Hepatic pseudotumor associated with Strongyloides infection:A case report

BACKGROUND Strongyloides sterocoralis is a parasitic infection caused by a roundworm that is transmitted through soil contaminated with larvae.It can infrequently cause hepatic abscesses in immunocompromised patients and is rarely reported to form hepatic lesions in immunocompetent hosts.CASE SUMMARY We present a case study of a 45-year-old female who presented with right upper quadrant abdominal pain and constitutional symptoms for several weeks.Crosssectional imaging identified several malignant-appearing liver masses.Further investigation,including serological testing and histopathologic examination,revealed the presence of serum Strongyloides antibodies and hepatic granulomas with extensive necrosis.Following treatment with ivermectin for 2 wk,there was complete resolution of the liver lesions and associated symptoms.CONCLUSION This case highlights the importance of considering parasitic infections,such as Strongyloides,in the differential diagnosis of hepatic masses.Early recognition and appropriate treatment can lead to a favorable outcome and prevent unnecessary invasive procedures.Increased awareness among clinicians is crucial to ensure the timely diagnosis and management of such cases.

A case report of pulmonary coinfection of Strongyloides stercoralis and Pneumocystis jiroveci

A case of pulmonary coinfection by Strongyloides stercoralis and Pneumocystis jiroveci has been detected in an AIDS patient treated in the Respiratory Intensive Care Unit of the Muniz Hospital.At diagnosis,the patient presented cough with mucopurulent expectoration,dyspnea,fever,bilateral pulmonary infiltrates on the chest X-ray,negative bacilloscopy for acid fast bacteria and a CD4^+ T lymphocytes count of 52 cells/μ L.The microbiological diagnosis was achieved by microscopic observation of the respiratory secretions obtained by bronchoalveolar lavage,while the wet mount examination revealed rhabditiform and filariform larvae of the nematode and foamy exudates,pathognomonic of the pulmonary pneumocystosis.It was the unique case of this association among about 3 000 samples performed in our laboratory in the last 10 years and diagnosed by microscopy.Other complementary stains(a rapid modification of Grocott,Kinyoun and Giemsa) were applied to the smears after the diagnosis of mycotic and parasitary infections achieved by fresh microscopy.Both physicians and microbiologists should take into account the possible coexistence of respiratory pathogens in immunocompromised patients,such as those with AIDS.

Adult female of strongyloides stercoralis in respiratory secretions

Objective:To communicate the presence of adult females,rabditoid larvae and eggs of Strongyloides stercoralis(S.stercoralis)in the respiratory secretions obtained by tracheal aspirate from a HIV-negative patient who was suffering from polymyositis,and treated with corticoids and amethopterin and assisted by pneumonia.Methods:The respiratory secretions submitted to the Parasitology Laboratory of the Mu(?)iz Hospital were made more concentrated by centrifugation(1 500 r/min for 15 seconds).Wet mount microscopy was performed with the pellet.Results:It revealed adult females,rabditoid larvae and eggs of S.stercoralis.Further parasitological studies performed after the start of the treatment with ivermectin on fresh fecal samples,gastric lavages and tracheal aspirates showed scanty mobile filariform and rabditoid larvae of the same parasite.Conclusions:The presence of adult female S.stercoralis which has never been observed before in the clinical samples submitted to our Laboratory for investigation can be considered as an indirect marker of the severe immunosupression of the patient.

Epidemiology and immunodiagnostics of Strongyloides stercoralis infections among migrant workers in Malaysia

