Current trends in canine dirofilariosis in Austria-do we face a pre-endemic status?

May combine two claims.

Most Dirofilaria spp. infections were diagnosed using a screening test for common travel infections (59.6% in total; 72.7% of the D. immitis infections, 35.1% of the D. repens infections and 20% of co-infections) such as antigen-ELISA (71.23%) or PCR-testing (36.30%).

“Most Dirofilaria spp. infections were diagnosed using a screening test for common travel infections (59.6% in total; 72.7% of the D. immitis infections, 35.1% of the D. repens infections and 20% of co-infections) such as antigen-ELISA (71.23%) or PCR-testing (36.30%).”

May combine two claims.

Four owners opted for a slow kill protocol and the monthly moxidectin application resulted in a negative antigen test result in three dogs after six, nine and 10 months, respectively.

“Four owners opted for a slow kill protocol and the monthly moxidectin application resulted in a negative antigen test result in three dogs respectively after six, nine and 10 months, respectively.”

• AssumptionRests on an assumption: A negative antigen test result at 8 months after treatment indicates successful elimination of D. immitis.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Thirty dogs were treated according to the protocol recommended by the American Heartworm Society (AHS) (three injections of melarsomine after pre-treatment with doxycycline and a macrocyclic lactone) or, if requested by the owner, by a slow kill protocol.

“Thirty dogs were treated according to the protocol recommended by the American Heartworm Society (AHS) (three injections of melarsomine after pre-treatment with doxycycline and a macrocyclic lactone) or, if requested by the owner, by a slow kill protocol.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Dogs infected with D. repens were treated with macrocyclic lactones over a period of 6 months.

“Dogs infected with D. repens were treated with macrocyclic lactones over a period of 6 months.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Sixty percent of the co-infected dogs were tested for dirofilariosis because of cardiorespiratory signs.

“Sixty percent of the co-infected dogs were tested for dirofilariosis because of cardiorespiratory signs.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Twenty-three dogs were screened for heartworm disease because of cardiorespiratory symptoms and cardio-ultrasonographical findings.

“Twenty-three dogs were screened for heartworm disease because of cardiorespiratory symptoms and cardio-ultrasonographical findings.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Thirteen different countries could be identified regarding the origin and travel history of the dogs.

“Regarding the origin and travel history of the dogs, thirteen different countries could be identified.”

May combine two claims.

Since 2014, there has been an explicit increase in reported infections with D. immitis and D. repens, with the highest number of 28 cases documented in 2018.

“Since 2014, there has been an explicit increase in reported infections with D. immitis and D. repens, with the highest number of 28 cases documented in 2018.”

• AssumptionRests on an assumption: The observed increase in reported cases reflects a true increase in canine dirofilariosis incidence or prevalence in Austria, rather than being solely due to increased awareness and screening.

May combine two claims.

A total of 17.2% of the dogs (8.1% of the D. immitis infections, 43.2% of the D. repens infections and 10% of the double infections) were diagnosed by an incidental finding of microfilariae in the blood smear (n = 13), mass cytology or histology (n = 9) or urine (n = 3).

“A total of 17.2% of the dogs (8.1% of the D. immitis infections, 43.2% of the D. repens infections and 10% of the double infections) were diagnosed by an incidental finding of microfilariae in the blood smear (n = 13), mass cytology or histology (n = 9) or urine (n = 3).”

May combine two claims.

Documented side-effects, such as local pain reactions at the injection site, were common, but mild and self-limiting within 24 h.

“Documented side-effects, such as local pain reactions at the injection site, were common, but mild and self-limiting within 24 h.”

May combine two claims.

The three treatment protocols used showed a similar outcome after 8 months of treatment and minor side effects, consistent with the literature.

“The three treatment protocols used showed a similar outcome after 8 months of treatment and minor side effects, which is consistent with the literature.”

• AssumptionRests on an assumption: The three treatment protocols can be compared despite non-random assignment of dogs to protocols.

May combine two claims.

Ninety-nine dogs were diagnosed with D. immitis, 37 dogs with D. repens and ten dogs had a co-infection with both nematodes.

“Ninety-nine dogs were diagnosed with D. immitis, 37 dogs with D. repens and ten dogs had a co-infection with both nematodes.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Most dogs were situated in central or eastern Austria.

“Most dogs were situated in central or eastern Austria.”

May combine two claims.

