Scabies: an itchy problem

Scabies-a small word that can, and often does, impart great anxiety and apprehension among health care workers (HCWs). Yet the epidemiology associated with this human parasitic infestation is well understood, as are the mechanisms for both its treatment and control.

[Animal mite-induced epizoonoses and their significance in dermatology]

Different mite species may infest humans temporarily; such arthropods should be considered a possible cause of pruritic skin reactions of unclear origin. Pseudo-scabies is a common problem. This self-limiting dermatosis may often be misdiagnosed. Several mite species including Sarcoptes scabiei var. canis, Sarcoptes scabiei var. bovis, Notoedres cati, Cheyletiella yasguri, Cheyletiella blakei, Dermanyssus gallinae and Ophionyssus natricis may infest human skin, causing symptoms. Other less common animal mites, Neotrombicula autumnalis and foodstuff mites are also discussed.

Atypical scabies in HIV-positive patients

Five cases of Norwegian or keratotic scabies in HIV-positive patients are described. One of these patients was the source of an outbreak in a hospital, ultimately involving 72 persons. Three of our patients had a markedly pruritic eruption. This is unusual in crusted scabies in which pruritus is usually slight or absent. Two of the five patients had unusual CD4 counts of more than 200 cells per cubic millimeter. All our patients responded to lindane and keratolytic agents. When generalized papular, crusted, or eczematoid lesions are observed in HIV-positive patients, particularly if the CD4 count is less than 200/mm3, scabies should be included in the differential diagnosis.

Crusted ("Norwegian") scabies in a specialist HIV unit: successful use of ivermectin and failure to prevent nosocomial transmission

A nosocomial outbreak of scabies in a specialist inpatient HIV unit resulted from a patient admitted with crusted scabies. Treatment of his infestation with topical scabicides alone failed and he remained infectious for several weeks. His infestation was then eradicated with combined topical treatment and oral ivermectin. In total, 14 (88%) out of 19 ward staff became symptomatic, and 4 (21%) had evidence of scabies on potassium hydroxide examination of skin scrapings. The ward infection control policy was changed to distinguish patients with crusted scabies from those with ordinary scabies. A second patient with crusted scabies was treated with combined oral and topical therapy early in his admission and nursed with more stringent isolation procedures. No nosocomial transmission occurred and his infestation responded rapidly to treatment. Patients with crusted scabies require strict barrier nursing if nosocomial transmission is to be avoided. Ivermectin combined with topical scabicides may be a more efficacious treatment than topical scabicides alone in such patients.

Management of chronic, resistive scabies: a case study

It took about 9 months of diligent effort to resolve Mr. C's chronic, highly resistive case of scabies. In all, Mr. C. had a total of seven treatments with a scabicidal lotion or cream. In addition, other medications were prescribed in an attempt to resolve his skin condition. The treatment of scabies is costly to an institution, in medications, supplies, and additional nursing time required to treat the patient, as well as other patients prophylactically. Therefore it behooves nurses to do a thorough skin assessment on all nursing home care patients at least monthly, recognize early signs of scabies, and be cognizant of the fact that scabies in the elderly patient may have an atypical distribution.

An outbreak of Norwegian scabies in a surgical ward

An outbreak of Norwegian scabies in a surgical ward of a teaching hospital was reported. The source of infestation was an elderly diabetic. The epidemic involved 28 of 32 medical personnel in the ward and 3 family contacts. All infected individuals were given a two-course treatment with hexachlorcyclohexane gel. Control of the outbreak was achieved by strict handwashing after patient contact, application of gowns and gloves for contact with skin lesions and the treatment of infected persons. Norwegian scabies in institutions is on the rise, vigilance for its occurrence is needed.

Transmission of Sarcoptes scabiei from animal to man and its control

Outbreak of Sarcoptes scabiei in animals spilling over to man in close association was observed in two adjacent villages, Fewgram and Nurpur in the district of Birbhum, West Bengal, from mid-November to mid-December, 1991. Nineteen goats and one calf who did not receive any treatment died of sarcoptic manage. All infected animals got cured with external application of deltamethrin, a synthetic pyrethroid and triazapentadiene. Human cases were treated successfully with benzene hexachloride (2%).