Objective: To investigate the status of Strongyloides(S.) stercoralis infections among migrant workers in Malaysia for the first time and identify risk factors.Methods: Four diagnostic methods were employed for the detection of S. stercoralis including microscopy, enzyme-linked immunosorbent assay(ELISA) using a commercial kit, ELISA using the rSs1a antigen and polymerase chain reaction(PCR). Low and semi-skilled workers from five working sectors(i.e. manufacturing, food service, agriculture and plantation, construction and domestic service) were tested on a voluntary basis. Results: The overall seroprevalence of S. stercoralis from 483 workers employing the ELISA commercial kit for IgG was 35.8%(n=173;95% CI: 31.5%-40.1%) whereas seroprevalence using the rSs1a-ELISA was 13.0%(n=63;95% CI: 10.0%-16.0%). Cross tabulation between the ELISA commercial kit and rSs1a-ELISA showed that only 6.4%(n=31;95% CI: 4.2%-8.6%) of the samples were positive in both tests. Microscopic examination of all 388 fecal samples were negative;however subsequent testing by a nested PCR against DNA from the same samples successfully amplified DNA from three male subjects(0.8%;3/388). Male workers, India and Myanmar nationality, food service occupation and those living in the hostel were statistically significant with seroprevalence(P<0.005). Conclusion: This is the first report on the epidemiology of S. stercoralis infections among the migrant workers in Malaysia. Our results highlight the importance of using appropriate diagnostic tools for detection. The presence of anti-S. stercoralis antibodies in the study population calls for improvements in personal hygiene and sanitation standards among migrant workers in Malaysia through control strategies including health education campaigns and programs aimed at increasing awareness and healthy behaviors.

Prevalence of Strongyloides stercoralis and other intestinal parasitic infections among mentally retarded residents in central institution of southern Iran

Objective:To determine the prevalence of intestinal parasitic infections among mentally retarded residents of rehabilitation center of Bandar Abbas,Hormozgan province,southern Iran.Methods:A cross-sectional study was carried out in central rehabilitation institute of Hormozgan province in summer 2010.Fecal samples of all 133 residents(72 males,61 females)aged 3-52,were collected in triplicate.Specimens were examined by direct smear,formalin-ether concentration techniques and stained by permanent Trichrome,Ziehl-Neelsen stains.Statistical analysis was conducted by SPSS 13.5.Results:Intestinal parasitic infections were seen in 48.5%(64 out of 133 subjects:53.4%in males and 46.6%in females).Strongyloides stercoralis with17.3%showed the highest incidence followed by Entamoeba coli(9.8%),Blastocystis hominis(7.5%),Giardia lamblia(2.3%),Endolimax nana(2.3%),Hymenolepis nana(0.8%),Oxyuris vermicularis(0.8%),and Chilomasix mesnili(0.8%).Double infections were found to be as:Strongyloides stercoralis+Giardia lamblia(2.3%),Entamoeba coli+Giardia lamblia(1.5%),Entamoeba coli+Blastocystis hominis(1.5%),Oxyuris vermicularis+Entamoeba coli(0.8%),Strongyloides stercoralis+Entamoeba coli(0.8%),respectively.Conclusions:Our findings reveal that strongyloidiasis is a common disease among mentally retarded population in southern Iran.

Strongyloides stercoralis in an immunocompetent adult:An unexpected cause of weight lost

Strongyloides stercoralis infects at least 100 million humans worldwide each year, but its prevalence is underestimated. It is endemic in hot and humid climates as well as resource poor countries with inadequate sanitary conditions. The rise of international travel and immigration has a positive impact in strongyloidiasis. Due to its unique auto infection life-cycle, Strongyloides may lead to chronic infections remaining undetected for decades. Strongyloidiasis is most often asymptomatic but it has a wide range of clinical presentations. The two most severe forms of strongyloidiasis are hyperinfection and disseminated syndromes. These occur most often in patients with impaired cell mediated immunity. A 42-year-old immunocompetent man presented with chronic watery diarrhea, malaise, upper abdominal pain, anorexia and weight lost. Strongyloides stercoralis was identified in stool samples and duodenal biopsy. The patient was successfully treated with albendazole. The authors report a case of strongyloidiasis hyperinfection in an immunocompetent host 20 years away from an endemic area and make a literature review.

