Detection of Babesia microti parasites by highly sensitive 18S rRNA reverse transcription PCR

Babesia are increasingly appreciated as a cause of transfusion-transmitted infection. Sensitive methods are needed to screen blood products. We report herein that B. microti 18S rRNA is over 1,000-fold more abundant than its coding genes, making reverse transcription PCR (RT-PCR) much more sensitive than PCR. Babesia 18S rRNA may be useful for screening the blood supply.

OCCUPATIONAL, NOSOCOMIAL OR HOSPITAL ACQUIRED TOXOPLASMOSIS

Toxoplasma gondii is protozoan parasite infects wild and domestic animals including birds, cats, sheep, goats, cattle, pigs and poultry. Cats are the definitive host of Toxoplasma and transmitted to other animals or people. There are three forms of T gondii: the tachyzoite (the rapidly reproducing form), the bradyzoite (a slower reproducing form contained in tissue cysts), and the sporozoite (contained in oocysts). The tachyzoite invade cells in the body where it thep multiplies rapidly and can destroy cells. When the cells die, the tachyzoites are released and infect other cells. For this reason, tachyzoites are seen in many tissues and organs throughout the body that are infected during this acute phase of the disease. This is also called the extraintestinal phase of the infection since it can affect all cells outside the intestines in all infected animals. However, only cats have the. intestinal phase of the infection. Two or three weeks after the first infection, the Toxoplasma divides more slowly and a protective membrane forms around the parasite cells. The cyst containing the parasites is called a zoitocyst and the cells inside the cyst are called bradyzoites. The tissue cysts are formed primarily in brain, eye, heart muscle, and skeletal muscle. Bradyzoites persist in tissues for many years, possibly for the life of the host. In cats, Toxoplasma infects the small intestine lining where they reproduce asexually. After a few days of rapid reproduction the cells transform into a sexual form, combine, and become enclosed in a cyst called an oocyst. Oocysts contain the sporozoite form of the Toxoplasma parasite. Gocysts are found in both wild and domestic cats but not in any other animals or birds.

Parasites as etiological factors of nosocomial infections

Nosocomial infections represent an increasing threat to public health. In most cases, they concern patients with risk factors such as taken radio- and chemotherapy, those whose immune system might be suppressed and those who might be HIV-positive. Most studies of the incidence of nosocomial infections ignore parasitic infestations. Based on data from 1,265 intensive care units in 75 countries, it was found that the proportion of parasites in nosocomial infections was 0.48% overall, and 0.25% in Western Europe. An analysis of the available literature indicates an increase in the number of hospital parasitoses.

Prevalence of intestinal parasites among HIV patients in Baringo, Kenya

INTRODUCTION

HIV patients have reduced immune response which makes them more susceptible to different infections. This cross-sectional study was carried out to document the prevalence of intestinal parasites among HIV patients in Baringo County, Kenya.

METHODS

Structured questionnaires were used to collect clinical information after obtaining consent from the participants. Stool samples were collected from 285 respondents for intestinal parasitic examination using direct and formol-ether concentration to detect ova and cysts. Chi-square (X(2)) statistical analysis was used to test level of significance at P = 0.05 using SPSS.

RESULTS

A prevalence of 50.9% of intestinal parasites was recorded. Majority of the parasitic infections were waterborne protozoa with few helminthes. There was an association (P < 0.05) between intestinal parasitic infection and place of residence, agro-ecological location, family size, water source, treatment and reliability and diarrheal status. There was no association (P > 0.05) between age groups and gender with parasitic infection. Parasites identified were Entamoeba histolytica/dispar (58.3%), Giardia lamblia (16.6%), Ascaris lumbricoides (8.6%), Entamoeba coli (5.9%), Taenia saginata (5.3%), Trichuris trichuria (1.9%), Enterobius vermicularis (1.9%) and hookworm (1.3%).

CONCLUSION

There was high prevalence of intestinal parasites, therefore, health education to HIV patients and community health workers on the importance of good environmental sanitation and personal hygiene could curb water, food and individual contamination promoting good management and care of HIV patients, hence improving their health status.

Factors related to missed diagnosis of incidental scabies infestations in patients admitted through the emergency department to inpatient services

OBJECTIVES

Scabies is highly contagious and requires prompt diagnosis and implementation of infection control measures to prevent transmission and outbreaks. This study investigated the clinical and administrative correlates associated with missed diagnosis of scabies in an emergency department (ED).

METHODS

This was a retrospective study of patients with incidental scabies infestations who were admitted to a university hospital via the ED during a 4-year period.

