Diarrheal disease incidence and morbidity among United States military personnel during short-term missions overseas

Outpatient medical surveillance of U.S. troops was conducted during 11 different overseas missions between 1981 and 1990. In addition, at the end of each of 18 overseas missions during the same period, a sample of troops was queried regarding illnesses and exposures experienced in the preceding time overseas. Diarrhea was among the leading causes of morbidity during all of these short-term missions. Diarrhea incidence rates were found to be highest during summer months, and were higher during missions to Thailand (median = 25%, range = 20-29%), Latin America (median = 26%, range = 1-43%), and northeastern Africa and southwest Asia (median = 19%, range = < 1-52%). Rates were lowest in troops deployed to the Republic of South Korea (median = 16%, range = 8-27%). During April and May 1990, a focused surveillance and questionnaire study was conducted during a five-week, joint U.S.-Thai military training exercise in central Thailand. Among 2,600 U.S. personnel, diarrheal illness was found to be the most common medical problem for troops (estimated cumulative incidence = 29%). Travel outside of the base of operations and consumption of ice were found to be important risk factors. The 10-year database analyzed for this report is the largest, published summary showing the significant impact of diarrheal diseases on U.S. military forces during short-term deployments to less developed areas.

Helicobacter pylori infection in Desert Storm troops

To determine whether military personnel deployed outside the United States are at increased risk of Helicobacter pylori infection, we evaluated U.S. Army personnel who served in the Persian Gulf from August 1990 to April 1991. Of 204 subjects from whom paired predeployment and postdeployment serum specimens were obtained, 76 (37%) were seropositive for IgG antibody to H. pylori before deployment by an enzyme-linked immunosorbent assay. Of the 111 initially seronegative subjects evaluated before and after a 7.5-month deployment, five (4.5%) seroconverted. The calculated annual seroconversion rate was 7.3%. In a postdeployment questionnaire, 62% of soldiers reported an episode of diarrhea while deployed, but there was not an increased rate of diarrhea or upper gastrointestinal symptoms in soldiers who were infected before deployment or in those who seroconverted. These data suggest that the risk of H. pylori infection increases during long-term deployment and that acute infection is not distinguishable from other gastrointestinal illnesses encountered during deployment.

Tick avoidance behaviors associated with a decreased risk of anti-tick salivary gland protein antibody seropositivity in military personnel exposed to Amblyomma americanum in Arkansas

During April through September 1990, 399 military personnel who originated from either Fort Chaffee, Arkansas (n = 236) or Fort Wainwright, Alaska (n = 163) were studied during maneuvers in tick-infested areas at Fort Chaffee. Study subjects completed a questionnaire and had pre- and post-maneuvers serum specimens analyzed for antibodies to several rickettsial and ehrlichial agents and to Amblyomma americanum (lone star tick) salivary gland proteins (anti-tick saliva antibodies [ATSA], a biologic marker of tick exposure). Military rank/grade and home station were associated with pre-maneuvers ATSA seropositivity by enzyme-linked immunosorbent assay (ELISA). Fort Wainwright personnel were more likely to show at least a 50% increase in ATSA levels, compared with subjects from Fort Chaffee, from the pre- to the post-maneuvers specimen (adjusted odds ratio [AOR] = 2.7, 95% confidence interval [CI] = 1.2-6.1). Subjects from Fort Wainwright who did not report use of bed netting were at an increased risk of post-maneuvers ATSA seropositivity (AOR = 4.1, 95% CI = 1.5-11.5). In contrast, subjects from Fort Chaffee who did not report tucking pants into socks were at increased risk of post-maneuvers ATSA seropositivity (AOR = 2.8, 95% CI = 1.1-7.1). Subjects from Fort Chaffee who reported an attached tick bite during maneuvers were more likely to be ATSA-seropositive in the post-maneuvers specimen (AOR = 2.5, 95% CI = 1.2-5.2). Western blot assays revealed large differences in tick salivary gland proteins that were recognized on the post-maneuvers specimen among three randomly selected individuals, and small differences within a single individual who reported a tick bite during maneuvers, comparing pre- and post-maneuvers specimens. The ATSA ELISA seropositivity was not associated with seroconversion to the tick-borne infectious agents.

Idiopathic epilepsy with generalized tonic clonic seizures in Antioquia, Colombia: is the joint Amerindian and Negroid racial admixture the cause of its high prevalence?