猪兰氏类圆线虫(Strongyloides ransomi)的研究 Ⅱ.猪兰氏类圆线虫的自由生活世代形态的描述与生态的观察

一、本实验通过培养对猪兰氏类元线虫自由生活世代各期幼虫及成虫的形态作了观察描述。对该虫的生态进行观察,发现该虫在适宜气温及湿度下繁殖传代很快,在室温25～31℃时,培养后7～12小时可获第一期杆状幼虫,20～48小时可获雌、雄成虫,24～36小时可见到第三期丝状幼虫。这期丝状幼虫在湿润条件下,能生存8～16天,在低温4～7℃时,四天后仍有生活能力。二、用乎皿培养法培养猪兰氏类元线虫,在皿内感染性丝状幼虫与毛霉菌属霉菌共生良好,起相互作用。三、感染性丝状幼虫尾部末端分叉与人体粪类园线虫丝状幼虫尾部末端分叉一样,两者虫体大小、结构无明显差异,是否能人畜共患,值得提出研究。

猪兰氏类圆线虫(Strongyloides ransomi)的研究 Ⅰ.猪兰氏类圆线虫感染家兔的实验及其形态的描述

一、本文实验系用患类元线虫病小猪的感染性幼虫接种家兔,不论口服或皮肤感染,均获得成虫,接种后10一16天分别在粪便中发现大量含有幼虫的虫卵。二、本实验人工感染家兔所获虫体全系雌虫,虫体细小,头端小,体表具横纹,口部有四个不明显唇瓣,其上各有一个稍隆起的乳突,口囊短,呈柱样无齿,食道细长,后端无食道球,雌虫体长2.95—5.22毫米,体宽0.061—0.096毫米,食道长0.783—1.044毫米,食道宽0.045—0.061毫米,阴门——尾端1.175—1.740毫米,肛门一尾端0.070—0.104毫米,阴门位于虫体后1/3腹侧面,卵为椭元形,壳薄,大小为0.045—0.063×0.026—0.038毫米。三、解剖家兔四只,从小肠粘膜内获得雌虫21—246条,其成虫分布以小肠上1/3段最多,达263条,其次中1/3段,142条,最少下1/3段,20条。除小肠外,其他肺、肝未见虫体。四、兔肠病损轻重,与感染程度及感染时间长短有关,其虫体较多寄居的肠段粘膜充血明显,但未见溃疡,患病后生长迟缓,消瘦,间歇性屙烂便。

A study implementing real-time PCR to identify Strongyloides species of third-stage larvae in human stool samples from Southern Vietnam

Background:Strongyloidiasis,a neglected disease caused by intestinal nematodes of the genus,is endemic to tropical and subtropical areas such as Vietnam.Morphological methods only identify the genus,while DNA-molecular techniques are susceptible in Strongyloides spp.detection.The study aims to determine the prevalence of dominant Strongyloides species among the population in Duc Hoa district,Long An,Vietnam.Methods:A cross-sectional study used 1190 stool specimens collected from July 2017 to November 2018.All samples were transported within 2 h,stored at 2-8℃,and processed within 48 h for microscopy smear and culture at the Laboratory of Medical Parasitology,Pham Ngoc Thach University of Medicine(PNT).Then all positive samples with the above 2 methods were verified by real-time PCR technique.Real-time PCR amplification was conducted at the Laboratory of Molecular Biology,PNT.Results:Direct microscopy and modified Harada-Mori culture detected Strongyloides spp.larvae in 79/1190 sam-ples(6.6%).About 94.2%of the DNA samples were Strongyloides stercoralis,2.9%were co-infections with Strongy-loides ratti and S.stercoralis,and 2.9%were patients with S.ratti.The identity of 12/14 sequences was confirmed as S.stercoralis with a high level of similarity(91.3%-100%)and over 98%for S.ratti.Conclusion:DNA-molecular techniques and sequence analysis are highly suitable for identifying Strongyloides species isolated from stool samples.It is remarkable evidence of the presence of zoonosis S.ratti disease in human,not just the known S.stercoralis.It is likely to result in a certain proportion of people being infected by this animal-borne infectious pathogen.

