Canine infectious disease 2 AI Flashcards
What is the incubation period and shedding period of Bordetella bronchiseptica?
The incubation period is 2 to 6 days and shedding can continue for weeks to months.
What are the clinical signs of kennel cough (ITB)?
Clinical signs include acute onset paroxysmal coughing, oculo-nasal discharge, and sometimes productive coughing.
What scheme was used for reporting cases of Ehrlichia and Babesia?
DEFRA reporting scheme DACTARI
Why did the figures reported through the DEFRA reporting scheme poorly reflect the actual disease incidence?
Voluntary reporting
Which disease has been documented in increasing frequency in both humans and dogs in the UK?
Lyme disease
What are the reasons behind the increasing cases of Lyme disease in the UK?
Increased awareness, better diagnostic tests, and statutory reporting
Which tick species is now established in Poland, Belgium, Germany, and the UK?
Dermacentor reticulatus (the European Meadow tick)
What is the potential opportunity for the transfer of infection in dogs?
Infestation with ticks
Which fungal disease is often referred to as Rift Valley Fever?
Coccidiomycosis
How is the major route of infection of Coccidiomycosis in dogs and cats?
Inhalation
What is the normal habitat for Coccidioides fungal species?
Alkaline sandy soil of the southwestern USA, western Mexico, and Central and South America
What is the suggested dose for Ultra-low aspirin therapy?
0.5mg/kg/BID
What is the duration of treatment for Doxycycline?
30 days
What is the recommended dose of Amoxicillin for young patients?
20 mg/kg
Which drug is suggested for early disease, arthritis, or neurological signs?
Doxycycline (Ronaxan)
How often should Azithromycin be administered?
Every 24 hours
What is the best method for reducing the risk of Lyme disease?
Prevent ticks from attaching or remove them quickly
What is the main target of vaccination against Lyme disease?
Borrelia surface proteins OspA and OspB
What is the duration of treatment for Penicillin G?
14-30 days
Which acaricides are fast-acting against ticks?
Fipronil or the isoxazolines (e.g. afoxolaner)
When does spirochete transmission occur after tick attachment?
At least 24 hours
What is the purpose of vaccination against borreliosis?
To induce antibody formation to Borrelia surface proteins
When is the Merilym 3 vaccine used?
In dogs in geographically at-risk areas or with a high degree of possible exposure
What is the main symptom of babesiosis?
Tick-borne parasitic disease
How long does a tick need to be attached for transmission of spirochetes to occur?
At least 24-48 hours.
What is the minimum attachment time for transmission of spirochetes?
It has never been definitively established.
Where do spirochetes divide in the host?
Within the skin at the site of infection.
In which tissues can spirochetes survive for long periods?
Collagen-rich tissues such as skin and joint structures.
How does Borrelia evade the immune system?
By undergoing changes in their surface proteins and remaining undetected in skin, connective tissue, and the nervous system.
What causes the clinical signs of Lyme disease?
The host’s immunological response to a small number of spirochetes.
What percentage of cases of canine Lyme disease result in active migration of spirochetes through tissue?
Approximately 5-10%.
When was the first documented case of canine Lyme disease in the UK reported?
1990
What is the incidence of Lyme disease in dogs in the UK?
Unknown.
What is the estimated risk of a dog encountering an infected tick in the UK over a tick season?
1 in 200.
What organism does Anaplasma phagocytophilium infect?
granulocytes
What are the clinical signs of Anaplasma infection?
anorexia, listlessness, pyrexia, lameness, joint stiffness and swelling, lymph node enlargement
What is the mode of transmission for Anaplasma platys?
believed to be transmitted by Rhipicephalus sanguineus
What are the diagnostic methods for Anaplasma infection?
microscopic detection, serology, PCR tests
What is the recommended treatment for Anaplasma infection?
doxycycline or enrofloxacin
How can the risk of rickettsial disease be reduced?
prevent tick attachment, use effective acaricides, prompt tick removal
What is the recommended acaricide for reducing tick attachment?
afoxolaner, fipronil, or permethrin
Where do adult Dirofilaria immitis reside in dogs?
Adult Dirofilaria immitis reside in the pulmonary arteries and the right ventricle.
What are the signs of disease caused by adult worms in dogs?
Signs of disease caused by adult worms in dogs include pulmonary hypertension and pulmonary thrombosis.
Which mosquito species are competent vectors for D.immitis in Europe?
Aedes caspius, Aedes geniculatus, and Aedes punctor are competent vectors for D.immitis in Europe.
Where is D.immitis currently endemic?
D.immitis is currently endemic in most of North America and Southern Europe, but not in the UK.
In which areas of the USA is heartworm most prevalent?
Heartworm is most prevalent along the Gulf coast, Eastern Seaboard, and the Mississippi river valleys and tributaries in the USA.
At what age do dogs develop patent adult infections of heartworm?
Dogs less than 6 months of age are not old enough to develop patent adult infections.
Which group of dogs is most commonly affected by heartworm?
Large male dogs housed outdoors are the most commonly affected group of dogs with heartworm.