Out of 109 dogs diagnosed with D. immitis, 86 received heartworm treatment and 49 treated dogs were monitored over a period for a minimum of 6 months.

“Out of 109 dogs diagnosed with D. immitis, 86 received heartworm treatment and 49 treated dogs were monitored over a period for a minimum of 6 months.”

May combine two claims.

The dogs tested positive for D. immitis originated from Hungary, Greece, the western Balkans, the Iberian peninsula, Romania, USA or Bulgaria.

“The dogs tested positive for D. immitis originated from Hungary, Greece, the western Balkans, the Iberian peninsula, Romania, USA or Bulgaria.”

• AssumptionRests on an assumption: Owners' reports of dogs' origin and travel history are accurate.

May combine two claims.

Screening for travel infections was conducted using antigen-ELISA (71.23%) or PCR-testing (36.3%).

“Screening for travel infections was conducted using antigen-ELISA (71.23%) or PCR-testing (36.3%).”

May combine two claims.

Most of the dogs originating from Hungary in the present study were from the region of the Great Hungarian Plain, which has been considered an endemic region since 2011.

“Most of the dogs originating from Hungary in the present study were from the region of the Great Hungarian Plain, which has been considered an endemic region since 2011 (Bacsadi et al. 2016).”

• cites Bacsadi et al. 2016 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In the present study, countries most commonly mentioned in the history of dogs infected with D. repens were Hungary, Slovakia and eastern Austria, which are again endemic regions for this infection.

“In the present study, countries most commonly mentioned in the history of dogs infected with D. repens were Hungary, Slovakia and eastern Austria, which are again endemic regions for this infection (Tolnai et al. 2014; Fuehrer et al. 2016; Miterpáková et al. 2016).”

• cites Tolnai et al. 2014 sourceNot checked yet

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• cites Fuehrer et al. 2016 sourceNot checked yet

  Not checked in the free run.

• cites Miterpáková et al. 2016Not checked yet

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May combine two claims.

Most of the infected dogs had been imported from neighbouring countries and all of them were classified adults at the time of crossing the borders.

“Most of the infected dogs had been imported from neighbouring countries and all of them were classified adults at the time of crossing the borders.”

May combine two claims.

Most dogs infected with D. immitis came from (or had a travel history to) Hungary and Greece, both are endemic countries for dirofilariosis disease.

“Most dogs infected with D. immitis came from (or had a travel history to) Hungary and Greece, both are endemic countries for dirofilariosis disease.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Canine subcutaneous dirofilariosis is most commonly an asymptomatic course, but it can also result in a variety of non-specific dermal alterations.

“Canine subcutaneous dirofilariosis is most commonly an asymptomatic course, but it can also result in a variety of non-specific dermal alterations (Genchi et al. 2010; Petry et al. 2015).”

• cites Genchi et al. 2010Not checked yet

  Not checked in the free run.

• cites Petry et al. 2015Not checked yet

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May combine two claims.

Increasing numbers of dogs with a travel history to endemic regions, as well as dogs imported from endemic countries, may serve as carriers for both D. repens and D. immitis and introduce these parasites to non-endemic countries.

“Increasing numbers of dogs with a travel history to endemic regions, as well as dogs imported from endemic countries, may serve as carriers for both D. repens and D. immitis and introduce these parasites to non-endemic countries (Leschnik et al. 2008; Genchi et al. 2009).”

• cites Leschnik et al. 2008Not checked yet

  Not checked in the free run.

• cites Genchi et al. 2009 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

In severe infections, allergic reactions associated with microfilaria sensitisation and Wolbachia-mediated inflammatory reactions have been reported.

“In severe infections, allergic reactions associated with microfilaria sensitisation and Wolbachia-mediated inflammatory reactions have been reported (Rocconi et al. 2012).”

• cites Rocconi et al. 2012Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Typically, there are no inflammatory reactions or capsules located around the parasite, which actively moves under the connective tissue layers.

“Typically, there are no inflammatory reactions or capsules located around the parasite, which actively moves under the connective tissue layers (Genchi and Kramer 2017).”

• cites Genchi and Kramer 2017 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Occasionally, D. repens may be found in the pelvic cavity and mesentery.

“Occasionally, D. repens may be found in the pelvic cavity and mesentery (Mircean et al. 2017).”

• cites Mircean et al. 2017Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Possible cutaneous changes in canine subcutaneous dirofilariosis are nodules, pruritus, thin and fragile skin and ocular conjunctivitis.

