[Nasal myiasis due to lucilia sp. in intubated patient: about one case in Morocco]

INTRODUCTION

Myiasis is the infestation of living bodies of animals and humans with fly larvae or maggots. These accidental or obligatory parasites grow in three stages in the host while feeding on his tissues. Myiasis in a hospital area is a rare situation when flies accidentally lay their eggs on patients, mostly in open wounds or cavities. Case presentation. We report a case of a 72-year-old patient admitted to a general surgery department for peritonitis, then to an intensive care unit (ICU) for septic shock where he was intubated. Some maggots were seen moving in his nasal cavity a few days after his admission and were sent to our laboratory for examination. The larvae were identified as the third larval stage of Lucilia sp. They were removed entirely after intense nasal washing. A checking examination of his nasal cavities revealed no evidence of further infestation. After nasal washing, no other larvae were seen but unfortunately, the patient died of septic shock a few days later.

DISCUSSION

Few cases of nasal myiasis in hospitalized patients were reported. ICU myiasis, extremely rare, is caused by the patient's inability to fend off the flies because of their conscious state, presence of blood or odors caused by infections, and the warm humid environment.

CONCLUSION

Myiasis in intensive care unit is a delicate situation that might be underreported. Preventing this infection is directly related to the control of the flies.

Accidental Nasal Myiasis Caused by Megaselia rufipes (Diptera: Phoridae) in a Child

A case of a nasal myiasis in a 3-yr-old Italian girl who was referred to Bambino Gesù Hospital in Rome, Italy, is reported. Larvae discharged with the nasal mucus were microscopically identified as Megaselia spp.; DNA barcoding analysis showed that they belonged to the 'scuttle fly' species Megaselia rufipes (Meigen). Based on the patient's history, she became infected when she played outside. This is the first report of myiasis in humans due to M. rufipes (Diptera: Phoridae).

Dynamics of infestation by Rhinoestrus usbekistanicus in donkeys (Equus asinus) in Tunisia

Examination of a total of 125 slaughtered donkeys in Tunisian slaughterhouses revealed the presence of 1,508 larvae of Rhinoestrus usbekistanicus in their nasal cavities, with an overall infestation prevalence of 52.8%. The highest overall intensity (number of larvae per infested donkey) and abundance (number of larvae per donkey examined) of infestation were reported in winter (35.6 and 12.1, respectively). Larvae 1 (L1) were the most frequent stage and reached a peak prevalence of 100% during November. The number of larvae 2 (L2) and 3 (L3) was low and the maximum was recorded during March and April. Post-mortem observations showed that infestation intensity increases with age. The ethmoid bone was the most frequently infected portion of the nasal cavity (83.75%). This is the first study on nasal bots in donkeys in Tunisia.

Genetic diversity of an avian nasal schistosome causing cercarial dermatitis in the Black Sea-Mediterranean migratory route

This study is part of an effort to document the diversity of avian schistosomes in ducks and snails in Northern Iran, a major flyway (Black Sea/Mediterranean) for migratory birds and where cercarial dermatitis (CD) is prevalent in rice growing areas. CD is an allergic skin reaction from schistosome trematodes that emerge from aquatic snails. Most CD cases are reported from recreational swimmers or aquaculture farmers. Much of the work on the epidemiology of CD has focused in recreational waters in the Americas and Europe, with fewer studies in aquaculture, particularly in Iran. The artificial environment at aquaculture sites support dense populations of snails that are hosts to schistosomes, as well as domestic ducks. Thus, are domestic ducks reservoir hosts of species of Trichobilharzia, one of the main etiological agents of CD in Northern Iran? This study focused on a survey of domestic ducks for the presence of the nasal schistosome, T. regenti, that has been reported widely in Europe. Trichobilharzia regenti were found in domestic ducks in the Guilan Province of Iran based on morphological and molecular analyses. The presence of this species in Northern Iran indicates that the domestic duck can serve as a reservoir host for this species and that one of the local snail species is likely the intermediate host. The continued study and surveillance of this species is important because it is a neuropathic schistosome that can use a diversity of bird definitive hosts and Radix snails that are widespread across Eurasia.

Taenia Solium Sneezed out from Nose by an Asymptomatic Child

Taenia solium is an intestinal parasite and may be excreted in feces in infected patients but our case is unique, as an asymptomatic child sneezed out the proglottids of the parasite from his nose. After the full course of antihelminthic drug the patient excreted a whole worm in his stool.

[One case of human nasal myiasis]

Human myiasis is caused by the parasitic maggots of flies. We report a case of nasal myiasis in a 37-year-old woman in Henan. The patient presented with nasal foreign-body sensation, nansal itching sneezing, snuffle and such allergic symptoms in nasal cavity. Based on maggots that were bowed from the right nasal cavity, a detailed endoscopic examination, sinus CT scan and identification of the maggot's species done by parapsychologists of the parasitology teaching and reseach section of the Zhengzhou University School of Medicine, the diagnosis of human nasal infestation by oestrus ovis was definited.

Oral manifestations in the American tegumentary leishmaniasis

Introduction

American tegumentary leishmaniasis (ATL) can affect the skin or mucosa (mucocutaneous leishmaniasis – MCL) including the oral cavity. MCL oral lesions are often confused with other oral diseases, delaying diagnosis and specific treatment, and increasing the likelihood of sequelae. Thus, increasing the knowledge of the evolution of ATL oral lesions can facilitate its early diagnosis improving the prognosis of healing.

Objectives

Evaluate the frequency of ATL oral lesion and describe its clinical, laboratory and therapeutic peculiarities.