Crusted scabies in pregnancy

An otherwise healthy 19-year-old pregnant woman developed crusted scabies. She and her husband had previously been treated for scabies. In spite of appropriate treatment both suffered several relapses, and later their infant was also affected. Ultimately, the infection was eradicated. As far as we are aware, this is the first recorded case of crusted scabies occurring in a healthy pregnant woman.

Ectoparasites as sexually transmitted diseases

Although Sarcoptes scabii and Phthirus pubis infestations in humans are not always associated with the presence of other sexually transmitted diseases, usually they are. Therefore, patients presenting with scabies or P. pubis should be routinely tested for various sexually transmitted diseases. These very uncomfortable infestations are easily curable with proper therapy. Lindane 1% preparations effectively exterminate both vermin. We have not seen any resistant strains. Especially with P. pubis, all household contacts should be treated to avoid reinfestation.

[Clinical study of scabies. The changes in the modes of transmission, and its diagnosis and treatment]

Scabies has become a common disease, not sexually transmitted but transmitted in households. Although it is also known to cause an epidemic in hospitals for the aged patients or residential homes, no effective treatment was taken for it at the present time. From January 1985 to December 1992, 424 patients with scabies (249 males and 175 females) visited the Dermatological clinic of Nippon Medical School Main Hospital. In these cases, only 13 patients (3.1%) were recognized as having STD. The sources of infestation were unclear in most cases where the disease was transmitted in households, which account for 38.5% of the patients. In 68 cases (16.0%), outbreaks of scabies in hospitals and residential homes affected the patients as well as the staffs and their families. The number of scabies cases which were infested in hospitals is increasing yearly. It is speculated that the hospitals for the aged patients and residential homes are becoming the main source of scabietic infestation. Only 16.6% of the patients were previously diagnosed or suspected to have scabies by their family doctors. It seems that the diagnosis of scabies is extremely difficult for the general practitioner. A considerable number of the patients who had been diagnosed or suspected to have scabies changed their doctor or stop visiting them. This is because an appropriate treatment is not available in most of medical facilities. At the time of the first visit to our clinic, 93.6% of the patients was diagnosed or suspected to have scabies, and the mite was demonstrated in 63.2% of the patients. It is suggested that careful inspection of scabietic burrows and the skillful technique to demonstrate the mite are essential to establish the diagnosis of scabies. Atopic dermatitis was the most common diagnosis of the patients who were misdiagnosed at the first time and later turned out to have scabies. These patients did have atopic dermatitis besides scabies. After the treatment with benzyl benzoate with crotamiton, 70.3% of the patients were cured and up to 94.9% of the patients were over improved. We compared the therapeutic effect of phenothrin to that of benzyl benzoate. Benzyl benzoate had more antipruritic effect and a little more improvement of skin lesion than phenothrin. However, there was no significant difference between benzyl benzoate and phenothrin in the period of time until the skin lesion cleared. Phenothrin is considered to have an adequate therapeutic effect for scabies.

Human scabies acquired from a pet puppy

Scabies is a very old contagious skin disease caused by itch mite, Sarcoptes scabiei which burrows into the stratum corneum. Nowadays, human scabies is one of the health problems among the school children. This paper dealt with a case of scabies in a preschool aged child who acquired the infestation from his pet puppy.

Scabies epidemic: price and prejudice

Scabies epidemics are not unusual, and the recommended way of stopping them is by simultaneous treatment of everybody in the facility; this has been known since the last century, when Norwegian scabies was a problem in Norway. When this is not done, scabies epidemics can smolder for months. Scabies should not spread with good infection control measures, but we learned that a good infection control service is not enough. Efforts have to be done to educate everybody in the hospital, including laundry workers, and to improve work conditions.