“Possible cutaneous changes are nodules, pruritus, thin and fragile skin and ocular conjunctivitis (Hargis et al. 2002; Bourdeau and Roussel 2010; Albanese et al. 2013).”

• cites Hargis et al. 2002Not checked yet

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• cites Bourdeau and Roussel 2010Not checked yet

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• cites Albanese et al. 2013Not checked yet

  Not checked in the free run.

May combine two claims.

Up to 2014, 37 infections with D. repens and 25 infections with D. immitis in dogs in Austria were reported.

“Up to 2014, Fuehrer et al. (2016) reported 37 infections with D. repens and 25 infections with D. immitis in dogs in Austria.”

• cites Fuehrer et al. 2016 sourceNot checked yet

  Not checked in the free run.

Classified as probably not a substantial claim. May combine two claims.

Dirofilariosis is a parasitic vector-borne infection caused by different filarioid parasites of the genus Dirofilaria and can be considered an emerging disease in Europe.

“Dirofilariosis is a parasitic vector-borne infection, caused by different filarioid parasites of the genus Dirofilaria and can be considered an emerging disease in Europe (Morchón et al. 2012).”

• cites Morchón et al. 2012 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

The largest endemic region in Europe is the Padan Plain in Northern Italy, where canine dirofilariosis can be found with a prevalence of 50-80%.

“The largest endemic region in Europe is the Padan Plain in Northern Italy, where canine dirofilariosis can be found with a prevalence of 50–80% (Genchi et al. 2005).”

• cites Genchi et al. 2005 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

As climate change proceeds, more vectors for D. immitis may show increasing occurrence in Europe, which could possibly enable autochthonous transmission of dirofilariosis in previously unaffected countries.

“As climate change proceeds, more vectors for D. immitis may show increasing occurrence in Europe, which could possibly enable autochthonous transmission of dirofilariosis in previously unaffected countries (Leschnik et al. 2008; Genchi et al. 2009; Morchón et al. 2012; Kronefeld et al. 2014).”

• cites Leschnik et al. 2008Not checked yet

  Not checked in the free run.

• cites Genchi et al. 2009 sourceNot checked yet

  Not checked in the free run.

• cites Morchón et al. 2012 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Seven cases of cutaneous dirofilariosis were discussed as autochthonous infections, and no wildlife hosts were detected in Austria.

“Seven cases of cutaneous dirofilariosis were discussed as autochthonous infections; no wildlife hosts were detected in Austria.”

• cites Fuehrer et al. 2016 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

D. immitis is predominantly found in tropical to subtropical climates but can be seen progressively emerging in countries with rather mild climates adjacent to these regions.

“D. immitis is predominantly found in tropical to subtropical climates but can be seen progressively emerging in countries with rather mild climates adjacent to these regions.”

• cites Boreham and Atwell 1988Not checked yet

  Not checked in the free run.

• cites Deplazes et al. 2013Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

All countries mentioned are neighbouring countries of Austria or frequently visited travel destinations and are strongly represented by animal welfare organisations bringing shelter and stray dogs to Austria.

“All countries mentioned are neighbouring countries of Austria or frequently visited travel destinations and are strongly represented by animal welfare organisations bringing shelter and stray dogs to Austria.”

May combine two claims.

The endemisation of dirofilariosis in Austria might only be a matter of time and is probably already concluded for D. repens.

“The endemisation of dirofilariosis in Austria might only be a matter of time and is probably already concluded for D. repens (Morchón et al. 2012; Fuehrer et al. 2016; Capelli et al. 2018).”

• cites Morchón et al. 2012 sourceNot checked yet

  Not checked in the free run.

• cites Fuehrer et al. 2016 sourceNot checked yet

  Not checked in the free run.

• cites Capelli et al. 2018Not checked yet

  Not checked in the free run.

• AssumptionRests on an assumption: The observed increase in reported cases reflects a true increase in canine dirofilariosis incidence or prevalence in Austria, rather than being solely due to increased awareness and screening.

May combine two claims.

Canine dirofilariosis often remains asymptomatic in its course and many affected dogs show no symptoms even after the long incubation period of at least five to 6 months.

“One problem of successfully monitoring the introduction of D. immitis and D. repens from endemic countries is that canine dirofilariosis often remains asymptomatic in its course and many affected dogs show no symptoms even after the long incubation period of at least five to 6 months (Schnieder 2006).”