RESULTS

A total of 135 inpatients were identified as having scabies; among them, 111 patients (82%) had visited the ED. Scabies were diagnosed during the ED stay in 39 of 111 patients (35%), while the diagnosis was missed in the ED in 72 patients (65%). Although no geographic clusters suggestive of nosocomial scabies transmission were registered, 160 medical workers and one hospitalized patient received prophylactic treatment due to direct skin-to-skin contact with inpatient scabies cases during the study period. Overcrowding (odds ratio [OR] = 8.4; 95% confidence interval [CI] = 1.9 to 38.0) and time constraints (OR = 8.2; 95% CI = 1.9 to 34.7) in the ED were associated with a missed diagnosis of scabies during ED stay. Patients with lower illness severity scores were at higher risk for failure to diagnose and to treat scabies prior to hospital admission (OR = 5.7; 95% CI = 1.6 to 20.9).

CONCLUSIONS

Missed diagnoses of scabies during ED stay may result in nosocomial spread and increase the unnecessary use of prophylactic treatments. ED overcrowding, time constraints, and less severe illness compromise ED recognition of scabies. Health care workers should be especially alert for signs of scabies infestations under these conditions.

Traumatic myiasis from Sarcophaga (Bercaeal cruentata Meigen, 1826 (Diptera, Sarcophagidae) in a hospital environment: reporting of a clinical case following polytrauma

We present a case of cutaneous myiasis occurring in a hospital environment (nosocomial myiasis) in an patient with serious multiple traumas sustained in a motorcycle accident. The agent responsible for the myiasis was identified as Sarcophaga cruentata (Meigen 1826). The larvae found in the necrotic wound were removed and the necessary environmental measures were taken to avoid further infestation. Although nonocomial myiasis is a form of parasitosis already cited in the in literature, it is a rare event and worthy of attention to aid in identifying parasitosis in hospitalized subjects in order to expedite proper diagnosis and treatment.

Nosocomial scabies

Scabies is a parasitic dermatosis with a worldwide distribution. This infestation affects millions of people annually and may cause large nosocomial outbreaks with considerable morbidity among patients and healthcare workers. Immunocompromised or elderly institutionalized patients admitted with unrecognized crusted scabies are the main source of nosocomial transmission. Factors that facilitate the development of hospital-acquired scabies and nosocomial epidemics are: poor knowledge of scabies epidemiology, unfamiliarity of healthcare workers with atypical presentations, long incubation period, diagnostic delay and incomplete monitoring. Within hospitals, containment of an outbreak relies on the strict implementation of appropriate infection control measures and treatment administration to contacts. It is associated with a considerable working and economic burden.

[Investigation of intestinal parasites in food workers in hospitals in Aydin, Turkey]

Food workers are an important risk group for intestinal parasite contamination and dissemination. In the present study food workers, working in food preparation and distribution in the Adnan Menderes University Hospital, Aydin State Hospital and 82. Yil State Hospital, were screened for the presence of intestinal parasites. Out of 58 food workers 22 were females and 36 were males, and the age of workers ranged from 20 to 56. All workers included in the study answered a questionnaire concerned with their social demographic situation and hygiene habits. Stool specimens and cellophane tape specimens were taken from food workers and studied for the presence of parasites. Stool samples were studied using native Lugol, precipitation by formol ethyl acetate, trichrome and acid fast staining methods. Cellophane tape slides were examined for Enterobius vermicularis with the 10X objective. Out of 58 food workers investi-gated, 17 (29.31%) had at least one parasite; nine had Blastocystis hominis (15.51%), five had E. vermicularis (8.62%), one had Giardia intestinalis (1.72%), one had both Entamoeba histolytica/dispar and Entamoeba coli (1.72%), and one had both E. vermicularis and B. hominis (1.72%). All workers with parasites were treated and taken under surveillance. The oral-fecal route is the main source for intes-tinal parasite contamination. It should be considered that food workers may be the main source for the contamination of hospital workers as well as patients which may cause serious problems especially for the cases with immune deficiency.

Nosocomial pulmonary Rhizopus diagnosed by bronchoalveolar lavage with cytology in a child with acute lymphoblastic leukemia

Rhizopus species is an opportunistic fungus that is contracted by inhalation of aerosolized spores. Early diagnosis is often difficult but is a necessity to prevent rapid progression of the infection that leads to blood vessel invasion by hyphae, causing fatal hemoptysis. A previous case report described the utility of cytologic examination of bronchoalveolar lavage (BAL) fluid in achieving a prompt diagnosis of Rhizopus species in an adolescent patient with diabetic ketoacidosis. The author presents a case that further describes the benefit of performing BAL fluid cytology to help identify fungal morphology characteristics in order to reach an expeditious diagnosis of Rhizopus species in a leukemia patient.