Methods

A descriptive transversal study was carried out, using data from medical records of 206 patients with MCL examined at the outpatient clinics-IPEC-Fiocruz between 1989 and 2013. Proportions were calculated for the categorical variables and the association among them was assessed by the Pearson's chi-square test. Measures of central tendency and dispersion were used for the continuous variables and their differences were assessed by both parametric (t test) and non parametric (Mann-Whitney) tests. P-values <0.05 were considered as significant.

Results

The most affected site was the nose, followed by the mouth, pharynx and larynx. Seventy eight (37.9%) have oral lesions and the disease presented a lower median of the evolution time than in other mucous sites as well as an increased time to heal. The presence of oral lesion was associated with: the presence of lesions in the other three mucosal sites; a smaller median of the leishmanin skin test values; a longer healing time of the mucosal lesions; a higher recurrence frequency; and a smaller frequency of treatment finishing and healing. When the oral lesion was isolated, it was associated with an age 20 years lower than when the oral lesion was associated with other mucosal sites.

Conclusion

Considering the worst therapy results associated with the presence of oral lesions, we suggest that lesions in this location represent a factor of worse prognosis for MCL.

Merizocotyle euzeti sp. n. (Monogenea: Monocotylidae) from the nasal tissue of three deep sea skates (Rajidae) in the southwestern Atlantic Ocean

A new species of Merizocotyle Cerfontaine, 1894 (Monogenea: Monocotylidae) is described from the nasal tissues of three deep sea rajid skates: the southern thorny skate, Amblyraja doellojuradoi (Pozzi), broadnose skate, Bathyraja brachyurops (Fowler), and yellownose skate, Zearaja chilensis (Guichenot), collected off Buenos Aires Province, Argentina, southwest Atlantic Ocean. Two additional species of sympatric rajid, the white-dotted skate, Bathyraja albomaculata (Norman), and the Patagonian skate, Bathyraja macloviana (Norman), were also examined but no merizocotylines were found. The taxonomy of the Merizocotylinae is not widely accepted and, as a result, the status of Thaumatocotyle and Mycteronastes, and their proposed synonymy with Merizocotyle are currently under discussion. The new species differs from its congeners by having a unique haptoral structure, 6 peripheral loculi that are asymmetrically arranged (one much smaller, indistinctly located in the left or right side of the haptor). The presence of the new species in three sympatric species of Rajidae belonging to distinct genera and subfamilies, as well as its absence in sympatric congenerics indicates the lack of phylogenetic host specificity. Host ecology and geographical distribution appear to be more important than host phylogeny in determining the distribution of this parasite across potential hosts in the region. This constitutes the first record of Merizocotyle in the southwestern Atlantic Ocean.

Nasal, oral and ear swabs for canine visceral leishmaniasis diagnosis: new practical approaches for detection of Leishmania infantum DNA

Background

The aim of this study was to evaluate the potential use of nasal, oral, and ear swabs for molecular diagnosis of canine visceral leishmaniasis (CVL) in an endemic urban area in Brazil.

Methodology/Principal Findings

Sixty-two naturally infected and ten healthy dogs were enrolled in this study. Bone marrow aspirates, peripheral blood, skin biopsy, and conjunctival, nasal, oral, and ear swabs were collected. All samples, except blood, were submitted to conventional PCR (cPCR) and quantitative real time PCR (qPCR) to detect and quantify Leishmania infantum DNA, respectively. All dogs were submitted to thorough clinical analysis and were included based on a combination of serological (ELISA immunoassay and immunofluorescent antibody test) and parasitological methods. The cPCR positivity obtained from nasal swab samples was 87% (54/62), equivalent to those from other samples (P>0.05). Positive results were obtained for 79% (22/28) in oral swabs and 43% (12/28) in ear swab samples. A significant difference was observed between these data (P = 0.013), and the frequency of positive results from oral swab was equivalent to those from other samples (P>0.05). The use of ear swab samples for cPCR assays is promising because its result was equivalent to skin biopsy data (P>0.05). The qPCR data revealed that parasite loads in mucosal tissues were similar (P>0.05), but significantly lower than the parasite burden observed in bone marrow and skin samples (P<0.05).

Conclusions

Nasal and oral swab samples showed a high potential for the qualitative molecular diagnosis of CVL because their results were equivalent to those observed in samples collected invasively. Considering that mucosae swab collections are painless, noninvasive, fast and practical, the combination of these samples would be useful in massive screening of dogs. This work highlights the potential of practical approaches for molecular diagnosis of CVL and human leishmaniasis infections.

Visceral leishmaniasis (VL) is an important public health problem in different regions of the world. It presents high lethality in human cases without suitable treatment and is considered one of the most important disorders in dogs, the main domestic reservoir of the etiological agent of VL (Leishmania infantum). Most cases of VL in Latin America occur in Brazil, and control campaigns have not shown satisfactory results. The diagnosis of human and canine infection is critical for making decisions regarding surveillance and control policies. In this work, we propose a non-invasive collection method of mucosal and epithelial cells for the molecular diagnosis of canine VL by conventional polymerase chain reaction (cPCR) and for the estimation of parasite load by quantitative real time PCR (qPCR). We used nasal, oral, and ear swabs as practical, simple, painless and fast alternatives for collecting samples. These procedures are according to the need of more simplified methods for detecting L. infantum infection by using robust diagnostic techniques such as cPCR and qPCR. Additionally, potential applications for diagnosing human VL are highlighted.

