[Investigation of the population diversity of intermediate host snails and crabs of Paragonimus along Jiulong River, Zhangjiang River and Dongxi River basins in southern Fujian Province].

OBJECTIVE: To investigate the population distribution of intermediate host snails and crabs of Paragonimus along the Jiulongjiang River, Zhangjiang River, and Dongxi River basins in Bopingling Mountain, southern Fujian Province, so as to provide baseline data for researches on parasitic disease prevention and control and enlargement of samples in the parasitic resource bank. METHODS: A total of 23 villages in 8 counties (districts) along the Jiulong River, Zhangjiang River, and Dongxi River basins in Zhangzhou City, Fujian Province were selected as survey sites during the period from November 2020 through March 2023, and snail and freshwater crabs were sampled from 1 to 3 streams and ditches neighboring residential areas in each village. Morphological identification of snails was performed according to the external morphological characteristics of collected snail shells, and the unidentified snail species sampled from the natural foci of paragonimiasis in Yunxiao County were subjected to se-quence analysis of the mitochondrial cytochrome oxidase 1 (CO1) gene. The crab species was identified by observing the morphological characteristics of the terminal segment of the first pleopod of male crabs, and Paragonimus cercariae and metacercariae were detected in collected snails. RESULTS: The shells of the unidentified snails sampled from the natural foci of paragonimiasis in Yunxiao County were approximately 50 mm in height and 18 mm in width, thick and solid, long tower cone-shaped, and had 8 to 10 whorls. CO1 gene sequence analysis identified the snail species as Sulcospira hainanensis. A total of 6 freshwater snail species belonging to 5 genera within 3 families, identified 23 survey sites, including Semisulcospira libertina, Paludomus zhangchouensis and S. hainanensis that belonged to the Family Pleurceridae, Tricula fujianensis and T. huaanensis that belonged to the subfamily Triculinae, Family Pomatiopsidae, and Melanoides tuberculata (Family Thiaridae), and 11 species of freshwater crabs belonging to 5 genera within 2 families were identified, including Sinopotamon genus of S. jianglense, S. pinheense, and S. zhangzhouense, Huananpotamon genus of H. planopodum and H. zhangzhouense, Nanhaipotamon genus of N. huaanense and N. longhaiense, and Minpotamon genus of M. nasicum and M. auritum that belonged to the Family Potamidae, and Somanniathelphusa genus of S. huaanensis and S. zhangpuensis (Family Parathelphusidae). In addition, the prevalence of P. westermani cercariae infections was 0.08% (2/2 317) in P. zhangchouensis from Danyan Village in Changtai District and 0.09% (1/1 039) in S. hainanensis from Jinkeng Village in Yunxiao County, and the prevalence of P. westermani metacercariae infections was 25.81% (8/31) in S. jianglense from Danyan Village in Changtai District, and 26.31% (5/19) in S. zhangzhouense from Jinkeng Village in Yunxiao County, respectively. CONCLUSIONS: There is a population diversity in the intermediate host snails and crabs along the Jiulongjiang River, Zhangjiang River, and Dongxi River basins in Bopingling Mountain, southern Fujian Province, and P. zhangzhouensis and S. hainanensis are, for the first time, confirmed as the first intermediate hosts of P. westermani.

Risk factors and clinical features for pulmonary paragonimiasis-associated pneumothorax.