Prevalence of Strongyloides in Southeast Asia:a systematic review and meta-analysis with implications for public health and sustainable control strategies

Background Strongyloidiasis,caused by the nematodes Strongyloides stercoralis and Strongyloides fuelleborni,is estimated to afect over 600 million individuals worldwide.The disease is endemic in Southeast Asia,where a warmhumid climate and socio-economic conditions maintain the parasite’s life cycle and transmission.However,the current diagnostic methods may not be sufciently sensitive,suggesting that the true prevalence of strongyloidiasis could be seriously underestimated in this.This study aims to determine the prevalence of strongyloidiasis in Southeast Asia through a systematic review and meta-analysis and to discuss the implications of the estimated prevalence on diagnostic approaches and control strategies.Methods Following PRISMA guidelines,we conducted a systematic literature search in PubMed and Google Scholar databases to identify studies reporting Strongyloides prevalence data in the 11 Southeast Asian countries up to December 2022.A random efects model was employed to estimate the pooled prevalence of S.stercoralis at both regional and country levels.Results Out of 3722 articles identifed,224 met our inclusion criteria.For S.stercoralis specifcally,we found 187 articles,of which 52.4%were from Thailand.All Southeast Asian countries,except Brunei,had at least one study on Strongyloides prevalence.The estimated pooled prevalence of S.stercoralis regionally was 12.7%(95%CI 10.70-14.80%),ranging from 0.4 to 24.9%at the country level.Cambodia had the highest pooled prevalence(24.9%,95%CI 15.65-35.38%),followed by Lao PDR(16.5%,95%CI 9.50-24.95%).Moreover,we obtained a pooled prevalence of 10%(95%CI 7.06-13.52%)in a group comprising immigrants,workers,and veterans from Southeast Asian countries.S.stercoralis infects various host types,including nonhuman primates,domestic dogs and cats,rodents,and transport carriers such as cockroaches and vegetables.Conclusions A high prevalence of strongyloidiasis in Southeast Asia was revealed,highlighting the importance of the region’s ongoing research,surveillance,and control eforts.Factors contributing to the strongyloidiasis transmission include the role of animal hosts,the impact of global connectivity,and the signifcance of the co-endemicity of other Strongyloides species.Based on these fndings,a multi-pronged One-Health approach is essential for sustainable intervention and control.

Strongyloides stercoralis prevalence and diagnostics in Vientiane, Lao People’s Democratic Republic

Background:Despite the high prevalence of strongyloidiasis in the Laotian population,Laotian hospitals still lack diagnostic capacity to appropriately diagnose Strongyloides stercoralis infections.This cross-sectional hospital-based study was conducted to assess the prevalence of Strongyloides stercoralis infection among hospitalized patients treated at Mahosot Hospital,the primary reference hospital of Lao People’s Democratic Republic(Lao PDR),and to validate feasible methods for diagnosing S.stercoralis infection at hospital’s laboratory.Methods:Between September and December 2018,stool samples of 104 inpatients were investigated for S.stercoralis infection by wet smear,Baermann technique,Koga Agar plate culture(KAPC),and real-time detection polymerase chain reaction(RTD-PCR)at the Infectious Diseases Ward of the Mahosot Hospital in Vientiane.The sensitivity,the specificity,the negative predictive value(NPV)of each diagnostic test,as well as their combination(s)was calculated using a composite reference standard(CRS).The correlation of the different test methods was assessed by chi-square or Fisher’s exact test.Cohen’s kappa coefficient was used to assess the diagnostic agreement of the different test methods.Results:The overall prevalence of S.stercoralis infections among the study population was 33.4%.The cumulative infection prevalence statistically significantly increased from the lowest age group of 40 years and below(22.4%),to the medium(40.0%)and to the oldest age group of 61 year and above(72.7%)(P=0.003).The cumulative infection prevalence of CRS was considerably higher in male(40.4%)compared to female patients(28.1%),but not statistically different(P=0.184).The diagnostic sensitivity of Baermann technique,KAPC,RTD-PCR,and the combination of Baermann technique and KAPC were 60.0,60.0,74.3,and 77.1%,respectively.Only 13 patients(37.1%)of the total 35 S.stercoralis patients diagnosed with any technique had a simultaneously positive diagnostic test with Baermann,KAPC and RTD-PCR.Conclusions:We identified Baermann technique and KAPC to be currently the most feasible and implementable standard methods for diagnosing S.stercoralis at a hospital setting such as Mahosot Hospital and provincial and district hospitals in Lao PDR and other low-and middle income countries in Southeast Asia.Trial registration:This study was approved by the National Ethics Committee for Health Research in Lao PDR(reference no.083/NECHR)and by the Ethics Committee Northwest and Central Switzerland(reference no.2018–00594).