Nosocomial nasal myiasis owing to Cochliomyia hominivorax: a case in French Guiana

Abstract The larval stages of the fly Cochliomyia hominivorax are responsible for myiasis, which primarily affects wounds. We report the case of a bed-ridden patient with dementia who developed right nasal myiasis during his stay at Cayenne Hospital. Progression was favorable, but the nasal pyramid was partially destroyed. In zones where this fly is endemic, particular attention should be given to hospitalized patients with wounds and consciousness problems.

Prevalence and effectiveness of an education program on intestinal pathogens in food handlers

OBJECTIVES

To assess the prevalence of intestinal pathogens and the effectiveness of an education program in food handlers in a tertiary care hospital.

MATERIAL AND METHOD

The prevalence of intestinal pathogens in food handlers was done by stool cultures for bacteria and microscopy for parasites. Treatment was given to those who had a positive stool examination. An education program on the acquisition of the pathogens and their prevention were given by lecture and distribution of handouts. Efficacy of the education program was evaluated by assessing the knowledge and the presence of pathogens before and after the education program.

RESULTS

The study was done from January 2002 to March 2004. Risk factors for acquiring intestinal pathogens among food handlers were high regarding education level, housing, food hygiene and personal hygiene. Diarrheal diseases were common in food handlers and their relatives. Before the education program, 40.8% had intestinal pathogens, bacteria and parasites in almost similar proportions. Most common bacteria were Vibrio parahemolyticus, Plesiomonas shigelloides and Salmonella spp.; Blastocystis hominis, Giardia lambria and Endolimax nana were the frequently found intestinal parasites. Food handlers with the pathogens in stool were treated. After the education program subsequent investigation showed a significant reduction in stool pathogens and parasites but their knowledge and hand hygiene practice did not improve.

CONCLUSION

The present study showed a high prevalence rate of intestinal pathogens in food handlers of a tertiary care hospital. The education program failed to improve their knowledge and hand hygiene practice for the prevention of the pathogens.

Parasites in nosocomial diarrhoea: are they underestimated?

Nosocomial diarrhoea, defined as diarrhoea occurring more than 72 h after hospital admission, is reported to account for <1% of endemic nosocomial infections and 17% of epidemic nosocomial infections. The yield of diagnoses from stool cultures in nosocomial diarrhoea is low, and information regarding the role of parasites is limited. We conducted a study to determine the responsible bacterial and parasitological pathogens from nosocomial diarrhoea cases in our 2000-bed tertiary care facility over a 16-month period. Of 226 patients, Clostridium difficile toxins A or B were present in 5.5%, giardia cysts and/or trophozoites in 4.4%, Blastocytis hominis in 4.4% and Cryptosporidium sp. in 0.5% of samples. In conclusion, parasites should be sought in nosocomial diarrhoea in endemic areas.

Nosocomial malaria and saline flush

An investigation of malaria in a US patient without recent travel established Plasmodium falciparum molecular genotype identity in 2 patients who shared a hospital room. P. falciparum can be transmitted in a hospital environment from patient to patient by blood inoculum if standard precautions are breached.

Nosocomial Oral Myiasis by Sarcophaga sp. in Turkey

We present a case of oral myiasis in a 15-year-old boy with tuberculosis meningitis. The diagnosis was based on the visual presence of wriggling larvae about 1 cm in size and on the microscopic features of the maggots, especially those relating to stigmatic structures. The larvae were identified as third-stage larvae of Sarcophaga sp.

Intestinal parasites may not cause nosocomial infections in psychiatric hospitals

This study was conducted to determine whether nosocomial infections of intestinal parasites occur in psychiatric hospitals. Three fecal specimens were collected from each institutionalized patient in seven psychiatric hospitals of north Taiwan. Saline wet mounts were prepared to examine trophozoites, and the other parasite stages were detected using the formalin-ethyl acetate sedimentation technique. Hospital faculties were asked to complete a questionnaire on the demographic data, health status degree of disability, and recent occurrence of gastrointestinal distress of these patients. Of the 464 patients examined, 8.4% were found to be infected with one or more intestinal parasite species: 6.3% single infections, 1.5% double infections, and 0.6% triple infections. Significantly higher prevalences were found among the males, unmarried patients, those with lower education, institutionalized for more than 3 years, sent by social workers to the hospitals, with non-schizophrenic diseases, and with a higher degree of disability. However, only education, marriage, mode of hospitalization, and type of psychiatric disease were found to be significant determinants in a logistic regression model. The variation in prevalence related to demographic factors implies that nosocomial infections may not occur. The mode of hospitalization indicates that the patients may acquire the infections before hospitalization.