BACKGROUND: Pulmonary paragonimiasis, a food-borne zoonotic helminthiasis, is a parasitic disease of the lung caused by infection with trematodes species of the genus Paragonimus. Although pneumothorax has been reported as occuring with paragonimiasis, to date no study has been performed concerning the clinical features and predictive risk factors for this condition. METHODS: This retrospective study, which aims to fill this gap, was conducted at Jeonbuk National University Hospital. All patients (aged ≥19 years) were diagnosed with paragonimiasis between May 2011 and December 2021. Medical records were reviewed and information concerning age, sex, vital signs, underlying diseases, clinical signs and symptoms, laboratory findings, radiologic findings, treatment, and clinical outcomes was collected. An odds ratio (OR) for the risk factors associated with pneumothorax was calculated using the binary logistic regression model. RESULTS: Among 179 consecutive patients diagnosed with pulmonary paragonimiasis, the postive rate of pneumothorax was 10.6% (19/179). Pneumothorax occurred mostly in the right lung (78.9%, 15/19), and intrapulmonary parenchymal lesions showed an ipsilateral relationship with pneumothorax (94.7%, 18/19). Fifteen patients (78.9%, 15/19) of pneumothorax associated with pulmonary paragonimiasis are accompanied by pleural effusion. Most of patients with pneumothorax (89.5%, 17/19) underwent chest tube insertion as a first treatment. Three patients (15.8%) showed relapses but in no case was a death recorded. Asthma (odds ratio [OR] 8.10, 95% confidence interval [CI] 1.43-45.91), chest pain (OR 8.15, 95% CI 2.70-24.58), and intrapulmonary lesions (OR 8.94, 95% CI 1.12-71.36) were independent risk factors for pulmonary paragonimiasis-associated pneumothorax. CONCLUSIONS: Our findings suggest that clinicians should keep in mind the possibility of pneumothorax when approached by patients with pulmonary paragonimiasis complaining of chest pain, accompanied by intrapulmonary lesions or with asthma as an underlying disease.

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.

Éclosion locale de pneumothorax spontané secondaire à la paragonimose chez des chiens du sud-ouest de l'Ontario. Trois chiens ont reçu un diagnostic de pneumothorax spontané et ont été référés au Ontario Veterinary College Health Sciences Centre pour prise en charge. Les 3 chiens ont été diagnostiqués avec un pneumothorax spontané secondaire dû à la paragonimose. Le diagnostic a été posé par la visualisation des trématodes adultes lors de l'exploration chirurgicale avec confirmation histopathologique chez 1 chien, et la détection des oeufs de trématodes par sédimentation fécale chez les 2 autres chiens. Deux des chiens ont développé des lésions supplémentaires inhabituelles, notamment un hémoabdomen, un abcès musculaire et des adhérences abdominales. Ces lésions étaient soupçonnées d'être secondaires à une migration larvaire aberrante de la douve. Les 3 chiens vivaient dans une zone géographique relativement restreinte de l'Ontario et ont été hospitalisés entre décembre 2021 et mars 2022. Chaque chien a survécu jusqu'à sa sortie avec une prise en charge chirurgicale ou médicale du pneumothorax et un traitement avec un traitement prolongé au fenbendazole.Message clinique clé :La paragonimose doit être considérée comme un diagnostic différentiel du pneumothorax spontané canin dans les zones où Paragonimus kellicotti est, ou peut être, endémique, ou chez les chiens qui ont voyagé dans des zones endémiques ­ en particulier si le patient a des antécédents de toux ou une exposition potentielle aux écrevisses d'eau douce. Le traitement vermifuge de routine n'empêche pas l'infection et les méthodes de flottaison fécale standard peuvent ne pas détecter les oeufs. Par conséquent, les tests de diagnostic doivent inclure un test de sédimentation fécale et des radiographies thoraciques pour dépister P. kellicotti.(Traduit par Dr Serge Messier).

Pulmonary Paragonimiasis in Native Community, Esmeraldas Province, Ecuador, 2022.

Paragonimiasis is a food-borne infection caused by several species of the Paragonimus fluke. Clinical manifestations can mimic tuberculosis and contribute to diagnostic delay. We report a cluster of paragonimiasis in a community in Ecuador, where active surveillance was set up after detection of the first 2 cases.

A clinical review of human disease due to Paragonimus kellicotti in North America.