Strongyloidiasis:A case with acute pancreatitis and a literature review

Strongyloides stercoralis,a soil transmitted helminth infection,affects millions with varying prevalence worldwide.A large number of affected hosts are asymptomatic.Symptoms pertaining to pulmonary and gastrointestinal involvement may be present.Manifestations of involvement beyond lung and intestine can be seen with dissemination of infection and lethal hyperinfection.Immunosuppression secondary to use of steroids or other immunosuppressants and coexistence of human T-lymphotropic virus type-1 are the known risk factors for dissemination and hyperinfection.Diagnostic modalities comprise stool examination,serology and molecular testing.Stool tests are inexpensive but are limited by low sensitivity,whereas serologic and molecular tests are more precise but at the expense of higher cost.Treatment with Ivermectin or Albendazole as an alternative is safe and efficacious.We present a rare case of acute pancreatitis secondary to Strongyloides.High index of suspicion in patients specifically from endemic countries of origin and lack of other common etiologies of acute pancreatitis may help in early diagnosis and prompt treatment of this potentially fatal infection.

Disseminated strongyloidiasis in an immunocompromised host:A case report

Infections caused by Strongyloides stercoralis(S.stercoralis) in human are generally asymptomatic,however in immunocompromised individual,hyperinfection may develop with dissemination of larvae to extra-intestinal organs.The diagnosis could be easily missed due to asymptomatic presentation and insufficient exposure towards the infection itself,which may lead to low index of suspicion as a consequence.In this report,a case of a Malaysian male with underlying diabetes mellitus,hypertension,cerebrovascular accident,bullous pemphigus and syndrome of inappropriate antidiuretic hormone secretion who initially complained of generalized body weakness and poor appetite without any history suggestive of sepsis is presented.However,he developed septicemic shock later,and S.stercoralis larvae was incidentally found in the tracheal aspirate that was sent to look for acid fast bacilli.Regardless of aggressive resuscitation,the patient succumbed due to pulmonary hemorrhage and acute respiratory distress syndrome.It was revealed that the current case has alarmed us via incidental finding of S.stercoralis larvae in the tracheal aspirate,indicating that the importance of the disease should be emphasized in certain parts of the world and population respectively.

Unusual form of strongyloidiasis with gastric involvements: A case report

Rationale: Strongyloides stercoralis (S. stercoralis) is an intestinal nematode with a complicated life cycle that can involve the gastrointestinal system. Infected patients are generally asymptomatic;but if symptomatic, the symptoms will include skin rash, respiratory and gastrointestinal symptoms like abdominal pain, diarrhea, nausea and vomiting. Patient concerns: A 77-year old man presented with edema of the lower extremities and insignificant tenderness in the epigastric region. Diagnosis: The histopathology of gastric tissue showed severe inflammation and multiple ulcers in the cardia, antrum and proximal duodenum. A large number of rhabditiform larvae of S. stercoralis along with tissue hyperemia and infiltration of lymphoplasma cells, eosinophils, and neutrophils were found. Intervention: Treatment with albendazole. Outcome: Despite the albendazole treatment, the patient's condition deteriorated and eventually died because of a sepsis-like syndrome. Lesson: Physicians should remain alert to the urgency due to threadworm, especially among the elderly people and immunosuppressed cases;and should ensure accurate diagnosis, suitable treatment and careful follow-up of these cases.

