Field trial of 1% niclosamide as a topical antipenetrant to Schistosoma mansoni cercariae.

A randomized, double-blind, placebo-controlled field trial of a topical antipenetrant lotion, 1% niclosamide, applied daily to the upper and lower limbs of farmers occupationally exposed to Schistosoma mansoni cercarial-infested water, was conducted in the Nile Delta to assess its safety and efficacy in preventing reinfection. Farmers aged 18-40 years were treated to cure their S. mansoni infections three months prior to the onset of the trial. Subjects were randomly assigned to receive niclosamide or placebo lotion that was self-applied daily for five months. A total of 186 subjects met the inclusion criteria and completed the trial. The exposure to schistosomal-infested water occurred during routine irrigation activities from June to November 1991. Stool specimens were evaluated monthly during and for two months following the lotion application period. The subjects applying the niclosamide lotion were comparable to those applying placebo lotion in age (mean 30 years for both), total water contact (184.5 hr versus 173.8 hr), reported lotion application compliance (88% versus 92%), and reported water contact involving skin exposure other than upper and lower limbs (23% versus 27%). The schistosomal reinfection rate was lower in the niclosamide group (53.3%) compared with the placebo lotion group (71.3%), (P < 0.02). Increased protection might be obtained with total body application for shorter, less intense, water contact exposures.

Evaluation of a twice-a-week application of 1% niclosamide lotion in preventing Schistosoma haematobium reinfection.

A randomized double-blind trial was conducted to assess the efficacy of a twice-a-week application of 1% niclosamide lotion for prevention of Schistosoma haematobium reinfection. Six hundred farmers in Fayoum, Egypt, 18-40 years of age, were treated to cure their S. haematobium infection, then randomly assigned to self-apply niclosamide or placebo lotion to their limbs, neck, and torso. Subjects were exposed to schistosomal-infested water during routine irrigation activities from April to October 1992. Three hundred fifty subjects met the inclusion criteria and completed the trial, 169 (48.3%) in the niclosamide group and 181 (51.7%) in the placebo group. The subjects assigned to the niclosamide-treated group were comparable with those in the placebo group in age (27.2 versus 27.8 years), total water contact (101.9 versus 109.0 hr), lotion application compliance (93.5% versus 90.6%), and avoidance of whole body water contact (94.7% versus 96.7%). The reinfection rate with S. haematobium was 30.8% in the niclosamide-treated group and 28.2% in the placebo group. Niclosamide lotion applied to the limbs and trunk twice a week failed to prevent S. haematobium reinfection.

Etiology of acute diarrhea among United States Embassy personnel and dependents in Cairo, Egypt.

The purpose of this study was to identify the enteropathogens causing acute diarrheal disease in Americans living in the North Africa/Middle East region during a 34-month period from February 12, 1985 to December 30, 1987 to guide preventive and therapeutic measures. Stool specimens were examined and an epidemiologic questionnaire was administered to patients with acute diarrhea at the Outpatient Health Unit of the United States Embassy in Cairo, Egypt. The subjects consisted of 126 American employees and dependents of the U. S. Embassy in Cairo, Egypt with diarrhea of less than two-weeks duration. Subjects received routine medical care administered by the U.S. Embassy Medical staff. A possible etiologic agent was detected in 41% of the subjects. Enteroadherent Escherichia coli was the most commonly isolated enteropathogen. A high degree of antimicrobial resistance was noted among the bacterial isolates, but all were susceptible to the quinolone antibiotics. Episodes of acute diarrhea occurring among American expatriates in Cairo, Egypt were primarily of bacterial etiology, but only a small portion were caused by the bacterial pathogens routinely identified in a standard clinical bacteriology laboratory. Most of the diarrheal episodes were due to noninvasive enteroadherent E. coli that may cause prolonged disease requiring antimicrobial therapy.

The rapid diagnosis of infectious mononucleosis using an ELISA that detects IgM antibody to a peptide component of Epstein-Barr virus nuclear antigen.

