Local outbreak of spontaneous pneumothorax secondary to paragonimosis in southwestern Ontario dogs

Three dogs were diagnosed with spontaneous pneumothorax and referred to the Ontario Veterinary College Health Sciences Centre for management. The 3 dogs were diagnosed with secondary spontaneous pneumothorax due to paragonimosis. The diagnosis was made by visualization of adult trematodes during surgical exploration with histopathological confirmation in 1 dog, and detection of trematode eggs via fecal sedimentation in the other 2 dogs. Two of the dogs developed unusual additional lesions, including hemoabdomen, muscle abscess, and abdominal adhesions. These were suspected to be secondary to aberrant fluke larval migration. All 3 dogs lived within a relatively small geographical area of Ontario and were hospitalized between December 2021 and March 2022. Each dog survived to discharge with surgical or medical management of the pneumothorax and treatment with a prolonged course of fenbendazole. Key clinical message: Paragonimosis should be considered as a differential diagnosis for canine spontaneous pneumothorax in areas where Paragonimus kellicotti is, or may be, endemic, or in dogs that have travelled to endemic areas - particularly if the patient has a history of cough or potential exposure to freshwater crayfish. Routine anthelmintic treatment does not prevent infection and standard fecal floatation methods may not detect the eggs. Therefore, diagnostic testing should include a fecal sedimentation test and thoracic radiographs to screen for P. kellicotti.

Description of a new lung fluke species, Paragonimus vietnamensis sp. nov. (Trematoda, Paragonimidae), found in northern Vietnam

Based on morphology of metacercariae and adult worms together with molecular data from our previous study, we describe herein a new lung fluke species named Paragonimus vietnamensis sp. nov. Metacercariae of this new species is round and extremely large in size (nearly 800 mum in diameter) having a fragile outer cyst of variable thickness and a thin fragile inner cyst. There are little or no space between metacercaria and the inner cyst wall. These and other morphological features of metacercariae of P. vietnamensis sp. nov. are not completely identical with but have some similarities with those of P. microrchis, P. proliferus, or P. menglaensis. On the other hand, adult worms obtained by experimental infection of these large metacercariae are oval in shape, having a ventral sucker slightly larger than the oral one, and having singly arranged relatively short cuticular spines. These morphological features of adult worms are partly similar to but not identical with those of P. microrchis, P. skrjabini, P. yunnanenis, P. xiangshanensis, or P. harinasutai. Taken these morphological data and our previous molecular phylogenetic analyses of ITS2 and CO1 sequences of metacercariae and adult worms together, P. vietnamensis sp. nov. is different from any other known Paragonimus spp.

Possible discovery of Chinese lung fluke, Paragonimus skrjabini in Manipur, India

To obtain more information about Paragonimus species prevalent in Manipur, India, hundreds of freshwater crabs, Potamiscus manipurensis, were captured from mountain streams in the Motbung Mountains in Senapati District, from December 1997 to January 1998. Crab extracts were prepared by digestion, differential filtration, and sedimentation. The filtered sediments were critically examined under a stereomicroscope. Isolated Paragonimus metacercariae were used for morphological study and animal experimentation. Forty-seven metacercariae were fed orally to a 3-month-old male puppy of local breed; at autopsy 155 days after inoculation, 12 adult worms were recovered; 2 were free in the thoracic cavity and 5 pairs were in lung cysts. Two adult worms were flattened and fixed in 70% ethanol and the remaining worms were put directly into 70% ethanol and preserved until July 2005. The former 2 worms were stained with borax carmine for morphological study at Sikkim Manipal Institute of Medical Sciences, Sikkim, India. Two adult worms in the latter group were sent to the National Institute of Infectious Diseases, Tokyo, Japan, for morphological identification and DNA sequencing. The morphological features of the borax carmine-stained worms were characteristic of P. skrjabini, although no genetic material for PCR amplification and sequencing could be extracted from the worm.