Nasal myiasis due to Lucilia sericata (Meigen, 1826) from Iran: a case report

Although not very common, human myiasis occurs more in developing tropical countries. A variety of dipterans cause nasal myiasis including the family Caliphoridae. In this report a case of nasal myiasis due to Lucilia sericata is reported for the first time, in a 74-year old patient from Mazandaran Heart Centre, North of Iran. The patient was originally admitted to the Mazandaran Heart Centre due to cardiac arrest and cerebral ischemia with diminishing consciousness. Because of the emergence of large number of maggots from his left nostril and the suspicion of infectious diseases, he was referred to the ICU of the Razi Infectious Diseases Hospital the next day. The larvae were identified as L. sericata. The conditions of the patient were medicated and the myiasis was treated by washing with 2% solution of xylocaine and oral administration of 2 mg tablets of ivermectin.

Nosocomial nasal myiasis in an intubated patient

We report a case of nasal myiasis caused by Sarcophaga spp., noted during hospitalization. A 74-year-old man was admitted with non-ST-elevation myocardial infarction. The patient underwent coronary arterial bypass surgery and was then mechanically ventilated by means of a nasotracheal tube for the next 8 days. After extubation, a total of seven maggots were retrieved from both nostrils. The larvae were removed and reared to mature flies, which were identified as Sarcophaga peregrina. From the clinical course and the fly's life cycle, it was concluded that the infestation was hospital-acquired.

Sheep and goat immune responses to nose bot infestation: a review

Oestrus ovis L. (Diptera: Oestridae) is a cosmopolitan agent of myiasis in sheep and goats. The parasitic phase begins after adult females deposit first-stage larvae (L1) into the nostrils of hosts; these larvae develop into L2 and L3 in the nasal and sinus horn cavities. Sneezing and nasal discharges are the major clinical signs in infected animals. The pathogenesis of O. ovis infection is caused by: (a) the trauma resulting from the mechanical action of spines and hooks during larval movement on mucosal membranes, and, more importantly, (b) an allergenic reaction provoked by molecules excreted/secreted by larvae, of which salivary antigens are those mainly recognized by the host's immune system. The recruitment of immune reactive cells increases gradually from the nasal to sinus cavities in infected hosts. Mast cells, eosinophils, macrophages and lymphocytes are always more numerous in infected than non-infected animals. Humoral (antibody) systemic response of immunoglobulin G (IgG) usually reaches seroconversion 2-4 weeks post-first infection and the highest levels are observed during the development of L2 and L3 larvae. Local antibody responses include specific IgG, which has been found to negatively correlate with larval survival and development. Hypersensitivity reaction, immunomodulation, immunization trials and mixed infections of O. ovis and helminths are discussed.

Tyrannobdella rex n. gen. n. sp. and the evolutionary origins of mucosal leech infestations

BACKGROUND

Leeches have gained a fearsome reputation by feeding externally on blood, often from human hosts. Orificial hirudiniasis is a condition in which a leech enters a body orifice, most often the nasopharyngeal region, but there are many cases of leeches infesting the eyes, urethra, vagina, or rectum. Several leech species particularly in Africa and Asia are well-known for their propensity to afflict humans. Because there has not previously been any data suggesting a close relationship for such geographically disparate species, this unnerving tendency to be invasive has been regarded only as a loathsome oddity and not a unifying character for a group of related organisms.

PRINCIPAL FINDINGS

A new genus and species of leech from Perú was found feeding from the nasopharynx of humans. Unlike any other leech previously described, this new taxon has but a single jaw with very large teeth. Phylogenetic analyses of nuclear and mitochondrial genes using parsimony and Bayesian inference demonstrate that the new species belongs among a larger, global clade of leeches, all of which feed from the mucosal surfaces of mammals.

CONCLUSIONS

This new species, found feeding from the upper respiratory tract of humans in Perú, clarifies an expansion of the family Praobdellidae to include the new species Tyrannobdella rex n. gen. n. sp., along with others in the genera Dinobdella, Myxobdella, Praobdella and Pintobdella. Moreover, the results clarify a single evolutionary origin of a group of leeches that specializes on mucous membranes, thus, posing a distinct threat to human health.

[New hosts for the nasal mite Rhinonyssus rhinolethrum (Trouessart) (Gamasida: Rhinonyssidae) in Brazil]

The black-necked swan, Cygnus melanocoryphus, and the ringed teal, Callonetta leucophrys, are reported as new hosts for the nasal mite Rhinonyssus rhinolethrum (Trouessart) in Brazil.

[Investigation of Demodex sp. using cellophane tape method among university students]

Demodex sp. is an obligatory ectoparasite of pilosebaceous units in humans. This study was carried out in order to investigate the frequency of Demodex sp. among high school students. For this purpose 75 women and 96 men, making a total of 171 students, were studied. Cellophane-tape preparations taken from their face, especially at the base of the nose, underside of the jaw and the side of the forehead, were examined microscopically. Demodex sp. was found to be positive in five (2.9%) cases.

Comparison of Demodex folliculorum density in haemodialysis patients with a control group

BACKGROUND

Demodex folliculorum (DF) is resident in human pilosebaceous follicles. Mite density is low in healthy skin. Many cases of demodicosis in association with immunosuppression have been reported. Patients undergoing haemodialysis are also immunosuppressed.

OBJECTIVE

We aimed to compare the Demodex folliculorum density in haemodialysis patients and healthy subjects.

METHODS

Mite density of 87 patients undergoing haemodialysis was compared with that of age- and sex-matched controls. Two samples of standardized skin surface biopsies were taken from each subject from the forehead, cheek and nose. The number of mites counted on the surface area of 1 cm2 was accepted as the density of DF. The length and width of mites were measured by oculometer.