A boy with nosocomial malaria tropica contracted in a Dutch hospital

A 12-year-old Dutch boy was admitted because of severe neurotrauma after a traffic accident. On day 33 after admission, a Plasmodium falciparum infection was found in a routine blood smear. Most probably he was infected by blood of a patient next to him, a girl with severe malaria tropica. The genotype of the P. falciparum in both patients was identical.

[Diagnostic image (198). Four hospital employees with itch]

Four employees working on an Internal Medicine ward complained of itch after contact with an HIV-positive woman with crusted scabies.

Case of cryptic malaria

We report a case of falciparum malaria in a renal transplant patient with no history of foreign travel. Three weeks previously she had been a hospital inpatient with cellulitis and had stayed on the same ward as a man with falciparum malaria acquired in Nigeria. There were no cases of malaria in other patients on the ward at the same time. The parasites from the two cases were genotypically indistinguishable. Despite a thorough investigation, reviewed by an expert external panel, no clear route of infection between the cases was identified. Patients with malaria should be considered highly infectious by the parenteral route. They should be managed with the infection control precautions used for patients with bloodborne virus infections. Our case reinforces the need for high levels of compliance with universal infection control procedures.

Myiasis in Kuwait: nosocomial infections caused by lucilia sericata and Megaselia scalaris

Myiasis, the invasion of live human tissue by larvae of Diptera, is reported in the nasopharynx and a leg wound in two patients who were hospitalized for more than 72 hours in Mubarak Al-Kabeer Teaching Hospital in Kuwait City, Kuwait. On the fourth and fifth days after a 10-year-old Kuwaiti boy was admitted to the hospital intensive care unit in a bloodied and comatose state following a traffic accident, 'worms' that came out of his nostrils were fixed, cleared, and identified as second and third instar of Lucilia sericata (Diptera: Calliphoridae). After 14 days, 'worms' were seen in the original dressing of a 35-year-old Iranian man admitted to the Orthopedic Unit of the hospital with multiple lacerations and fractures. The larvae, in various stages of development, were identified as those of Megaselia scalaris (Diptera: Phoridae). Since the presence of larvae in both patients was recorded after a stay of at least 3-4 days in the hospital, by definition, these infestations are considered nosocomial.

Evaluation of coinfection with pinworms (Aspiculuris tetraptera, Dentostomella translucida, and Syphacia obvelata) in gerbils and mice

Mongolian gerbils (Meriones unguiculatus) naturally infected with the nematode Dentostomella translucida and mice (Mus musculus) that were either pinworm-free or harboring either or both Aspiculuris tetraptera and Syphacia abvelata were crossinfected experimentally with these nematode species. Gerbils were susceptible to infections by S. obvelata and A. tetraptera from mice, whereas mice were resistant to infection by D. translucida from gerbils. The data presented are the first regarding coinfections with these three pinworms in gerbils.

[Isolation of potencially pathogenic free-living amoebas in hospital dust]

OBJECTIVE

To evaluate the occurrence of free-living amoebas of the genera Acanthamoeba and Naegleria is dust samples colleted in two hospitals.

METHODS

One-hundred and thirty-two dust samples were collected in two hospitals in Brazil. Hospital collection sites were the following: intensive care unit, operation rooms, nursery, kitchen, emergency and infectious diseases isolation room. The isolation of the amoebas was performed in three culture media: non-nutrient agar inoculated with Escherichia coli, soy agar, and microculture in Giazzi-modified Pavlova's medium. The amoebas were identified according to morphological criteria.

RESULTS

Amoebas of the genera Acanthamoeba and Naegleria were found in 45.5% of the samples, of which 41.6% were collected in the university hospital and 50% in the state hospital. Of all, 45.5% were positive for the genera Acanthamoeba and 3.8% for genera Naegleria.

CONCLUSIONS

Potentially pathogenic free-living amoebas were seen in all sites of the two hospitals and Acanthamoeba was the most frequently isolated genera.