Human autochthonous infections with the trematode Paragonimus kellicotti are increasingly being reported in North America, but the true prevalence and geographic distribution are unknown. Ingestion of raw crayfish is reported in most human cases, typically in the context of alcohol intoxication. Risk of infection varies depending on what part of the crayfish is ingested as metacercariae of P. kellicotti (>50% mature to adults) localize to the heart and pericardium of the crayfish. Reported human cases have manifested primarily in otherwise healthy young adults presenting with severe eosinophilic pneumonia, pleuritis, systemic symptoms, dermatologic lesions and cerebral involvement. However, it is likely that many infections go unreported due to lack of awareness, mild illness or the absence of rapid commercially available diagnostic tests. Promising advances have been made related to novel diagnostic targets. Conservation of these antigen targets among at least four Paragonimus species could make these antigens viable for diagnostic testing of P. kellicotti specifically as well as other Paragonimus species, but additional studies and funding investments are required. Public and physician awareness may have improved due to targeted education campaigns, but ongoing activities to raise awareness are needed, particularly in areas where cases have not been frequently reported to date.

Lung flukes of the genus Paragonimus: ancient and re-emerging pathogens.

The title of this article refers to Table 1 in Zhou (2022, Infectious diseases of poverty: progress achieved during the decade gone and perspectives for the future. Infectious Diseases of Poverty 11, 1), in which it is indicated that Paragonimus species, like many other foodborne trematodes, are ancient pathogens that are also re-emerging to cause disease in modern times. This article provides a general overview of Paragonimus species and the disease they cause. This is followed by comments on several specific topics of current interest: taxonomy and distribution of members of the genus; details of the life cycle; global and regional prevalence of paragonimiasis; genomics of lung flukes and possible effects of global environmental change. Unresolved questions relating to these topics are discussed and gaps in knowledge identified.

Sporadic endemicity of zoonotic Paragonimus in raccoon dogs and Japanese badgers from Miyazaki Prefecture, Japan.

Paragonimiasis is a zoonotic trematode infection caused by Paragonimus spp. To determine the recent status of Paragonimus infections in wild animals, this study investigated Paragonimus spp. in 39 raccoon dogs and 54 Japanese badgers from March 2019 to January 2021 in Miyazaki Prefecture, and examined metacercariae in freshwater crabs. Triploid P. westermani was found in one raccoon dog (2.6%), and metacercariae were recovered from Eriocheir japonica captured near the infected animal collected. One Japanese badger (1.9%) harbored P. skrjabini miyazakii; this prevalence was lower than the approximately 30% that was reported in the 1970s. Results indicated that zoonotic Paragonimus was sporadically prevalent in wild animals. Further investigation in various animals is awaited to elucidate current wildlife reservoirs for those Paragonimus.

Pulmonary, liver and cerebral paragonimiasis: An unusual clinical case in Colombia.

BACKGROUND: Mainly affecting poorer populations in remote (sub)tropical areas, paragonimiasis is considered one of the world's most neglected tropical diseases by the World Health Organization. It is usually acquired by consuming undercooked freshwater crustaceans and primarily affects the lungs, but may ectopically migrate to other organs to produce a multisystemic clinical presentation. This study details what appears to be the first documented case in South America and particularly in Colombia of cerebral paragonimiasis and infection by the crab Moreirocarcinus emarginatus. CASE PRESENTATION: After consuming this crab, a 32-year-old Colombian male developed dyspnea and headache. A chest X-ray revealed tension pneumothorax (TPT) and a thoracoscopic lung biopsy bronchiolitis, eosinophilia, and granulomatous reaction due to Paragonimus parasites. RESULTS: Brain tomography and MRI also showed a configuration typical of Paragonimus parasites, namely a predominantly cystic area near the left cuneus with diffusion restriction, a hemosiderin halo, and linear enhancement characteristic of the tunnel sign, indicating an adult worm moving in the brain. CONCLUSIONS: Cerebral paragonimiasis can occur in the Colombian population and Moreirocarcinus emarginatus can be its cause. In rural areas, education about raw crab consumption would be beneficial, and physicians addressing lung-related complaints should bear paragonimiasis in mind and ask about raw crab consumption.

Morphological and Molecular Characterization of Paragonimus skrjabini Complex from Yunnan, China: A Brief Report.