• cites Schnieder 2006Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

Screening dogs from endemic countries only once for dirofilariosis before they are brought to non-endemic countries is insufficient; tests should be repeated around 6 months after entering the non-endemic region, even if the dogs still appear asymptomatic.

“Screening dogs from endemic countries only once for dirofilariosis before they are brought to non-endemic countries is therefore insufficient and tests should be repeated around 6 months after entering the non-endemic region, even if the dogs still appear asymptomatic.”

Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

One reason for the high percentage of coincidentally diagnosed infections could be a low incidence of this disease on the differential diagnosis lists of Austrian veterinarians.

“One reason for the high percentage of coincidentally diagnosed infections could be a low incidence of this disease on the differential diagnosis lists of Austrian veterinarians.”

May combine two claims.

With several mosquito species in Austria potentially able to transmit Dirofilaria spp. and the expected increase of vectors in Central and Northern European countries due to advancing climate change, the increasing prevalence of dirofilariosis in dogs is a serious risk.

“With several mosquito species in Austria potentially able to transmit Dirofilaria spp. and the expected increase of vectors in Central and Northern European countries due to advancing climate change, the increasing prevalence of dirofilariosis in dogs is a serious risk.”

May combine two claims.

While D. repens is known to occur in dogs throughout Hungary, canine cardiopulmonary dirofilariosis has so far been documented in only a few individual cases.

“While D. repens is known to occur in dogs throughout Hungary, canine cardiopulmonary dirofilariosis has so far been documented in only a few individual cases (Genchi et al. 2005; Fok 2007; Jacsó et al. 2009; Tolnai et al. 2014).”

• cites Genchi et al. 2005 sourceNot checked yet

  Not checked in the free run.

• cites Fok 2007Not checked yet

  Not checked in the free run.

• cites Jacsó et al. 2009 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In Greece, the prevalence of D. immitis was 4.1% out of 750 dogs examined in 2016 and the highest prevalence could be found in northern Greece.

“In Greece, the prevalence of D. immitis was 4.1% out of 750 dogs examined in 2016 and the highest prevalence could be found in northern Greece, where most of the dogs in the present study with a travel history to Greece had travelled (Diakou et al. 2016).”

• cites Diakou et al. 2016 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

The number of reported cases of heartworm disease in Hungarian dogs has risen since 2012, and the geographic distribution of D. immitis has disseminated from a few cases in the south of the country to the whole of eastern and central Hungary.

“It is noteworthy that not only has the number of reported cases of heartworm disease in Hungarian dogs risen since 2012, but also the geographic distribution of D. immitis has disseminated from a few cases in the south of the country to the whole of eastern and central Hungary (Farkas et al. 2014).”

• cites Farkas et al. 2014 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

D. repens has spread even faster to Northern Europe than D. immitis, which could be due to the more frequent subclinical infections and therefore undiagnosed dogs can serve as reservoirs and carriers.

“D. repens has spread even faster to Northern Europe than D. immitis, which could be due to the more frequent subclinical infections and therefore undiagnosed dogs can serve as reservoirs and carriers.”

• cites Genchi et al. 2005 sourceNot checked yet

  Not checked in the free run.

• cites Capelli et al. 2018Not checked yet

  Not checked in the free run.

May combine two claims.

The increase in reported cases might be due to the increasing number of dogs with a travel history to endemic regions and dogs imported from endemic countries, but also due to rising awareness of travel infections affecting dogs and, therefore, an increased and more adequate screening for associated diseases.

“This might be due to the increasing number of dogs with a travel history to endemic regions and dogs imported from endemic countries, but also due to rising awareness of travel infections affecting dogs and, therefore, an increased and more adequate screening for associated diseases (Leschnik et al. 2008; Genchi et al. 2014).”

• cites Leschnik et al. 2008Not checked yet

  Not checked in the free run.

• cites Genchi et al. 2014 sourceNot checked yet

  Not checked in the free run.

• AssumptionRests on an assumption: The observed increase in reported cases reflects a true increase in canine dirofilariosis incidence or prevalence in Austria, rather than being solely due to increased awareness and screening.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

In 2017, 34.33% of 367 dogs were positive for D. immitis and 5.45% positive for D. repens.

“In 2017, 34.33% of 367 dogs were positive for D. immitis and 5.45% positive for D. repens (Radev et al. 2016; Iliev et al. 2017).”

• cites Radev et al. 2016Not checked yet

  Not checked in the free run.

• cites Iliev et al. 2017Not checked yet

  Not checked in the free run.