What are the most common countries from which heartworm-affected animals may originate in Europe?
The most common countries from which heartworm-affected animals may originate in Europe are Spain, Portugal, south of France, Greece, Turkey, and Eastern Europe.
Where is the largest endemic area of heartworm in Europe?
The largest endemic area of heartworm in Europe is along the Po river basin in northern Italy.
What is the life cycle of Dirofilaria immitis?
The life cycle of Dirofilaria immitis involves the ingestion of microfilaria, maturation in the malpighian tubules, migration to the head of the mosquito, and infection of the dog during feeding.
How long does it take for L1 larvae to moul into L2 larvae?
L1 larvae moult into L2 larvae in as little as 14-17 days.
What is the temperature range at which L3 larvae develop?
L3 larvae develop at temperatures between 57F/14C and 82F/28C.
Where do L3 larvae migrate to once they develop?
Once L3 larvae develop, they break out of the malpighian tubules and migrate to the head of the mosquito.
How long does the migration of L3 larvae last?
The migration of L3 larvae lasts 2-3 months.
What is the next moult stage after L3 larvae?
The next moult stage after L3 larvae is L4.
Which side of the heart are immature adults of Dirofilaria immitis carried to?
Immature adults of Dirofilaria immitis are carried to the right side of the heart.
How long does it take for immature adults to reach the pulmonary vasculature?
Immature adults reach the pulmonary vasculature as early as 67 days post-inoculation.
Where is the most Northerly case of heartworm in Europe reported?
The most Northerly case of heartworm in Europe has been reported in Cherbourg, not far from the Southern UK coast.
Which antibiotic has the widest distribution in the body?
Minocycline
What is the order of distribution in the body for Minocycline, Doxycycline, and Tetracycline?
Minocycline > Doxycycline > Tetracycline
Where are concentrations of Tetracycline generally low in the body?
Concentrations in the aqueous fluids are generally low
In which body tissues and fluids is Doxycycline distributed?
Doxycycline is distributed to most body tissues and fluids
Which body tissues and fluids does Minocycline have the highest concentrations in?
Minocycline has the highest concentrations in the central nervous system, prostate, and fluids
What is the mode of action of Tetracycline?
Bacteriostatic with time-dependent effects
What is the mode of action of Doxycycline?
Bacteriostatic with mainly concentration-dependent effects
What is the mode of action of Minocycline?
Bactericidal with time-dependent effects
Which drug is predominantly excreted in urine?
Mostly Tetracycline is excreted in urine (60-80%)
How are most drugs eliminated in excretion?
Most drugs are eliminated in urine as unchanged drug
What happens to smaller amounts of Tetracycline in the body?
Smaller amounts of Tetracycline are metabolized by the liver to inactive drug and excreted in urine
What potential side effects are associated with Tetracycline?
Gastrointestinal upset including nausea and diarrhea
What are the potential side effects of Tetracycline?
Hypersensitivity reactions, keratoconjunctivitis sicca (especially in small breed dogs), esophagitis and stricture, and cholestatic hepatitis
Which breed is at an increased risk of side effects from Tetracycline?
Dobermanns are at an increased risk of side effects
Can Tetracycline cause accumulation in teeth?
Yes, Tetracycline can accumulate in teeth causing yellowish staining
What potential adverse effects are associated with Tetracycline?
Cutaneous drug reactions, nonregenerative anemia secondary to folic acid deficiency in cats
What is the role of vaccination in small animal practice?
Vaccination historically formed the cornerstone of small animal practice
Is annual revaccination still considered routine for cats and dogs?
No, annual revaccination has become controversial
Which organizations have composed guidelines for canine and feline vaccination?
WSAVA, AAHA, ABCD, and AAFP have composed guidelines for vaccination
Where can the WSAVA guidelines for vaccination be found?
www.wsava.org/guidelines/vaccination-guidelines
What is the aim of the vaccination guidelines?
To provide practical information about daily use of vaccinations based on scientific knowledge
Are the vaccination guideline recommendations compulsory?
No, the recommendations are not compulsory
What are the variations between each group’s vaccination recommendations?
There are minor variations between each group’s recommendations
What is the focus of the AAHA Canine Vaccination Guidelines?
The guidelines have a USA and Canadian focus
Who composed the ABCD Matrix Vaccination Guidelines?
The guidelines were composed by the European Advisory Board on Cat Diseases (ABCD)
What is the focus of the AAFP Feline Vaccination Advisory Panel Report?
The report is endorsed by the American Association of Feline Practitioners (AAFP) and the International Society of Feline Medicine & Surgery
Which disease has led to the reconsideration of frequent vaccination?
Concerns over the human MMR vaccination have driven the reconsideration
What is a BSAVA Position statement?
BSAVA is a veterinary organization that has published a position statement
What is Caval syndrome?
Caval syndrome is an acute manifestation of a large worm burden causing obstruction to the tricuspid valve apparatus.
What are the acute signs of Caval syndrome?
Acute signs of Caval syndrome include weakness, hypotension, and shock.
What are the symptoms of right heart failure in Caval syndrome?
