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In the United States, certain breed clubs are strongly recommending screening for "Leishmania", especially in imported breeding stock from endemic locations. For reasons yet unidentified The Foxhound and Neapolitan Mastiff seem to be predisposed or at higher risk for disease. The Italian Spinone Club of America is also requesting all breeders and owners to submit samples for testing; the club reported 150 Spinone Italiano dogs have tested positive in the United States.
In the United States, the following veterinary colleges and government bodies assist with testing and treatment of "Leishmania"-positive dogs:
- Centers for Disease Control and Prevention on Leishmaniasis in dogs
- Iowa State University Department of Pathology
- North Carolina State University College of Veterinary Medicine
Diagnostic testing includes molecular biology and genetic techniques which provide high accuracy and high sensitivity/specificity. The most commonly employed methods in medical laboratories include Enzyme-Linked Immunosorbent Assays, aka ELISA (among other serological assays) and DNA amplification via Polymerase Chain Reaction (PCR).
The Polymerase Chain Reaction(PCR) method for detecting "Leishmania" DNA is a highly sensitive and specific test, producing accurate results in a relatively short amount of time.
A study completed in which Foxhounds were tested using PCR showed that approximately 20% of the tested dogs were positive for leishmaniasis; the same population tested with serological/antibody assays showed only 5% positive.
Diagnosis can be complicated by false positives caused by the leptospirosis vaccine and false negatives caused by testing methods lacking sufficient sensitivity.
In areas where the known vector is a sandfly, deltamethrin collars worn by the dogs has been proven to be 86% effective. The sandfly is most active at dusk and dawn; keeping dogs indoors during those peak times will help minimize exposure.
Unfortunately, there is no one answer for leishmaniasis prevention, nor will one vaccine cover multiple species. "Different virulence factors have been identified for distinct "Leishmania" species, and there are profound differences in the immune mechanisms that mediate susceptibility/resistance to infection and in the pathology associated with disease."
In 2003, Fort Dodge Wyeth released the Leshmune vaccine in Brazil for "L. donovani" (also referred to as "kala-azar" in Brazil). Studies indicated up to 87% protection. Most common side effects from the vaccine have been noted as anorexia and local swelling.
The president of the Brazil Regional Council of Veterinary Medicine, Marcia Villa, warned since vaccinated dogs develop antibodies, they can be difficult to distinguish from asymptomatic, infected dogs.
Studies also indicate the Leshmune vaccine may be reliable in treating "L. chagasi", and a possible treatment for dogs already infected with "L. donovani".
The gold standard for diagnosis is visualization of the amastigotes in splenic aspirate or bone marrow aspirate. This is a technically challenging procedure that is frequently unavailable in areas of the world where visceral leishmaniasis is endemic.
Serological testing is much more frequently used in areas where leishmaniasis is endemic. A 2014 Cochrane review evaluated different rapid diagnostic tests. One of them (the rK39 immunochromatographic test) gave correct, positive results in 92% of the people with visceral leishmaniasis and it gave correct, negative results in 92% of the people who did not have the disease. A second rapid test (called latex agglutination test) gave correct, positive results in 64% of the people with the disease and it gave correct, negative results in 93% of the people without the disease. Other types of tests have not been studied thoroughly enough to ascertain their efficacy.
The K39 dipstick test is easy to perform, and village health workers can be easily trained to use it. The kit may be stored at ambient temperature and no additional equipment needs to be carried to remote areas. The DAT anti-leishmania antigen test, standard within MSF, is much more cumbersome to use and appears not to have any advantages over the K39 test.
There are a number of problems with serological testing: in highly endemic areas, not everyone who becomes infected will actually develop clinical disease or require treatment. Indeed, up to 32% of the healthy population may test positive, but not require treatment. Conversely, because serological tests look for an immune response and not for the organism itself, the test does not become negative after the patient is cured, it cannot be used as a check for cure, or to check for re-infection or relapse. Likewise, patients with abnormal immune systems (e.g., HIV infection) will have false-negative tests.
Other tests being developed include detects erythrosalicylic acid.