Most Colombian populations stem from the admixture of Caucasians, Amerindians and Negroids. In the world, these two latter ethnical groups show a significantly higher prevalence of epilepsy than the former one. We tested the hypothesis that the high prevalence of idiopathic epilepsy with generalized tonic clonic seizures found in the Antioquian population (Paisas), from Colombia, is due to their possible joint Negroid and Amerindian ethnic components. We have previously demonstrated that inheritance is the principal factor for developing epilepsy in this community. Analyses of racial admixture, heterogeneity between populations, genetic distance, and phyletic relationships were performed among epileptic and non epileptic samples from the Antioquian community. Also Caucasians, Spaniards, Basques, Jews, Chileans, Negroids, Amerindians and Mongoloids were included in the analysis. Four highly polymorphic blood systems were used as genetic markers: RH, MNS, ABO and FY. They were chosen because of their high discriminant power in these ethnic groups. In the population affected with idiopathic epilepsy, the estimated Negroid and Amerindian rates of admixture were low (3% and 14%, respectively). Although, these degrees of admixture can be explained due to common ancestral origins, the estimated proportion of Amerindian admixture in the epileptic affected population, was significantly higher than the estimated for the Non affected Antioquian population. The latter finding is consistent with the analysis of heterogeneity between populations that discriminated epileptic population from non epileptic Antioquian population (p < 0.05). Epileptic and non epileptic Paisas clustered in topology with Caucasians, very close to Spaniards and Basques and highly distant from Negroids and Amerindians. Thus, far, the origin of the high prevalence of idiopathic epilepsy in the Antioquian (Paisa) population cannot be explained by the hypothetical joint Negroid and Amerindian ethnical admixture, but using additional genetic markers and other methods of racial estimation of admixture it is necessary to corroborate if the Amerindian admixture component is significantly higher in the epileptic population than in the non epileptic Paisa population.

Pigmented longitudinal bands of the nail. A clinicopathologic study

Eighteen patients with pigmented longitudinal bands of the nail were evaluated. The following clinical data were obtained: age, gender, and race, duration of the pigmented bands, description and location of the lesion, history of any clinical changes; other nail changes; and family and past history. Nail matrix and/or nail bed biopsy were performed in all cases. The histopathologic findings of 18 patients with longitudinal melanonychia showed hyperpigmentation of the epidermis with no apparent increase in the number of melanocytes in 10 cases. One case showed melanoma in situ; another showed keratinocytic proliferation with focal atypia. Three cases showed subungual hemorrhage. The cause of solitary pigmented bands is often not readily apparent, making the clinical diagnosis challenging. Melanotic macule of the nail matrix, consisting of increased pigmentation of the epidermis with no apparent increased in the number of melanocytes, seems to be the most common cause. When the cause of longitudinal melanonychia is not clinically apparent, biopsy of the nail matrix and the nail bed should help to establish it.

Immunological response to Vibrio cholerae O1 infection and an oral cholera vaccine among Peruvians

A 'double-blind', randomized, placebo controlled study of an oral inactivated whole cell plus recombinant B subunit (WC/rBS) cholera vaccine was conducted during February-March 1992 in Peru in 346 military recruits, 307 (89%) of whom received 2 oral doses of vaccine or Escherichia coli K12 placebo, 2 weeks apart. Paired serum samples were obtained from 155 (50%) of the recipients of 2 doses. An epidemic of cholera took place between doses. No difference in cholera attack rates was detected between vaccine and placebo recipients after one dose (8% versus 14%). Seroconversion (4-fold or higher increase in vibriocidal antibody titres) was detected in 90% and 80% of vaccine and placebo recipients, respectively, with low pre-existing vibriocidal titres (< 0.01). The anti-cholera toxin seroconversion rate among those with low pre-existing titres was higher in vaccinated subjects (97%) than in placebo recipients (68%) (P < 0.01). Administration of 2 doses of WC/rBS vaccine concomitantly with natural V. cholerae O1 infection enhanced the serum anti-cholera toxin response. The immune response to the whole cell component of the vaccine was reduced by high pre-existing vibriocidal antibody titres.

Immunogenicity in Peruvian volunteers of a booster dose of oral cholera vaccine consisting of whole cells plus recombinant B subunit

Forty-nine subjects received two doses of oral cholera vaccine consisting of whole cells plus recombinant B subunit; this was followed by a booster dose one year later. After the primary series, a significant (greater than twofold) increase in the levels of vibriocidal, anti-cholera toxin immunoglobulin G and anti-cholera toxin immunoglobulin A antibodies occurred in 54, 88, and 81% of the subjects, respectively. Within one year, titers decreased to levels close to baseline. A booster dose then induced rises to those which occurred after the initial vaccination. The results suggest that 1-year booster doses may be necessary to maintain immunity against cholera in Latin America.