An enzyme-linked immunosorbent assay (ELISA) that detects IgM antibody to a peptide component of the Epstein-Barr virus (EBV) nuclear antigen (EBNA-1) was compared with a conventional rapid heterophil antibody method for the rapid diagnosis of infectious mononucleosis. Discrepancies between the two methods were further analyzed using an indirect immunofluorescence assay to detect antibodies to EBV antigens. We evaluated 298 cases of suspected infectious mononucleosis. The ELISA was very sensitive (98.7%) and able to detect some cases (seven (9%) of 75 confirmed positives) that were negative by the rapid heterophil antibody test, but confirmed by immunofluorescence. However, approximately 17% of all positive tests could not be confirmed by EBV-specific immunofluorescence; thus, the overall positive predictive value was 83%; negative predictive value was 99.5%; and specificity was 93%. The high rate of false-positive tests makes this rapid ELISA unsuitable for the diagnosis of infectious mononucleosis.

Aztreonam compared to chloramphenicol in the treatment of enteric fevers.

Fifty-seven patients, twenty-six males and thirty-one females, aged 6 to 50 years (mean 12.6 years) with proven Salmonella typhi or S. paratyphi A septicaemia, were treated in an open randomized parallel study with either aztreonam or chloramphenicol. Aztreonam was given intramuscularly at a level of 50 to 80 mg/kg body weight per dose every 8 h for 7 days to thirty patients. Chloramphenicol was given orally in a dose of 50 to 70 mg/kg body weight every 6 h for 12 days to twenty-seven patients. All patients responded rapidly to treatment, becoming afebrile and asymptomatic within 5.5 to 6.4 days. Only one patient on aztreonam relapsed following treatment, whereas three patients relapsed after chloramphenicol treatment. There were no serious side effects with either drug.

Cefixime in the treatment of enteric fever in children.

Cefixime in a dose 20 mg/kg/day, orally, divided into two doses 12 h apart for a minimum of 12 days, was administered to 50 children with proven S. typhi septicaemia. Forty four of the patients were infected with strains of S. typhi resistant to multiple antibiotics including chloramphenicol, ampicillin and trimethoprim-sulfamethoxazole. All patients responded rapidly to treatment and were cured clinically and bacteriologically. Fever subsided within a mean of 5.3 days (range 3-8 days). Only two of the 50 patients treated relapsed during the 8 week follow-up period. No serious adverse reactions attributable to the drug were observed. Cefixime proved to be an effective oral drug in this open treatment trial and was associated with minimal side effects. It may provide a therapeutic alternative to the treatment of Salmonella infection with organisms multi-resistant to the standard drug regimens. Its oral formulation may provide an efficient alternative to parenteral therapy in less severely ill patients who can tolerate oral feeding.

Urea-hydrolyzing Vibrio parahaemolyticus associated with acute gastroenteritis.

A case of gastroenteritis caused by a urea-hydrolyzing strain of Vibrio parahaemolyticus is presented. Urea-hydrolyzing strains of Vibrio parahaemolyticus have rarely been reported and have not been described previously as a cause of gastroenteritis in the United States. With the exception of urea hydrolysis and the methyl red test, the isolate had all the characteristics of V. parahaemolyticus. The need to screen suspicious non-lactose-fermenting colonies from stool specimens with the oxidase test is emphasized.

Yersinia pseudotuberculosis: use of cold-temperature enrichment for isolation.

The successful isolation of Yersinia pseudotuberculosis from the stool of an asymptomatic family member of a patient with yersinia septicemia is presented. Cold enrichment permitted the isolation after 4 weeks of refrigerator incubatio,.

Enhanced host defense mechanisms with levamisole in suckling rats.

Levamisole, a synthetically produced anthelminthic agent, was administered to suckling rats that were challenged with bacterial and viral pathogens. There was no in vitro antibacterial or antiviral effect of the drug. However, enhanced survival was demonstrated in those animals treated with levamisole and challenged with Staphylococcus aureus or herpes simplex virus. The mechanism for protection against the bacteria appears to be enhancement of the primary inflammatory response. The mechanism for protection against herpes simplex virus is not yet understood.

Oral polio vaccine. Effect of booster vaccination one to 14 years after primary series.

We studied the persistence of antibody after vaccination and the response to booster revaccination with trivalent oral polio vaccine (TOPV) administered at varied intervals after the primary series in a large group of children. Decline in antibody was related to intervals since last vaccination, and not to sex, age, age at primary vaccination, or type and number of previous administrations. Geometric mean titers of neutralizing antibody were 11.3 for type 1 and 8.0 for types 2 and 3 poliovirus when vaccine had been given within the previous year, declining to 3.2, 3.0, and 2.1 for types 1, 2, and 3 after nine years. Most children with an initial titer of 4 or less responded to revaccination with a fourfold or greater increase in titer of IgG. Geometric mean titers for all three types of polio dropped to this level when last TOPV administration had been five to six years or more.