Leishmaniasis is diagnosed in the hematology laboratory by direct visualization of the amastigotes (Leishman-Donovan bodies). Buffy-coat preparations of peripheral blood or aspirates from marrow, spleen, lymph nodes, or skin lesions should be spread on a slide to make a thin smear and stained with Leishman stain or Giemsa stain (pH 7.2) for 20 minutes. Amastigotes are seen within blood and spleen monocytes or, less commonly, in circulating neutrophils and in aspirated tissue macrophages. They are small, round bodies 2–4 μm in diameter with indistinct cytoplasm, a nucleus, and a small, rod-shaped kinetoplast. Occasionally, amastigotes may be seen lying free between cells. However, the retrieval of tissue samples is often painful for the patient and identification of the infected cells can be difficult. So, other indirect immunological methods of diagnosis are developed, including enzyme-linked immunosorbent assay, antigen-coated dipsticks, and direct agglutination test. Although these tests are readily available, they are not the standard diagnostic tests due to their insufficient sensitivity and specificity.
Several different polymerase chain reaction tests are available for the detection of "Leishmania" DNA. With this assay, a specific and sensitive diagnostic procedure is finally possible.
Most forms of the disease are transmitted only from nonhuman animals, but some can be spread between humans. Infections in humans are caused by about 21 of 30 species that infect mammals; the different species look the same, but they can be differentiated by isoenzyme analysis, DNA sequence analysis, or monoclonal antibodies.
There are no vaccines or preventive drugs for visceral leishmaniasis. The most effective method to prevent infection is to protect from sand fly bites. To decrease the risk of being bitten, these precautionary measures are suggested:
- Outdoors:
1. Avoid outdoor activities, especially from dusk to dawn, when sand flies generally are the most active.
2. When outdoors (or in unprotected quarters), minimize the amount of exposed (uncovered) skin to the extent that is tolerable in the climate. Wear long-sleeved shirts, long pants, and socks; and tuck your shirt into your pants.
3. Apply insect repellent to exposed skin and under the ends of sleeves and pant legs. Follow the instructions on the label of the repellent. The most effective repellents generally are those that contain the chemical DEET (N,N-diethylmetatoluamide).
- Indoors:
1. Stay in well-screened or air-conditioned areas.
2. Keep in mind that sand flies are much smaller than mosquitoes and therefore can get through smaller holes.
3. Spray living/sleeping areas with an insecticide to kill insects.
4. If you are not sleeping in a well-screened or air-conditioned area, use a bed net and tuck it under your mattress. If possible, use a bed net that has been soaked in or sprayed with a pyrethroid-containing insecticide. The same treatment can be applied to screens, curtains, sheets, and clothing (clothing should be retreated after five washings)."
On February 2012, the nonprofit Infectious Disease Research Institute launched a clinical trial of the visceral leishmaniasis vaccine. The vaccine is a recombinant form of two fused Leishmania parasite proteins with an adjuvant. Two phase 1 clinical trials with healthy volunteers are to be conducted. The first one takes place in Washington (state) and is followed by a trial in India.
Diagnosis is based on the characteristic appearance of non-healing raised, scaling lesions that may ulcerate and become secondarily infected with organisms such as "Staphylococcus aureus", in someone who has returned from an endemic area.
The gold standard for diagnosis is PCR (polymerase chain reaction) helps DNA polymerase to create new strands of DNA equivalent to template given.
The best treatment for cutaneous leishmaniasis is not known. Treatments that work for one species of leishmania may not work for another; it is recommended that advice of a tropical medicine or geographical medicine specialist be sought. Ideally, every effort should be made to establish the species of leishmania by molecular techniques (PCR) prior to starting treatment. In the setting of a developing country, there is often only one species present in a particular locality, so it is usually unnecessary to speciate every infection. Unfortunately, leishmaniasis is an orphan disease in developed nations, and almost all the current treatment options are toxic with significant side effects. The most sound treatment for cutaneous leishmaniasis thus far is prevention.
- "Leishmania major" :"L. major" infections are usually considered to heal spontaneously and do not require treatment, but there have been several reports of severe cases caused by "L. major" in Afghanistan. In Saudi Arabia, a six-week course of oral fluconazole 200 mg daily has been reported to speed up healing. In a randomized clinical trial from Iran, fluconazole 400 mg daily was shown to be significantly more effective than fluconazole 200 mg daily in the treatment of cutaneous leishmaniasis.