PURPOSE: To perform environmental sampling and molecular identification of Paragonimus in endemic regions, which may help in minimizing transmission among humans. METHODS: Mountain crabs from the genus Potamiscus were collected and the encysted metacercariae were extracted and subjected to morphological identification, followed by animal inoculation in Sprague-Dawley (SD) rats. After 112 days of infection, animals were killed and adult worms were extracted from lungs and muscles. The morphology of adult worms was characterized by microscopy and molecular identification was done by polymerase chain reaction, followed by sequencing of cox1 and ITS2 genes. Phylogenetic analysis was done by maximum parsimony method. RESULTS: A total of 447 crabs were captured from the streams of Tongchang Town, Jinping County, Yunnan Province, China. The infection rate was found to be 41% (186 out of 447 crabs). The metacercariae of Paragonimus skrjabini was identified by the characteristics round or spherical encysted form measuring 410 to 460 × 400 to 460 µm. After animal infection in SD rats, adults were presumptively confirmed to be P. skrjabini, which was also confirmed by gene amplification and sequence analysis of cox1 and ITS2 regions. Paragonimus skrjabini clustered with previously reported P. skrjabini from Yunnan and Vietnam. The confidence values of their branches were > 95%. Phylogenetic analysis of the ITS2 region revealed two distinct clusters with distinct geographical grouping. Phylogenetic analysis with the combined data sets reiterated the geographical grouping with P. skrjabini from Yunnan clustering with strains from Vietnam. CONCLUSION: Metacercariae of P. skrjabini was discovered in freshwater crabs in Yunnan province, China, and the strains were phylogenetically related to P. skrjabini from Vietnam.

The effect of landscape and human settlement on the genetic differentiation and presence of Paragonimus species in Mesoamerica.

Foodborne diseases are a neglected research area, and despite the existence of many tools for diagnosis and genetic studies, very little is known about the effect of the landscape on the genetic diversity and presence of parasites. One of these foodborne disease is paragonimiasis, caused by trematodes of the genus Paragonimus, which is responsible for a high number of infections in humans and wild animals. The main Paragonimus sp reported in Mesoamerica is Paragonimus mexicanus, yet there are doubts about its correct identification as a unique species throughout the region. This, together with a lack of detailed knowledge about their ecology, evolution and differentiation, may complicate the implementation of control strategies across the Mesoamerican region. We had the goal of delimiting the species of P. mexicanus found throughout Mesoamerica and determining the effect of landscape and geology on the diversity and presence of the parasite. We found support for the delimitation of five genetic groups. The genetic differentiation among these groups was positively affected by elevation and the isolation of river basins, while the parasite's presence was affected negatively only by the presence of human settlements. These results suggest that areas with lower elevation, connected rivers basins, and an absence of human settlements have low genetic differentiation and high P. mexicanus presence, which may increase the risk of Paragonimus infection. These demonstrate the importance of accurate species delimitation and consideration of the effect of landscape on Paragonimus in the proposal of adequate control strategies. However, other landscape variables cannot be discarded, including temperature, rainfall regime, and spatial scale (local, landscape and regional). These additional variables were not explored here, and should be considered in future studies.

Paragonimus and its hosts in China: An update.

Paragonimiasis is an important foodborne parasitic disease. Over 50 species of Paragonimus have been reported worldwide, and China has the widest distribution and largest number of species. The detection of Paragonimus metacercariae from second intermediate hosts has been reported in 22 provinces and municipalities. The most frequently reported species are P. westermani, P. skrjabini, P. heterotremus and Euparagonimus cenocopiosus. In this review, we collected and reviewed relevant reports on the detection of Paragonimus metacercariae in second intermediate hosts from 1937 to 2020 from all areas of China. We provide an updated and current summary of Paragonimus species and their hosts in China. Data on the geographical range, species distribution, and second intermediate host species of Paragonimus were extracted. ArcGIS10.2 software was used to generate distribution maps of Paragonimus for four time periods: 1937-1990, 1991-2005, 2006-2020 and 1937-2020. We analyzed the geographic and spatiotemporal dynamics of Paragonimus prevalence in natural foci and provided a basis for further research and paragonimiasis prevention strategies in China.

