Dirofilaria in Humans, Dogs, and Vectors in Austria (1978–2014)—From Imported Pathogens to the Endemicity of Dirofilaria repens
Open accessAbstract
BACKGROUND: Dirofilaria repens and D. immitis are filarioid helminths with domestic and wild canids as main hosts and mosquitoes as vectors. Both species are known to cause zoonotic diseases, primarily pulmonary (D. immitis), ocular (D. repens), and subcutaneous (D. repens) dirofilariosis. Both D. immitis and D. repens are known as invasive species, and their distribution seems associated with climate change. Until very recently, both species were known to be nonendemic in Austria. METHODOLOGY AND PRINCIPAL FINDINGS: Metadata on introduced and possibly autochthonous cases of infection with Dirofilaria sp. in dogs and humans in Austria are analysed, together with analyses of mosquito populations from Austria in ongoing studies. In Austria, most cases of Dirofilaria sp. in humans (30 cases of D. repens-six ocular and 24 subcutaneous) and dogs (approximately 50 cases-both D. immitis and D. repens) were most likely imported. However, occasionally infections with D. repens were discussed to be autochthonous (one human case and seven in dogs). The introduction of D. repens to Austria was confirmed very recently, as the parasite was detected in Burgenland (eastern Austria) for the first time in mosquito vectors during a surveillance program. For D. immitis, this could not be confirmed yet, but data from Germany suggest that the successful establishment of this nematode species in Austria is a credible scenario for the near future. CONCLUSIONS: The first findings of D. repens in mosquito vectors indicate that D. repens presumably invaded in eastern Austria. Climate analyses from central Europe indicate that D. immitis also has the capacity to establish itself in the lowland regions of Austria, given that both canid and culicid hosts are present.
AI snapshot
Written from the paper’s full text.
TL;DR
This review compiles Austrian records from 1978–2014 and finds that human and dog Dirofilaria infections were mostly imported, but D. repens was detected in mosquitoes in Burgenland in 2012 and is considered to be establishing in eastern Austria. D. immitis remains nonendemic in Austria, though conditions and neighboring-country data suggest establishment is plausible.
Key findings
- In humans, 30 D. repens cases were reported since 1978: 24 subcutaneous (80%) and six ocular (20%); 27 patients reported travel to at least one D. repens-endemic country, and one case in Nickelsdorf, Burgenland (2006) was discussed as autochthonous. Three suspected human pulmonary D. immitis cases were serology-positive but not biopsy-confirmed.
- In dogs, D. repens was detected in 37 dogs, including 26 monoinfections; seven (27%) monoinfections had unclear travel activity, and all potentially autochthonous cases were from eastern Austria. D. immitis was documented in 25 dogs, with 81% of examined dogs having travel history to the Mediterranean and no case suspected as autochthonous.
- D. repens DNA was first detected in Austrian mosquitoes in 2012 in pools of An. algeriensis in Rust and An. maculipennis complex in Mörbisch, both in Burgenland. No D. repens or D. immitis were observed in screened Austrian foxes (n = 36 eastern Austria; n > 500 western Austria).
- The authors conclude that D. repens presumably invaded eastern Austria, while D. immitis is not yet endemic but may become established in the near future.
Methods
- The study summarizes published and unpublished cases of D. repens and D. immitis in dogs, humans, and mosquitoes in Austria. Published cases were identified via NCBI, Scopus, and Google Scholar using keywords “Dirofilaria” and “Austria,” including German-language literature; unpublished cases came from electronic patient databases at the University of Veterinary Medicine Vienna and the Medical University of Vienna.
- Metadata on introduced and possibly autochthonous infections were analyzed together with ongoing mosquito population studies; fox blood samples from eastern Austria (n = 36) and western Austria (n > 500) were also screened for filarioid helminths.
Limitations
- The paper states that vector competence of several mosquito species remains unclear because molecular analyses used whole mosquitoes, including the abdomen, which cannot confirm vector competence.
- The paper states that the three suspected human pulmonary D. immitis cases were not confirmed by invasive biopsy because of the lung location, and that stable establishment of D. repens is still to be seen because all potential autochthonous cases were documented within a relatively short time span.
- Evident from the text: many human and dog records rely on unpublished patient data, and travel histories were sometimes unclear or not determined, limiting certainty about autochthonous acquisition.
Model-written summary. Check it against the paper before relying on it.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
0 of 49 cited sources checked · 0 supported · 0 flagged
- Findingown data
For D. immitis, establishment in Austria could not be confirmed yet.
“For D. immitis, this could not be confirmed yet”
Quote in the paperSubstantial claim - Findingown data
Of the 30 human D. repens cases in Austria, 24 (80%) were subcutaneous infections and six (20%) ocular lesions.
“Of these, 24 (80%) were subcutaneous infections and six (20%) ocular lesions.”
Quote in the paperNot a substantial claim - Findingcitation
In September 2006, a 34-year-old border police officer from Nickelsdorf (Burgenland) presented a 1 cm diameter tumor on the right palm after a mosquito bite.
“In September 2006, a 34-year-old border police officer from Nickelsdorf (Burgenland) presented a “tumor” 1 cm in diameter on the right palm of her hand after a mosquito bite.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [18] H Auer, 2008, Der erst authochthone Fall einer subkutanen Dirofilariose in Österreich, Wien Klin Wochenschr source
Not checked in the free run.
- Findingown data
The introduction of D. repens to Austria was confirmed very recently, as the parasite was detected in Burgenland (eastern Austria) for the first time in mosquito vectors during a surveillance program.