Dengue fever in U.S. troops during Operation Restore Hope, Somalia, 1992-1993

Dengue fever (DF) was considered to be a potential cause of febrile illness in U.S. troops deployed to Somalia during Operation Restore Hope in 1992-1993. A prospective study of hospitalized troops with fever and a seroepidemiologic survey of 530 troops were conducted. Among 289 febrile troops hospitalized, 129 (45%) did not have an identified cause of their fever. Dengue (DEN) virus was recovered from 41 (43%) of 96 of these patients by inoculation of admission sera into C6/36 cell cultures. Thirty-nine (41%) of the isolates were identified as DEN-2 and two (2%) as DEN-3 by an indirect immunofluorescent antibody assay. An additional 18 (49%) of 37 culture-negative cases were shown by immunoglobulin M (IgM) antibody capture enzyme-linked immunosorbent assay to have anti-DEN virus antibody. All identified DF cases recovered within 1-2 weeks; no case of dengue hemorrhagic fever or shock syndrome was observed. A seroepidemiologic survey of a unit (n = 494) with 17 culture or serologically identified DF cases and a 13% attack rate of unidentified febrile illness revealed a 7.7% prevalence of anti-DEN virus IgM antibody. Failure to use bed nets was the only identified risk factor for DEN infection (adjusted odds ratio = 2.2, 95% confidence interval = 1.4-3.0). These data indicate that DF was an important cause of febrile illness among US troops in Somalia, and demonstrate the difficulties in preventing DEN infection in troops operating in field conditions.

Community-based assessment of safety and immunogenicity of the whole cell plus recombinant B subunit (WC/rBS) oral cholera vaccine in Peru

Every year since its introduction in 1991, there have been epidemics of cholera in Lima, Peru. Vaccination is one approach to the control of cholera. A pilot study was conducted to assess the safety and immunogenicity of a whole cell plus recombinant B subunit (WC/rBS) cholrea vaccine in Lima, Peru. Five hundred and forty-one volunteers aged 2-65 years received two doses two weeks apart of WC/rBS vaccine or Escherichia coli K12 placebo administered in bicarbonate buffered water. Symptoms were monitored on all subjects and blood was collected from 102 persons before the first dose and two weeks after the second dose. Mild post-vaccination gastrointestinal symptoms were reported with equal frequency for both the vaccine and placebo recipients. Among 51 vaccines, 49% had a twofold or greater increase in serum vibriocidal titers (GMT = 78; range < 1:10 to 1:5120); and 92% and 82% developed a twofold or greater serum anti-cholera toxin IgG and IgA response, respectively. Persons with elevated prevaccination vibriocidal titers had a decreased response to the WC/rBS. Age and blood group did not affect the immune response. The WC/rBS vaccine was safe and immunogenic in a group of native Peruvians.

Safety, Immunogenicity, and Protective Efficacy of the Whole-Cell/Recombinant B Subunit (WC/rBS) Oral Cholera Vaccine Against Travelers' Diarrhea

Background: A prospective, randomized, double-blind, placebo-controlled trial of WC/rBS oral cholera vaccine was conducted in 502 U.S. college students attending summer educational programs in Mexico. Methods: Two doses of vaccine (or placebo) were administered 10 days apart immediately after arrival in Mexico. Results: The vaccine was free of significant adverse side effects. Anticholera toxin seroconversion was demonstrated in 86.7% of vaccinees compared to 8.2% of controls (p <.001). Postvaccination titers varied according to disease status (travelers' diarrhea) and enteropathogen isolated when disease developed. Protective efficacy (PE) against enterotoxigenic Escherichia coli (ETEC) diarrhea was 50% (95% CI, 14-71%), beginning 7 days after the second dose of WC/rBS. However, 74% of ETEC cases occurred within 7 days of the second dose, when no efficacy was demonstrated. Conclusions: Vaccines employed to prevent travelers' diarrhea will likely need to be administered before arrival in a developing country to be predictably beneficial. An unexpected finding was that infection with LT-ETEC after primary oral cholera immunization appears to augment the antitoxin response to WC/rBS vaccine. (J Travel Med 2:22-27, 1995)

Diarrheal disease among military personnel during Operation Restore Hope, Somalia, 1992-1993