RESULTS

DF density was found in 17 (19.54%) of the 87 dialysis patients and in 9 (10.34%) of 87 controls. A mean mite density of 5.11+/-5.65 was found in dialysis patients and of 2.55+/-1.6 in controls. Differences between the two groups in mite density were not statistically significant (P=0.13). There was also no significant difference in mite length between the two groups (P=0.06). There was, however, a significant difference in mite width (P=0.018).

CONCLUSION

Despite the presence of sebaceous gland atrophy in haemodialysis patients, the higher density of DF in these patients than controls supports the supposition that this mite can increase immunosuppression.

Unilateral epistaxis after swimming in a stream

A 55-year-old Chinese woman presented with a 3-week history of unilateral left-sided epistaxis and nasal obstruction. She had swam in a freshwater stream 1 month prior to the onset of symptoms. Endoscopic examination revealed a live leech at the left middle meatus with a large part of its body inside the left maxillary antrum. Local anaesthetic was applied to anaesthetise the leech and facilitate removal. Magnetic resonance imaging performed following removal confirmed that no other leeches were present in the sinonasal area. The endoparasitism might have persisted because of the inconspicuous site of infestation and the absence of pain. This form of leech infestation has not been previously reported.

Feline leishmaniasis due to Leishmania (Leishmania) amazonensis in Mato Grosso do Sul State, Brazil

A case of leishmaniasis in a domestic cat (Felis domesticus) is described. The animal showed a single, nodular lesion on the nose and many nodules of different size on the ears and digital regions of all the paws. Diagnosis was made by microscopic detection of amastigotes in Giemsa-stained smears from the lesions. By monoclonal antibodies the aetiological agent was identified as Leishmania (Leishmania) amazonensis, one of the seven species implicated in human leishmaniasis in Brazil. The clinical signs in feline leishmaniasis are unspecific and similar to those observed in other diseases such as cryptococcosis and in sporotrichosis, commonly found in cats. Leishmaniasis should therefore, be added to the differential diagnosis by feline veterinary practitioners and adequate investigations should carried out for dermal leishmaniasis in the area where the feline infection is detected.

Use of laser rhinoscopy to treat a nasal obstruction in a captive California sea lion (Zalophus californianus)

Laser rhinoscopy was used to treat a nasal obstruction in a captive California sea lion (Zalophus californianus). The rehabilitated, adult, female sea lion developed mucopurulent, intermittent, bilateral nasal discharge and functional nasal obstruction 20 mo after acquisition by the Aquarium of the Pacific in Long Beach, California. A 3-mm-thick soft tissue structure spanning the region between the soft and hard palates, a deviated nasal septum, and several nasopharyngeal polyps were identified. Biopsies and cultures of the obstructive web showed ulcerative granulation tissue with suppurative inflammation, bacterial infection, and a partial section of an arthropod larva (not speciated). Laser rhinoscopy was performed to relieve the caudal nasopharyngeal obstruction and ablate the polyps. The sea lion appeared to breathe through the nares with lessened nasal discharge for a period of 6 wk after laser therapy, but within 8 wk the mucopurulent nasal discharge returned, the obstruction had reformed, and the sea lion was euthanized. Postmortem examination confirmed antemortem diagnoses of caudal nasopharyngeal obstruction secondary to inflammatory tissue; however, no additional sections of arthropod parasites were located microscopically.

Investigating demodex in forensic autopsy cases

Demodex is an ectoparasite living in the skin as a nonpathogen or a pathogen. It is also known that demodex acts as a vector of pathogenic microorganisms. In this study, we have investigated the rate of occurrence and vitality of demodex in forensic autopsies that have a high risk of contamination by infected organisms. The study, which was cross-sectional, conducted on 100 autopsy cases: 77 of the bodies were male and 23 female. The average age was 41. The samples were taken from the forehead, nose, cheeks, eyelashes and the temporal areas using the standardized skin surface biopsy and hair epilation techniques that were modified for this study. The data obtained were assessed statistically. Demodex was determined in 10% of all the cases. The cases revealed that demodex increased in old age and was more frequently seen in people with fair complexion. It was most frequently found in the forehead and the cheek. The longest postmortem interval in the positive cases was 55 h. The relationship between the postmortem interval and the presence of demodex was not statistically significant. Considering the fact that demodex, which is transmitted from human to human through skin contact, acts as a vector of pathogenic organisms and can stay alive in dead bodies for a long time, we think that the personnel performing autopsies without taking the necessary precautions are under risk.

Towards a lower prevalence of Oestrus ovis infections in sheep in a temperate climate (south west France)

Oestrus ovis larvae are obligatory parasites of the nasal and sinus cavities of sheep and goats. In the temperate climate of western Europe, fly attacks occur between May and October and the first stage larvae arrest their development within the host between October and February. Oestrosis clinical signs such as nasal discharge and sneezing are well known by sheep breeders in southwest France. According to veterinarian recommendations, most of them treat their animals with long lasting fasciolicides once a year at least, mainly during the fly activity period and at the beginning of the hypobiotic period (when the parasitic population is only constituted of larvae). The consequences of these therapeutic programs were analysed in a local slaughterhouse by larval counts. Both prevalence and intensities of O. ovis infections decreased between 1989-1991 (before the use of systematic treatments) and 1996-1998 (after the spread of these treatments). The use of systematic treatments during the fly activity period and the beginning of the hypobiotic period seems to be very efficient in O. ovis control and could theoretically lead to a possible 'eradication' program as with cattle hypodermosis. Nevertheless the presence of parasites in apparently healthy goats, the possibility for a fly generation to develop before the first treatment in July-August and the succession of several fly generations all around the year in southern Mediterranean and tropical countries will maintain O. ovis infections. Furthermore, there are increased concerns about drug residues on consumer health and environment and this is the basis for the prospect of alternative strategies in O. ovis control.