- "Leishmania braziliensis" :Treatment with pentavalent antimonials or amphotericin is necessary, because of the risk of developing disfiguring mucocutaneous lesions.
- "Leishmania infantum" :"L. infantum" causes cutaneous leishmaniasis in southern France.
New treatment options are arising from the new oral drug miltefosine (Impavido) which has shown in several clinical trials to be very efficient and safe in visceral and cutaneous leishmaniasis. Recent studies from Bolivia show a high cure rate for mucocutaneous leishmaniasis. Comparative studies against pentavalent antimonials in Iran and Pakistan are also beginning to show a high cure rate for "L. major" and "L. tropica". It is registered in many countries of Latin America, as well in Germany. In October 2006 it received orphan drug status from the US Food and Drug administration. The drug is generally better tolerated than other drugs. Main side effects are gastrointestinal disturbances in the 1–2 days of treatment which does not affect the efficacy.
Secondary bacterial infection (especially with "Staphylococcus aureus") is common and may require antibiotics. Clinicians who are unfamiliar with cutaneous leishmaniasis may mistake the lesion for a pure bacterial infection (especially after isolation of "S. aureus" from bacterial skin swabs) and fail to consider the possibility of leishmaniasis.
The treatment is determined by where the disease is acquired, the species of "Leishmania", and the type of infection.
For visceral leishmaniasis in India, South America, and the Mediterranean, liposomal amphotericin B is the recommended treatment and is often used as a single dose. Rates of cure with a single dose of amphotericin have been reported as 95%. In India, almost all infections are resistant to pentavalent antimonials. In Africa, a combination of pentavalent antimonials and paromomycin is recommended. These, however, can have significant side effects. Miltefosine, an oral medication, is effective against both visceral and cutaneous leishmaniasis. Side effects are generally mild, though it can cause birth defects if taken within 3 months of getting pregnant. It does not appear to work for "L. major" or "L. braziliensis".
The evidence around the treatment of cutaneous leishmaniasis is poor. A number of topical treatments may be used for cutaneous leishmaniasis. Which treatments are effective depends on the strain, with topical paromomycin effective for "L. major", "L. tropica", "L. mexicana", "L. panamensis", and "L. braziliensis". Pentamidine is effective for "L. guyanensis". Oral fluconazole or itraconazole appears effective in "L. major" and "L. tropica".
Diagnosis is achieved most commonly by serologic testing of the blood for the presence of antibodies against the ehrlichia organism. Many veterinarians routinely test for the disease, especially in enzootic areas. During the acute phase of infection, the test can be falsely negative because the body will not have had time to make antibodies to the infection. As such, the test should be repeated. A PCR (polymerase chain reaction) test can be performed during this stage to detect genetic material of the bacteria. The PCR test is more likely to yield a negative result during the subclinical and chronic disease phases. In addition, blood tests may show abnormalities in the numbers of red blood cells, white blood cells, and most commonly platelets, if the disease is present. Uncommonly, a diagnosis can be made by looking under a microscope at a blood smear for the presence of the "ehrlichia" morulae, which sometimes can be seen as intracytoplasmic inclusion bodies within a white blood cell.
Biotechnology companies in the developing world have targeted neglected tropical diseases due to need to improve global health.
Mass drug administration is considered a possible method for eradication, especially for lymphatic filariasis, onchocerciasis, and trachoma, although drug resistance is a potential problem. According to Fenwick, Pfizer donated 70 million doses of drugs in 2011 to eliminate trachoma through the International Trachoma Initiative. Merck has helped The African Programme for the Control of Onchocerciasis (APOC) and Oncho Elimination Programme for the Americas to greatly diminished the effect of Onchocerciasis by donating ivermectin. Merck KGaA pledged to give 200 million tablets of praziquantel over 10 years, the only cure for schistosomiasis. GlaxoSmithKline has donated two billion tablets of medicine for lymphatic filariasis and pledged 400 million deworming tablets per year for five years in 2010. Johnson & Johnson has pledged 200 million deworming tablets per year. Novartis has pledged leprosy treatment, EISAI pledged two billion tablets to help treat lymphatic filariasis.