Symptoms of right heart failure include jugular venous distension and ascites.
What can cause hemolysis in Caval syndrome?
Hemolysis in Caval syndrome is caused by shear stress on red cells.
How is the diagnosis of Caval syndrome made?
The diagnosis of Caval syndrome is based on clinical signs and demonstrating the presence of microfilariae.
What are the two methods for demonstrating the presence of microfilariae?
The presence of microfilariae can be seen on blood films or documented with antigen tests.
Why is direct microscopic examination for microfilariae relatively insensitive?
Direct microscopic examination is relatively insensitive because microfilariae numbers vary.
What is the sensitivity and specificity of in-house ELISA tests for detecting adult parasite antigens?
In-house ELISA tests for detecting adult parasite antigens can reach 100% sensitivity and specificity.
What is the purpose of the modified Knott’s test?
The modified Knott’s test is used to detect the presence of microfilariae and allows for better morphological assessment of the nematode present.
What are the findings in routine bloodwork for dogs with Caval syndrome?
Routine bloodwork may reveal eosinophilia, basophilia, and mild increases in liver enzymes.
What changes can be seen on thoracic radiographs in advanced cases of Caval syndrome?
In advanced cases, thoracic radiographs may show a pulmonary arterial bulge and enlarged, tortuous pulmonary arteries.
Where can adult worms be visualized in Caval syndrome?
Adult worms can be visualized in the main pulmonary artery and less often in the right side chambers of the heart.
What are the initial treatment options for low worm burdens in Caval syndrome?
Conservative management, anti-inflammatory doses of steroids, and thoracocentesis with diuretics can be used as initial treatment options.
What should be considered to reduce the risk of thromboembolic disease in Caval syndrome?
Aspirin or clopidogrel should be considered to reduce the risk of thromboembolic disease.
What is the drug of choice for killing adult worms in Caval syndrome?
The drug melarsomine is the drug of choice for killing adult worms in Caval syndrome.
What is the three-injection approach for treating Caval syndrome with melarsomine?
The three-injection approach involves a single injection followed by a pair of injections 24 hours apart after 50 days.
What role do Wolbachia organisms play in the pathogenesis of canine and feline heart disease?
Wolbachia organisms play a role in the pathogenesis of canine and feline heart disease.
What is the role of doxycycline in the treatment of Wolbachia in Caval syndrome?
Doxycycline is used to treat Wolbachia in Caval syndrome and has been shown to improve clinical outcomes.
What is the main factor responsible for the development of antimicrobial resistance?
Selection of resistant strains through antimicrobial use.
What is the evidence that antimicrobial use contributes to the development of resistance?
Identification of resistance genes in bacteria from ancient DNA.
Why is the development of new antimicrobial drugs unlikely to cope with the increasing resistance?
Antimicrobial resistance is mounting at a faster pace than drug development.
What is the importance of rational prescribing and careful stewardship of antimicrobial use?
To minimize the development of resistance in small animal practice.
What are the two considerations before prescribing antimicrobials?
Is therapy necessary? Is there an alternative treatment?
What percentage of consultations in the UK involved the prescription or administration of antimicrobials to dogs and cats?
33% to 48%
What did Wayne and colleagues find in their study on antimicrobial administration in a US teaching hospital?
Only 17% of instances had a confirmed infection, 45% had a suspected infection, and 38% had no documented evidence of infection.
How can client expectation for antibiotic administration be reduced?
By educating owners about the need for antimicrobial therapy.
What are the potential alternative therapies for viral infections or self-limiting diseases?
Symptomatic relief, cough suppressants, and non-steroidal anti-inflammatory drugs.
Why is antimicrobial therapy unlikely to significantly alter the clinical course of kennel cough in dogs?
Kennel cough has a short, self-limiting course and is associated with low morbidity.
When should prophylactic antibacterials be reserved for routine surgeries?
For patients at an increased risk, such as immunocompromised patients or those undergoing prolonged surgery.
How effective is a single pre-emptive one-off intravenous antimicrobial treatment in reducing infection compared to a 5-day course of postoperative?
Equally effective in reducing infection.
What does the presence of fever or an elevation in white blood cell count suggest?
Inflammatory reaction, which may be driven by viral infection or a sterile inflammatory process.
When does a well cat with a cat bite abscess not require systemic antimicrobial therapy?
When the abscess has been lanced and cleaned.
Are antimicrobials warranted for clean elective, non-traumatic procedures in healthy animals?
No, they are not needed.
Are antimicrobials warranted for procedures that involve entry into the urinary or gastrointestinal systems?
No, they are not needed for such procedures.
What is the key approach to minimizing the development of antimicrobial resistance in small animal practice?
Rational prescribing of optimised therapy and careful stewardship of antimicrobial use.
What are the two cases of Leishmania reported in dogs without a history of travel?
Leishmania reported in un-traveled dogs co-housed with infected imported animals and obtained from UK rehoming centers.
How is Leishmania transmitted between dogs?
Through mechanical dog to dog transmission or another as yet undetermined vector.