Sheep oestrosis (Oestrus ovis Linné 1761, Diptera: Oestridae) in Sardinia, Italy

Oestrosis, the nasal myiasis of sheep and goats, is caused by the larvae of Oestrus ovis L. 1758 (Diptera, Oestridae) that develop from the first to the third stage larva in the nasal cavities and frontal sinuses of affected animals. The authors report the results of an epidemiological study of oestrosis of sheep in Sardinia, Italy. Heads of 6-month to 10-year-old Sardinian sheep (n=566) from 124 free-ranging flocks were examined for the presence and location O. ovis larvae from December 1996 to November 1997. Larvae were collected, counted, and larval stages were identified. O. ovis larvae were found in 100% of examined flocks and in 91% (514/566) of examined sheep. The monthly prevalence ranged from 69% in May to 100% in July. First stage larvae were found in 82% (463) of all heads examined, second stage larvae in 65% (367) and third stage larvae in 10% (56). The majority of sheep harboured first stage larvae, with prevalences of over 80% throughout most of the study period. The prevalence of O. ovis found in this study of Sardinian sheep is the highest reported in the Mediterranean area. The high percentage of first stage larvae found throughout the entire study period may be due to a brief period of decreased rate of larval maturation, in particular in December 1996 (96%) and January-October 1997 (94%). Third stage larvae were consistently present, often however, with extremely low prevalences compared to total larval burden.

[Human nasal myiasis due to Oestrus ovis]

One case of human nasal myiasis caused by second and third instar larvae of Oestrus ovis was observed in Lille (North France). Oestrosis is a common myiasis of sheep and goats in Mediterranean and Tropical countries. The authors examine the oestrosis pathogenesis in the usual host (sheep) or in humans, and analyse the epidemiology, the symptomatology and the treatment of human oestrosis.

Parasitic sinusitis and otitis in patients infected with human immunodeficiency virus: report of five cases and review

We describe five cases of parasitic sinusitis and otitis in patients infected with human immunodeficiency virus (HIV) and review 14 reported cases. The pathogens identified in our group of patients included agents such as Microsporidium, Cryptosporidium, and Acanthamoeba species. The clinical features common to these patients included a long history of HIV seropositivity associated with advanced immunosuppression and multiple opportunistic infections as well as long-standing local symptoms refractory to multiple courses of antibacterial agents. Symptoms often included fever and chills in addition to local tenderness and discharge. Invasive diagnostic procedures were necessary to obtain the final diagnosis and to initiate appropriate therapy. Although most patients responded at least partially to specific therapy, relapses and recurrences were frequent in patients who did not receive long-term suppressive therapy. The general outcome for HIV-infected patients with parasitic sinusitis and otitis was poor; however, deaths were generally associated with other complications of the underlying HIV infection.

Laryngeal involvement during post kala-azar dermal leishmaniasis in India

Post kala-azar dermal leishmaniasis (PKDL) involving the mucus membranes is relatively rare on the Indian sub-continent. We describe 3 cases of PKDL presenting with hoarseness of voice. In one case the skin, nasal, oral, oropharyngeal and laryngeal mucosa had nodular and nodulo-ulcerative lesions; in the 2 other cases, genitalia and anorectal mucosa were also affected. Laryngoscopic examination revealed nodular lesions on the vocal cords. Biopsy smear and culture confirmed their leishmanial origin.

Efficacy of ivermectin controlled-release capsules for the control and prevention of nasal bot infestations in sheep

OBJECTIVE

To investigate the therapeutic and prophylactic efficacy of an ivermectin controlled-release capsule against nasal bots (Oestrus ovis) in sheep.

DESIGN

Trial 1--A pen study with controls. Trial 2--A field study with controls.

ANIMALS

Trial 1--Forty Merino wethers with natural infestations of nasal bot were used. Trial 2--One hundred nasal bot-free wethers were used.

PROCEDURE

Trial 1--Ten randomly selected animals were slaughtered and the heads split and examined to confirm bot infestation. Fifteen animals were allocated to untreated controls and 15 to treatment with a controlled-release capsule delivering ivermectin at > or = 20 micrograms/kg/day for 100 days. Twenty-nine days after treatment the sheep were killed and examined for nasal bots. Trial 2--Nasal bot-free sheep were allocated to two groups of 45 animals. One group was untreated the other sheep were treated with capsules as above. The sheep were grazed as a single group exposed to natural challenge from O ovis. Ninety days after treatment the animals were slaughtered and examined for nasal bot infestation.

RESULTS

Trial 1--Live O ovis larvae were recovered from 60% of control sheep. No live larvae were collected from treated sheep. Trial 2--Forty-one percent of untreated sheep harbored nasal bot infestations. No live larvae were collected from any treated animal.

CONCLUSION

Treatment with a single ivermectin controlled release capsule was 100% effective against existing infestations of O ovis and as a prophylactic treatment for this parasite.