May combine two claims.

Canine dirofilariosis has a long symptom-free incubation period and many altogether asymptomatic cases.

“which is consistent with preceding studies, showing a long, symptom-free incubation period and many altogether asymptomatic cases of canine dirofilariosis (Schnieder 2006; Bowman and Atkins 2009).”

• cites Schnieder 2006Not checked yet

  Not checked in the free run.

• cites Bowman and Atkins 2009 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

In Romania, D. immitis was found in three and D. repens in four different wild carnivore species in 2017, indicating a considerable reservoir in wild carnivores.

“In Romania, D. immitis was found in three and D. repens in four different wild carnivore species in 2017, indicating a considerable reservoir in wild carnivores (Ionică et al. 2017a).”

• cites Ionică et al. 2017aNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Two studies from Bulgaria found that out of 80 dogs, 15% were positive for infection with D. immitis and 18% for infection with D. repens in 2016.

“Two studies from Bulgaria found that out of 80 dogs, 15% were positive for infection with D. immitis and 18% for infection with D. repens in 2016.”

• cites Radev et al. 2016Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

The current study raises the issue of a considerable increase in imports of adult dogs, with the consequence that more dogs that have been exposed to the pathogen for a potentially longer period of time are entering the country.

“An issue which the current study also raises is the considerable increase in imports of adult dogs, with the consequence that more dogs that have been exposed to the pathogen for a potentially longer period of time are entering the country.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Co-infections seem to be common in areas where both parasites are endemic.

“Co-infections seem to be common in areas where both parasites are endemic (Ionică et al. 2017b).”

• cites Ionică et al. 2017bNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

The spread of dirofilarial infections can be seen in many other European countries.

“The spread of dirofilarial infections can be seen in many other European countries.”

• cites Radev et al. 2016Not checked yet

  Not checked in the free run.

• cites Iliev et al. 2017Not checked yet

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• cites Ionică et al. 2017aNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S2 (checkable).

The increase in canine dirofilariosis in Austria can be considered exemplary for the endemisation of a vector-borne parasitosis and zoonosis in a hitherto non-endemic country.

“which can be considered exemplary for the endemisation of a vector-borne parasitosis and zoonosis in a hitherto non-endemic country.”

Probably not a substantial claim: may not pass S3 (load-bearing).

In the context of this study, heat-treated serum for in-house antigen tests has been practised since 2015.

“The use of heat-treated serum for in-house antigen tests can provide a solution to this problem and therefore has been practised in the context of this study since 2015 (Velasquez et al. 2014; DiGangi et al. 2017).”

May combine two claims.

Possible complications, time, and costs can lead pet owners to opt for a slow kill protocol, demand alternative therapeutic options, or refrain from any therapy.

“Possible complications, as well as the time and costs involved, can lead to pet owners opting for a slow kill protocol, demanding alternative therapeutic options or even refraining from any form of therapy (Ku 2017).”

• cites Ku 2017Not checked yet

  Not checked in the free run.

May combine two claims.

Long prepatency, infections with only male or female macrofilariae, or pre-treatment with macrocyclic lactones can lead to false-negative results.

“Additionally, long prepatency, infections with only male or female macrofilariae or, as mentioned above, pre-treatment with macrocyclic lactones can lead to false-negative results (Deplazes et al. 2013; Drake et al. 2015).”

• cites Deplazes et al. 2013Not checked yet

  Not checked in the free run.

• cites Drake et al. 2015Not checked yet

  Not checked in the free run.

May combine two claims.

Heat treatment of serum samples can lead to false-positive results in dogs successfully treated against macrofilariae but with non-degraded antigen still present, and pre-treatment with heat can increase susceptibility to cross-reactions.

“However, a recent study found that heat treatment of serum samples can lead to false-positive results in dogs that have been successfully treated against macrofilariae but in whose blood non-degraded antigen is still present and that the pre-treatment with heat can also increase the susceptibility to cross-reactions (Savadelis et al. 2018).”

• cites Savadelis et al. 2018Not checked yet

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May combine two claims.

Compared with the current American Heartworm Society treatment protocol, the classic adulticide regime leads more frequently to pulmonary thromboembolism and higher complication rates during treatment.

“Compared with the current American Heartworm Society treatment protocol, the classic regime leads more frequently to pulmonary thromboembolism, thus resulting in higher complication rates during the treatment period (Carreton et al. 2014).”

• cites Carreton et al. 2014Not checked yet

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