Knowledge, attitudes and practices (KAP) of human intestinal helminths (worms) in two rural communities in Nyanza Province, Western Kenya

Six common health problems prevalent in two rural communities-Buoye and Kanyawegi Sublocations--of Kisumu District, in Western Kenya, were selected and the knowledge, attitudes and practices (KAP) of the communities investigated with special reference to human intestinal helminths (worms). The selected diseases were malaria, diarrhoea, human intestinal helminths, scabies, schistosomiasis, and measles. The selection of the six health problems was based on a previous more general KAP study of health and disease at household level in the two areas and information from the Medical Officer of Health in the area. The specific objective was to assess the perceived importance of intestinal worms vis-a-vis other common and known health problems in the community. The study included an analysis of responses to questions on human intestinal worms broken down by sex, age and education level of respondents as well as identification and perceived health effects of a set of vectors and parasites of common diseases in the area. Compared with the other five health problems, intestinal worms did not rank highly in people's minds as an important health problem, although very high proportions of respondents knew of the problem, notably the young and educated. This high proportion of respondents who knew of the problem could describe the symptoms with some accuracy and could correctly identify the vectors and parasite samples. But the full implications of intestinal worms were not fully appreciated. Both communities reflected relatively poor comprehension of causes, treatment and methods of prevention.(ABSTRACT TRUNCATED AT 250 WORDS)

Scabies research: another dimension

The life cycle of canine scabies has been studied extensively. Currently studies are focusing on mite behavior, physiological requirements, host specificity, mite survival, and clinical complications of scabies. Investigations are giving insight into immunologic responses to infestation and cross-reactivity with house dust mites. A diagnostic blood test or vaccine may become a future reality, if a unique antibody response can be isolated. Can scabies transmit the human immunodeficiency virus (HIV)? This controversial area needs prompt definitive exploration.

Scabies in AIDS

Human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) will be the most common disease triggering crusted (Norwegian) scabies. Scabies should be suspected in any atypical itching (or non) rash in HIV/AIDS patients. Attempt to prove the diagnosis by doing a skin scraping, or if negative, a skin biopsy. Unusual forms of scabies in HIV/AIDS can be divided into crusted scabies and atypical (exaggerated) scabies. Therapy requires the sequential use of scabicides, usually over a longer period than is required to clear an ordinary case of scabies. Compliance is a concern, and the scabicides are best administered under supervision whenever possible. Isolating the index patient and treating the environment of patients with crusted or atypical scabies is much more significant than in ordinary scabies. The transmission in hospitals of ordinary scabies from an index patient with crusted scabies to other patients, health care workers, etc, is common. Protective measures and early diagnosis and therapy are essential.

Scabies

Scabies is highly contagious and is usually transmitted by direct personal contact. It typically presents as an intensely pruritic eruption. Atypical presentations are common in Norwegian scabies and in childhood scabies. Infestation is documented by visualizing the mite, its eggs or scybala on low-power microscopy. The treatment of choice is 5 percent permethrin cream, used in a single application at bedtime and removed the next morning.

[The parasite-host specificity of the itch mite Sarcoptes scabiei (Acariformes: Sarcoptidae) in man and animals (a review of the literature)]

The primary parasitic relations between the itch mite Sarcoptes scabiei (L.) and man are confirmed indirectly by the presence in the family Sarcoptidae of close genera, members of which parasitize primates. Judging from the composition of domestic and wild animals-hosts, the source of their infection with S. scabiei was man that gave rise to numerous forms of mites specific to individual species of hosts or their related groups belonging to different taxonomic ranks. Three types of host relations and, accordingly, forms of sarcoptosis are suggested at the infection from an alien host: pseudosarcoptosis, temporary self-curable and typical lingering sarcoptosis. The ways of reinfection, invasiveness of stages of the mite and clinical picture for each form of the disease are analyzed.