The prognosis is good for dogs with acute ehrlichiosis. For dogs that have reached the chronic stage of the disease, the prognosis is guarded. When bone marrow suppression occurs and there are low levels of blood cells, the animal may not respond to treatment.
There are currently only two donor-funded non-governmental organizations that focus exclusively on NTDs: the Schistosomiasis Control Initiative and Deworm the World. Despite under-funding, many neglected diseases are cost-effective to treat and prevent. The cost of treating a child for infection of soil transmitted helminths and schistosomes (some of the main causes of neglected diseases), is less than US$0.50 per year, when administered as part of school-based mass deworming by Deworm the World. This programme is recommended by Giving What We Can and the Copenhagen Consensus Centre as one of the most efficient and cost-effective solutions. The efforts of Schistosomiasis Control Initiative to combat neglected diseases include the use of rapid-impact packages: supplying schools with packages including four or five drugs, and training teachers in how to administer them.
Doxycycline and minocycline are the medications of choice. For people allergic to antibiotics of the tetracycline class, rifampin is an alternative. Early clinical experience suggested that chloramphenicol may also be effective, however, in vitro susceptibility testing revealed resistance.
A canine vector-borne disease (CVBD) is one of "a group of globally distributed and rapidly spreading illnesses that are caused by a range of pathogens transmitted by arthropods including ticks, fleas, mosquitoes and phlebotomine sandflies." CVBDs are important in the fields of veterinary medicine, animal welfare, and public health. Some CVBDs are of zoonotic concern.
Many CVBD infect humans as well as companion animals. Some CVBD are fatal; most can only be controlled, not cured. Therefore, infection should be avoided by preventing arthropod vectors from feeding on the blood of their preferred hosts. While it is well known that arthropods transmit bacteria and protozoa during blood feeds, viruses are also becoming recognized as another group of transmitted pathogens of both animals and humans.
Some "canine vector-borne pathogens of major zoonotic concern" are distributed worldwide, while others are localized by continent. Listed by vector, some such pathogens and their associated diseases are the following:
- Phlebotomine sandflies (Psychodidae): "Leishmania amazonensis", "L. colombiensis", and "L. infantum" cause visceral leishmaniasis (see also canine leishmaniasis). "L. braziliensis" causes mucocutaneous leishmaniasis. "L. tropica" causes cutaneous leishmaniasis. "L. peruviana" and "L. major" cause localized cutaneous leishmaniasis.
- Triatomine bugs (Reduviidae): "Trypanosoma cruzi" causes trypanosomiasis (Chagas disease).
- Ticks (Ixodidae): "Babesia canis" subspecies ("Babesia canis canis", "B. canis vogeli", "B. canis rossi", and "B. canis gibsoni" cause babesiosis. "Ehrlichia canis" and "E. chaffeensis" cause monocytic ehrlichiosis. "Anaplasma phagocytophilum" causes granulocytic anaplasmosis. "Borrelia burgdorferi" causes Lyme disease. "Rickettsia rickettsii" causes Rocky Mountain spotted fever. "Rickettsia conorii" causes Mediterranean spotted fever.
- Mosquitoes (Culicidae): "Dirofilaria immitis" and "D. repens" cause dirofilariasis.
No human vaccine is available for ehrlichiosis. Tick control is the main preventive measure against the disease. However, in late 2012 a breakthrough in the prevention of CME (canine monocytic ehrlichiosis) was announced when a vaccine was accidentally discovered by Prof. Shimon Harrus, Dean of the Hebrew University of Jerusalem's Koret School of Veterinary Medicine.
The most common medications used to treat coccidian infections are in the sulfonamide antibiotic family.
Depending on the pathogen and the condition of the animal, untreated coccidiosis may clear of its own accord, or become severe and damaging, and sometimes cause death.
Diagnosis is often made by visualization of yeast cells in tissue, or superficial scrapings. Radiography of the chest reveals interstitial infiltrates in the majority of cases.
Puppies are frequently infected with coccidia from the feces of their mother, and are more likely to develop coccidiosis due to their undeveloped immune systems. Stress can trigger symptoms in susceptible animals.