Inter-current and nosocomial infections among visceral leishmaniasis patients in Ethiopia: an observational study

From July 1989 up to September 1997, a total of 247 non-HIV associated visceral leishmaniasis (VL) patients were treated on outpatient basis in rural clinics (195 patients) and hospitalised in the Northern-Omo Regional Hospital (18 patients) and in Addis Ababa referral hospitals (34 patients). Patients treated in the rural clinics and in the Regional hospital originated from the same endemic area and had comparable baseline characteristics. Overall rates of complications (inter-current/concurrent infectious or non-infectious diseases or deaths) in the three categories were 10.7, 38.9 and 61.6%, while case fatality rates were 2.5, 5.6 and 11.7%, respectively. Nosocomial bacterial infections occurred in 16.6% of patients treated in the Regional hospital and 32.3% of patients treated in Addis Ababa referral hospitals, and these infections accounted for 42.8 and 52.4% of the complications seen in the respective categories. Among VL patients originating from the same endemic place and with comparable baseline clinical data, patients treated hospitalised had significantly higher rates of complications than patients treated on outpatient basis (P<0.001). Patients who had complications during the course of VL therapy had significantly lower pre-treatment haemoglobin levels. Considering the extra cost of hospitalisation and risk of nosocomial infections and petavalent antimonial therapy being fairly safe, we recommend that VL patients, unless with serious complications, should preferably be treated on ambulatory basis with follow-up to monitor response and inter-current infections if any.

Nosocomial submandibular infections with dipterous fly larvae

In September 1998, a case of nosocomial cutaneous myiasis caused by Lucilia sericata (Meigen, 1826) in a 77-year-old male was found. The patient had been receiving partial maxillectomy due to the presence of malignant tumor on premaxilla. This is the first verified case involving Lucilia sericata in Taegu, Korea. In the present paper, the salient morphological features of the third instar larvae involved have been studied.

Rational protocols for testing faeces in the investigation of sporadic hospital-acquired diarrhoea

Many recent studies have demonstrated that routine examination of faeces for conventional enteric pathogens such as salmonella, shigella, campylobacter and parasites in patients who develop sporadic hospital-acquired diarrhoea is unnecessary and wasteful. In this paper the advantages and disadvantages of a restricted testing protocol in patients with hospital-acquired diarrhoea are reviewed. Practical issues for safe implementation of such a protocol are also discussed.

Hospital-acquired malaria transmitted by contaminated gloves

We describe two cases of malaria occurring in a malaria-free zone in two in-patients, two weeks after a case of Plasmodium falciparum malaria, acquired in Burkina Faso, had been admitted to the same ward. After reviewing the techniques used by nursing staff, we conclude that transmission probably occurred via gloves contaminated following manipulation of venous cannulae and drip lines of the patient with Burkina Faso-acquired malaria and which had not been discarded before manipulating the intravenous lines of the other two patients. Nosocomial transmission of unusual and potentially life-threatening infections should be taken into consideration in those settings where compliance with universal precautions is not rigorous.

Experimental cross-infections of Haemonchus placei (Place, 1893) in sheep and cattle

To examine effects on biology and morphology, Haemonchus placei infections were propagated in cattle or sheep and infective larvae were introduced into the same or opposite host. Ovine source larvae had a geometric mean (GM) prepatent period of 26.5 days regardless of host species, compared to 30.6 days for bovine source larvae regardless of host species. Similarly, ovine source H. placei had a higher GM percentage establishment versus bovine source larvae (9.6% versus 3.4%) regardless of host species. The patent daily egg count for ovine source versus bovine source H. placei was 109.1 versus 50.0 FEC regardless of host species. Mean spicule length for ovine source H. placei was 492.5 microm while bovine source measured 496.5 microm. Mean female tail length for ovine source H. placei was 586.5 and 589.5 microm for bovine source H. placei. Using synlophe morphology, all worms that were measured were identified as H. placei. Sixty-three percent of females examined for vulvar flap morphology had knob-like vulvar flaps while the remaining 37% had linguiform vulvar flaps.

[Nosocomial diarrhea in adults due to microorganisms other than Clostridium difficile]

Nosocomial diarrhea of the adult is to the largest extend caused by Clostridium difficile. However, one must not underestimate the importance of other bacteria such as Salmonella or Shigella, which are most common in developing countries. Other viruses and parasites can equally be responsible for causing such infections.

Wound myiasis in urban and suburban United States

BACKGROUND

The epidemiologic characteristics of human myiasis in the United States remain undefined.

OBJECTIVE

To describe the most common clinical conditions associated with human myiasis and the causative maggot species.

METHODS

Multicenter, prospective observational study of urban and suburban patients who were infested with maggots.