Nosocomial outbreak of scabies

Scabies is a common infestation caused by the human itch mite Sarcoptes scabiei. Small outbreaks in communities or hospitals are not uncommon, but are rarely documented. In this paper, we report on a nosocomial outbreak of scabies originating from a patient with Norwegian scabies at the Intensive Care Unit in Taiwan Provincial Tainan Hospital. Twenty-nine individuals including four inpatients and 25 hospital personnel were involved. The diagnosis was based on history, clinical findings or a positive skin scraping. Unfamiliarity with the clinical manifestations delayed the diagnosis and the highly contagious nature of Norwegian scabies precipitated this outbreak. Early initiation of effective control measures with extensive therapeutic and prophylactic treatment of all contacts resulted in successful eradication of the outbreak.

Scabies and Pyoderma in Lilongwe, Malawi. Prevalence and seasonal fluctuation

From January 1988 to June 1989, data were collected daily on the patients who were seen at the Dermatology Clinic attached to the Kamuzu Central Hospital, Lilongwe, Malawi. Cases were diagnosed and patients were treated under the supervision of a dermatologist. A total of 34,002 patients were seen during the study period. Of these patients, 15,526 (45.7%) were children and 18,476 (54.3%) were adults. The prevalence of scabies was 40.4% in children and 31.6% in adults, whereas the prevalence of impetigo/bacterial skin infections was 26% in children and 10.4% in adults. Based on data accumulated for periods of 1 month, the incidence rate of scabies was highest during the cold, dry season (May-November) and the incidence rate of skin infection was highest during the hot, rainy season (December-April). Since the patients who were studied lived predominantly in rural settings, an explanation for the higher incidence rate of scabies during the cold season could be close body contact resulting from the overcrowding within the houses. The reason for the increase in the incidence rate of pyoderma during the rainy season might be linked to deficiencies in hygienic precautions. A community-based intervention strategy with children as its target population is proposed to combat these diseases.

[Hospital spread of scabies from an immunocompromised patient with Norwegian scabies]

Scabies was first found in a 71-year-old female who had been diagnosed as having leukemic transformation of primary myelofibrosis and had undergone treatment for the disease. She was admitted to the hospital in December 1986, because of abdominal fullness and a generalized subcutaneous tumor that proved to be myeloblastoma. For treatment of the underlying disease, the regimen of the combination of vindesine, cyclophosphamide, 6-mercaptopurine, and prednisolone was selected. She developed cardiac failure and fell into a coma one month after starting the anticancer therapy. She was put on artificial respiration and on additional steroid therapy as well. Dexamethasone was administrated at 16 mg/day. Since the myeloblastomas found on admission regressed, the steroid therapy was continued. She was in coma for a few days before her skin lesions turned red and formed a grayish crust in the lower abdominal region. Several days later, the doctor responsible for the treatment of this patient developed pruritus and exanthema on both arms, and soon many nurses in the same hospital-ward developed similar symptoms. At approximately the same time, the patient with myelofibrosis was diagnosed as having Norwegian scabies: the crusted skin lesions revealing many Sarcoptes scabiei mites. Two doctors (2/18), 17 nurses (17/19) and 3 other patients (3/51) were found to have contracted scabies, and we recognized the hospital spread of the infection. The first patient was isolated in a private room, and we avoided direct contact with her. The persons with scabies were treated with crotamiton liniment. The first scabies patient died of cardiac failure 1 month after falling into a coma.(ABSTRACT TRUNCATED AT 250 WORDS)

[Canine scabies in man]

Parasitic prurigo caused by scabies mites from recently acquired puppies is described in two patients and their family members. Because Sarcoptes scabiei var. canis (dog) occasionally survives in man, patients with persisting complaints despite treatment of their dogs should be treated with the topical scabicide lindane for one night.