“The introduction of D. repens to Austria was confirmed very recently, as the parasite was detected in Burgenland (eastern Austria) for the first time in mosquito vectors during a surveillance program.”
Quote in the paperSubstantial claim - Findingnone given
Since 1978, 30 cases of human dirofilariosis caused by D. repens were reported in Austria.
“Since 1978, 30 cases of human dirofilariosis caused by D. repens were reported in Austria”
Quote in the paperNot a substantial claim
- Findingown data
Twenty-seven of the 30 human D. repens patients in Austria reported travel activity to at least one country known to be endemic for D. repens prior to infection.
“Twenty-seven patients reported travel activity to at least one country known to be endemic for D. repens prior to infection.”
Quote in the paperNot a substantial claim - Findingcitation
Only one human case of subcutaneous dirofilariosis in Austria was discussed as an autochthonous acquired infection.
“Only one human case of subcutaneous dirofilariosis was discussed as autochthonous acquired infection [18].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [18] H Auer, 2008, Der erst authochthone Fall einer subkutanen Dirofilariose in Österreich, Wien Klin Wochenschr source
Not checked in the free run.
- Rests on an assumption: Reported travel activity or its absence reliably indicates whether a Dirofilaria infection was imported or acquired autochthonously.
- Findingown data
All 30 human D. repens patients in Austria presented clinical symptoms (appearance of skin nodes or wandering skin pain).
“All patients presented clinical symptoms (appearance of skin nodes or wandering skin pain).”
Quote in the paperNot a substantial claim - Findingcitation
Three suspected cases of human pulmonary dirofilariosis caused by D. immitis have been observed in Austria so far.
“Three suspected cases of human pulmonary dirofilariosis cases caused by D. immitis have been observed in Austria so far [19].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [19] Auer H. Die Dirofilariose des Menschen Epidemiologie and Nosologie einer gar nicht so seltenen Parasitose in Osterreich (Nematoda, Spirurida, Onchocercidae). Denisia; 2004; 463–471.
Not checked in the free run.
- Findingreasoning
With the exception of one case in Gablitz (west of Vienna), all potentially autochthonous D. repens cases in dogs in Austria were documented at the border areas to Slovakia and Hungary.
“With the exception of one case in Gablitz (west of Vienna), all of those cases were documented at the border areas to Slovakia and Hungary.”
Quote in the paperNot a substantial claim- Rests on an assumption: Reported travel activity or its absence reliably indicates whether a Dirofilaria infection was imported or acquired autochthonously.
- Findingown data
All potentially autochthonous cases of D. repens in dogs in Austria (with no reported time spent abroad) were reported from eastern Austria (Lower Austria and Burgenland) only.
“All potentially autochthonous cases (with no reported time spent abroad) were reported from eastern Austria (Lower Austria and Burgenland) only (Fig 2).”
Quote in the paperSubstantial claim- Rests on an assumption: Reported travel activity or its absence reliably indicates whether a Dirofilaria infection was imported or acquired autochthonously.
- Findingown data
In all other D. repens monoinfection cases in dogs in Austria, the pathogens were found incidentally or during travel screening.
“In all other cases, the pathogens were found incidentally or during travel screening.”
Quote in the paperNot a substantial claim - Findingown data
Fifteen (58%) of the dogs infected with D. repens in Austria (including mixed infections with D. immitis) had previous travel activity to countries neighboring Austria known to be endemic for D. repens (Hungary, Slovakia, or Germany).
“Fifteen (58%) of the dogs infected with D. repens (including mixed infections with D. immitis) had previous travel activity to countries neighboring Austria known to be endemic for D. repens (Hungary, Slovakia, or Germany).”
Quote in the paperNot a substantial claim - Findingown data
Seven (27%) of the D. repens monoinfections in dogs in Austria were reported in Austrian dogs whose travel activity remained unclear.
“Seven (27%) of the monoinfections were reported in Austrian dogs whose travel activity remained unclear.”
Quote in the paperNot a substantial claim - Findingown data
In only five cases (19%) of the D. repens monoinfections in dogs in Austria did symptoms like skin nodules lead to the diagnosis of dirofilariosis.
“In only five cases (19%) of the monoinfections did symptoms like skin nodules lead to the diagnosis of dirofilariosis.”
Quote in the paperNot a substantial claim - Findingown data
Overall, D. repens was detected in 37 dogs in Austria.
“Overall, D. repens was detected in 37 dogs in Austria (Table 3).”
Quote in the paperNot a substantial claim - Findingown data
Excluding epidemiological surveys and mixed infections with D. immitis, 26 dogs in Austria presented monoinfections with D. repens.
“Excluding epidemiological surveys and mixed infections with D. immitis, 26 dogs presented monoinfections.”
Quote in the paperNot a substantial claim - Findingown data
To date, neither D. repens nor D. immitis have been observed in Austrian foxes or other possible wild hosts.
“to date, neither D. repens nor D. immitis have been observed in Austrian foxes or other possible wild hosts.”
Quote in the paperNot a substantial claim - Findingown data
Dirofilaria immitis was documented in 25 dogs in Austria.
“Filarioid helminths of the species D. immitis were documented in 25 dogs in Austria (Table 3).”
Quote in the paperNot a substantial claim - Findingown data
81% of examined dogs with D. immitis in Austria had a history of travel activity to the Mediterranean region prior to infection.
“81% of the examined dogs had a history of travel activity to the Mediterranean region (e.g., Italy, Greece) prior to infection”
Quote in the paperNot a substantial claim - Findingown data
No case of D. immitis in Austria was suspected to be an autochthonous infection from Austria.
“no case was suspected to be an autochthonous infection from Austria.”