Detection of Paragonimus heterotremus eggs in experimentally infected cats by a polymerase chain reaction-based method

A polymerase chain reaction (PCR) procedure for the detection of Paragonimus heterotremus eggs in stool samples was developed and compared with Stoll's egg count method. The primers were designed on the basis of a previously constructed pPH-13-specific DNA probe, which produced an approximate 0.5-kb amplified product. This PCR method could detect as few as 5 eggs in 0.6 g of artificially inoculated feces of a healthy control cat or as little as 1 x 10(-4) ng of P. heterotremus genomic DNA. The assay had 100% sensitivity in all infected cats. The method did not yield an approximate 0.5-kb product with DNA from other parasites such as Gnathostoma spinigerum, Trichinella spiralis, Fasciola gigantica, Echinostoma malayanum, Opisthorchis viverrini, Dirofilaria immitis, and Taenia saginata; exceptions were Paragonimus siamensis and Paragonimus westermani. In addition, no genomic DNA from Escherichia coli, Burkholderia pseudomallei, Acinetobacter anitratus, Mycobacterium tuberculosis, Staphylococcus aureus, beta-Streptococcus grA, and Proteus mirabilis or from the vertebrate and invertebrate hosts of P. heterotremus was amplified in the PCR assay. This assay has great potential for application in clinical epidemiological studies.

Identities of two Paragonimus species from Sri Lanka inferred from molecular sequences

Metacercariae of Paragonimus spp. were obtained from field-collected freshwater crabs in Sri Lanka. Genomic DNA was extracted from single metacercariae. Two gene regions (partial mitochondrial cytochrome c oxidase subunit 1 (CO1) and the second internal transcribed spacer of the nuclear ribosomal gene repeat (ITS2)) were amplified using the polymerase chain reaction. Two differing sequences were obtained for each of these gene regions. Phylogenetic analyses placed the type 1 sequences as sister to a clade containing P. westermani and P. siamensis whereas the type 2 sequences were close to published sequences of P. siamensis from Thailand. The possible taxonomic status of these two types are discussed. This is the first report of molecular data about Paragonimus from Sri Lanka.

Epidemiology, symptoms and treatment of paragonimiasis in Sin Ho district, Lai Chau province, Vietnam

Sin Ho is a district of the northern mountainous province of Lai Chau, Vietnam, where the people have the habit of eating undercooked crabs. A study on paragoniamiasis carried out from 1994 to 1995 with 1,642 persons in this endemic area, showed that the rate of eating raw-crab was 72.5%. Crab examination (Ranguna kimboiensis) showed an infection rate of Paragonimus metacercaria of 98.1%. With 624 stool samples examined by Kato technique, the infection rate of Paragonimus in humans was 6.4%. With 338 sputum samples examined by direct and centrifuge methods, the infection rate of Paragonimus was 7.4%. Most of the patients were children (63.2%). The infection rate of Paragonimus in dogs was 18.2 - 33.3%. Adult worms, collected from the dogs in the field and from the cats in laboratory, were identified as Paragonimus heterotremus. The main symptoms of Paragonimus patients were cough and hemoptysis (92%), discontinuously developed (96%), without fever (94%), chest pain (70%), pleural effusion (26%), neurogical symptoms (8%), eosinophilia (88.9%), nodular ring shadows in the lungs, as shown by chest X-ray examination and more in lower lobe, (76.2%). Paragonimiasis patients were treated by (a) Praziquantel 25 mg/kg/day x 3 days; the cure rate was 68.8%. (b) Praziquantel 50 mg/kg/day x 3 days; the cure rate was 75%.