What is the role of female sand flies in the life cycle of Leishmania?
They harbor Leishmania promastigotes in their gut and transmit them during feeding.
What happens to the Leishmania promastigotes when they are injected into the host’s skin?
They are phagocytosed by macrophages and multiply to amastigotes.
How does Leishmania disseminate to the visceral organs?
Amastigotes penetrate adjacent cells and disseminate to the visceral organs.
How does the Leishmania life cycle complete?
Cells containing amastigotes are taken up by the sand fly during feeding.
Aside from sand flies, what other mode of transmission is reported for Leishmania?
Vertical transmission in utero and transmission via blood transfusion.
What determines if a dog infected with Leishmania will develop clinical signs?
The immune response mounted by the dog.
What is the prevalence of Leishmania infection in dogs in endemic areas?
Around 60-70% of dogs are infected with Leishmania.
What are the classic signs of Leishmania in dogs?
Weight loss, lymphadenopathy, lameness, cutaneous signs, pale mucous membranes, splenomegaly, abnormal nails, ocular involvement.
What type of immune response leads to chronic and progressive disease in Leishmania?
A humoral Th2 response.
What type of immune response usually leads to clearance of the disease in Leishmania?
A Th1 cell-mediated response.
Which breeds are more susceptible than average to developing symptomatic Leishmaniosis?
German Shepherd, Boxer, Cocker Spaniel, and Rottweiler.
What is the focus of vaccination strategies and therapeutic options for Leishmaniosis?
Producing an effective Th1 response.
What are the common clinical signs of Leishmania in dogs?
Cutaneous signs, weight loss, lymphadenopathy, abnormal nails, and proteinuria.
How can Leishmaniosis be diagnosed in a sick dog?
By documenting the presence of the organisms or by detecting an immune response through serology.
For which dogs should Leishmaniosis be considered if they have traveled to endemic areas?
Native British dogs that have traveled to endemic areas.
What is the primary vaccination course for Borrelia burgdorferi (Lyme disease) in dogs at high risk of exposure?
The primary vaccination course for Borrelia burgdorferi (Lyme disease) in dogs at high risk of exposure is recommended at 16 weeks and a booster at 6-12 months.
What is maternally derived immunity and how does it relate to the level of transfer of antibodies from the bitch to the puppy?
Maternally derived immunity is the immunity passed from the mother dog to the puppy through antibodies. The level of transfer of antibodies is determined by the dam’s own level of immunity and the puppy’s ingestion of colostrum in the immediate post-natal period.
What are the two potential issues caused by the level of maternally derived antibodies (MDA) at the time of primary vaccination?
The two potential issues caused by the level of maternally derived antibodies (MDA) at the time of primary vaccination are an ‘immunity gap’ and interference with response to vaccination.
How can the second issue of interference with response to vaccination be overcome?
The second issue of interference with response to vaccination can be overcome by giving the final dose of the primary course (potentially as a third dose) at 16 weeks or later for core canine and feline vaccines, with a booster at 6-12 months of age.
According to WSAVA guidelines, what is the recommended age to start the primary vaccination course for puppies to permit socialization before 10 weeks of age?
According to WSAVA guidelines, starting the primary vaccination course at 6-7 weeks of age would require 4 doses of vaccine to complete the course after 16 weeks, while starting at 8-9 weeks of age would require 3 doses.
What is the recommended revaccination frequency for canine core vaccines (Distemper, Parvovirus, Adenovirus-2)?
Canine core vaccines (Distemper, Parvovirus, Adenovirus-2) should be revaccinated no more frequently than triennial (every 3 years) after the primary course and 6-12 months booster.
What is the recommended revaccination frequency for Rabies vaccine in pet dogs and cats?
The revaccination frequency for Rabies vaccine in pet dogs and cats should be according to the vaccine license duration of immunity (DOI) and statute considerations in areas where rabies vaccination is a legal requirement.
What are some factors to consider for the individual pet when conducting a risk/benefit assessment for vaccination?
Some factors to consider for the individual pet when conducting a risk/benefit assessment for vaccination are age, environment, travel, entire bitches, current treatment, current general health, prior vaccination history, and unknown vaccination history or elapsed vaccinations for adults.
What types of vaccine products vary in efficacy?
Different vaccine products targeting the same infectious agent can vary in efficacy.
What are inactivated vaccines and what do they contain?
Inactivated vaccines contain killed bacteria or viruses, eliminating the risk of replication post inoculation or ‘reversion to virulence’.
What is the mutant selection window (MSW)?
The mutant selection window is the difference between the MIC and the MPC.
Why is it important to keep the mutant selection window (MSW) as small as possible?
To limit the development of antimicrobial resistance.
Which fluoroquinolone has a very narrow MSW compared to other older fluoroquinolones?
Pradofloxacin.
What is the potential impact of using newer and less commonly used antimicrobials?
Controversial and may limit resistance development.
What is the cause of coliform resistance to carbapenems?
Production of New Delhi metallo beta-lactamase (NDM-1).
What has happened to the research and development of new antimicrobials?
It has slowed down.