Quote in the paperNot a substantial claim - Findingown data
Mixed D. repens and D. immitis infections were examined in three dogs, all of which had reported travel activity.
“Mixed D. repens and D. immitis infections were examined in three dogs, all of which had reported travel activity.”
Quote in the paperNot a substantial claim - Findingnone given
To date, these are the only findings of autochthonous Dirofilaria spp. in mosquitoes in Austria.
“To date, these are the only findings of autochthonous Dirofilaria spp. in mosquitoes in Austria.”
Quote in the paperSubstantial claim - Interpretationown data
The first findings of D. repens in mosquito vectors indicate that D. repens presumably invaded in eastern Austria.
“The first findings of D. repens in mosquito vectors indicate that D. repens presumably invaded in eastern Austria.”
Quote in the paperSubstantial claim- Rests on an assumption: Detection of D. repens in mosquito vectors in Burgenland indicates local transmission and establishment of D. repens in eastern Austria.
- Interpretationreasoning
Climate analyses from central Europe indicate that D. immitis has the capacity to establish itself in the lowland regions of Austria, given that both canid and culicid hosts are present.
“Climate analyses from central Europe indicate that D. immitis also has the capacity to establish itself in the lowland regions of Austria, given that both canid and culicid hosts are present.”
Quote in the paperSubstantial claim- Rests on an assumption: Climate analyses from central Europe are applicable to Austria for assessing the capacity of D. immitis to establish.
- Interpretationreasoning
About 30% of the human D. repens infections in Austria were estimated to have been acquired in neighboring countries of Austria.
“About 30% of these infections were estimated to have been acquired in neighboring countries of Austria.”
Quote in the paperNot a substantial claim- Rests on an assumption: Reported travel activity or its absence reliably indicates whether a Dirofilaria infection was imported or acquired autochthonously.
- Interpretationown data
In Austria, most cases of Dirofilaria sp. in humans (30 cases of D. repens-six ocular and 24 subcutaneous) were most likely imported.
“In Austria, most cases of Dirofilaria sp. in humans (30 cases of D. repens—six ocular and 24 subcutaneous) and dogs (approximately 50 cases—both D. immitis and D. repens) were most likely imported.”
Quote in the paperSubstantial claim- Rests on an assumption: Reported travel activity or its absence reliably indicates whether a Dirofilaria infection was imported or acquired autochthonously.
- Interpretationcitation
Data from Germany suggest that the successful establishment of D. immitis in Austria is a credible scenario for the near future.
“For D. immitis, this could not be confirmed yet, but data from Germany suggest that the successful establishment of this nematode species in Austria is a credible scenario for the near future.”
Quote in the paperNot a substantial claim- Rests on an assumption: Data from Germany on D. immitis establishment are applicable to Austria.
- Interpretationown data
In Austria, most cases of Dirofilaria sp. in dogs (approximately 50 cases-both D. immitis and D. repens) were most likely imported.
“In Austria, most cases of Dirofilaria sp. in humans (30 cases of D. repens—six ocular and 24 subcutaneous) and dogs (approximately 50 cases—both D. immitis and D. repens) were most likely imported.”
Quote in the paperSubstantial claim- Rests on an assumption: Reported travel activity or its absence reliably indicates whether a Dirofilaria infection was imported or acquired autochthonously.
- Premisecitation
An epidemiological study conducted in eastern Austria documented microfilariae of D. repens in one of eight dogs in Gänserndorf (Lower Austria) and six of 90 dogs in Neusiedl (Burgenland) by PCR and Knott test.
“However, an epidemiological study conducted in eastern Austria documented the findings of microfilariae of D. repens in one of eight dogs in Gänserndorf (Lower Austria) and six of 90 dogs in Neusiedl (Burgenland) by PCR and Knott test [20].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [20] G Duscher, 2009, Nachweis von Dirofilarien in österreichischen Hunden, Berl Munch Tierarztl Wochenschr
Not checked in the free run.
- Premisereasoning
D. repens was documented in most central European areas prior to D. immitis.
“and it is obvious that D. repens was documented in most central European areas prior to D. immitis.”
Quote in the paperNot a substantial claim0 of 9 sources checked- cites [3] F Simón, 2012, Human and animal dirofilariasis: the emergence of a zoonotic mosaic, Clin Microbiol Rev source
Not checked in the free run.
- cites [7] R Morchón, 2012, Heartworm Disease (<italic>Dirofilaria immitis</italic>) and Their Vectors in Europe—New Distribution Trends, Front Physiol source
Not checked in the free run.
- cites [11] C Genchi, 2011, Dirofilarial infections in Europe, Vector Borne Zoonotic Dis source
Not checked in the free run.
- cites [12] E Bocková, 2013, <italic>Dirofilaria repens</italic> microfilariae in <italic>Aedes vexans</italic> mosquitoes in Slovakia, Parasitol Res source
Not checked in the free run.
- cites [13] R Sassnau, 2009, <italic>Dirofilaria repens</italic> infestation in a sled dog kennel in the federal state of Brandenburg (Germany). Diagnosis and therapy of canine cutaneous dirofilariosis, Tierarztl Prax Ausgabe K Kleintiere—Heimtiere
Not checked in the free run.
- cites [14] M Kronefeld, 2014, Molecular detection of <italic>Dirofilaria immitis</italic>, <italic>Dirofilaria repens</italic> and <italic>Setaria tundra</italic> in mosquitoes from Germany, Parasit Vectors source
Not checked in the free run.
- cites [15] C Czajka, 2014, Stable transmission of <italic>Dirofilaria repens</italic> nematodes, northern Germany, Emerg Infect Dis source
Not checked in the free run.