RESULTS

Forty-two cases of US-acquired myiasis were collected from 20 participating centers. Most infestations occurred within preexisting wounds. No cases of tissue invasion were recorded. Host age averaged 60 years, with a male-female ratio of 5.5:1. Homelessness, alcoholism, and peripheral vascular disease were frequent cofactors. Two patients (5%) were hospitalized at the time of their infestation. The most common species was Phaenicia sericata (green blowfly; family: Calliphoridae). Other blowflies, flesh flies (Sarcophagidae), and humpbacked flies (Phoridae) also were identified. In 6 cases, 2 coinfesting species were identified.

CONCLUSIONS

Results of this prospective study of myiasis differ significantly from those of our analysis of previously published reports and suggest that most cases of human myiasis are caused by noninvasive blowflies laying eggs in preexisting wounds. Five percent of infestations were nosocomially acquired and not necessarily associated with patient neglect.

Outbreak of scabies in Norwegian nursing homes and home care patients: control and prevention

Over a period of five months (October 1998-February 1999), an outbreak of scabies affected 19 persons associated with a nursing home in Oslo, Norway. Scabies was diagnosed in 13 patients; six long-term patients, five short-term patients also cared for at home, and two home care patients associated with the same institution. Six healthcare workers who had assisted with infected patients in their own homes were also diagnosed with scabies. Two separate index cases were found. Both had had pruritus for several months, diagnosed as eczema, and were repeatedly treated at dermatology outpatient clinics before the diagnosis was made. Both index cases were cared for at home and in the nursing home (short-term). Repeated treatments with permethrin were tried before effective treatment with benzyl benzoate. Altogether 370 persons (patients, staff, relatives) were treated. In June-July 1999, scabies was diagnosed in two other nursing homes; six patients or staff, and 156 persons were treated. Patients with scabies were contact isolated and disinfection and cleaning was performed. Simultaneous treatment and washing or disinfection of clothing, bedding and environment of all potentially affected individuals is imperative to control an outbreak of scabies.

Nosocomial malaria from contamination of a multidose heparin container with blood

A girl developed Plasmodium falciparum malaria in Riyadh, Saudi Arabia, a non-malarious area. Twelve to 18 days before onset, she had been hospitalized for asthma on the same ward as three malaria patients. The only link between the malaria patients and the asthma patient was a multidose heparin container used to fill syringes for use on heparin locks and intravenous devices. Contamination of the heparin with blood occurred on at least one occasion when a needle had been left in place through the septum of this container and was used to refill a used syringe.

Study of Cyclospora cayetanensis in health care facilities, sewage water and green leafy vegetables in Nepal

Cyclospora cayetanensis, a newly emerging parasite, is endemic in Nepal. A total of 2,123 stool specimens were collected from 3 health care facilities based on clinical symptoms during the period between 1995 to October, 1998. Out of these specimens, cayetanensis oocysts were found in 632 (29.8%). To identify possible sources for Cyclospora infection, drinking water, sewage water, green-leafy vegetables including fecal samples of various animals were collected and examined. The vegetable leaves were washed in distilled water then the washings, sewage water and drinking water were centrifuged and the sediment were examined microscopically. As a result, oocyst of Cyclospora were identified in sewage water and vegetable washings on four different occasions in June, August, October and November. The positive results were also confirmed as C. cayetanensis by development of 2 sporocysts after 2 week incubation period in potassium dichromate. A survey of 196 domestic animals from the same areas demonstrated that two chickens were positive for Cyclospora-like organism and others were negative. Although further studies are needed to clarify the direct link between Cyclospora infection and these sources, the results suggest that sewage water, green leafy vegetables are possible sources of infection and chickens could be possible reservoir host of Cyclospora in Nepal.

Exposure workups

Exposure workups are an important responsibility for infection control personnel. A well-designed plan for investigating exposures, which includes appropriate algorithms, will enable infection control personnel to evaluate exposures rapidly and consistently so that nosocomial transmission is minimized. Infection control personnel should use their own data to develop policies and procedures that suit the needs of their facility. After they have implemented the plan, infection control personnel should continue to collect data on exposures so they can continuously improve their performance.

Epidemiologic features of intestinal parasitic infections in Italian mental institutions