The potential for widespread diarrheal disease was regarded as a substantial threat to U.S. troops participating in the early phases of Operation Restore Hope in Somalia. Outpatient surveillance of 20,859 U.S. troops deployed during the first eight weeks, however, indicated that a mean of only 0.8% (range 0.5-1.2%) of personnel sought care for diarrhea each week, and in three epidemiologic surveys, < 3% of troops reported experiencing a diarrheal illness per week. Despite these low overall attack rates, diarrhea accounted for 16% of 381 hospital admissions and 20% of 245 patients admitted with a temperature > or = 38.5 degrees C. Sixty-one specimens were obtained from inpatients and 52 were obtained from outpatients. Shigella sp. were isolated from 33%, enterotoxigenic Escherichia coli from 16%, Giardia lamblia from 4%, and rotavirus from 1% of 113 stool samples obtained from inpatient (61) and outpatient (52) troops with diarrhea. Bacterial isolates obtained in Somalia were resistant to doxycycline (78%), ampicillin (54%), and sulfamethoxazole (49%), but uniformly sensitive to ciprofloxacin. With the exception of 10 Shigella sonnei isolates that were linked epidemiologically to one eating facility, bacterial pathogens occurred sporadically and demonstrated a wide variation of serotypes and antibiotic sensitivity patterns. Additionally, three of 11 paired sera collected from persons with nausea, vomiting, and watery diarrhea demonstrated a four-fold or greater increase in titer to Norwalk virus antibody. These data indicate that large outbreaks of diarrheal disease did not occur; however, highly drug-resistant enteric bacteria, and to a lesser extent viral and parasitic pathogens, were important causes of morbidity among U.S. troops in Somalia.

Protective efficacy of oral whole-cell/recombinant-B-subunit cholera vaccine in Peruvian military recruits

The cholera epidemic in South America has reinforced the need for safe and effective oral vaccines. In a randomised, double-blind, placebo-controlled efficacy trial among 1563 Peruvian military recruits we have investigated the protective efficacy of an oral inactivated whole-cell/recombinant-B-subunit (WC/rBS) cholera vaccine. Participants were given two oral doses of cholera vaccine or Escherichia coli K12 placebo, with an interval of 7-14 days. 1426 (91%) subjects received the two prescribed doses and were followed up for a mean of 18 weeks (median 21 weeks). After vaccination, Vibrio cholerae O1 El Tor Ogawa was isolated from 17 subjects with diarrhoea. 16 of the cholera cases occurred 2 weeks or longer after the second dose of vaccine (14 placebo recipients, 2 vaccinees). We also detected 14 symptomless infections (11 [7 placebo recipients, 4 vaccinees]) 2 weeks or longer after the second dose. The vaccine had significant protective efficacy against cholera (86% [95% CI 37-97], p < 0.01) but not against symptomless infection (42% [-96 to 85]). All cholera cases were in people of blood group O, who made up 76% of the study population (p < 0.01). Two doses of WC/rBS vaccine, given 1 to 2 weeks apart, provide rapid, short-term protection against symptomatic cholera in adult South Americans, who are predominantly of blood group O. Long-term efficacy studies in Peruvian adults and children are under way.

Diarrheal disease in Peru after the introduction of cholera

Surveillance was conducted one day each week from December 1992 through May 1993 to determine the clinical features and etiology of diarrhea among a population in a suburban community of Lima, Peru. Patients who had had three or more loose stools during the previous 24 hr were enrolled at a clinic located in the community or at a nearby regional hospital. A total of 143 cases of diarrhea were detected for an overall rate of 7.1 cases per 1,000 population. The enteropathogens isolated were Vibrio cholerae 01 (31%), enterotoxigenic Escherichia coli (22%), and Salmonella, Shigella, Campylobacter, and Aeromonas species (10%). Specimens from the remaining cases were negative for enteropathogens. All isolates of V. cholerae were susceptible to tetracycline, doxycycline, nalidixic acid, norfloxacin, trimethoprim-sulfamethoxazole, trimethoprim, gentamicin, chloramphenicol, and cephalothin. Cases of diarrhea associated with V. cholerae were more common among adults, and more likely to experience severe dehydration and require hospitalization than the non-cholera cases. Data indicated that among the cases diagnosed, V. cholerae and enterotoxigenic E. coli were the more common causes of diarrhea in a suburban community of Lima during the summer season.