Efficacy of moxidectin as a 1% injectable solution and a 0.1% oral drench against nasal bots, pulmonary and gastrointestinal nematodes in sheep

Thirty ewes, 3-10 years old, known to be naturally infected with internal parasites, were allocated to three homogeneous groups of ten ewes each based on faecal nematode egg counts. The following experimental treatments were administered on Day 0: (A) moxidectin 1% injectable solution at 0.2 mg kg-1 body weight; (B) moxidectin 0.1% oral drench solution at 0.2 mg kg-1 liveweight; (C) untreated control. Faecal samples were taken on Days -7, 0, 1, 2, 3, 7, 14, 21, 28 and 35 to obtain counts of nematode eggs. One-half of the ewes in each treatment group were slaughtered 14 days after dosing, while the remainder were slaughtered 35 days after treatment to count the numbers of nasal bots, pulmonary nematodes and gastrointestinal nematodes. Moxidectin 1% injectable solution and moxidectin 0.1% oral drench solution were highly effective against gastrointestinal nematodes and against a variable infection of Dictyocaulus filiaria. Moxidectin 1% injectable solution was effective against first stage larvae of Oestrus ovis, whereas moxidectin 0.1% oral drench was ineffective.

Vile bodies: an endoscopic approach to nasal myiasis

Nasal myiasis is the infestation of the nasal cavities by larvae (maggots) of Diptera flies. Several species of flies deposit their ova in the nose and the larvae feed on the host's tissues. We present a case of nasal myiasis by larvae of Oestrus ovis--Sheep Nasal Bot Fly. The larvae of Oestrus ovis are well known parasites in the nasal cavities and paranasal sinuses of sheep and goat. In Britain very rarely larvae may be deposited in the eye, nostrils or outer ear of man, usually husbandry workers. Reputedly, the larvae never survive beyond the first stage with acute catarrhal symptoms lasting only a few days. This is the first reported case in the UK of an urban-dwelling patient infected by mature, third instar larvae of O. ovis. His nasal infestation resolved after endoscopic removal of the live maggots.

Identification of a nasal nematode (Eucoleus boehmi) in greyhounds

Eggs of Eucoleus boehmi were recovered from the faeces of greyhounds from three breeding farms and four racetrack kennels and from those of four greyhounds submitted for necropsy. Diagnosis was dependent on differentiation of the eggs of E. boehmi, E. aerophilus and Trichuris vulpis. Quantitative fecal examinations conducted weekly for 24 weeks in one greyhound suggested that the egg shedding pattern of E. boehmi is cyclical. Nasal swabs failed to reveal eggs of E. boehmi, but nasal washings gave positive results. Because of its small size (15-40 mm) its location within the epithelial lining of the nasal mucosa, turbinates, and sinuses, and difficulty in differentiating the bipolar plugged eggs, E. boehmi probably occurs more often than is currently diagnosed.

Rodents are not a source of endogenously-produced, fecally-transmitted Caryospora bigenetica oocysts

Fifteen Swiss-Webster mice (Mus musculus) and eight cotton rats (Sigmodon hispidus) were inoculated orally with Caryospora bigenetica oocysts. Feces from these animals were collected from 0 to 180 days postinoculation (DPI) and examined for endogenously-produced oocysts using Nomarski microscopy. Oocysts were recovered from mouse feces at 0, 1, 2, 3, 5, 7, 8, 10, and 14 DPI, and from cotton rat feces at 1, 2, and 9 DPI. The recovered oocysts were determined to be from the original inocula due to the presence of thick walls, polar granules, and Stieda and substieda bodies. All animals exhibited clinical signs at 8 DPI. Developmental stages of C. bigenetica were identified in various tissues of seven cotton rats found dead at 9, 10, 11, 12, and 13 DPI. Caryocysts were found in muzzle, tongue, footpad, scrotum, and rectum of mice and cotton rats at 30 DPI. Fecal samples collected from mice on 0, 8, 10, 12, 14, 16, and 18 DPI, and from cotton rats on 0, 9, 11, 13, 15, and 17 DPI were injected subcutaneously into 13 mice. Of the 13 mice, a Caryospora infection was observed only in the mouse inoculated with 0 DPI mouse feces. We propose that endogenously-produced C. bigenetica oocysts are not fecally-transmitted by Swiss-Webster mice or cotton rats.

Epidemiology of Oestrus ovis in southwest France

From July 1989 to June 1990, 555 heads of adult sheep obtained from Pamiers slaughterhouse (southwest France) were examined for infestation by Oestrus ovis. Infestation was present in 65% of the heads and the mean larval burden per positive case over the year was 24.8. The monthly prevalence rate varied from 44% in April to 88.2% in November. There are usually three generations of O. ovis each year: the first in March-April, the second in June-July and the last in September-October. There was no fly activity in winter and during the hottest months of summer. On the other hand, nearly all the larvae overwintered as the first stage. This study emphasizes the seriousness of the problem in the region and the authors recommend three strategic treatments per year during periods of high fly activity.

An extended proof of migration routes of immature parasites inside hosts: pathways of Nippostrongylus brasiliensis and Strongyloides ratti in the rat are mutually exclusive

Rigorous proofs applicable to the routes of migration of Strongyloides ratti and Nippostrongylus brasiliensis skin-penetrating juveniles inside the rat are extended. By applying the inequality principle (Tindall & Wilson, 1988) it was confirmed with a probability of error of 1 in 10(10) that N. brasiliensis larvae applied to the skin passed through the lungs on their way to the intestine. Taking the analysis further, migrating larvae of S. ratti or N. brasiliensis were extracted from the nose or lungs, respectively, of donor rats and transferred to recipients by stomach tube to assay their ability to colonize the intestine. Results showed that (a) changes undergone by each parasite in its proven, specific transit site were essential before larvae could establish in the intestines of recipients, (b) these changes could be monitored by morphological criteria, and [corrected] (c) these changes were not completed until larvae had been in the nose or lung for a significant period. It follows from (c) that anywhere in the body of the host, termed a 'nursery', that supports a substantial amount of this mandatory development must be detectable by the conventional procedure of sampling at autopsy. Conversely, absence of parasites judged by sampling at autopsy is positive proof that a site is not a nursery when sampling is timed in relation to reliable estimates of overall kinetics (Tindall & Wilson, 1990), and with control information on the efficiency of sampling. Comparative data from sampling at autopsy using the same extraction techniques for both species met these criteria: they demonstrated that no part of the head of the rat was a nursery for N. brasiliensis, and that the lung did not serve in this capacity for S. ratti.(ABSTRACT TRUNCATED AT 250 WORDS)