Urogenital schistosomiasis and soiltransmitted helminthiasis(STH)in Cameroon:An epidemiological update at Barombi Mbo and Barombi Kotto crater lakes assessing prospects for intensified control interventions

Background:The crater lakes of Barombi Mbo and Barombi Kotto are well-known transmission foci of schistosomiasis and soil-transmitted helminthiasis having had several important control initiatives previously.To collect contemporary epidemiological information,a cross-sectional survey was undertaken inclusive of:signs and symptoms of disease,individual treatment histories,local water,sanitation and hygiene(WASH)-related factors and malacological surveillance,with molecular characterisation of specimens.Methods:At each lake,a community cross-sectional survey was undertaken using a combination of stool and urine parasitological sampling,and interview with pro-forma questionnaires.A total of 338 children and adults participated.Material from snail and parasite species were characterised by DNA methods.Results:Egg-patent prevalence of urogenital schistosomiasis was 8.7%at Barombi Mbo(all light-intensity infections)and 40.1%at Barombi Kotto(21.2%heavy-intensity infections).Intestinal schistosomiasis was absent.At Barombi Kotto,significantly more women reported signs and symptoms associated with female genital schistosomiasis.While there had been extensive recent improvement in WASH-related infrastructure at Barombi Mbo,water contact risk scores were higher among schistosomiasis-infected participants(P<0.001)and at Barombi Kotto in general(P<0.001).Across both lakes,mean prevalence of STH was very low(6.3%)evidencing an impressive decrease of 79.0%over the last decade;neither Strongyloides stercoralis nor Ascaris lumbricoides were found.A total of 29 freshwater sampling sites were inspected for snails,13 in Barombi Mbo and 16 in Barombi Kotto;water chemistry differed significantly(P<0.0001)between lakes for both mean pH(7.9 v.9.6)and mean conductivity(64.3μS v.202.1μS)respectively.Only two Bulinus camerunensis found on the central island of Barombi Kotto were observed to shed schistosome cercariae,but schistosome DNA was later detected in Bulinus sampled from both lakes as well as in Indoplanorbis exustus,an invasive species from Asia.Conclusions:STH is currently at very low levels while urogenital schistosomiasis is of greatest concern at Barombi Kotto.This assessment highlights a unique opportunity for further study of the epidemiological dynamics at these crater lakes,to evaluate future intensified interventions both in terms of gaining and sustaining control at Barombi Kotto or in moving towards local interruption of transmission of both diseases at Barombi Mbo.

Strongyloidiasis in Ethiopia:systematic review on risk factors,diagnosis,prevalence and clinical outcomes

Background:Strongyloidiasis is a gastrointestinal infection caused by the parasitic nematode Strongyloides stercorolis.It is estimated to infea up to 370 million people globally and is predominately found in tropical and subtropical areas of socioeconomic disadvantage.Main body:This systematic literature review identified studies published in the last ten years on the risk factors,diagnosis,prevalence and/or clinical outcomes of strongyloidiasis in Ethiopia.The prevalence of 5.stercoralis ranged from 0.2 to 11.1%in adults,0.3%to 20.7%in children,1.5%to 17.3%in HIV positive adults and 5%in HIV positive children.The identified studies primarily used microscopy based techniques that potentially underestimated the prevalence four fold compared with serology and PCR.Strongyloidiasis in children presents a particularly significant issue in Ethiopia as children often presented with anemia,which is associated with impaired mental and cognitive development.The most significant risk factor for strongyloidiasis was HIV status and although other risk factors were identified for helminth infections,none were statistically significant for 5.stercoralis specifically.Several studies detected 5.stercoralis in dogs and non-biting cyclorrhaphan flies.However,future research is needed to explore the role of these reservoirs in disease transmission.Conclusions:This review demonstrated that strongyloidiasis is an overlooked and neglected disease in Ethiopia.There is a need for a systematic approach using a combination of molecular and serology based diagnostic methods to ascertain the true incidence and burden of strongyloidiasis in Ethiopia.Further research is also needed to break the cycle of transmission by identifying environmental reservoirs,risk factors and exploring the potential for zoonotic transfer.