Short course albendazole treatment for neurocysticercosis in Columbia

The efficacy of albendazole was evaluated in 20 Colombian patients with neurocysticercosis showing neurological symptoms. All had parenchymal non-enhancing cystic images by computerized tomography and a positive enzyme-linked immunosorbent assay for cysticercus antibodies in serum or cerebrospinal fluid. They stayed in hospital for 8 d during treatment with albendazole, 15 mg/kg/d in 2 divided doses, and were then followed for at least 6 months after treatment. The number of cysts was reduced by 50% after 6 months. In 7 (35%) all cysts disappeared, in 7 (35%) the number was reduced, and in the remaining 6 (30%) the number was unchanged. In the 13 patients who still had cysts at 6 months, 11 showed a moderate decrease in average cyst size and in 2 the size was unchanged. Side effects during treatment were observed in 60% of the cases, but only 3 required corticosteroids.

Risk factors associated with inguinal hernias: a case control study

OBJECTIVES

To assess reported risk factors for the development of inguinal hernias, to develop a method of quantifying physical effort, and to correlate them.

DESIGN

Case control study.

SETTING

District hospital, Valencia, Spain.

SUBJECTS

290 selected patients who had undergone inguinal hernia repair, and 290 age and sex matched controls.

INTERVENTIONS

Each patient was interviewed and data collected on a specially designed questionnaire, and an "effort score" calculated.

MAIN OUTCOME MEASURES

Incidence of specified risk factors.

RESULTS

The only significant risk factor was physical effort (lifting heavy objects repeatedly over long periods of time), relative risk 2.92, 95% confidence interval 2.11 to 4.04. In addition, there were significant differences between index cases and controls in standard of education (p < 0.001), consumption of alcohol (p = 0.02), chronic cough (p < 0.001), net monthly income (p = 0.04), and amount of physical effort expended (p < 0.001). Patients with indirect hernias expended significantly more physical effort and were both heavier and taller, and patients with femoral hernias waited significantly longer than the others before having their hernias repaired.

CONCLUSION

Inguinal hernias are associated with the expenditure of a considerable amount of physical effort, and are commoner among younger, poorly educated manual workers.

Safety and immunogenicity of the oral, whole cell/recombinant B subunit cholera vaccine in North American volunteers

A newly formulated, oral, inactivated whole cell plus recombinant B subunit (WC/rBS) cholera vaccine was evaluated in US military personnel. In the first study, 74 subjects were given two doses 14 days apart. In the second study, 186 subjects were randomized into four groups; two groups received vaccine with either full (4 g) or half (2 g) strength bicarbonate buffer, and two groups received either full or half strength buffer without vaccine. Mild gastrointestinal symptoms were associated with full buffer (P = .02) but not with the vaccine. In the first study, 36% of all subjects and 55% with low prevaccination titers (< 1:40) had a > or = 2-fold rise in vibriocidal antibody level; > 80% of subjects developed a 4-fold rise in anti-cholera toxin (CT) titers. Post-vaccination IgA and IgG anti-CT titers were approximately 1.5-fold higher among persons receiving full strength buffer (P = .05). The WC/rBS vaccine is safe and immunogenic in North Americans, although some mild gastrointestinal symptoms occur with the high concentration of buffer necessary to protect the B subunit from gastric acid denaturation. Prior immunity to cholera conferred by parenteral vaccine decreased vibriocidal antibody response.

Epidemiologic investigation of an outbreak of cutaneous leishmaniasis in a defined geographic focus of transmission

An outbreak of cutaneous leishmaniasis occurred in a unit of 608 Puerto Rican national guardsmen conducting jungle warfare training in the Panama Canal Area in July 1984. An epidemiologic investigation of reported nonhealing, ulcerating skin lesions was conducted among 540 (89%) unit members in November and December 1984. Fifteen (88%) of 17 individuals with chronic, ulcerating skin lesions were confirmed as cases of cutaneous leishmaniasis by culture or histopathology. Twelve cases yielded positive Leishmania cultures, identified as L. braziliensis panamensis by cellulose acetate electrophoresis. Evaluation of different diagnostic techniques revealed that direct examination of tissues by Giemsa-stained histological examination was the most sensitive test (87% sensitivity), with an indirect immunofluorescent antibody test being rather insensitive (67%). All but one of the confirmed cases operated in small units that trained and slept overnight at a mortar firing site for a period of three days, yielding a site-specific attack rate of 22% (14 of 64). This contrasted with a much lower attack rate of 0.2% (1 of 476), experienced by unit members who trained at other locations during the same time frame (P less than 0.001). The median incubation period calculated from day of arrival at the mortar firing site was 17 days (range 2-78) for the 15 confirmed cases. Available personal protection methods, such as the use of insect repellents, were not appropriately implemented by unit personnel and thus, were not found to effectively protect against Leishmania infection. This is the largest reported outbreak of cutaneous leishmaniasis in military personnel associated with a single geographic focus of infection and contrasts with the usual sporadic disease experience in Panama.