Endemicity of Paragonimus and paragonimiasis in Sub-Saharan Africa: A systematic review and mapping reveals stability of transmission in endemic foci for a multi-host parasite system.

Paragonimiasis is caused by zoonotic trematodes of Paragonimus spp., found in Asia, the Americas and Africa, particularly in tropical regions. These parasites have a complex, multi-host life cycle, with mammalian definitive hosts and larval stages cycling through two intermediate hosts (snails and freshwater decapod crustaceans). In Africa, paragonimiasis is particularly neglected, and remains the only human parasitic disease without a fully characterised life cycle. However paragonimiasis has potentially significant impacts on public health in Africa, and prevalence has likely been underestimated through under-reporting and misdiagnosis as tuberculosis due to a similar clinical presentation. We identified the need to synthesise current knowledge and map endemic foci for African Paragonimus spp. together with Poikilorchis congolensis, a rare, taxonomically distant trematode with a similar distribution and morphology. We present the first systematic review of the literature relating to African paragonimiasis, combined with mapping of all reported occurrences of Paragonimus spp. throughout Africa, from the 1910s to the present. In human surveys, numerous reports of significant recent transmission in Southeast Nigeria were uncovered, with high prevalence and intensity of infection. Overall prevalence was significantly higher for P. uterobilateralis compared to P. africanus across studies. The potential endemicity of P. africanus in Côte d'Ivoire is also reported. In freshwater crab intermediate hosts, differences in prevalence and intensity of either P. uterobilateralis or P. africanus were evident across genera and species, suggesting differences in susceptibility. Mapping showed temporal stability of endemic foci, with the majority of known occurrences of Paragonimus found in the rainforest zone of West and Central Africa, but with several outliers elsewhere on the continent. This suggests substantial under sampling and localised infection where potential host distributions overlap. Our review highlights the urgent need for increased sampling in active disease foci in Africa, particularly using molecular analysis to fully characterise Paragonimus species and their hosts.

A retrospective clinical analysis of pediatric paragonimiasis in a Chinese children's hospital from 2011 to 2019.

Diagnosis of pediatric paragonimiasis is difficult because of its non-specific clinical manifestations. We retrospectively reviewed the records of pediatric paragonimiasis in Children's Hospital of Fudan University from January 2011 to May 2019. The confirmed diagnosis of paragonimiasis was based on positive anti-parasite serological tests from the local Center for Disease Control (CDC). A total of 11 patients (mean age: 7.7 ± 3.1, male-female ratio: 7:4) diagnosed as paragonimiasis were included. 81.8% were from endemic areas such as Sichuan and Yunnan, and 36% had a clear history of raw crab or crayfish consumption. The characteristic clinical features of pediatric paragonimiasis were eosinophilia (100%), pleural effusion (81.8%), hepatomegaly (54.5%), ascites (54.5%), and subcutaneous nodules (45.5%). Misdiagnosed with other diseases including tuberculosis (18.2%), pneumonia (9.1%), intracranial space-occupying lesions (9.1%) and brain abcess (9.1%) led to rehospitalization and prolonged hospitalization. For treatment, a 3-day course of 150 mg/kg praziquantel (PZQ) didn't show ideal treatment effectivity and 63.6% needed more than one course of PZQ, while triclabendazole in a total dose of 10 mg/kg had a better efficacy to stubborn manifestations. This study indicated that pediatric paragonimiasis was often misdiagnosed, and the treatment with a 3-day course of 150 mg/kg PZQ had a high rate of failure.

An outbreak of Paragonimus westermani infection among Cambodian technical intern trainees in Japan, exhibiting various extrapulmonary lesions.