- cites [16] Z Svobodová, 2006, The first report of authochthonous dirofilariosis in dogs in the Czech Republic, Helminthologia source
Not checked in the free run.
- cites [17] C Zittra, 2015, Screening blood-fed mosquitoes for the diagnosis of filarioid helminths and avian malaria, Parasit Vectors source
Not checked in the free run.
- Premisecitation
By now (with the exception of Liechtenstein), both D. repens and D. immitis have been reported in all countries neighboring Austria (Germany, the Czech Republic, Slovakia, Hungary, Slovenia, Italy, and Switzerland).
“By now (with the exception of Liechtenstein), both parasites have been reported in all countries neighboring Austria (Germany, the Czech Republic, Slovakia, Hungary, Slovenia, Italy, and Switzerland) [3,7,11–17]”
Quote in the paperNot a substantial claim0 of 9 sources checked- cites [3] F Simón, 2012, Human and animal dirofilariasis: the emergence of a zoonotic mosaic, Clin Microbiol Rev source
Not checked in the free run.
- cites [7] R Morchón, 2012, Heartworm Disease (<italic>Dirofilaria immitis</italic>) and Their Vectors in Europe—New Distribution Trends, Front Physiol source
Not checked in the free run.
- cites [11] C Genchi, 2011, Dirofilarial infections in Europe, Vector Borne Zoonotic Dis source
Not checked in the free run.
- cites [12] E Bocková, 2013, <italic>Dirofilaria repens</italic> microfilariae in <italic>Aedes vexans</italic> mosquitoes in Slovakia, Parasitol Res source
Not checked in the free run.
- cites [13] R Sassnau, 2009, <italic>Dirofilaria repens</italic> infestation in a sled dog kennel in the federal state of Brandenburg (Germany). Diagnosis and therapy of canine cutaneous dirofilariosis, Tierarztl Prax Ausgabe K Kleintiere—Heimtiere
Not checked in the free run.
- cites [14] M Kronefeld, 2014, Molecular detection of <italic>Dirofilaria immitis</italic>, <italic>Dirofilaria repens</italic> and <italic>Setaria tundra</italic> in mosquitoes from Germany, Parasit Vectors source
Not checked in the free run.
- cites [15] C Czajka, 2014, Stable transmission of <italic>Dirofilaria repens</italic> nematodes, northern Germany, Emerg Infect Dis source
Not checked in the free run.
- cites [16] Z Svobodová, 2006, The first report of authochthonous dirofilariosis in dogs in the Czech Republic, Helminthologia source
Not checked in the free run.
- cites [17] C Zittra, 2015, Screening blood-fed mosquitoes for the diagnosis of filarioid helminths and avian malaria, Parasit Vectors source
Not checked in the free run.
- Premisecitation
Various species of the genera Aedes, Ochlerotatus, Culex, Culiseta, Coquillettidia, and Anopheles are potential vectors of Dirofilaria spp. in Europe.
“Various species of the genera Aedes, Ochlerotatus, Culex, Culiseta, Coquillettidia, and Anopheles are potential vectors of Dirofilaria spp. [3,7] in Europe.”
Quote in the paperNot a substantial claim0 of 2 sources checked- cites [3] F Simón, 2012, Human and animal dirofilariasis: the emergence of a zoonotic mosaic, Clin Microbiol Rev source
Not checked in the free run.
- cites [7] R Morchón, 2012, Heartworm Disease (<italic>Dirofilaria immitis</italic>) and Their Vectors in Europe—New Distribution Trends, Front Physiol source
Not checked in the free run.
- Premisecitation
The first potential autochthonous findings of D. repens north of the Alpine Arc were documented in 11 clinically asymptomatic dogs from the south of Switzerland in 1998.
“The first potential autochthonous findings of D. repens north of the Alpine Arc were documented in 11 clinically asymptomatic dogs from the south of Switzerland in 1998 [10].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [10] H Bucklar, 1998, Breitet sich in der Südschweiz die Dirofilariose beim Hund aus?, Schweiz Arch Tierheilkd
Not checked in the free run.
- Premisecitation
Potential vectors of D. immitis in Austria are Coquillettidia richardii, Ae. albopictus, Oc. caspius, Ae. vexans, An. maculipennis complex, Cx. pipiens complex, and Cx. modestus.
“Potential vectors of D. immitis in Austria are Coquillettidia richardii, Ae. albopictus, Oc. caspius, Ae. vexans, An. maculipennis complex, Cx. pipiens complex, and Cx. modestus [3,7,14,17].”
Quote in the paperNot a substantial claim0 of 4 sources checked- cites [3] F Simón, 2012, Human and animal dirofilariasis: the emergence of a zoonotic mosaic, Clin Microbiol Rev source
Not checked in the free run.
- cites [7] R Morchón, 2012, Heartworm Disease (<italic>Dirofilaria immitis</italic>) and Their Vectors in Europe—New Distribution Trends, Front Physiol source
Not checked in the free run.
- cites [14] M Kronefeld, 2014, Molecular detection of <italic>Dirofilaria immitis</italic>, <italic>Dirofilaria repens</italic> and <italic>Setaria tundra</italic> in mosquitoes from Germany, Parasit Vectors source
Not checked in the free run.
- cites [17] C Zittra, 2015, Screening blood-fed mosquitoes for the diagnosis of filarioid helminths and avian malaria, Parasit Vectors source
Not checked in the free run.
- Premisecitation
DNA of D. repens was examined in pools of An. algeriensis in Rust and An. maculipennis complex in Mörbisch, both in Burgenland, bordering Hungary.