A cluster of tick-borne infections: association with military training and asymptomatic infections due to Rickettsia rickettsii

During the spring of 1989, 86 members of a military unit from the state of Maryland, USA, participated in two-week-long training manoeuvres in the states of Arkansas (location FC) and Virginia (location FAPH). Acute febrile illnesses due to infections with two tick-borne pathogens, Rickettsia rickettsii and Ehrlichia sp., were confirmed serologically in 2 initial cases who were admitted to the hospital. A seroepidemiological investigation among unit members found an additional 17 of 109 individuals (16%) with elevated post-exposure indirect immunofluorescent antibody (IFA) titres to R. rickettsii (16 cases) and/or E. canis (2 cases). The seropositivity rate of personnel who trained at FC was 38% (15 of 40), compared to only 13% (4 of 31) and 8% (3 of 38) of personnel who trained at FAPH or who did not train in the field, respectively (P < 0.001). Seropositivity was associated with symptoms suggestive of a tick-borne illness. Only 4 (22%) and 6 (33%) of the 18 personnel seropositive for R. rickettsii reported an erythematous or petechial type of rash or a febrile illness, respectively, within 4 weeks of exposure; 5 of 18 (28%) personnel infected with R. rickettsii reported no symptoms and only 8 of 18 (44%) received medical treatment. Mild infections with R. rickettsii, or a closely related spotted fever group agent, may have accounted for the high infection rate experienced by this group.

Treatment of traveler's diarrhea with ciprofloxacin and loperamide

To determine the efficacy of loperamide given with long- and short-course quinolone therapy for treating traveler's diarrhea, 142 US military personnel were randomized to receive a single 750-mg dose of ciprofloxacin with placebo, 750 mg of ciprofloxacin with loperamide, or a 3-day course of 500 mg of ciprofloxacin twice daily with loperamide. Culture of pretreatment stool specimens revealed campylobacters (41%), salmonellae (18%), enterotoxigenic Escherichia coli (ETEC, 6%), and shigellae (4%). Of the participants, 87% completely recovered within 72 h of entry. Total duration of illness did not differ significantly among the three treatment groups, but patients in the 3-day ciprofloxacin plus loperamide group reported a lower cumulative number of liquid bowel movements at 48 and 72 h after enrollment compared with patients in the single-dose ciprofloxacin plus placebo group (1.8 vs. 3.6, P = .01; 2.0 vs. 3.9, P = .01). While not delivering a remarkable therapeutic advantage, loperamide appears to be safe for treatment of non-ETEC causes of traveler's diarrhea. Two of 54 patients with Campylobacter enteritis had a clinical relapse after treatment that was associated with development of ciprofloxacin resistance.

Isolation and characterization of an Ehrlichia sp. from a patient diagnosed with human ehrlichiosis

A new disease was recognized in the United States in 1986. The etiologic agent, although not previously isolated from a human, appeared to be serologically related to Ehrlichia canis, a canine leukotropic rickettsia. We obtained blood specimens from 27 febrile patients with a history of tick exposure. Leukocytes from 24 patients not treated with tetracycline were placed onto a monolayer of DH82 cells. We performed indirect immunofluorescence on sera from all 27 febrile patients as well as sera from 12 patients with previously diagnosed ehrlichiosis. Intractoplasmic inclusions were first observed in culture 35 days after the addition of infected blood from one patient. Partial sequencing of the rRNAs from the human isolate and E. canis indicated that they are 98.7% related. Positive indirect immunofluorescence reactions to the human isolate were obtained for all 12 previously diagnosed patients and for 33% of the 27 febrile patients. Two patients were seropositive for the human isolate but not for E. canis. No sera were positive for E. canis and negative for the human isolate. We report the isolation of a previously unrecognized Ehrlichia sp. that appears to be the etiologic agent of human ehrlichiosis. Serologic data (range of antibody titers, 256 to 32,768) in combination with rRNA sequencing indicated that the newly isolated Ehrlichia sp. is similar, but not identical, to E. canis.