Identification of African Paragonimidae by multivariate analysis of the eggs

A study of metacercariae and adult Paragonimidae revealed the existence in West-Africa of four species, of which two are largely recorded in literature (Paragonimus africanus and Paragonimus uterobilateralis), one was suspected (Paragonimnus westermani-like) and one remained unrecorded in Africa (Euparagonimus sp). Among the two last ones, P. westermani-like was probably confused with P. africanus, and Euparagonimus sp. with P. uterobilateralis. P. westermani-like adult worms differed from P. africanus by the morphology of ovary, testes and the size of the metraterm eggs. Euparagonimus could be identified by a short excretory bladder in metacercariae. The discriminant functions established on eggs measurements (average, maximum and minimum length, average, maximum and minimum width) were able to separate the isolates into four groups. The largest eggs (97 x 59 microm) belonged to P. westermani-like, the medium sized eggs were ascribed to P. africanus (91 x 49 microm) and to Euparagonimus sp. (84 x 50 microm), and the smaller eggs (69 x 42 microm) were identified as P. uterobilateralis. Three Paragonimidae were identified in Cameroon: P. westermani-like, P. africanus and Euparagonimus sp. Additionally, P. uterobilateralis, P. westermani-like, and Euparagonimus sp. were found in the Congo, Gabon, and the Ivory Coast, respectively.

Egg production capacity of Paragonimus pulmonalis in cats

In the present study, each of 43 cats was fed with a single metacercaria of Paragonimus pulmonalis and 2 cats (controls) with 2 metacercariae. They were killed 22-372 days postinfection. In the test group, 18 (41.9%) cats were infected, as well as the 2 cats in the control group. Among the 18 worms recovered from the test group, 9 found in the lungs were mature, whereas 5 mature and 4 immature worms were in the pleural cavity. Most eggs from worms encased in a cyst were passed in the feces. However, eggs from worms in the pleural cavity were only found on the lung surface and pleural cavity. Mature worms in cysts seemed to exhibit higher egg production capacity than those in the pleural cavity. Paired mature worms from a cyst laid more eggs than a single encysted mature worm in vitro at room temperature.

Paragonimiasis in Sin Ho District, Lai Chau Province, Viet Nam

Forty-four cases of pulmonary paragonimiasis, two also with evidence of cerebral infection, were found in Sin Ho District in Northern Viet Nam. There were 30 males and 14 females, 2-30 years of age. The diagnosis was made by sputum examination. Pet dogs and wild dogs in the area were also found infected and the people often eat roasted crabs.

A case of paragonimiasis in a civet cat with a new Paragonimus sub species in Manipur, India

A case of paragonimiasis in a civet cat with a new Paragonimus sub species in Manipur, India.

[Endemic area of paragonimiasis in Vietnam]

We studied 155 patients with chronic pulmonary disease from a mountainous area in north-west Vietnam, in March, 1993. Sputum was collected from patients and examined for the presence of Paragonimus eggs using a light microscope. Forty four of the patients (approximately 28%) were diagnosed with and treated for human paragonimiasis. Forty two of these cases were purely pleural-pulmonary forms whereas the remaining two cases also involved problems with the central nervous system. Most of the patients had eaten freshwater crabs (Ranguna luangprabangensis) which had been insufficiently cooked. This appears to be the main source of infection as these crustaceans are often highly contaminated with metacercariae. Most of the patients were children (aged 11 +/- 5 years) and male (30 of the 44). Sputum samples were also collected from 225 healthy people from the same area during the period March 1993 to April 1996. The samples were examined using a light microscope and 11 (approximately 5%) were found to contain Paragonimus eggs. A number of animals were also tested. Three pet dogs (of 14 tested), 2 wild dogs (of 2 tested) and 2 domestic pigs (of 15 tested) were found to be infected with the fluke. This is the first report of an area with endemic paragonimiasis in Vietnam. Human infections probably also occur in other areas. They are a threat to public health and may be confused with tuberculosis.

[The biology of Paragonimus westermani ichunensis in the Maritime Territory. Experimental research]

It has been experimentally found that larval and pulmonary paragonimiasis types are caused by the trematode Paragonimus westermani ichunensis. The development of either paragonimiasis in nontypical definitive hosts depends on the stage of larval development when they penetrate into the mammal. Only the P. westermani ichunensis trematode is likely to develop with the participation of Juga mollusks on the territory of the Primorye.