In vitro activity of ciprofloxacin compared to trimethoprim-sulfamethoxazole against Campylobacter spp., Shigella spp. and Enterotoxigenic Escherichia coli causing travellers' diarrhea in Egypt.

The in vitro activity of ciprofloxacin against bacterial enteropathogens isolated from cases of travellers' diarrhea in Egypt was compared to trimethoprim (TMP) and trimethoprim-sulfamethoxazole (SXT). No resistance to ciprofloxacin was noted for any of the Campylobacter jejuni/coli, Shigella spp., and enterotoxigenic Escherichia coli strains examined. However, resistance to TMP and SXT was noted among these same strains. Because of its broad spectrum and lack of resistance, ciprofloxacin is potentially a useful drug for the treatment of diarrhea caused by bacterial enteropathogens encountered in this region of the world.

Booster vaccination with further live attenuated measles vaccine.

Revaccination with live attenuated measles vaccine was evaluated in a large group of children to determine (1) if protective antibody to measles infection could be augmented and (2) after what interval will the revaccination yield optimal results. The rate of decline in measles hemagglutination-inhibition (HI) antibody was observed to be directly related to the time interval since the previous vaccination, and individuals with declining titers became increasingly responsive to revaccination with a maximal response approximately four to six years after previous vaccination. Six-month follow-up studies demonstrated sustained elevations in measles HI antibody titers. Measles-neutralizing antibody showed less tendency to sustain a titer increase with revaccination. The observations suggest that revaccination with live, further attenuated measles vaccine is safe and may augment immunity.

Microbiologic and clinical study of acute diarrhea in children in Aswan, Egypt.

Children with diarrhea presenting to a Government Rehydration Center in Aswan, Egypt, were investigated to determine the etiology and clinical presentation of acute childhood diarrhea in southern Egypt. Among 126 outpatients and 25 inpatients with diarrhea (mean age 18 months), enterotoxigenic Escherichia coli (ETEC) (17% of cases), Cryptosporidium (9%), Salmonella spp. (7%), Campylobacter jejuni/coli (7%), and Shigella spp. (5%) were the most common enteropathogens identified during the high incidence season of July. Enteropathogens were isolated as often from inpatients as outpatients, except for Salmonella spp. and Cryptosporidium, which were recovered more often from inpatients. Salmonella-infected children, in particular, were more ill, feverish, and dehydrated on presentation than other children, resulting in more frequent hospitalization. Except for Salmonella-infected children, children with acute diarrhea usually presented without severe dehydration, which may have been due to frequent initiation of oral rehydration therapy (ORT) by mothers trained by local health care providers. A potential environmental source of ETEC was identified in clay water storage containers commonly used in this area.

Campylobacter-associated diarrhoea in Egyptian infants: epidemiology and clinical manifestations of disease and high frequency of concomitant infections.

A diarrhoeal disease survey in Alexandria, Egypt determined the prevalence, seasonality, and household risk factors for Campylobacter-associated diarrhoea in young children. The study population was 880 children (mean age = 9.8 months) presenting with diarrhoea at one of two hospitals. A control group consisted of 1,079 healthy children (mean age = 8.8 months) attending two nearby vaccination clinics. The overall isolation frequencies for Campylobacter spp. were 16.8% for cases and 6.4% for the comparison group (p = 1 x 10(-8)). Other enteropathogens detected in diarrhoeal stools were: rotavirus (28.6%), Giardia lamblia trophozoites (21.3%), enterotoxigenic Escherichia coli (8.7%), Entamoeba histolytica (3.9%), Salmonella spp. (2.7%), and Shigella spp. (1.8%). There were few or no isolates of Aeromonas spp., Vibrio spp., Yersinia spp., or Plesiomonas spp. Comparisons among cases showed that Campylobacter spp. isolations were more prevalent during the rainy season (p = 0.001) and positively associated with keeping fowl in the home (p = 0.003) or having an outdoor source of drinking water (p = 0.029). Among Campylobacter-positive diarrhoeal patients, 69.0% had faecal leukocytes present and 16.3% had bloody stools. Patients with Campylobacter-positive diarrhoeal stools were frequently co-infected with rotavirus (28.6%) or G. lamblia (24.5%).