“DNA of D. repens was examined in pools of An. algeriensis in Rust and An. maculipennis complex in Mörbisch, both in the federal state of Burgenland, bordering Hungary (Fig 2).”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [22] K Silbermayr, 2014, Autochthonous <italic>Dirofilaria repens</italic> in Austria, Parasit Vectors source
Not checked in the free run.
- Interpretationreasoning
D. immitis does not appear to be endemic in Austria.
“D. immitis does not appear to be endemic in Austria”
- Also stated in: § Key Learning Points · plain
“Until now, D. immitis is only associated with travel activity, and the parasite is not (yet) endemic in Austria.”
Quote in the paperSubstantial claim - Also stated in: § Key Learning Points · plain
- Premisecitation
D. repens in Austria was detected in mosquitoes in 2012 for the first time in a nationwide mosquito surveillance and monitoring program.
“D. repens in Austria was detected in mosquitoes in 2012 for the first time in a nationwide mosquito surveillance and monitoring program [22].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [22] K Silbermayr, 2014, Autochthonous <italic>Dirofilaria repens</italic> in Austria, Parasit Vectors source
Not checked in the free run.
- Premisecitation
Several models have shown that the expansion of Dirofilaria from southern to central and northern Europe, up to 50° N in the case of D. immitis, is most probable.
“Several models have shown that the expansion from southern to central and northern Europe (up to 50° N in the case of D. immitis) is most probable.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [24] C Genchi, 2005, Is heartworm disease really spreading in Europe?, Vet Parasitol source
Not checked in the free run.
- Premisecitation
Both the heartworm predictive model and the Dirofilaria development units show parts of eastern Austria as suitable for the introduction and/or establishment of D. repens as well as D. immitis.
“Both the heartworm predictive model (based on growing degree days) and the Dirofilaria development units show parts of eastern Austria (the regions where most D. repens cases in dogs, the findings in mosquitoes, and the human case were documented) as suitable for the introduction and/or establishment of D. repens as well as D. immitis [24].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [24] C Genchi, 2005, Is heartworm disease really spreading in Europe?, Vet Parasitol source
Not checked in the free run.
- Premisecitation
The preconditions for transmission of D. repens and D. immitis are influenced by factors such as human behavior with respect to pets and wildlife, globalization, and climatic factors.
“The above-mentioned preconditions are themselves influenced by several factors like human behavior with respect to pets (pet travel and health care) and wildlife (e.g., high fox populations after rabies eradication programs), globalization, and climatic factors [7].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [7] R Morchón, 2012, Heartworm Disease (<italic>Dirofilaria immitis</italic>) and Their Vectors in Europe—New Distribution Trends, Front Physiol source
Not checked in the free run.
- Interpretationreasoning
The number of infected dogs might be the limiting factor for the establishment of Dirofilaria in Austria.
“The number of infected dogs might be the limiting factor for the establishment of Dirofilaria in Austria.”
Quote in the paperSubstantial claim - Interpretationreasoning
In Austria, competent mosquito vectors for the transmission of both D. repens and D. immitis are part of the Austrian Culicidae species inventory.
“In Austria, competent mosquito vectors for the transmission of both D. repens and D. immitis are part of the Austrian Culicidae species inventory.”
Quote in the paperSubstantial claim - Interpretationreasoning
D. immitis will probably become established in Austria in the near future, with regard to observations in neighboring countries, particularly Hungary and Slovakia.
“but with regard to observations in the neighboring countries (particularly Hungary and Slovakia) it will probably become established in the near future.”
Quote in the paperSubstantial claim - Premisecitation
The two most common mosquito species in Austria, Ae. vexans and the Cx. pipiens complex, may readily act as potential vectors of these pathogens.
“The two most common mosquito species in Austria, Ae. vexans and the Cx. pipiens complex, may readily act as potential vectors of these pathogens [21].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [21] I Rudolf, 2014, Zoonotic <italic>Dirofilaria repens</italic> (Nematoda: Filarioidea) in <italic>Aedes vexans</italic> mosquitoes, Czech Republic, Parasitol Res source
Not checked in the free run.
- Interpretationown data
The first findings of D. repens in mosquito vectors indicate that D. repens presumably invaded into eastern Austria in recent times.
“The first findings of D. repens in mosquito vectors indicate that D. repens presumably invaded into eastern Austria in recent times.”
Quote in the paperSubstantial claim - Interpretationown data
Until now, D. immitis in Austria is only associated with travel activity.
“Until now, D. immitis is only associated with travel activity”
Quote in the paperSubstantial claim
- May combine two claims. 10
- Classified as probably not a substantial claim. 4
May combine two claims.
Findingown dataOf the 30 human D. repens cases in Austria, 16 (53%) were in male patients and 14 (47%) in females.
“16 (53%) in male patients and 14 (47%) in females”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
Findingnone givenOccasionally, infections with D. repens in Austria were discussed to be autochthonous (one human case and seven in dogs).
“However, occasionally infections with D. repens were discussed to be autochthonous (one human case and seven in dogs).”
Quote in the paperNot a substantial claim- Rests on an assumption: Reported travel activity or its absence reliably indicates whether a Dirofilaria infection was imported or acquired autochthonously.
May combine two claims.
FindingcitationThe three suspected human pulmonary dirofilariosis patients in Austria presented pulmonary symptoms and were positive for D. immitis at serology.
“Patients presented pulmonary symptoms and were positive for D. immitis at serology.”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [19] Auer H. Die Dirofilariose des Menschen Epidemiologie and Nosologie einer gar nicht so seltenen Parasitose in Osterreich (Nematoda, Spirurida, Onchocercidae). Denisia; 2004; 463–471.