Studies on host specificity in Paragonimus westermani: ultrastructural study of inflammatory reactions to the parasite in rat muscles

Inflammatory reactions to the lung fluke, Paragonimus westermani, in an abnormal host, the rat, were studied by electron microscopy. Inflammatory cells accumulated around the worms in rat muscles, but the reaction varied significantly in intensity as well as distribution of inflammatory cells from worm to worm in the same and different hosts. In an accumulation of inflammatory infiltrates around the worm, eosinophils were more commonly seen, and neutrophils and macrophages were fewer in number. Mast cells appeared rarely. Where inflammatory cells touched to the worms, the tegument of the worms was covered with moderately electron-dense flocculent material which included dense granules. This material, which probably consisted of immune complexes of host antibody and antigen secreted from tegumental granules, seemed to block the inflammatory cells from adhering to the worm surfaces. Inflammatory cells made direct contact with worm surfaces where flocculent material was absent. Dense secretory material was discharged from some eosinophils as a result of degranulation.

Evaluation of praziquantel for treatment of experimentally induced paragonimiasis in dogs and cats

Praziquantel was used successfully for treatment of a small number of dogs and 1 cat infected with Paragonimus kellicotti. To further evaluate the usefulness of this drug in treating such infections, 7 cats and 7 dogs were inoculated orally with metacercariae (12 and 20 to 22, respectively) obtained from crayfish, then were treated after the infections became patent; 2 cats and 2 dogs served as noninfected controls. Beginning 1 week before infection, and continuing weekly thereafter, physical, hematologic, and fecal examinations were performed on each animal; thoracic radiography was performed every other week. By postinoculation week 6, all dogs given metacercariae had patent infection diagnosed on the basis of positive results of fecal examination. By postinoculation week 7, 5 cats had confirmed patent infection, but 2 cats given metacercariae never had patent infection or had signs of infection. Clinical signs of infection were minor and included increased respiratory tract noise, slight inducible cough, or mild dyspnea. Transient eosinophilia was detected in dogs around postinoculation week 3. Pretreatment radiography revealed cavitated lesions in cats only; pleural lines and patchy infiltrates in cats and dogs; or pneumothorax in dogs only. The treatment regimen consisted of 23 mg of praziquantel/kg of body weight given every 8 hours for 3 days; 1 infected cat and dog were not treated. By 11 days after treatment, eggs had disappeared from the feces of infected animals, and marked resolution of lung lesions was evident radiographically.(ABSTRACT TRUNCATED AT 250 WORDS)

Lesions associated with pulmonary parasites in bobcats (Felis rufus) from Arkansas

Two of five bobcats (Felis rufus) from southwestern Arkansas had natural pulmonary infections of Paragonimus kellicotti and Filaroides rostratus. Pairs of P. kellicotti were found in spherical cyst-like structures approximately 1 cm in diameter. Filaroides rostratus were seen as serpentine pale white areas on the pleural surface and also firmly embedded in fibrous capsules in the pulmonary parenchyma. Histologic lesions associated with the presence of these parasites consisted primarily of a verminous bronchitis. Clinical signs or compromised pulmonary function were not associated with these infections.

Studies on host specificity in Paragonimus westermani: I. Ultrastructural characterization of metacercariae and juvenile and adult worms from abnormal and definitive hosts

Comparative ultrastructural studies have been made of newly excysted metacercariae and worms recovered from abnormal (rats) and normal definitive hosts (dogs). Worms from rats survived for prolonged periods without any growth or development in muscles of the host. They appeared to resemble metacercariae in general features, although ultrastructural observations revealed differences in the composition of tegumental granules and the development of the excretory bladder and caeca. Worms from dogs showed well-developed morphology in association with active energy metabolism and biosynthesis.

Parasitic pneumonia in a dog caused by a lung fluke of the genus Paragonimus

Post mortem examination of a dog that died after a spell of respiratory distress revealed about 20 randomly distributed cystic lesions in the lungs. Those examined each harboured 2 light-brownish conical flukes approximately 10 mm in length. Histopathological examination of such a lesion revealed the presence of Paragonimus (lung fluke) embedded in it. The parasite had a typical spiny integument as well as other characteristics typical for the genus. Typical pigmented operculated eggs were embedded in the surrounding tissues. The life cycle of the parasite is briefly discussed.