To determine the prevalence of intestinal parasitic infections in the residents of four Italian psychiatric institutions, we examined the stool specimens collected in triplicate from 238 residents, enrolled between May 1995 and May 1996. Besides, physician and staff nurses provided data about each resident by standardized questionnaires. Parasites were detected in the fecal samples from 128 patients (53.8%). However, in the stool specimens from 106 residents only non-pathogenic protozoa were found (82.8%). Trichuris trichiura ova, Giardia lamblia cysts and trophozoites, Cryptosporidium parvum oocysts, and Balantidium coli cysts were found in the fecal samples from 22 residents (9.2%). B. hominis was the most prevalent parasite. It was detected in the fecal specimens from 97 residents (40.8%). The so-called nonpathogenic amebae were detected in the fecal specimens from 65 residents, though, at the same time, there was no evidence of Entamoeba histolytica infection. Twelve residents (5.0%) showed intestinal colonization by nonpathogenic flagellates. All the subjects with T. trichiura infection were housed in the facility of Ancona. Parasites were found in fecal samples from all the 11 residents with behavioural aberrations, but only three of those suffering from intestinal pathogen infection associated to diarrhea. Statistical analyses revealed that the presence of pathogenic parasites in fecal specimens was significantly associated with diarrhea, nausea, vomiting, abdominal pain, fever, behavioural aberrations and nonpathogenic protozoa (p < 0.01), but did not demonstrate any other significant associations between these parasites and the other variables, such as pruritus, mucus or blood in the stools and presence of fecal leukocytes. On the other hand, the presence of nonpathogenic protozoa was significantly related to aberrations such as pica, geophagia, phytophagy, coprophagy, coprophilia and pathogenic parasites (p < 0.01). Data analyses revealed that both pathogenic and nonpathogenic parasites were significantly more common in institutionalized patients than in controls. The rare presence of clinical signs and symptoms in colonized patients represents an important public health problem, since the presence of asymptomatic carriers among residents with low hygienic conditions, raises concern of transmission of parasitic infections to professional staff and other residents. Since the eradication of parasitic colonization in residential facilities is hard to reach, an effective prevention is the only measure to deal with this public health problem.

Yield from stool testing of pediatric inpatients

OBJECTIVES

To quantify the yield from stool testing in pediatric inpatients and to identify criteria to test stool more deliberately without sacrificing diagnostic sensitivity.

DESIGN

A retrospective review was performed of all stool cultures, ova and parasite examinations, and Clostridium [correction of Clostridia] difficile toxin assays performed on pediatric inpatients, aged 3 days to 18 years, at Thomas Jefferson University Hospital, Philadelphia, Pa, for 1 year. Medical records were reviewed for positive cases, each with 2 controls matched for age and test type. For this study, the term admission refers to the interval between the times each patient was admitted to and discharged from the hospital. Some patients had multiple stool tests sent to the laboratory during a single admission; some patients had more than 1 admission during the study period. Statistical analysis was performed using X2 analysis and the Student 2-tailed t test with a commercially available statistical software package (Statworks, Cricket Software, Philadelphia).

RESULTS

Of 250 patient admissions to the hospital for which stool was cultured, 7 cultures (2.8%) were positive. Of 63 patient admissions having ova and parasite testing, 1 (2%) had a positive result. Clostridium [correction of Clostridia] difficile toxin assays were performed on 40 patient admissions to the hospital, and 7 (18%) had a positive result. Only 18 (3.0%) of 598 of all test results reviewed were positive. Costs of negative test results totaled $26,084. More patients (71%) with positive stool cultures than control patients (21%) had a temperature higher than or equal to 38 degrees C (X2, P < .05); however, relying on this sign missed 29% of the children with bacterial infection. A white blood cell band count of at least 0.10 was 100% sensitive and 79% specific in identifying patients with positive stool culture. There was no statistically significant relationship between stool culture results and age, total white blood cell count or white blood cell segmented neutrophil count, and no relationship between C. difficile toxin assay results and any of the above characteristics. Clostridium [correction of Clostridia] difficile was the most common pathogen identified (6 of 9) in patients developing gastrointestinal symptoms after admission; however, Salmonella enteritidis and Shigella sonnei were also significant causes (3 of 9).

CONCLUSIONS

There is low yield from stool testing of pediatric inpatients: C. difficile toxin assay has the highest yield. Clostridium [correction of Clostridia] difficile testing is most valuable for children with nosocomial gastrointestinal symptoms although other bacterial pathogens do cause nosocomial symptoms in children. More selective stool testing could help us be more efficient with our patient care resources.

The first reported outbreak of diarrheal illness associated with Cyclospora in the United States

OBJECTIVE

To investigate and characterize the epidemiology of a diarrheal outbreak associated with a potentially new pathogen, Cyclospora species (previously referred to as Cyanobacteria [blue-green algae]-like bodies).

DESIGN

Three retrospective cohort studies supported by laboratory studies, environmental investigation, and community surveillance.

SETTING

A hospital in Chicago.

PARTICIPANTS

Housestaff physicians and hospital administrative staff.

MEASUREMENTS

Identification of clinical features associated with illness and potential risks for acquisition of infection.