Not checked in the free run.
May combine two claims.
FindingcitationHistology and PCR for the 2006 Nickelsdorf human case were positive for D. repens and negative for D. immitis.
“Histology and PCR were positive for D. repens and gave a negative result for D. immitis.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [18] H Auer, 2008, Der erst authochthone Fall einer subkutanen Dirofilariose in Österreich, Wien Klin Wochenschr source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
Findingown dataOf the 26 D. repens monoinfections in dogs in Austria, 10 (38%) were female and 16 (62%) were male.
“Ten (38%) dogs were female and 16 were male (62%).”
Quote in the paperNot a substantial claimMay combine two claims.
Findingnone givenCases of both D. repens and D. immitis in dogs in Austria have increased in recent years.
“The increase of cases with both D. repens and D. immitis in dogs in recent years makes it clear that veterinarians should also consider these parasites in the diagnosis of Austrian dogs without prior travel activity.”
Quote in the paperSubstantial claimMay combine two claims.
PremisecitationD. repens and D. immitis have been documented more frequently in recent years, and autochthonous findings in dogs as well as mosquitoes are reported in new areas where both filarioid species were not known as endemic before.
“D. repens and D. immitis have been documented more frequently in recent years, and autochthonous findings in dogs as well as mosquitoes are reported in new areas where both filarioid species were not known as endemic before [3,7,11].”
Quote in the paperSubstantial claim0 of 3 sources checked- cites [3] F Simón, 2012, Human and animal dirofilariasis: the emergence of a zoonotic mosaic, Clin Microbiol Rev source
Not checked in the free run.
- cites [7] R Morchón, 2012, Heartworm Disease (<italic>Dirofilaria immitis</italic>) and Their Vectors in Europe—New Distribution Trends, Front Physiol source
Not checked in the free run.
- cites [11] C Genchi, 2011, Dirofilarial infections in Europe, Vector Borne Zoonotic Dis source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationIn central Europe, the first cases of D. immitis were described in four dogs in Switzerland in 1995.
“the first cases of D. immitis were described in four dogs in Switzerland in 1995 [9].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [9] P Deplazes, 1995, Endoparasitenbefall bei Findel- und Verzicht-Hunden in der Südschweiz, Schweiz Arch Tierheilkd
Not checked in the free run.
May combine two claims.
PremisecitationAedes vexans, Ae. albopictus (no stable populations in Austria in 2014), Culiseta annulata, Culex pipiens complex, Anopheles maculipennis complex, An. algeriensis, and Ochlerotatus caspius are potential vectors for D. repens.
“Of these, Aedes vexans, Ae. albopictus (no stable populations in Austria in 2014), Culiseta annulata, Culex pipiens complex, Anopheles maculipennis complex, An. algeriensis, and Ochlerotatus caspius are potential vectors for D. repens [3,12,17,21–23].”
Quote in the paperNot a substantial claim0 of 6 sources checked- cites [3] F Simón, 2012, Human and animal dirofilariasis: the emergence of a zoonotic mosaic, Clin Microbiol Rev source
Not checked in the free run.
- cites [12] E Bocková, 2013, <italic>Dirofilaria repens</italic> microfilariae in <italic>Aedes vexans</italic> mosquitoes in Slovakia, Parasitol Res source
Not checked in the free run.
- cites [17] C Zittra, 2015, Screening blood-fed mosquitoes for the diagnosis of filarioid helminths and avian malaria, Parasit Vectors source
Not checked in the free run.
- cites [21] I Rudolf, 2014, Zoonotic <italic>Dirofilaria repens</italic> (Nematoda: Filarioidea) in <italic>Aedes vexans</italic> mosquitoes, Czech Republic, Parasitol Res source
Not checked in the free run.
- cites [22] K Silbermayr, 2014, Autochthonous <italic>Dirofilaria repens</italic> in Austria, Parasit Vectors source
Not checked in the free run.
- cites [23] N Becker, 2010
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationCurrently, 46 mosquito species are known to be present in Austria.
“Currently, 46 mosquito species are known to be present in Austria [17].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [17] C Zittra, 2015, Screening blood-fed mosquitoes for the diagnosis of filarioid helminths and avian malaria, Parasit Vectors source
Not checked in the free run.
May combine two claims.
InterpretationreasoningA stable establishment of D. repens in Austria is still to be seen, because all these cases were documented within a relatively short time span.
“However, a stable establishment of D. repens is still to be seen, as all these cases were documented within a relatively short time span.”
Quote in the paperSubstantial claimMay combine two claims.
InterpretationreasoningThe circumstance that most Austrian dogs are kept indoors might delay the introduction and establishment of the nematodes and might be the reason why they are to date not autochthonous in Austria, while this is the case for neighboring countries.
“This circumstance might delay the introduction and establishment of the nematodes and might be the reason why they are to date not autochthonous in Austria, while this is the case for neighboring countries.”
Quote in the paperSubstantial claim- Rests on an assumption: Most dogs in Austria are kept in the house, and outdoor and/or kennel keeping is uncommon in Austria.
May combine two claims.
PremisecitationAccording to Simon et al. (2012), transmission of D. repens and D. immitis is limited to two main preconditions: the presence of one mosquito species capable of transmitting the parasites, and the presence of a minimum number of dogs infected with adult helminths that produce microfilariae.
“According to Simon et al. (2012), the transmission of D. repens and D. immitis is limited to two main preconditions: (i) the presence of one mosquito species capable of transmitting the parasites, and (ii) the presence of a minimum number of dogs infected with adult helminths that produce microfilariae.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites Simon et al. (2012) source
Not checked in the free run.