We encountered an outbreak of paragonimiasis among Cambodian technical intern trainees (TITs) at a food-processing factory in Fukuoka, Japan. The patients were 20-28 years old, seven females and two males, who had been in Japan for one to four years. All of them had consumed raw or undercooked Japanese mitten crab they purchased at a local grocery store near their training place. CT images showed multiple lesions not only in the lungs but in the extrapulmonary organs as well, such as subcutaneous tissues, abdominal muscles, and mesentery, in most of the patients. Their medical records indicated that all of them acquired infection in Japan, not in Cambodia. Diagnosis was made serologically and the patients were treated with praziquantel successfully. Foreign workers and TITs are increasing in Japan so rapidly, that food borne-infections, including paragonimiasis, should be considered in people from developing countries who have exotic dietary habits.

[Investigation on freshwater crab populations and Paragonimus infections in the Minjiang River basin along the middle section of Wuyi Mountain].

OBJECTIVE: To investigate the populations of freshwater crabs, the intermediate host of Paragonimus and Paragonimus infections in freshwater crabs in the Minjiang River basin along the middle section of Wuyi Mountain, so as to provide baseline data for parasitic disease control and research and expansion of the parasite resource bank. METHODS: From November 2020 to April 2021, freshwater crabs were sampled from streams and ditches neighboring residential areas in Jianning County and its neighboring Ninghua, Shaowu, Jiangle and Shunchang counties. The crab species was identified based on the morphological features of the terminal segment of the first abdominal appendage of male crabs, and Paragonimus infections were detected in freshwater crabs. The Paragonimus metacercariae were isolated, and the types of metacercariae were identified based on the metacercaria size, cystic wall thickness, and the excretory bladder and intestinal tract morphology. In addition, the prevalence, intensity and index of metacercaria infections were calculated in freshwater crabs. RESULTS: There were seven crab species found in Jianning County and six neighboring water systems along the Minjiang River basin, including Sinopotamon jianglense, S. fukinense, Huananpotamon lichuanense, H. lini, H. shenni, H. planopodum, Bottapotamon engelhardti, and there were metacercariae of three Paragonimus species detected in these crabs, including P. westermani, P. skrjabini and P. sanpingensis, with a prevalence rate of 43.6% (125/287). The infection rates of P. westermani, P. sanpingensis and P. skrjabini were 57.1% (48/84), 26.2% (22/84) and 61.8% (21/34) in S. jianglense, and the infection rates of P. westermani and P. sanpingensis were 52.6% (51/97) and 30.9% (30/97) in S. fukinense, while the rate of P. westermani infection was 6.9% (5/72) in H. lichuanense, which is the first record of P. westermani infections in H. lichuanense. Mixed P. westermani and P. sanpingensis infections were predominantly found in freshwater crabs sampled from Jianning County, where the rate of Paragonimus infections was 70.4% (76/108), with 15.3 metacercariae identified in each crab with Paragonimus infections and 1.9 metacercariae found in each gram of crabs with Paragonimus infections, and the index of metacercariae infections was 20.5. In addition, P. westermani, P. skrjabini and P. sanpingensi metacercariae were found in freshwater crabs sampled from Jianning-neighboring counties, where the rate of Paragonimus infections was 52.3% (56/107), with 9.8 metacercariae identified in each crab with Paragonimus infections and 0.9 metacercariae found in each gram of crabs with Paragonimus infections, and the index of metacercariae infections was 4.6. CONCLUSIONS: There are multiple freshwater crab species and Paragonimus infection is high in freshwater crabs in Jianning County and its neighboring Minjiang River basin, which is a high-risk natural focus for Paragonimus infections.

Spectrum of pleuropulmonary paragonimiasis: An analysis of 685 cases diagnosed over 22 years.