What is MRSA?
Methicillin-resistant Staphylococcus aureus.
What is the genetic mutation found in MRSA?
mecA.
What is the binding protein coded by mecA?
Penicillin binding protein 2 (PBP2).
What kind of antibiotics is MRSA resistant to?
All beta-lactam antibiotics.
What are some commonly used antibiotics that MRSA is often susceptible to?
Others than beta lactams.
What is the percentage of people carrying wild type Staphylococcus aureus within their nasal passages?
Approximately 30%.
What percentage of the general population are asymptomatic carriers of MRSA?
1-3%.
What percentage of health care workers are asymptomatic carriers of MRSA?
Up to 15%.
In what cases may MRSA evolve resistance to other classes of antibiotics?
Widespread use of antibiotics, such as in hospitals.
What can cause more severe disease in MRSA?
Acquisition of virulence factors such as panton valantin leucocidin.
Can dogs and cats acquire MRSA?
Yes, but they usually acquire it from people (reverse zoonosis).
What is the natural commensal of dogs and cats for Staphylococcus pseudintermedius?
They are natural reservoir hosts.
What is the resistance that has been reported in Staphylococcus pseudintermedius?
Methicillin resistance (MRSP).
What are some drug resistance genes acquired by MRSP?
Fluoroquinolones, TPMS, and tetracycline.
What is the role of domperidone in the immune response to infection?
Domperidone is a dopamine receptor antagonist that modulates the Th1 immune response.
What are the gastric actions of domperidone?
Domperidone is used for its gastric prokinetic and anti-emetic actions.
How does domperidone affect dopamine receptors?
Domperidone acts as a dopamine receptor antagonist.
What is the effect of domperidone’s anti-dopaminergic action?
The anti-dopaminergic effect of domperidone results in the release of serotonin.
What is the function of prolactin in the immune response?
Prolactin is a pro-inflammatory cytokine that helps modulate the Th1 immune response.
What did a clinical study of domperidone in dogs with infection find?
A clinical study found that domperidone reduced clinical signs and antibody titres in affected dogs with no reported side effects.
What supportive treatments may be needed for renal dysfunction in Leishmaniosis?
Supportive treatments may include ACE inhibitors for protein losing nephropathy and antibiotics for secondary bacterial pyoderma.
What symptoms are commonly associated with feline Leishmaniosis?
Cutaneous nodular or ulcerative lesions are most common, but a wide variety of symptoms are reported.
Is there an increased prevalence of Leishmaniosis in cats with immunosuppressive viruses?
There is no confirmed increased prevalence of Leishmaniosis in cats with FIV and FeLV.
What are some preventative measures for Leishmaniosis in dogs traveling to endemic areas?
Reducing exposure to sand flies is essential, such as keeping animals housed during dawn and dusk and using deltamethrin-impregnated collars to reduce bites.
What does the canine vaccination against Leishmania utilize?
The canine vaccination utilizes a specific mixture of Leishmania surface proteins with a specific saponin adjuvant to direct the immune system to a Th1 cell mediated response.
What did a field trial show about the effectiveness of the Leishmania vaccine?
The vaccine was shown to reduce the risk of infection by fourfold in dogs housed outside without any other preventative treatment.
How often should the Leishmania vaccine be administered?
The induction course is 3 injections at 3 weekly intervals, with annual boosters thereafter.
Are there any reported side effects of the Leishmania vaccine?
Transient mild injection site reactions have been reported with a slightly higher frequency than for standard canine vaccinations.
What are some guidelines for the diagnosis and clinical classification of leishmaniasis in dogs?
Guidelines include PCR and serological studies, clinical signs, and classification based on severity.
What is the purpose of guidelines for preventing leishmaniasis in dogs?
The guidelines aim to provide preventive measures to help reduce the risk of leishmaniasis in dogs.
How does dose optimization optimize efficacy?
Dose optimization optimizes efficacy by ensuring antimicrobial concentrations stay above MIC for a therapeutic effect.
What potential side effects can occur with high doses of metronidazole?
High doses of metronidazole can lead to neurological side effects.
What potential side effects can occur with aminoglycosides in patients with renal insufficiency?
Aminoglycosides in patients with renal insufficiency can cause side effects.
When should follow-up culture and sensitivity be performed after completing antimicrobials?
Follow-up culture and sensitivity should be performed 3-7 days after completing antimicrobials.
What is the purpose of performing follow-up culture and sensitivity?
Follow-up culture and sensitivity allows documentation of both clinical and microbiological cure.
What does a clinical cure without microbiological cure indicate?
A clinical cure without microbiological cure may indicate the presence of potentially resistant bacteria.
What can be done to treat antimicrobial resistant bacterial infections?
Other therapies like topical disinfectants or topical wound management can be used.
What is the importance of directly removing the site of infection?
Directly removing the site of infection reduces bacterial burden and improves penetration of antimicrobials.
What are some mechanisms through which antimicrobials damage and kill bacteria?
Antimicrobials can target cell wall assembly, bacterial DNA, and ribosomal protein assembly.