May combine two claims.
Interpretationown dataThe potential autochthonous findings of D. repens in one human, seven dogs, and two mosquito species indicate that D. repens is becoming endemic and establishing itself in Austria.
“The (potential) autochthonous findings of D. repens in one human, seven dogs, and two mosquito species indicate that this parasite is becoming endemic and establishing itself in Austria.”
- Also stated in: § Key Learning Points · hedged
“Autochthonous findings of D. repens in mosquitoes, as well as potential autochthonous cases in dogs and humans, suggest that this parasite is establishing itself in Austria.”
Quote in the paperSubstantial claim- Also stated in: § Key Learning Points · hedged
The paper relies on this without support.
Until very recently, both D. repens and D. immitis were nonendemic in Austria.
“Until very recently, both species were known to be nonendemic in Austria.”
The paper relies on this without support.
Reported travel activity or its absence reliably indicates whether a Dirofilaria infection was imported or acquired autochthonously.
“Twenty-seven patients reported travel activity to at least one country known to be endemic for D. repens prior to infection.”
“All potentially autochthonous cases (with no reported time spent abroad) were reported from eastern Austria (Lower Austria and Burgenland) only (Fig 2).”
The paper relies on this without support.
Detection of D. repens in mosquito vectors in Burgenland indicates local transmission and establishment of D. repens in eastern Austria.
“The first findings of D. repens in mosquito vectors indicate that D. repens presumably invaded in eastern Austria.”
The paper relies on this without support.
Climate analyses from central Europe are applicable to Austria for assessing the capacity of D. immitis to establish.
“Climate analyses from central Europe indicate that D. immitis also has the capacity to establish itself in the lowland regions of Austria, given that both canid and culicid hosts are present.”
The paper relies on this without support.
Data from Germany on D. immitis establishment are applicable to Austria.
“For D. immitis, this could not be confirmed yet, but data from Germany suggest that the successful establishment of this nematode species in Austria is a credible scenario for the near future.”
The paper relies on this without support.
Cases reported in the literature and electronic patient databases are representative of all Dirofilaria cases in Austria.
“Published as well as unpublished cases of imported and autochthonous documentations of D. repens and D. immitis in dogs (definite hosts), humans (accidental hosts), and mosquitoes (vectors) in Austria are summarized (Fig 1).”
The paper relies on this without support.
Most dogs in Austria are kept in the house, and outdoor and/or kennel keeping is uncommon in Austria.
“Most of these dogs are kept in the house; outdoor and/or kennel keeping is uncommon in this country.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
A study in Austria reported eighteen parasitized dogs with D. immitis and three with co-infections with D. repens.
“On the one hand, a study reported eighteen parasitized dogs with D. immitis and three with co-infections with D. repens [48].”
From What has happened to heartworm disease in Europe in the last 10 years? (2022) · cites this paper as [48]
One main reason for the delayed introduction and establishment of D. immitis in Austria is the lack of microfilaraemic dogs as a consequence of less common kennelling or outdoor keeping of dogs in Austria.
“One main reason for the delayed introduction and establishment of D. immitis is the lack of microfilaraemic dogs as a consequence of less common kennelling or outdoor keeping of dogs in Austria [6].”
From First Autochthonous Infection of a Cat with Dirofilaria immitis in Austria (2021) · cites this paper as [6]
Austria is facing pre-endemic status due to the worldwide spreading of D. immitis.
“The spreading of D. immitis worldwide due to climate change, globalization and increased travel of infected dogs is the reason Austria is facing the pre-endemic status [5,6].”
From First Autochthonous Infection of a Cat with Dirofilaria immitis in Austria (2021) · cites this paper as [6]
The ongoing north- and eastward expansion of both Dirofilaria species has been mainly attributed to global warming, as well as environmental changes, which promote the expansion of mosquito vectors, along with the increased international mobility of infected vertebrates.
“Such expansion has been mainly attributed to global warming, as well as environmental changes, which promote the expansion of mosquito vectors, along with the increased international mobility of infected vertebrates [27, 39–41]”
From Molecular characterization of Dirofilaria spp. circulating in Portugal (2017) · cites this paper as [41]
Autochthonous D. repens infections have been found in Austria in mosquitoes, dogs, and humans.
“The first autochthonous findings of D. repens in mosquitoes in Austria were made in 2012, and seven cases of cutaneous dirofilariosis in dogs were thought to be autochthonous infections until 2014, while the first autochthonous D. repens infection in humans was found even earlier, in 2006 [9,10,11].”
From The Incidence of Dirofilaria immitis in Shelter Dogs and Mosquitoes in Austria (2021) · cites this paper as [9]
In Austria, the endemisation of D. repens already appears to be concluded and could be considered a model for the expected future distribution of D. immitis, as the heartworm seems to be spreading mainly to the areas where D. repens has already established itself.
“In Austria, the endemisation of D. repens already appears to be concluded and could be considered a model for the expected future distribution of D. immitis, as the heartworm seems to be spreading mainly to the areas where D. repens has already established itself [1,4,8,9].”
From The Incidence of Dirofilaria immitis in Shelter Dogs and Mosquitoes in Austria (2021) · cites this paper as [9]
Several mosquito species known to be competent vectors for D. immitis and D. repens are present in Austria.
“Several mosquito species known to be competent vectors for D. immitis and D. repens are present in Austria (Fuehrer et al. 2016).”
From Current trends in canine dirofilariosis in Austria-do we face a pre-endemic status? (2020) · cites this paper as Fuehrer et al. 2016
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.”