Occurrence of Demodex in nose follicles of outpatients attending an otorhinolaryngology clinic

The occurrence of Demodex in sebum from nasolabial folds was studied in fifty outpatients attending an otorhinolaryngology clinic. Thirty-one male and nineteen female patients aged fifteen to eighty years were examined. Twenty percent (eight men and two women) showed positive findings, demonstrating one to six parasites per specimen. A higher detection rate was found in older patients, and more mite particles were seen in subjects with otitis media. It is suggested that examination of nasolabial folds may serve as a screening test for the possible presence of Demodex in the ears.

Leishmania major: the suitability of East African nonhuman primates as animal models for cutaneous leishmaniasis

The susceptibility of four species of East African nonhuman primates to experimental infection with Leishmania major was investigated. Four Syke's monkeys (Cercopithecus mitis), two vervet monkeys (Cercopithecus aethiops), two baboons (Papio cynocephalus), and two brown bushbabies (Galago garnettii) were each inoculated intradermally on the left eyelid, left ear, and nose with 0.1 ml of medium containing 1 x 10(7) promastigotes of a characterized L. major strain. All the nonhuman primates except the bushbabies developed erythema and conspicuous nodules on the eyelids and ears by 3 weeks PI. The nodules increased rapidly in size and ulceration was evident on the eyelids and ears by 49 days PI in the vervets, Syke's, and baboons. The aspirates were positive in culture or smears at 35, 49, 63, and 77 days PI. No parasites were observed in cultures or smears at 92, 105, 128, 147, and 161 days PI. The lesions in these animals began resolving by 84 days PI and were completely healed by 112 days PI. The exception was one baboon in which lesion healing did not start until around 147 days and was completely healed by 182 days PI. Cultures from the liver failed to demonstrate visceralization of the parasite in any of the animals throughout the 68 weeks of the experiment. Challenge with the same strain of L. major 6 months PI, corresponding to about 3 months after self cure, failed to produce infection in any of these experimental hosts. All the nonhuman primates except the bushbaby when challenged with the same strain of L. major at 12 months PI developed lesions and were positive for parasites at 14 and 28 days PI. Positive cultures were obtained from the eyelid and ear of one vervet up to 42 days PI. However, the lesion sizes in all these animals were smaller than in the initial infection and did not ulcerate. The nodules disappeared within 6 to 8 weeks as compared to 16 weeks in the initial infection. The histopathological appearance of the lesions varied from diffuse infiltration of plasma cells and lymphocytes which increased progressively to granulomata with epitheloid cells. This study shows that the vervets, Syke's, and the baboons are equally susceptible to L. major infection, while bushbabies are refractory. The vervets, Syke's, and baboons demonstrate a self-healing phenomenon within about 3 months which is comparable to that observed in humans infected with L. major. These three species of nonhuman primates are therefore considered as suitable models for drug or vaccine trials against human zoonotic cutaneous leishmaniasis.

Prevalence and host-parasite list of some nasal mites from birds (Acarina: Rhinonyssidae, Speleognathidae)

A survey of nasal mites, primarily from birds in Texas, was reported and comparisons with the other major studies were made. Of 103 host species examined, 40 were parasitized, and of 502 individual birds examined, 87 were parasitized (17% prevalence). It was shown that the prevalence of infection was significantly dependent on the bird taxa examined, which indicates that the evolution of the hosts has affected the nasal mites' ability to parasitize their avian hosts. It was also shown that the prevalence of rhinonyssid nasal mites in their hosts seems to differ significantly between geographic regions.

Further studies on the resistance to Onchocerca microfilariae in CBA mice

Various factors governing resistance to the microfilariae (mf) of Onchocerca lienalis in mice have been examined to provide baseline data for use of this model in immunological studies. The survival of mf during a primary infection followed a similar course in the skin from most anatomical regions of the body. Mice were highly resistant to secondary infections, manifested by parasite densities over the body that were reduced by 83-100% compared with controls. Recoveries of mf from the ears, used in later experiments, were a representative measure of parasite survival in other skin sites. The resistance to challenge induced by a primary infection was not dependent on the route of administration (intravenous, intraperitoneal, subcutaneous and intramuscular) of the latter and was apparently systemic. Primary infections of various durations that were chemically-abbreviated conferred maximum protection when of 15 days or longer (95-97%) and substantial resistance when of only 7 days (84%). Similar levels of protection were demonstrated in mice that were sensitized with single or multiply-divided mf doses, or challenged in a similar manner. Primary infections containing as few as 20 mf induced almost the same degree of protection (80%) as 50 to 10,000 mf (88-97%). Apparently, resistance to re-exposure with O. lienalis mf is mediated by a highly effective mechanism(s) in CBA mice.