Scabies in nursing homes: an eradication program with permethrin 5% cream

Permethrin 5% cream was used to treat scabies in three large nursing homes under a compassionate-plea protocol for chronic, therapy-resistant infestations. All residents, staff, and frequent visitors were treated whether or not symptomatic. Family members of these groups were treated either when symptomatic or directly exposed to scabies. Nine hundred ninety-five persons were treated, 202 of whom were diagnosed with scabies. Approximately 35% (111 of 313) of nursing home residents were diagnosed with scabies. These were patients in whom multiple treatments with other scabicides were unsuccessful. At the completion of the study, 195 patients were examined for efficacy of treatment. Of these, 91 (46.7%) had clearing of lesions with one medication application, 77 (39.5%) with two treatments, and 23 (11.8%) with three or more treatments. The overall cure rate was 98%. Adverse experiences occurred in 2.4% of cases and were mild (i.e., pruritus and rash).

The "nuisance" sexually transmitted diseases: molluscum contagiosum, scabies, and crab lice

Although molluscum contagiosum, scabies, and infestation by crab lice do not carry the requirements of partner notification or other long-term consequences, they are among the most commonly reported sexually transmitted disease. Molluscum contagiosum is a benign viral infection of the skin epidermal layer, most often transmitted by intimate skin-to-skin contact. The lesions often resolve spontaneously over time, but patient discomfort or social reasons may require destructive removal of the lesions. Scabies is caused by the Sarcoptes scabiei mite. The victims continually itch, especially at night, and often seek over-the-counter topical remedies before seeing a clinician. Once a correct diagnosis is made, successful resolution of this disease and its itching can be achieved. Head and pubic lice account for most of the more than three million cases of louse infestation treated in the United States each year. Symptoms of infestation generally include itching that leads to scratching, erythema, irritation, and inflammation. A careful diagnosis followed by disinfection, symptomatic treatment, and psychologic support should result in a complete cure with no long-term effects.

Effects of sarcoptic mange on lactating swine and growing pigs

The impact of Sarcoptic mange on sows and on performance of their offspring from birth to slaughter was determined. Sows naturally infested with Sarcoptic mange were paired, mated to the same boar, and assigned randomly to treated or control farrowing groups. Treated sows received ivermectin s.c. at 300 micrograms/kg body weight; control sows received the vehicle s.c. Sow performance was evaluated via sow feed consumption, litter size, litter birth weights, litter weaning weights and piglet death loss from birth to weaning. Seven replicates (farrowing groups), each with six sow pairs, were included in the trial. Offspring from treated and control sows, 35 head/group, were fed to slaughter weights. Untreated sows had litters that weighed 4.14 kg less than ivermectin-treated sow litters at 21 d (P less than .07). Treated sows consumed 1.95 kg less feed per weaned piglet and .13 kg less feed per kilogram of weaned piglet (P less than .05). Piglets from treated sows were 5.79 kg/head heavier at slaughter (P less than .05) and had a .05 kg/d superior average daily gain (P less than .05).

Pig handler's itch

Forty-six humans who contacted pigs infested with Sarcoptes scabiei were investigated. Thirty (65.2%) had symptoms of sarcoptes scabies, and S. scabiei mites could be recovered from 20 (66.6%) skin scrapings. Itching was the main symptom. People within the age group of 26-35 years were infested the most. Hands and legs were the most common sites of the lesions, which subsided within 2-3 weeks when the infested pigs were treated and the intimate contact with the pigs was prevented.

Epidemic Norwegian scabies in a geriatric unit

Norwegian scabies is highly contagious and presents with a psoriasiform dermatosis. It afflicts particularly the elderly and patients with immunosuppression. Two weeks after the admission of an index case of Norwegian scabies to a geriatric ward, 13 and 25 patients and 6 of 18 ward nurses developed scabies. Despite comprehensive treatment, the ward epidemic recurred 6 weeks later probably as a result of inadequate treatment of the index case. This diagnosis should be considered when patients from high-risk groups present with an undiagnosed rash.

Norwegian scabies in an infant with acquired immunodeficiency syndrome

A 6-month-old infant with acquired immunodeficiency syndrome (AIDS) and typical scabies subsequently developed Norwegian scabies, with deterioration of clinical status. The infestation spread to several health care workers who were in close contact with the patient, despite standard isolation precautions. In the rapidly growing hospitalized pediatric AIDS population, Norwegian scabies should be considered in the differential diagnosis of eczematous or seborrheic dermatitis.