Prevalence of chronic infections and susceptibility to measles and varicellazoster virus in Latin American immigrants

Background:Large numbers of Latin American immigrants recently arrived in Western Europe.Curative and preventive programmes need to take account of their risk of suffering and transmitting imported chronic infections and of their susceptibility to cosmopolitan infections.We aimed to assess the prevalence and co-occurrence of imported chronic infections among Latin American immigrants,and their susceptibility to highly prevalent cosmopolitan infections.Methods:Adult participants were recruited in the community and in a primary health centre in Geneva in 2008.Serological tests were performed on stored sera for HIV,HBV,syphilis,Strongyloides stercoralis,Trypanosoma cruzi,varicella and measles.We considered only chronic active infections in the analysis.Results and discussion:The 1012 participants,aged 37.2(SD 11.3)years,were mostly female(82.5%)and Bolivians(48%).Overall,209(20.7%)had at least one and 27(2.7%)two or more chronic infections.T.cruzi(12.8%)and S.stercoralis(8.4%)were the most prevalent chronic active infections compared to syphilis(0.4%),HBV(0.4%)and HIV(1.4%).Concomitant infections affected 28.2 and 18.5%of T.cruzi and S.stercoralis infected cases.Bolivian origin(aOR:13.6;95%CI:3.2–57.9)was associated with risk of multiple infections.Susceptibilities for VZV and measles were 0.7 and 1.4%,respectively.Latin American immigrants are at risk of complications and possible reactivation of chronic parasitic infections but have overall low risks of chronic viral and syphilitic active infections.Conclusions:Systematic screening for chronic active parasitic infections is therefore necessary especially among Bolivians.The high protection rate against measles and VZV doesn’t require specific preventive interventions.

Control programs for strongyloidiasis in areas of high endemicity: an economic analysis of different approaches

Background:Implementation of control programmes for Strongyloides stercoralis infection is among the targets of the World Health Organization Roadmap to 2030.Aim ofthis work was to evaluate the possible impact in terms of economic resources and health status of two different strategies of preventive chemotherapy(PC)compared to the current situation(strategy A,no PC):administration of ivermectin to school-age children(SAC)and adults(strategy B)versus ivermectin to SAC only(strategy C).Methods:The study was conducted at the IRCCS Sacro Cuore Don Calabria hospital,Negrar di Valpolicella,Verona,Italy,at the University of Florence,Italy,and at the WHO,Geneva,Switzerland,from May 2020 to April 2021.Data for the model were extracted from literature.A mathematical model was developed in Microsoft Excel to assess the impact of strategies B and C in a standard population of 1 million subjects living in a strongyloidiasis endemic area.In a case base seenario,15%prevalence of strongyloidiasis was considered;the 3 strategies were then evaluated at different thresholds of prevalenee,ranging from 5 to 20%.The results were reported as number of infected subjects,deaths,costs,and Incremental-Effectiveness Ratio(ICER).A 1-year and a 10-year horizons were considered.Results:In the case base seenario,cases of infections would reduce dramatically in the first year of implementation of PC with both strategy B and C:from 172500 cases to 77040 following strategy B and 146700 following strategy C.The additional cost per recovered person was United States Dollar(USD)2.83 and USD 1.13 in strategy B and C,respectively,compared to no treatment in the first year.For both strategies,there was a downtrend in costs per recovered person with increasing prevalenee.The number of adverted deaths was larger for strategy B than C,but cost to advert one death was lower for strategy C than B.Conclusions:This analysis permits to estimate the impact of two PC strategies for the control of strongyloidiasis in terms of costs and adverted infections/deaths.This could represent a basis on which each endemic country can evaluate which strategy can be implemented,based on available funds and national health priorities.

肝胆管类圆虫病表现为食管胃十二指肠镜和超声内镜下的壶腹病变

Strongyloidiasis is an intestinal infection caused by the parasitic nematodes of the Strongyloides species,most commonly Strongyloides stercoralis.We report a case of a 66-year-old immigrant male from Haiti who presented with complaints of diarrhea and an unintentional 80-lb weight loss over the past 5 years.Stool examination was positive for strongyloidiasis.Following albendazole therapy,esophagogastroduodenoscopy(EGD)showed a unique ampullary lesion.Histopathology of the ampullary lesion showed reactive epithelium with Strongyloides larva.In addition,endoscopic ultrasound(EUS)detected a large pancreatic cyst.Both these findings were absent on EGD 5 years previously,prior to the onset of his symptoms.This paper documents a rare case of an ampullary lesion and pancreatic cyst secondary to hepatobiliary strongyloidiasis in a non-Human Immunodeficiency Virus(HIV)patient.We review the epidemiology,life cycle,clinical presentation and treatment of strongyloidiasis.