From Current trends in canine dirofilariosis in Austria-do we face a pre-endemic status? (2020) · cites this paper as Fuehrer et al. 2016
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.”
From Current trends in canine dirofilariosis in Austria-do we face a pre-endemic status? (2020) · cites this paper as Fuehrer et al. 2016
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).”
From Current trends in canine dirofilariosis in Austria-do we face a pre-endemic status? (2020) · cites this paper as Fuehrer et al. 2016
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).”
From Current trends in canine dirofilariosis in Austria-do we face a pre-endemic status? (2020) · cites this paper as Fuehrer et al. 2016
From 1978 to 2014, 33 cases of human dirofilariasis caused by D. repens were reported in Austria (30 cases), and three cases caused by D. immitis, rising to a total of 39 cases in 2020.
“From 1978 to 2014, 33 cases of human dirofilariasis caused by D. repens were reported in Austria (30 cases), and three cases caused by D. immitis, rising to a total of 39 cases in 2020”
From Dirofilaria spp. and Angiostrongylus vasorum: current risk of spreading in Central and Northern Europe. (2021) · cites this paper as [62]
Over the past four decades, incidence of human dirofilariasis in Austria has markedly increased, particularly after 1998.
“Over the past four decades, incidence has markedly increased, particularly after 1998”
From Dirofilaria spp. and Angiostrongylus vasorum: current risk of spreading in Central and Northern Europe. (2021) · cites this paper as [62]
A review reported 37 dogs with D. repens infection and 25 dogs with D. immitis infection in Austria till 2014, a total of 62 cases within 18 years.
“a review on canine and human dirofilarial cases in Austria reported 37 dogs with D. repens infection (including the seven possibly autochthonous infections) and 25 dogs with D. immitis infection till 2014—a total of 62 cases within 18 years”
From Dirofilaria spp. and Angiostrongylus vasorum: current risk of spreading in Central and Northern Europe. (2021) · cites this paper as [62]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Conclusion denies autochthonous nematodes despite confirmed mosquito findings
MinorThe conclusion says the nematodes are not autochthonous in Austria, whereas the mosquito section explicitly describes autochthonous Dirofilaria findings there.
“This circumstance might delay the introduction and establishment of the nematodes and might be the reason why they are to date not autochthonous in Austria, while this is the case for neighboring countries.”
“To date, these are the only findings of autochthonous Dirofilaria spp. in mosquitoes in Austria.”
The citation lists haven’t been fetched yet
References 37 · Cited by 100
Research works printed but not linked: 5
- H Bardach, 1981, Subkutane <italic>Dirofilaria (Nochtiella) repens</italic>-Infektion beim Menschen—Erste Fallbeschreibung in Österreich und Übersicht der Literatur, Wien Klin Wochenschr, 93, 123
- S Schuller-Petrovic, 1996, Subkutane Dirofilariose beim Menschen—Ein Fallbericht aus Österreich, H+G Zeitschrift fur Hautkrankheiten, 71, 927
- H Auer, 1997, Ein seltener Fall einer <italic>Dirofilaria repens</italic>-Infestation des Nebenhodens, Mitt Osterr Ges Tropenmed Parasitol, 19, 53
- M Kleiter, 2001, Kutane Dirofilariose (<italic>Dirofilaria repens</italic>) bei zwei nach Österreich importierten Hunden, Kleintierpraxis, 46, 283
- M Löwenstein, 1988, <italic>Dirofilaria immitis</italic> infection of dogs in Austria, Wien Tierarztl Monatsschr, 75, 420
- Authors
- Fuehrer, H.-P., Auer, H., Leschnik, M., Silbermayr, K., Duscher, G., & Joachim, A.
- Affiliations
- University of Veterinary Medicine Vienna (AT)
- Medical University of Vienna (AT)
- Corresponding author
- Fuehrer, Hans-Peter
- Venue
- PLOS Neglected Tropical Diseases
- Publisher
- Public Library of Science (PLoS)
- Published
- 2016-05-19
- Volume
- 10
- Issue
- 5
- Pages
- e0004547
- ISSN
- 1935-2727 (ISSN-L)
- 1935-2735
- PMC
- PMC4873239
- OpenAlex
- W2406934330
- Cited by
- 100
- References
- 37
- Citations by year
- 2026: 7 · 2025: 11 · 2024: 7 · 2023: 5 · 2022: 12 · 2021: 15 · 2020: 11 · 2019: 6 · 2018: 12 · 2017: 13 · 2016: 1
- FWCI
- 1.64
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- PLoS neglected tropical diseases (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- Biodiversa+
- Deutsche Forschungsgemeinschaft (KL 2087/6-1, ANR-13-EBID-0007-01, I-1437)
- Agence Nationale de la Recherche (ANR-13-EBID-0007, I-1437, KL 2087/6-1)
- Austrian Science Fund (KL 2087/6-1, I1437, FWF I-1437, ANR-13-EBID-0007-01)
- Topics
- Health Sciences › Medicine › Infectious Diseases › Parasitic Diseases Research and Treatment
- Health Sciences › Veterinary › Small Animals › Helminth infection and control
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Research on Leishmaniasis Studies
- Keywords
- Dirofilaria repens, Dirofilaria immitis, canine dirofilariasis, invasive species, autochthonous infection, mosquito vectors, climate change, Burgenland, Austria
- MeSH terms
- Animals, Austria, Dirofilaria immitis, Dirofilariasis, Dog Diseases, Dogs, Europe, Germany, Humans, Insect Vectors, Culicidae, Zoonoses, Endemic Diseases, Host-Pathogen Interactions, Climate Change, Dirofilaria repens
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