Prevalence of Sarcoptes scabiei in the homes and nursing homes of scabietic patients

This study determined the prevalence of Sarcoptes scabiei in the home environment of 37 confirmed cases of scabies and in five nursing homes with scabietic patients. Dust samples from 44% of infested patients' homes contained scabies mites. Live mites at the time the dust samples were analyzed were present in 64% of these homes. Live mites were recovered most often from bedroom floors or overstuffed chairs and couches. The density of live and dead mites ranged from 1 to 5 mites/0.1 gm of dust or 1 to 9 mites/m2 of surface area sampled. The presence of mites in fomites coupled with survival and host-seeking behavior indicate that it is possible for a person to become infested by dislodged mites in contaminated home, school, and work environments. By contrast, only a small number of mites were recovered from beds, furniture, and floors of scabies-infested nursing homes. Mite-contaminated fomites may be less important in the transmission of scabies in nursing homes than in private homes.

[Childhood scabies: a different entity]

Epidemiological, clinical, diagnostic and therapeutic aspects that make scabies a clinical entity with a special personality in the pediatric field, are reviewed. On the epidemiological aspects, a special mention of its unsuspected frequency in this age is made. Scabies is an endemic disease in our country among the more deprived people. On the clinical aspects, the great importance of clinical history and distribution of skin lesions for the early diagnosis is pointed out. Some "alert pointers" are described for this early diagnosis. On the therapeutic field, the importance of the primary care prevention is discussed, and the drug approach for its relieve is commented.

Experimental transmission of a goat strain of Sarcoptes scabiei to desert sheep and its treatment with ivermectin

Desert sheep were experimentally infected with a goat strain of Sarcoptes scabiei, proving that this mite is not completely host specific. More severe lesions were produced on sheep when the mites were applied to lacerated than when applied to scarified or non-scarified areas. Lesions were more pronounced on moistened areas than dry areas and lesions produced on dry scarified areas resembled those produced on non-scarified moistened ones. Skin scrapings from the experimental lesions in the sheep contained numerous mites of all stages, proving the goat mites had become well established and were reproducing actively in the experimental lesions. Severe histopathological changes were observed in skin sections, comprising mainly thick crust formation, mites beneath the keratin and severe degenerative and necrotic changes. Treatment of sheep with ivermectin at a dose rate of 200 micrograms kg-1 body weight produced rapid and excellent cure.

An outbreak of scabies among employees in a hospital-associated commercial laundry

The acquisition of scabies in either the community or the health care setting is not uncommon, although it is infrequently documented. In Missouri, individual cases of scabies infestation are not reportable, but outbreak notification is required. Outside of the nursing home environment, where three to six outbreaks of scabies per year require assistance from the nosocomial disease subprogram of the Kansas City Health Department, only two other outbreaks have been recorded in the community since August 1977. One involved a school with 93 cases and the other a commercial laundry, which is reported here. The latter outbreak illustrates the difficulty encountered when attempting to classify an outbreak as either nosocomially acquired or community-acquired.

[Facial involvement in scabies in infancy]

The infestation of a 3-month-old child with Sarcoptes scabiei by way of infested nipples during the breast-feeding period led initially to facial papules and later to generalized dermatitis. Scabies mites were not detected on the face; studies on ten infested babies in India supported this findings. Thus, direct antiscabies treatment to the face is not necessary in babies.

[Scabies in an adopted infant from Brazil]

The adoption of babies from third-world countries with endemic scabies by European and North American families is an ever increasing phenomenon. A brazilian baby was presented with papulopustules on both cheeks and an itchy, papular rash that developed four weeks upon arrival in Germany. Meanwhile the adoptive mother had contracted scabies.

Zoonotic dermatoses of dogs and cats

Zoonotic dermatoses in dogs and cats are an important cause of skin disease in human beings. In addition, human dermatoses may occasionally be transmitted to dogs and cats. The veterinarian and the physician form a critical "health care team" in the proper management of these disorders.