Treatment of travelers' diarrhea: ciprofloxacin plus loperamide compared with ciprofloxacin alone. A placebo-controlled, randomized trial

OBJECTIVE

To compare the safety and efficacy of loperamide used in combination with ciprofloxacin or ciprofloxacin alone for the treatment of travelers' diarrhea.

DESIGN

Double-blind, placebo-controlled, randomized clinical trial.

SETTING

United States Army hospital in Egypt.

PARTICIPANTS

United States military personnel with travelers' diarrhea (n = 104) during a military exercise in November 1989. Persons who were noncompliant, had bloody diarrhea, or had received antidiarrheal medications before entry into the study were excluded.

INTERVENTIONS

All participants with travelers' diarrhea were treated with ciprofloxacin, 500 mg twice daily for 3 days. Fifty of these patients were randomly assigned to receive loperamide, a 4-mg first dose and 2 mg for every loose stool (as much as 16 mg/d), and 54 were randomly assigned to receive placebo.

MEASUREMENTS

Enterotoxigenic Escherichia coli was isolated from 57% of patients; Shigella and Salmonella, seen in 4% and 2% of patients, respectively, were not common.

MAIN RESULTS

After 24 hours, the symptoms of 82% of patients in the ciprofloxacin and loperamide group compared with 67% in the ciprofloxacin and placebo group had improved or fully recovered (odds ratio, 2.3; 95% CI, 0.8 to 6.3; P = 0.08). After 48 hours, the symptoms of 90% of both groups had improved or fully recovered. The mean number of stools for those receiving loperamide was not much lower than those who did not receive loperamide after 24 hours (1.9 +/- 0.2 [SE] compared with 2.6 +/- 0.2) or 48 hours (3.1 +/- 0.3 compared with 4.0 +/- 0.3) of treatment (P = 0.19).

CONCLUSIONS

In a region where enterotoxigenic E. coli was the predominant cause of travelers' diarrhea, loperamide combined with ciprofloxacin was not better than treatment with ciprofloxacin alone. Loperamide appeared to have some benefit in the first 24 hours of treatment in patients infected with enterotoxigenic E. coli. Both regimens were safe.

Parasitological evaluation of a foodhandler population cohort in Panama: risk factors for intestinal parasitism

A nonconcurrent, prospective intestinal parasitic disease study in a group of 200 foodhandlers employed in the Panama Canal Area was conducted in mid-1985 as part of an established occupational health medical surveillance program. The study included a review of laboratory testing (i.e., coprological exam), preexisting medical record data, and patient interview information to calculate estimates of incidence and risk factors associated with acquisition of Giardia lamblia and other protozoan/helminthic intestinal parasites. Significant increases in risk of infection were detected for specific native Indian and West Indian employee groups when compared with their Hispanic Panamanian (i.e., Latinos) or North American (i.e., U.S. born) counterparts. A three- to fourfold higher rate of infection was also documented during a one-year period when semiannual rather than annual examinations were conducted. No difference in the therapeutic efficacy of parasitological cure of Metronidazole versus Quinacrine was found when used in the treatment of individuals with asymptomatic G. lamblia infections (85% in both groups). The appropriateness of mass therapy of asymptomatically infected foodhandlers is discussed.

Isolation of a newly recognized Bunyamwera serogroup virus from a febrile human in Panama

A virus, strain 86MSP18, was isolated from the acute phase serum of a U.S. soldier with a febrile illness. He was stationed at Fort Sherman in the Republic of Panama when the onset of his illness occurred. A rise in neutralizing antibody to the viral isolate was observed between the patient's acute and convalescent-phase serum samples. Virus strain 86MSP18 has been shown by plaque reduction neutralization to be closely related to but distinct from Cache Valley virus and known subtypes. It appears to be a newly recognized subtype of Cache Valley virus and is believed to be the second isolation of a Cache Valley virus subtype from a human with a febrile illness. The name "Fort Sherman" virus for strain 86MSP18 is proposed.

Bowenoid papulosis: clinical and histological study of eight cases

Eight cases of bowenoid papulosis are reported. The clinical diagnoses were confirmed by histology. In one case an immunoperoxidase method showed the presence of papillomavirus antigen in the nucleus of the most superficial epidermal cells. We consider bowenoid papulosis to be a condition with specific features that distinguish it clinically and histologically from carcinoma in situ and condylomata acuminata.

