Dx Test screens dogs simultaneously for E. canis, Lyme disease and heartworm disease in just eight minutes.
Ehrlichiosis is challenging to diagnose. The signs may be very subtle and can be easily mistaken for other medical problems. But with the SNAP 3Dx/4Dx Test, veterinarians can tell whether a dog has been infected or exposed to E. canis and then provide treatment options.
A positive SNAP 3Dx/4Dx result should be followed by a CBC to check thrombocyte levels. If thrombocytopenia is evident, treatment may be prescribed (see below). Patients should be retested within 3–6 months; see the Ehrlichiosis protocol (PDF).
Several broad-spectrum antibiotics can effectively treat ehrlichiosis, especially in its early stages. Response to antibiotics is usually seen within two to three days, with the most striking changes being in behaviour and attitude. Dogs experiencing severe anaemia or bleeding problems may initially require a blood transfusion. However, this does nothing to treat the underlying disease. Unfortunately, the chronic form of the disease can be fatal.
No, ehrlichiosis is not spread by person-to-person contact or by contact with infected animals. Although the disease is not transmitted directly from dogs to humans, infected dogs serve as sentinels to indicate the presence of infected ticks in the area, indicating that you or the pet owner may also be at risk.
The best prevention of ehrlichiosis is to keep dogs free of ticks. This should include checking the skin daily for ticks and treating dogs with tick control. Since ticks carry other devastating diseases, such as Lyme disease, anaplasmosis and Rocky Mountain spotted fever, it's important to keep dogs tick-free.
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