Symptoms in young dogs include diarrhea with mucus and blood, poor appetite, vomiting, and dehydration. Untreated the disease can be fatal.
Treatment is routine and effective. Diagnosis is made by low-powered microscopic examination of the feces, which is generally replete with oocysts. Readily available drugs eliminate the protozoa or reduce them enough that the animal's immune system can clear the infection. Permanent damage to the gastrointestinal system is rare, and a dog will usually suffer no long-lasting negative effects.
Veterinarians usually attempt diagnosis with skin scrapings from multiple areas, which are then examined under a microscope for mites. "Sarcoptes" mites, because they may be present in relatively low numbers, and because they are often removed by dogs chewing at themselves, may be difficult to demonstrate. As a result, diagnosis in sarcoptic mange is often based on symptoms rather than actual confirmation of the presence of mites. A common and simple way of determining if a dog has mange is if it displays what is called a "pedal-pinna reflex", which is when the dog moves one of its hind legs in a scratching motion as the ear is being manipulated and scratched gently by the examiner; because the mites proliferate on the ear margins in nearly all cases at some point, this method works over 95% of the time. It is helpful in cases where all symptoms of mange are present but no mites are observed with a microscope. The test is also positive in animals with ear mites, an ear canal infection caused by a different but closely related mite (treatment is often the same). In some countries, an available serologic test may be useful in diagnosis.
In Haiti, few cases of human rabies are reported to health authorities. In 2016, a report of a woman who had been exposed to rabies three months prior and was showing symptoms went to the hospital where no treatment was administered to her. Even after being reported to both the CDC and the national Department of Epidemiology and Laboratory Research (DELR), as required by Haiti's surveillance program, the woman ended up passing away. This goes to show the lack of communication and effectiveness in caring for human subjects in Haiti, and the continued focus is on eliminating dog-mediated rabies altogether.
Human diploid cell culture rabies vaccine (HDCV) and purified chick embryo cell culture rabies vaccine (PCEC) are used to treat post-exposure immunization against a human rabies infection. Recommendations for treatment are given by governmental health care organizations and in health literature. Health care providers are encouraged to administer a regimen of four 1-mL doses of HDCV or PCEC vaccines. According to the CDC, these injections should be administered intramuscularly to persons who have not yet been vaccinated for rabies.
For those who are unvaccinated, the first of four doses is administered immediately after exposure to the rabies virus. Additional doses are given three, seven, and fourteen days after the first vaccination. Exposure usually means a bite from a rabid animal.
At an individual patient level, post-exposure prophylaxis (PEP) consists of local treatment of the wound, vaccination, and administration of immunoglobulin, if necessary [3]. At the program level, several components are critical, including: adequate and prompt recognition of the need for PEP by the public, if exposed, and by health officials, prompt and sufficient availability of high-quality PEP, and adequate follow-up of PEP use. Health officials' awareness of the need for PEP after a dog bite can only be achieved if the exposure is attended to immediately and communicated effectively.
The above signs, especially fever, respiratory signs, neurological signs, and thickened footpads occurring in unvaccinated dogs strongly indicate canine distemper. However, several febrile diseases match many of the signs of the disease and only recently has distinguishing between canine hepatitis, herpes virus, parainfluenza and leptospirosis been possible. Thus, finding the virus by various methods in the dog's conjunctival cells or foot pads gives a definitive diagnosis. In older dogs that develop distemper encephalomyelitis, diagnosis may be more difficult, since many of these dogs have an adequate vaccination history.
An additional test to confirm distemper is a brush border slide of the bladder transitional epithelium of the inside lining from the bladder, stained with Dif-Quick. These infected cells have inclusions which stain a carmine red color, found in the paranuclear cytoplasm readability. About 90% of the bladder cells will be positive for inclusions in the early stages of distemper.
A number of vaccines against canine distemper exist for dogs (ATCvet code: and combinations) and domestic ferrets (), which in many jurisdictions are mandatory for pets. Infected animals should be quarantined from other dogs for several months owing to the length of time the animal may shed the virus. The virus is destroyed in the environment by routine cleaning with disinfectants, detergents, or drying. It does not survive in the environment for more than a few hours at room temperature (20–25 °C), but can survive for a few weeks in shady environments at temperatures slightly above freezing. It, along with other labile viruses, can also persist longer in serum and tissue debris.