How can bacteria become resistant to antimicrobials?
Bacteria can become resistant through random mutations or acquiring resistance genes.
What are some ways resistance genes confer resistance in bacteria?
Resistance genes can alter binding proteins, produce inactivating enzymes, or decrease membrane permeability.
How can resistance genes be transferred between bacteria?
Resistance genes can be transferred through transformation, conjugation, and transduction.
What is the frequency of genetic mutations conferring antimicrobial resistance in bacteria?
Genetic mutations conferring antimicrobial resistance occur at a low frequency in growing populations of bacteria.
Why do antimicrobials favor the development of resistance in bacteria?
Antimicrobials select for resistant isolates of bacteria by killing off susceptible isolates.
What is the importance of follow-up cultures in assessing resistance?
Follow-up cultures help assess resistance as MIC testing may not reliably identify resistance.
How does testing for the mutant prevention concentration (MPC) help identify resistance?
Testing with larger inoculums can identify resistance arising from spontaneous mutations.
What is the alternative treatment for heartworm infection in dogs?
Surgical removal via a vascular approach.
What is the recommended approach for surgical removal of heartworms in the right side of the heart?
Ishihara forceps through a right-sided jugular approach.
What is the significance of subcutaneous dirofilariasis?
Most infections are asymptomatic.
What is the recommended prophylaxis for preventing heartworm infection?
Monthly milbemycin or selemectin.
How long should heartworm prophylaxis be continued after returning to the UK?
At least 1 month.
What mosquito species transmits subcutaneous dirofilariasis?
Different mosquito species than those transmitting D. immitis.
How are subcutaneous nodules caused by D. repens treated?
They are normally removed surgically.
What type of preventatives are usually successful in preventing disease transmission of subcutaneous dirofilariasis?
Macrolide preventatives used for D. immitis.
What are the references for further reading on dirofilariasis?
Bandi et al, 1999; Kramer et al, 2008; Lee et al, 2010; Liotta et al, 2013; McCall et al, 2005; Nelson et al, 2005; Schnyder & Deplazes, 2012; Small et al, 2008; Venco et al, 2014.
Who discovered penicillin?
Sir Alexander Fleming.
Who discovered sulphonamides?
Gerhard Domagk.
What revolutionized the treatment of bacterial disease in both human and veterinary medicine?
The discovery of penicillin and sulphonamides.
What has been noted since the start of antimicrobial use?
Resistance to antimicrobials.
What is the prevalence of MRSP in the community?
Around 2%
What is the prevalence of MRSP in referral hospitals?
16-20%
What is the sensitivity to potentiated amoxicillin of Staphylococcus pseudintermedius isolates in a teaching hospital in 2007?
<60%
Where can further information on the management of MRSA/MRSP be found?
BSAVA guidelines and Bella Moss Foundation website
What are the key points to help prevent the development of drug resistant infections?
Rational use of antibiotics, practice infection control, consider alternative treatments
Which drug class inhibits bacterial protein synthesis?
Aminoglycosides
Which drug class inhibits bacterial cell wall synthesis?
Cephalosporin
Which drug class inhibits DNA gyrase action?
Fluoroquinolones
What is the mechanism of Pradofloxacin, a 3rd generation fluoroquinolone?
Inhibits topoisomerase action, reduces mRNA translation
What is the spectrum of 1st generation cephalosporins?
Gram-negative bacteria, some gram-positive bacteria
What is the spectrum of Pradofloxacin?
Gram-negative bacteria, gram-positive bacteria, limited anaerobic action
How are cephalosporins generally absorbed?
Generally well absorbed from the gut
How is Pradofloxacin administered?
Parenteral route
What are potential side effects of aminoglycosides?
Gastrointestinal upset, irreversible damage to auditory and vestibular components
What is the potential side effect of enrofloxacin at higher doses?
Retinal degeneration and blindness
What can lead to renal failure in enrofloxacin?
Accumulation of agent in the cells of the proximal tubule
What are the potential side effects of antibiotic treatment?
Nephrotoxicity, ototoxicity, hematopoietic effects, hypersensitivity reactions
Is fatal anaphylaxis likely with aminoglycosides?
Very unlikely
What should be considered when prescribing beta-lactams?
Potential cross reaction to all beta-lactams
What are the appropriate cases for prophylactic antibacterial use?
Only in a few cases such as immune compromised patients.
How can inappropriate antibacterial prescribing be reduced?
By prescribing other options for symptomatic relief.
What factors should be considered when selecting antibacterials?
Type of bacteria, distribution and penetration of the drug, and potential side effects.
Why is it better to use narrow spectrum antibacterials?
They limit effects on commensal organisms.
When should cultures be performed?
When prolonged courses are likely to be needed or when empirical treatment has failed.
How should antimicrobial treatment be administered?
Treat long enough at a sufficient dose and then stop. Avoid under dosing.
What should be monitored when using culture results?
Culture profiles should be tracked and recorded.
How can owner compliance with antimicrobial therapy be improved?
Through owner education and newer, more palatable formulations.
What factors affect drug penetration to the site of infection?