Erythema nodosum leprosum: nature and extent of the cutaneous microvascular alterations

Skin biopsy specimens from four patients with erythema nodosum leprosum, when examined as Epon-embedded, 1-micron sections, exhibited a necrotizing vasculitis involving capillaries, venules, and small-to-medium arteries and veins. In the superficial dermis, affected venules and capillaries showed endothelial cell enlargement and focal necrosis associated with perivascular infiltrates of lymphocytes. In the deep dermis and subcutaneous tissue, affected venules, arterioles, and arteries exhibited endothelial cell necrosis and matted fibrin in the vessel walls associated with perivascular infiltrates of neutrophils. Throughout the dermis, mononuclear phagocytes with vacuoles containing numerous fragmented organisms were observed. By electron microscopy, electron-dense material resembling immune complexes was observed in the walls of these vessels. These observations support the concept that erythema nodosum leprosum is an immune complex-mediated necrotizing vasculitis involving capillaries, arterioles, arteries, venules, and veins.

Histopathologic evaluation of melanocytic nervi in oculocutaneous albinism

This is a report of the histopathologic findings of melanocytic nevi in patients with oculocutaneous albinism. Seven albino patients, four tyrosinase positive and three tyrosinase negative, with a total of 34 melanocytic lesions were available for examination. The specimens were examined histopathologically for the presence of intranuclear pseudoinclusions, giant melanocytic cells, eosinophilic globules, features of congenital nevi, and atypical changes. A statistically significant increased number of giant melanocytic cells were found in intradermal nevi (p less than 0.0025), compound nevi (p less than 0.01), and junctional nevi of the patients with albinism compared with controls. Eosinophilic globules were found in 17% of the 34 nevi, and congenital features in 8.8%. All lesions showed adequate maturation of cells with no atypical changes. Marked solar elastosis was found in the dermis around and beneath the nevi, even though most lesions were in covered areas.

An efficacy trial of doxycycline chemoprophylaxis against leptospirosis

Because leptospirosis has been an important cause of morbidity in U.S. soldiers training in the Republic of Panama, we conducted a randomized, double-blind, placebo-controlled field trial during the fall of 1982 to determine whether doxycycline was an effective chemoprophylactic agent against this infection. Doxycycline (200 mg) or placebo was administered orally on a weekly basis and at the completion of training to 940 volunteers from two U.S. Army units deployed in Panama for approximately three weeks of jungle training. Twenty cases of leptospirosis occurred in the placebo group (an attack rate of 4.2 per cent), as compared with only one case in the doxycycline group (attack rate, 0.2 per cent, P less than 0.001), yielding an efficacy of 95.0 per cent. This study demonstrated the value of doxycycline as a prophylactic drug against leptospirosis.

Collagenous papules on the aural conchae

Four cases of a new entity characterized by papules that are smooth in surface and unchanged in color on the aural conchae are reported. Histologically they are characterized by sclerotic and hyalinized masses within thickened dermis and by special stains and electron microscopy are revealed to consist of altered collagen.

Melasma: a clinical, light microscopic, ultrastructural, and immunofluorescence study

Melasma is an acquired brown hypermelanosis of the face. Although it is thought that melasma is associated with multiple etiologic factors (pregnancy, gastric, racial, and endocrine), one of the primary causes of its exacerbation appears to be exposure to sunlight. Three patterns of melasma are recognized clinically: (1) a centrofacial pattern, (2) a malar pattern, and (3) a mandibular pattern. Examination of patients with Wood's light (320--400 nm) is useful in classifying the specific type of melasma in correlation with the localization of pigment granules (melanosomes) in the epidermis and dermis. Four types of melasma are described on the basis of Wood's light examination: (1) an epidermal type, (2) a dermal type, (3) a mixed type, and (4) a fourth type, described in patients of dark complexion, in which the lesions, for lack of contrast, are not discernible on Wood's light examination, perhaps due to the increased number of melanosomes in the normal skin of black individuals. Light, histochemical, and electron microscopic studies revealed an increase in number and activity of type-specific melanocytes which appeared to be engaged in increased formation, melanization, and transfer of pigment granules (melanosomes) to the epidermis as well as to the dermis. The melanocyte seems to undergo a functional alteration brought about by a combination of multiple factors, including persistent sun exposure, hormonal factors, and genetic predisposition.

An adjustable sterile lead apron for radiation protection during angiography

A simple sterile lead apron can be mounted directly on any vertical-beam image-intensifier housing and readjusted by the angiographer to shield himself from scatter during fluoroscopy and cineangiocardiography, even if the image intensifier is titled in the longitudinal plane. Properly placed, the apron effectively reduces exposed due to scatter.