Aplastic anemia associated with trimethoprim-sulfadiazine and fenbendazole administration in a dog

A dog that was treated with trimethoprim-sulfadiazine and fenbendazole developed transient aplastic anemia. The onset of bone marrow aplasia at 14 days after initiation of treatment and remission of it after cessation of treatment suggested that the aplasia was drug-induced. A hematologically normal dog treated with the same drug combination failed to develop hematologic dyscrasia. Because of the potential toxic effects of trimethoprim-sulfadiazine and/or fenbendazole, animals under treatment with this combination should be monitored by use of periodic CBC.

Parasites of the respiratory tract

The author discusses the parasites that infect the nasal passages, trachea, bronchi, and lung parenchyma of dogs and cats. The clinical signs, diagnosis, epidemiology, treatment, and control of infection are also considered.

Paragonimiasis in a dog: treatment with praziquantel

Oral administration of 25 mg of praziquantel/kg of body weight 3 times a day for 2 consecutive days resulted in clinical and parasitologic cure of paragonimiasis in a dog. Previous treatment with the drug at the dosage recommended for cestode removal (5 mg/kg, SC) for 2 days was only partially effective. The dog exhibited cachexia, coughing, gagging, and occasional hemoptysis. Radiography revealed nodular and cystic densities in the lungs. The life history and clinical aspects of Paragonimus kellicotti infection in the dog are briefly reviewed.

Paragonimiasis: treatment with praziquantel in 40 human cases and in 1 cat

40 patients infected with P. westermani were divided into 3 groups and treated with praziquantel (2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a]++ +isoquinolin- 4-one) by 3 different dosages. Parasitological cure was achieved in 27/40 patients, i.e. 67.5%. Details are given in this short communication.

Humoral immune response of cats to Paragonimus infection

The time course of humoral immune response to Paragonimus siamensis was studied in 10 cats experimentally infected with either 30 or 60 matacercariae and the antibody produced was detected by enzyme linked immunosorbent assay (ELISA), complement fixation test (CFT), and immunoelectrophoresis (IEP) test. With ELISA and CFT, antibodies was detected as early as 2nd week after infection and the cats remained positive throughout the 12 week period of observation. In contrast, the IEP test was persistently negative. With respect to sensitivity, both ELISA and CFT are equally sensitive but the mean ELISA titer was consistently higher than that of CFT. THe magnitude of the antibody response appeared to be related to duration of the infection but not to the infective dose and the number of worms recovered. There was variability in titers among cats infected with equal numbers of metacercariae. The tests can not be used for differential diagnosis of infections by P. siamensis and P. heterotremus because of the cross-reaction. Such cross-reaction did not not occur against unrelated parasites including hookworm. Toxocara cati and Spirometra mansoni.

[A new lung fluke from the coastal range of ecuador: Paragonimus ecuadoriensis n.sp. (paragonimidae, trematoda) (author's transl)]

P. ecuadoriensis in the first lung fluke described from Ecuador. The description is based on 10 adult flukes from a natural infected Coati (Nasua nasua), 23 adults from 2 experimentally infected cats, and 200 metacercariae from the second intermediate host, the freshwater crab Hypolobocera aequatorialis. The new species is characterized by the following features: mouth succer larger than acetabulum or nearly of the same size; integument spines ("cuticular" spines) single; ovary with 5-6 short branches, which divide into more or less short broad lobes; testes larger than ovary with 5-6 simple or polymorphic lobes; eggs longish-ovoid, shell thin and uniform in thickness; surface undulated. Metacercariae not encysted. The adults of the new species are differentiated from probably related lung flukes P. peruvianus, P. mexicanus, and P. inca by the different morphology of ovary and testes, and by the size and form of the eggs. The metacercariae of P. ecuadoriensis are located not only in the hepatopancreas of the crab host - as it is in the case of P. peruvianus - but also and more frequently in the musculature. Paragonimus-eggs from sputum of two patients show partly the same characteristics as the eggs from animal hosts. One may therefore assume that P. ecuadoriensis is infecting humans in the investigated area.