RESULTS

Illness was characterized by watery diarrhea, abdominal cramping, decreased appetite, and low-grade fever. Symptoms typically occurred in a distinctive cycle of remissions and exacerbations lasting up to several weeks. Stool cultures and examinations for known ova and parasites were negative. Microscopic examination of stool specimens from 11 ill persons showed many spherical bodies, 8 to 10 microns in diameter, that were identified as Cyclospora organisms. The organisms disappeared by 9 weeks after onset of illness in the 7 patients from whom follow-up specimens were obtained. Epidemiologic studies implicated tap water from a physicians' dormitory as the most likely source of the outbreak. Environmental investigation suggested that stagnant water in a storage tank may have contaminated the water supply after a pump failure.

CONCLUSIONS

This is the first reported outbreak of diarrhea associated with Cyclospora in the United States. Cyclospora may be a human enteric pathogen able to produce bouts of acute and relapsing diarrhea, and it should be considered in assessments of patients with unexplained, prolonged diarrheal illness.

Lucilia sericata (Diptera: Calliphoridae) causing hospital-acquired myiasis of a traumatic wound

A case of traumatic nosocomial myiasis caused by the green bottle fly Lucilia sericata (Meigen, 1826) occurred in a patient hospitalized following a serious road traffic accident. The patient had suffered extensive polytrauma particularly in the facial area of the skull. A total of 50 larvae was discovered in the oral cavity, nose, paranasal sinuses and enucleated eye-socket. Projected timing indicated that the eggs were laid while the patient was hospitalized. The development of myiasis was facilitated by the mental and physical debility and dependency of the patient, numerous and deep facial necrotic wounds and a lengthy period of hot weather which led to prolonged open window ventilation of his room.

Dermatologic manifestations of nosocomial infections

There is no substitute for preventing dermatologic infection in a hospitalized patient by maintaining intact, well nourished skin. The integrity of the integument becomes assaulted on a daily basis from a variety of methods. Measures to lessen this risk can be undertaken, but it may not be totally preventable. The phenomenon of infected desquamated squamous cells being dispersed into the environment by patients and health care workers is one that deserves further study. If this proves to be an important factor, hospital spread of bacteria may indeed be unavoidable. It is hoped that this review will serve as a starting point in an area short on clinical data. Further study into this arena is clearly needed.

Screening for intestinal parasites. Is a single specimen valid?

To assess the validity of a single stool or perianal swab specimen when screening for potentially pathogenic parasites, 88 residents of a centre for developmentally handicapped adults were screened by collecting on alternate days three stool samples and pinworm swabs. Both sensitivity and negative predictive values were so low that three samples were required for some parasites. The species being screened for and its underlying prevalence must be considered before collecting only one specimen to reduce laboratory costs.

[Incidence of Cryptosporidium sp in patients treated in a general hospital. Technics for the identification of oocysts in feces]

In feces referred for parasite investigation from 1973 patients of the Hospital Clinico Universitario in Salamanca, 27 instances of infestation by Cryptosporidium sp (1.5% of all investigated patients) were detected in 19 children (1.4%) and 8 adults (2.2%). The incidence in patients with antibodies against the human immunodeficiency virus (HIV) was 12.5%, in contrast with 1.25% in patients without anti-HIV antibodies. 55.5% of the instances of Cryptosporidium sp infestation were found in children less than 4 years old. The higher incidence was in winter and spring. The association with other enteropathogens was found in 14.8%. Diarrhea and abdominal pain were the most common clinical features of cryptosporidial disease. Chronic diarrhea was found in two adult patients with acquired immunodeficiency syndrome. In immunocompromised children and adults asymptomatic carriers were found. The sensitivity and specificity of immunofluorescence testing with monoclonal antibodies as compared with Ziehl-Neelsen stain for the detection of Cryptosporidium sp oocysts were 100%.

Enterobius vermicularis infection in a children's ward

Following the discovery that two patients on a children's orthopaedic ward were excreting Enterobius, all patients and staff on the ward were screened for the presence of pinworms. None of the staff was infected but 11 (55%) of 20 patients either had Enterobius ova on the anal margin or excreted worms following piperazine treatment. Epidemiological investigations indicated that this was unlikely to be a ward outbreak because four of the infected children had been on the ward for under 3 days, i.e., less than the prepatent period for Enterobius. Although none of the children was symptomatic, all children and staff on the ward were treated with piperazine. Faecal samples were collected from nine children and the majority of their worm load was shed within 32 h of starting therapy. Microscopic examination of the adult male worms showed that each patient was excreting both Enterobius vermicularis and E. gregorii.