Site of infection, degree of inflammation, and blood supply.
Which antimicrobial might be a better choice for ocular infections?
Topical antimicrobials.
Which antimicrobial is effective for the treatment of chronic prostatitis?
Fluoroquinolones that function as zwitterions.
Which antimicrobials are usually confined to extracellular fluid and the vascular space?
Water-soluble antimicrobials like beta-lactams.
Which type of antimicrobials cross cell membranes and are more useful against intracellular organisms?
Lipid-soluble antimicrobials like fluoroquinolones and tetracyclines.
How can the therapeutic effect of antimicrobial treatment be improved in lesions with necrotic and/or purulent material?
By using trimethoprim potentiated sulphonamides or aminoglycosides.
What type of antimicrobial action do fluoroquinolones and metronidazole have?
Dose or concentration-dependent antimicrobial action.
In which cases can increased dose of enrofloxacin be used effectively?
To treat otherwise resistant Pseudomonas aeruginosa infections.
Who composed the guidelines on vaccination of companion animals?
A group of experts in internal medicine, infectious diseases, and immunology.
What may appear contrary to pharmaceutical companies datasheets?
Some of the recommendations in the guidelines.
How did the VMD respond to the confusion caused by contradictory recommendations?
With a position paper stating that veterinarians have the authority to make clinical benefit/risk judgments.
What factors should be considered when deciding on the necessity of vaccination for an individual animal?
Age, health, home environment, travel plans, and lifestyle.
According to the BSAVA vaccination position statement, what should be discussed with clients?
A thorough benefit/risk assessment on an individual case basis for timing of vaccination and use of particular vaccines.
How have pharmaceutical companies responded to the change in vaccination approach?
By developing individual agent vaccines and revising administration frequency recommendations on the SPC.
What is required if vaccines are used ‘off license’?
Informed and documented owner consent.
What has been suggested as the emphasis of the annual visit to the vet?
An annual health assessment with a focus on preventative health measures.
How have canine and feline vaccinations been classified by WSAVA and AAFP?
Core/non-core, and core/circumstantial/non-core by ABCD.
What category has been included by WSAVA?
A category of ‘not recommended’.
What are the core canine vaccines in the UK?
Canine Distemper Virus, Canine Adenovirus/Infectious Canine Hepatitis, Canine Parvovirus, and Leptospirosis.
What is the legal requirement for dogs traveling abroad or returning to the UK under the Pet Travel Scheme?
Rabies vaccination.
For which type of dog is Canine Herpes Virus vaccine recommended?
Breeding bitches.
When should vaccination be considered for the ‘Kennel Cough’ vaccine?
Before kenneling or situations where dogs mix with other dogs.
Which vaccine should be considered before traveling to an endemic area for Leishmaniasis?
Leishmaniasis vaccine.
How long does it take for immature adults to reach sexual maturity?
3 months
What is the length of young immature adults?
2.5-3.5cm
How long does it take for adult worms to reach sexual maturity after inoculation?
190-280 days
When is the peak time for producing microfilariae in the circulation?
7-9 months after infection
How long do adult worms live in a dog?
5-7 years
How long do microfilaria live?
2 years
What does recent interest focus on as a target for diagnosis and treatment?
Wolbachia
What is the possible impact of global warming on Dirofilaria?
It may start to be seen in the UK
How are microfilariae transferred to mosquitos?
They are ingested by mosquitos
Where do microfilariae migrate to and mature into adults?
Pulmonary arteries
What are the typical signs of heartworm disease in dogs?
Coughing, dyspnoea, chronic weight loss, exercise intolerance, and syncope
What are the clinical signs of dogs in right-sided congestive heart failure?
Jugular distension, ascites, hepatomegaly
How many classes have infected dogs been subdivided into based on clinical signs?
Three
What are the clinical signs of dogs in Class 1 heartworm disease?
None to occasional cough
What are the clinical signs of dogs in Class 2 heartworm disease?
Cough, moderate exercise intolerance
What are the clinical signs of dogs in Class 3 heartworm disease?
Persistent cough, exercise intolerance, weight loss
What are the clinical signs of dogs in Class 4 heartworm disease?
Cough, exercise intolerance, weight loss, dyspnoea, overt right-sided heart failure
What are some components that may be included in vaccines?
Stabilizers, preservatives, antibiotics, adjuvants, and excipient proteins
What is the mode of action of adjuvants in vaccines?
Prolong release of antigen, activate macrophages, and stimulate lymphocyte activity
What are the commonly used adjuvants in vaccines?
Aluminum salts and mineral oils
What are modified-live vaccines (MLV)?
Vaccines containing attenuated bacteria or viruses that induce an immune response without causing disease
How are recombinant vaccines produced?
Genetic sequences coding for immunogenic proteins are isolated from the pathogen and recombined with live non-pathogenic viruses or bacteria for vaccine production
What are some adverse effects of vaccination in dogs?
Injection site reactions, transient non-specific symptoms, immune-mediated reactions, tumorigenesis
What are the types of immune-mediated adverse reactions to vaccination?