Fenbendazole for treatment of Paragonimus kellicotti infection in dogs

The effect of fenbendazole therapy was studied in 9 dogs with pulmonary paragonimiasis induced by inoculation of metacercariae (25/dog) of Paragonimus kellicotti. At 42 to 47 days after 6 dogs were inoculated, they were given fenbendazole in 2 divided doses totaling 50 mg (4 dogs) or 100 mg (2 dogs)/kg of body weight each day for 10 to 14 days. Three dogs were not treated. The passage of Paragonimus eggs in the feces ceased after 3 days at the high dosage and after 3 to 8 days at the low dosage. All dogs were euthanatized and necropsied on day 14. Live flukes were not recovered from the lungs of any treated dog, but 15, 19, and 23 live flukes were recovered from the untreated dogs.

The life cycle of Paragonimus kellicotti in cats

Migration and development of Paragonimus kellicotti were studied in cats killed between 1 and 265 days after feeding 15--20 metacercariae from the hearts of naturally infected crayfish. Metacercariae excysted in the intestine and appeared in the peritoneal cavity within 24 hr. Some young flukes penetrated the diaphragm and migrated to the pleural cavity during the first week, but the majority penetrated the pleura between 10 and 14 days. No flukes were found in the pleural cavity after 23 days postinfection. By 4 weeks postinfection, the flukes were well established within lung parenchyma, mainly in the right caudal lobe, where most of their growth occurred. Eggs first were seen in flukes on the 34th day postinfection and in feces 2 days later. Estimated daily ova production ranged from 1,000 to 2,000 eggs/fluke/day.

Pathogenesis of experimental pulmonary paragonimiasis in cats

Specific-pathogen-free cats (n = 20) were inoculated orally with metacercariae of Paragonimus kellicotti and necropsied between 1 and 263 days later. The immature Paragonimus flukes excysted in the intestine, penetrated the intestinal wall, and migrated from the peritoneal cavity through the diaphragm to the pleural surface of lungs by postinoculation days (PID) 5 to 23. This migration resulted in multifocal eosinophilic peritonitis and myositis. The flukes entered the lung by penetration of the pleura, which resulted in multifocal pleural hemorrhage and eosinophilic pleuritis. Immature flukes developed in the subpleural alveolar tissue surrounded by intense eosinophilic and neutrophilic inflammation. Communications developed between the fluke-containing subpleural cavities and adjacent bronchioles by PID 39, and ova from the sexually mature flukes entered the bronchioles. From PID 55 to 263, other prominent pulmonary lesions were peribronchiolar infiltration of lymphocytes and plasma cells, hyperplasia of bronchioles and peribronchiolar glands, and chronic active eosinophilic granulomatous pneumonia associated with degenerating Paragonimus ova in the alveolar tissue adjacent to cysts. The interior surface of the fluke-containing cysts became partially epithelialized by cells from communicating bronchioles.

Induced paragonimiasis in cats: clinical signs and diagnosis

Twenty-eight specific-pathogen-free cats were inoculated with 14 to 50 metacercariae of Paragonimus kellicotti obtained from the hearts of naturally infected crayfish. Young flukes excysted in the intestine of cats and appeared in the peritoneal cavity from 1 to 14 days after inoculation (DAI) and in the pleural cavity from 5 to 23 DAI. Flukes penetrated the pulmonary parenchyma and formed hemorrhagic subpleural lesions within 5 weeks after inoculation. Marked eosinophilia developed between 2 and 12 weeks after inoculation. Fluke-containing pulmonary lesions were detected by radiography 3 to 4 weeks after inoculation. Lesions developed most frequently in the right caudal lung lobe. Clinical signs were mild and did not appear until 4 weeks after inoculation. Thereafter, cats appeared dull and coughed intermittently. One cat became dyspneic due to pneumothorax. Paragonimus eggs were first detected at the 34th DAI, using a fecal sedimentation technique.

Paragonimus westermanni in tigers (Panthera tigris) in India

Paragonimus westermanni was found in the lungs of two young tigers (Panthera tigris). Cysts were focally distributed in the lungs, initiating an emphysematous response together with extensive fibrosis in the vicinity of the cysts.