OBJECTIVES: Paragonimiasis is a global foodborne zoonosis. Overlapping clinical and imaging features with other lung pathologies hamper correct diagnosis and require differential diagnosis. METHODS: During 1982-2003, 49,012 samples were referred for immunodiagnosis of helminthiases. We detected paragonimiasis cases by enzyme-linked immunosorbent assay (ELISA). We assessed clinical, radiographical and laboratory characteristics, and diagnostic dilemmas associated with delayed diagnosis. RESULTS: We analyzed 685 pleuropulmonary paragonimiasis cases. ELISA-positive was 665. Eggs were detected in 50. Symptom duration correlated well with the appearance of chest radiographs; 359 pleural, 33 pleuroparenchymal, and 264 parenchymal lesions (P < 0.001). Twenty-nine had normal chest images. Eosinophilia, seen in 304, was common in pleural and pleuroparenchymal patients (P < 0.05). Chest pain and dyspnea were characteristic for pleurisy patients. Sputum (odds ratios [OR]: 6.79; 95% CI: 4.41-10.47), blood-tinged sputum (OR: 5.62; 95% CI: 3.75-8.42), and foul-odor (OR: 2.70; 95% CI: 1.42-5.16) were significant in parenchymal patients. Delayed diagnosis (119) for ≥ 25 weeks was attributed mainly to misdiagnosis as tuberculosis, malignancy, or chronic obstructive pulmonary disease (COPD) (OR: 111.75; 95% CI: 43.25-288.74). CONCLUSIONS: Variable symptoms and radiographs of pleuropulmonary paragonimiasis depended on the stage of infection. Suspicion of tuberculosis, malignancy, or COPD was major cause of delayed diagnosis.

A case of group infections with Paraginimus species in Henan, Central China.

In July of 2012, mass infections with Paragonimus species were detected in the Henan province sickening 11 of 51 people. In May 2011, these individuals had participated in an excursion during which freshwater crabs were caught and served after being toasted. Before the group infections with Paraginimus species was confirmed, 5 of the 11 patients had been misdiagnosed as tuberculosis (TB) and treated with an anti-TB drug regimen for six months. The most common and typical manifestations were eosinophilia (11/11, 100%) and pulmonary manifestations including, among others, stethalgia and cough (7/11 63.6%). Sero-examination revealed that all 11 patients were seropositive for Paragonimus species. Surprisingly, in our case, one patient presented with hemoptysis and eggs in respiratory secretions, and this is the first time P. skrjabini eggs are detected in the sputum of a patient from the Henan province. Paragonimus metacercariae were collected from 6 of 11 (54.5%) crabs caught at the infection site and were identified as Paraginiumus skrjabini by morphological and molecular examinations. Epidemiological and laboratory evidence confirmed that this is a case of group infection with P. skrjabini. As one of the most neglected tropical diseases (NTD), paragonimiasis should be differentiated diagnosed from TB to avoid the delay of treatment. To our knowledge, this is the second report of a case of group infections with Paraginimus species in Henan, Central China. The first case was reported in 1995. As a kind of food-borne parasitic disease, paragonimiasis should be included in the public health education agenda.

DNA detection of Paragonimus westermani: Diagnostic validity of a new assay based on loop-mediated isothermal amplification (LAMP) combined with a lateral flow dipstick.

Paragonimus westermani (P. westermani) is widely spread in Asian countries and is one of the most important causative agents for lung fluke diseases. The prevention and control of Paragonimiaisis mainly depends on the accurate diagnosis and effective treatment. In this study, we developed a loop-mediated isothermal amplification (LAMP) assay targeted to a portion of the Ty3/gypsy-like LTR retrotransposon (Rn1) sequence coupled with a lateral flow dipstick (LFD) for the rapid detection of P. westermani-specific amplicons. The positive LAMP products were biotin-labeled and hybridized with a fluorescein isothiocyanate-labeled probe which could be visually detected by LFD. No cross-reaction were observed with other parasitic pathogens including Trichinella spiralis, Anisakis simplex, Schistosoma japonicum and Gnathostoma spinigerum, but this LAMP assay could not distinguish P. westermani with Paragonimus skrjabini and Paragonimus heterotremus. The detection limit of the LAMP assay for P. westermani was 2.7 fg/µL, while that of PCR method was 27 fg/µL. LAMP method was applied to detect P. westermani genomic DNA in blood samples form experimental infected dogs, and results showed the parasite was detectable as early as week 2. LAMP-LFD assay applicability was successfully tested in dog blood samples collected from five cities (Wenzhou, Hangzhou, Huzhou, Jiaxing and Shaoxing) in Zhejiang province. In summary, the established LAMP-LFD assay targeted to the Rn1 sequence is a rapid and convenient method for specific detection of P. westermani.