Extraintestinal development of Caryospora simplex (Apicomplexa: Eimeriidae) in experimentally infected mice, Mus musculus

Developmental stages of Caryospora simplex were found in connective tissue of the cheek, tongue, and nose of Swiss-Webster and C57 BL/6 mice (Mus musculus) from 8 through 70 days after oral inoculation with 50,000 or 250,000 oocysts, or 60,000 free sporocysts of the same species obtained from an Ottoman viper, Vipera xanthina xanthina. The earliest developmental stages were seen on day 8 post-inoculation (PI) and consisted of two types of meronts and gamonts (undifferentiated sexual stages). Gamonts, microgametocytes, macrogametes, and unsporulated oocysts were found on days 10 and 12 PI. Fully sporulated, thin-walled oocysts containing eight sporozoites surrounded by a thin sporocyst membrane were first seen 12 days PI. Monozoic cysts (caryocysts) were first seen 12 days PI and appeared fully viable throughout the duration of the study, 70 days PI. Four mice injected intra-peritoneally with 150,000 free sporozoites and killed 12 days PI contained unsporulated and sporulated oocysts in connective tissues of the cheek, tongue, and nose, suggesting that sporozoites may be carried to the site of infection via the lymphatic/circulatory system. Four cotton rats, Sigmodon hispidus, inoculated orally with 250,000 oocysts all had unsporulated and sporulated oocysts of C. simplex in connective tissue of the cheek, tongue, and nose when killed on day 12 PI, indicating extraintestinal development in the secondary host is not species specific. This is the first report of a heteroxenous coccidium with both asexual and sexual development in the primary (predator) and secondary (prey) hosts.

Inefficacy of metronidazole in experimental infections of Leishmania donovani, L. mexicana, and Trypanosoma brucei brucei

Metronidazole has been claimed in several earlier reports to be active in human cases of leishmaniasis and trypanosomiasis. Its efficacy against the protozoa causing these diseases was tested in hamsters infected with Leishmania mexicana or L. donovani, and in mice infected with Trypanosoma brucei brucei. In separate experiments, hamsters were either inoculated intradermally into the nose with 5 million amastigotes of L. mexicana or intracardially with 10-30 million amastigotes of L. donovani, and mice were infected intraperitoneally with 30 million T. b. brucei. Metronidazole was administered in four oral doses on alternate days for a total of 375 mg/kg to hamsters and 500 mg/kg to mice. Sodium stibogluconate (Pentostam) served as a positive control. In hamsters the extent of infection was assessed by the appearance of flagellates in blood agar cultures of nose and spleen, by counting amastigotes in nose and liver impression smears, and by measuring the size of nose lesions. Ultrastructure of nose lesions before and after treatment with metronidazole or Pentostam was also evaluated. Infection in mice was assessed by the extent of parasitemia and/or survival to 30 days. In no case did metronidazole-treated animals differ from untreated controls. Metronidazole shows no activity against experimental infections of leishmaniasis or trypanosomiasis in these animal models.

Incidence of free-living amoebae in the nasal passages of local population in Zaria, Nigeria

Following the observation of cases of primary amoebic meningoencephalitis (PAME) during the dusty harmattan period in Zaria, a survey was carried out in randomly selected local populations of Zaria, to find out the incidence of free-living amoebae in the nasal passages. The times of sampling were spaced so as to cover both the rainy (non-harmattan) abd dry (harmattan) seasons. In all 1250 individuals were sampled, and were grouped in the three age groups of above 18 years, between 4 and 18 years and below 4 years. The overall incidence was 4.2% (52 out of 1250). There was no marked difference in the three age groups studied. The incidence rate in males was 4.8% (30 of 630) and that in females was 3.5% (22 of 620). Nine different species of free-living amoebae were isolated. Six belonged to the Genus Hartmannella, two to the genus Naegleria, and one to the genus Schizopyrenus. Three species were found to be pathogenic for mice: H. culbertsoni, H. rhysodes and N. fowleri. It was observed from this study that a significant percentage of the Zaria population carry free-living amoebae in the nasal passages. The monthly incidence rate in population ranged from 1.8 to 3.1% during the rainy (non-harmattan) season whereas in the dry (harmattan) season it ranged from 4.2 to 7.9%. The highest incidence rate coincided with the peak of the dry (harmattan) season. The possible role of harmattan winds on the nasal carriage as well as the necessity to investigate fully the disease PAME in this environment is discussed.

Incidence of Demodex folliculorum on skin of lids and nose

The incidence of follicle mites (Demodex) has been studied in 206 non-selected subjects by means of adhesive tape impressions on skin during daytime of nose and lids and moist storage of the tape. The incidence was seen to rise with increasing age: 4% in young subjects, 30% in the age group of 20 to 80, and 47% in older. The mite was more often present on the skin of the nose (17%) than on that of the upper lid (8%), while the incidence on the lower lid was between these 2 extremes (13%). A total of 126 Demodex mites were detected (123 Demodex folliculorum and 3 Demodex brevis), all full-grown. Of these, 41% were ghosts. The migration was evenly distributed in all directions within the areas examined. About 0.2% of the mites can be roughly estimated to have migrated at a certain point of time from the follicles of the nose to its skin.

Hospital-acquired myiasis

In three years we encountered two patients with hospital-acquired myiasis, a rarely reported nosocomial problem. Both patients were elderly and had lengthy thoracic surgery in August in the same operating room. Larvae removed from the nares of one patient and from the chest incision of the other were of the same species, Phaenicia serricata. There was no evidence of tissue destruction or invasion in either case. Investigation revealed several factors that contributed to the presence of flies in the operating room. After a presumed environmental access site was closed and insecticide spraying was augmented, no additional cases occurred. This experience illustrates an unusual problem that may confront those responsible for infection control programs.