Albendazole therapy for experimentally induced Paragonimus kellicotti infection in cats

The effect of albendazole therapy was studied in 6 cats with pulmonary paragonimiasis induced by experimental inoculation of metacercariae (25/cat) of Paragonimus kellicotti. At 76 to 101 days after they were inoculated, 5 cats were administered an oral aqueous suspension of albendazole in 2 divided doses totaling 20 mg (2 cats), 50 mg (1 cat), or 100 mg (2 cats)/kg of body weight each day for 14 to 21 days. The 6th cat (control) was not administered albendazole. Nine days after cats were given the 50- and 100-mg/kg dosages, Paragonimus ova were not seen in the feces of 3 cats. There was marked reduction in ova production in the feces of the 2 cats administered 20 mg/kg of albendazole. Live flukes were not recovered from the lungs of 3 cats necropsied 4 or 5 weeks after dosing with 50 or 100 mg/kg, but the lungs of the 2 cats administered 20 mg of albendazole/kg yielded 9 and 7 apparently viable flukes. Seventeen live flukes were recovered from the control cat not treated with albendazole. In 4 noninoculated normal cats administered 20 mg (1 cat), 100 mg (1 cat), and 200 mg (2 cats) of albendazole/kg of body weight each day for 14 days, there were no gross or microscopic lesions attributable to the drug.

Paragonimus westermani in Malaysian Felidae and Viverridae: probable modes of transmission in relation to host feeding habits

Examination of naturally infected felids and viverrids in Malaysia confirmed previously published records which indicated that P. westermani occurred only in felid cats. Felis planiceps and F. temnickli were reported as new host records. Analysis of stomach contents revealed no crab remains in either family of cats, but confirmed that felids were strictly carnivorous while viverrids were often omnivorous. In feeding experiments, only viverrids ate the host crabs Potomiscus johorensis and Parathelphusa maculata. The probable transmission of P. westermani to felids via paratenic hosts was discussed.

Studies on the migratory route of Paragonimus siamensis in the bandicoot (Bandicota indica)

The migration route and the development of P. siamensis obtained from S. juliae and S. germaini were studied in B. indica. The infection rates of P. siamensis in these 2 species of crabs were 19.7% and 21.4% respectively. Worms were recovered in the abdominal cavity, pleural cavity and lungs on day 12, 16 and 30 respectively after oral infection. Worms became mature and laid eggs on day 47 after infection, but their size still increased considerably. The average egg output was found to be 144 eggs/gm faeces/worm or 443 eggs/day/worm. The average recovery rate of P. siamensis in the experimental B. indica was 15%.

Paragonimus kellicotti infection in wild carnivores in southwestern Ontario: II. Histopathologic features

Pulmonary lesions associated with naturally acquired Paragonimus kellicotti infection were studied in mink (Mustela vison), striped skunks (Mephitis mephitis), red foxes (Vulpes vulpes) and a coyote (Canis latrans). In ,ink a fibrous capsule was formed around mature flukes in dilated bronchioles or bronchi, and there was mild focal interstitial pneumonitis adjacent to fluke eggs in alveoli and migrating parasites. A thick wall, infiltrated heavily with mononuclear cells and eosinophils, surrounded mature P. kellicotti in skunks and an extensive inflammatory reaction was found around fluke eggs. In red foxes the wall was thin, hemorrhagic and contained little collagen; necrosis was associated with migrating parasites. Thick capsules formed by marked fibroplastic changes in the lamina propria of affected bronchi were found in the coyote. In raccoons with pleural adhesions massive fibroplasia with eosinophil infiltration beneath the pulmonary pleura suggested a reaction to a migrating parasite entering the lung from the thoracic cavity. It was thought that immature P. kellicotti may have caused the lesion.

A primate, Mandrillus leucophaeus, as natural host of the African lung flukeParagonimus africanus in West-Cameroon

Paragonimus africanus was recovered from a free-living drill (Mandrillus leucophaeus) in Cameroon. This is the first record on the natural infection of a non-human primate with lung flukes in Africa.