Paragonimus and paragonimiasis in Asia: An update.

Paragonimiasis, or lung fluke disease, is a typical food-borne parasitic zoonosis caused by infection with trematodes belonging to the genus Paragonimus. More than 50 species of Paragonimus have been reported throughout the world, of which seven valid species infect humans, an estimated one million people annually worldwide. Among the seven species, P. westermani, P. heterotremus, and P. skrjabini/P. s. miyazakii, distributed in Asia, are the most important species as the cause of paragonimiasis. Humans acquire infection through the ingestion of raw, pickled or undercooked freshwater crustaceans, 2nd intermediate hosts, or consuming raw meat of wild boar or deer, paratenic hosts. Infections often occur clustered in foci where dietary habits allow transmission of the parasites. Paragonimiasis typically causes a subacute to chronic inflammatory disease of the lungs. The symptoms, including chronic cough, chest pain, dyspnea and hemoptysis, mimic those of tuberculosis and lung cancer. Serologic tests are commonly used for the diagnosis of paragonimiasis, and Praziquantel is the treatment of choice. In this review, the current status of Paragonimus and paragonimiasis in Asia is outlined based on the latest information and findings. We also summarize current trends of paragonimiasis in Japan, which is one of the most endemic area of paragonimiasis in the world, for the better understanding and control of paragonimiasis.

Estimation of disability weight for paragonimiasis: a systematic analysis.

BACKGROUND: Paragonimiasis, caused by helminths of the genus Paragonimus spp., is a neglected tropical disease. Human suffering from paragonimiasis is often misunderstood and its quantification by the disability weight of the disability-adjusted life years largely varies in different global burden of disease (GBD) estimates. This paper is to systematically review clinical paragonimiasis cases and requantify the disability weight of human paragonimiasis. METHODS: A systematic analysis was conducted using articles from the following databases: PubMed, Institute for Scientific Information Web of Science, China National Knowledge Infrastructure, the Chinese scientific journal databases Wanfang Data and CQVIP, Africa Journal Online, and the System for Information on Grey Literature in Europe. Search terms were the combination of "paragonim*" with "clinical" or "infection". Only articles fulfilling the following conditions were recruited for this study: the occurrence of clinical signs and symptoms of paragonimiasis in human beings were reported; diagnosis was confirmed; no comorbidities were reported; the reviewed clinical cases or epidemiological findings were not already included in any other articles. The information and frequencies of paragonimiasis outcomes from included articles using predefined data fields were extracted two times by two separate individuals. Outcome disability weights were selected mainly from the GBD 2004 and GBD 2013 datasets. Frequencies and disability weights of paragonimiasis outcomes were modelled into a decision tree using the additive approach and multiplicative approach, respectively. Monte Carlo simulations were run 5000 times for an uncertainty analysis. RESULTS: The disability weight estimates of paragonimiasis were simulated with 5302 clinical cases from 80 general articles. The overall disability weight was estimated at 0.1927 (median 0.1956) with a 95% uncertainty interval (UI) of 0.1632-0.2378 using the additive approach, and 0.1791 (median 0.1816) with a 95% UI of 0.1530-0.2182 using the multiplicative approach. The simulated disability weights of Paragonimus westermani cases were higher than that of P. skrjabini cases. Lung outcomes and headache were the top two contributors to disability weight for both species. CONCLUSIONS: The use of paragonimiasis disability weight needs to be reconsidered with regard to availability of morbidity data and species variation. Calculating the disease burden of paragonimiasis requires further modification and thus has considerable implications for public health prioritization in research, monitoring, and control.