Acute hypersensitivity (Type I), delayed cytotoxic (Type II), immune complex (Type III)
What is feline injection site sarcoma associated with?
Inflammation locally at injection sites, possibly due to other injections
What can cause local abscessation/cellulitis or hepatopathy when administering Bordetella intranasal vaccine?
Accidental parenteral administration
What are some factors that can cause vaccine ‘failure’?
Maternally derived antibodies, poor immunogenicity, incorrect handling or administration, poor immune response of the individual
What are the three classifications of surgical wounds?
Clean, clean-contaminated, and dirty
What factors should be considered when assessing the need for antimicrobial therapy?
Patient status, immune system, potential numbers and virulence of bacteria
What type of infection is likely in a clean-contaminated surgery with spillage but no infection present?
Presence of contaminating organisms
How can bacterial numbers be reduced at surgical sites?
Through meticulous lavage, debridement, and cleaning
What type of wound classification is an infected surgical site with purulent discharge?
Dirty
When should antimicrobials be used in most cases?
During clean-contaminated surgery due to likely presence of high numbers of contaminating organisms
What is the recommended approach to guide antimicrobial therapy?
Use culture and sensitivity results whenever possible
How can the emergence of antimicrobial resistance be limited?
By using therapy only when infection is documented and having a small number of front line antimicrobials for routine use
What does the PROTECT acronym stand for in the PROTECT-ME scheme?
Rational use of antimicrobials: Practice policy, Reduce prophylaxis
What is the purpose of antimicrobial sensitivity testing?
To determine if bacteria are sensitive or resistant to a specific antimicrobial
Who is the module developer for Module 15 of Small Animal Medicine?
Simon Tappin
What are the learning objectives for Module 15?
Review Leishmania and Dirofilaria, recall clinical signs, outline diagnosis and treatment options, reflect on preventative strategies, outline causes of antimicrobial resistance, explain culture and sensitivity testing, consider options for optimizing antimicrobial therapy, outline vaccine types, explain immunity gap, consider serological monitoring and adverse reactions to vaccination.
What is Leishmaniosis?
A serious and fatal protozoan disease of dogs and occasionally cats.
Where is Leishmaniosis endemic?
Mediterranean areas of Europe, South America, and the Middle East.
What is the causative species of Leishmaniosis in southern Europe?
Leishmania infantum.
What is the vector for Leishmania infantum?
The Phlebotomus sand fly.
What limits endemic Leishmaniosis to southern Europe?
The specific habitat and climate requirements for the sand fly vector.
What is the estimated number of dogs with Leishmaniosis in south west Europe?
At least two and a half million.
How is L. infantum transmission from dogs to people mainly facilitated?
Through sand flies.
Who is particularly susceptible to Leishmaniosis?
Children and immunosuppressed adults.
Are sand flies present in the United Kingdom?
No.
How is Leishmaniosis being introduced to the UK?
Through animals traveling from endemic areas in Europe.
What is the name of the national reporting scheme for exotic diseases in the UK?
DACTARI (Dogs and Cat Travel and Risk Information).
How many cases of Leishmaniosis have been reported through the DACTARI scheme?
51 cases.
What were the most commonly reported countries of origin for dogs with Leishmaniosis entering the UK?
Spain, Greece, Portugal, and Italy.
How many cases of Leishmaniosis were documented in the UK between 2005 and 2007?
257 cases.
What specific method can be used to diagnose Leishmania infection?
Cytological examination of fine needle aspirates or PCR
What is the sensitivity of PCR in acute Leishmania infection?
88%
What is the main aim of treatment for Leishmaniosis?
Controlling the clinical signs rather than curing the disease
What is the mainstay of treatment for Leishmaniosis?
Allopurinol
What are the side effects of meglumine antimoniate?
Possible nephrotoxicity for 4 weeks and pain on injection
What is the mechanism of action of miltefosine?
Inhibition of cell signaling and membrane synthesis leading to cell death
What is the potential risk of using allopurinol for Leishmaniosis treatment?
Xanthine urolithiasis
What is the advantage of using miltefosine over meglumine antimoniate for treatment?
Oral administration and liver metabolism
What is a disadvantage of using miltefosine for treatment of Leishmaniosis?
Gastrointestinal side effects
What may cause drug resistance to meglumine antimoniate and miltefosine?
Reported cases in humans
What are the potential side effects of drugs in man when given with NSAID?
Gastrointestinal upset
What is the mechanism of action of Lincosamide drugs?
Inhibitor by binding to the 50S ribosome and inhibiting peptide bond formation
What is the spectrum of Macrolide drugs?
Gram positive cocci and bacilli, mycoplasma, and some gram negative bacilli
How are Penicillin drugs eliminated?
Mostly excreted as inactive metabolites in urine
What is the mode of action of Tetracycline drugs?
Inhibition of bacterial protein synthesis by binding to the 30S ribosomal subunit
What is the pharmacokinetics of Penicillin drugs?
Absorption varies by drug, but generally well absorbed from the gut
What are the effects of Potentiated sulphonamides against anaerobes?
Poor