Despite extensive vaccination in many regions, it remains a major disease of dogs.
To prevent canine distemper, puppies should begin vaccination at six to eight weeks of age and then continue getting the “booster shot” every two to four weeks until they are 16 weeks of age. Without the full series of shots, the vaccination will not provide protection against the virus. Since puppies are typically sold at the age of eight to ten weeks, they typically receive the first shot while still with their breeder, but the new owner often does not finish the series. These dogs are not protected against the virus and so are susceptible to canine distemper infection, continuing the downward spiral that leads to outbreaks throughout the country.
Many human diseases can be transmitted to other primates, due to their extensive biological similarities. As a result, centers that hold, treat, or involve close proximity to primates and some other kinds of animals (for example zoos, researchers, and animal hospitals), often take steps to ensure animals are not exposed to human diseases they can catch. In some cases animals are routinely immunized with the same vaccines given to humans.
- Leishmaniasis - Both zoonotic and anthroponotic.
- Influenza, Measles, pneumonia and various other pathogens - Many primates.
- Tuberculosis - Both zoonotic and anthroponotic, with birds, cows, elephants, meerkats, mongooses, monkeys, and pigs known to have been affected.
A robovirus is a zoonotic virus that is transmitted by a rodent vector (i.e., "ro"dent "bo"rne).
Roboviruses mainly belong to the Arenaviridae and Hantaviridae family of viruses. Like arbovirus ("ar"thropod "bo"rne) and tibovirus ("ti"ck "bo"rne) the name refers to its method of transmission, known as its vector. This is distinguished from a clade, which groups around a common ancestor. Some scientists now refer to arbovirus and robovirus together with the term ArboRobo-virus.
In Haiti, the control of dog rabies is led by the MARNDR while the MSPP manages health-care and rabies prevention in the human population. The separation of these ministries makes it easier for responsibilities to be divided among them. Communication about finding the source of exposure and implementing control methods to prevent further cross-species transmission is also more effective. This task is difficult enough within departments of the same ministry, (e.g., health care and epidemiology), which can be seen in experiences elsewhere. This is why a comprehensive evaluation of Haiti's rabies program should heavily consider the costs and benefits of this separation of responsibilities between the two ministries early on.
Despite a planned mass vaccination for dogs in 2013, no campaign was actually conducted. Authorities in Haiti relied on funds donated by the World Bank for the purchase of approximately 500,000 doses of inactivated, injectable vaccine (IMRAB by Merial). Although the funds were awarded in April 2013, the vaccine itself did not arrive until 2014 when the dog vaccination finally went underway in September 2014. The process as a whole was expected to terminate in January 2015. The lack of manpower needed to deliver faster implementation made it impossible for the campaign to be completed in less than four months.
Another challenge presented is vaccination failure, which usually leads to recurrent rabies in dogs and inconsistent control of the disease. The failures that disrupt annual campaigns or have insufficient coverage, for example, are seen as the main cause for this problem. Another factor is that in Haiti, dog vaccinations have been inconsistently applied. Back in 2012 when the last mass vaccination was led by the MARNDR, approximately 400,000 dogs were vaccinated. With this in mind, considering a current human population of approximately 10,000,000, a relation of one dog per ten people, and aiming to attain 70 percent of vaccine coverage, 700,000 dogs would have to be vaccinated. Assessing the effectiveness of this vaccination campaign is difficult because the dog population figures are unreliable (estimates range from 800,000 to 1,200,000 dogs), and though the overall success seems to be limited.
The number of rabid dogs detected by the MARNDR, MSPP, and CDC is a huge risk to people and is not accurately reflected in their surveillance figures. Although international support is common in both technical help and donations, it is not comprehensive. In addition, the MARNDR, MSPP, and other actors do not communicate effectively because of human resource limitations. That being said, the 2015 elimination goal in the region was compromised and control of the disease could not yet be achieved, despite the efforts of resolute national officials. In conclusion, rabies in the dog population is still a problem and major threat to the Haitian population.