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The objective of this study was to determine the etiology of febrile illnesses among patients from October 1, 1993 through September 30, 1999, in the urban community of Iquitos in the Amazon River Basin of Peru. Epidemiological and clinical data as well as blood samples were obtained from consenting patients at hospitals, health clinics and private residences. Samples were tested for arboviruses in cell cultures and for IgM and IgG antibodies by ELISA. Blood smears were examined for malaria, and sera were tested for antibodies to Leptospira spp. by ELISA and microscopic agglutination. Among 6,607 febrile patients studied, dengue viruses caused 14.6% of the cases, and Venezuelan equine encephalitis virus caused 2.5%, Oropouche virus 1.0%, Mayaro virus 0.4%, and other arboviruses caused 0.2% of the cases. Also, 22.9% of 4,844 patients tested were positive for malaria, and of 400 samples tested, 9% had evidence of acute leptospirosis. Although the study was not designed to assess the importance of these pathogens as a cause of human morbidity in the total population, these results indicate that arboviruses, leptospirosis, and malaria were the cause of approximately 50% of the febrile cases. Although the arboviruses that were diagnosed can produce asymptomatic infections, our findings increased the overall understanding of the relative health burden of these infections, as well as baseline knowledge needed for designing and implementing further studies to better assess the health impact and threat of these pathogens in the Amazon Basin of Peru.

In 2017, a major outbreak of Zika virus (ZIKV) infection took place in Chincha Province, Peru, where arboviral circulation had never been reported before. We conducted a cross-sectional survey (March-May 2019) in two districts of Chincha Province: Pueblo Nuevo and Chincha Baja. We included residents who were 20 to 40 years old and who had lived in these districts for at least 1 year. Serological testing combined screening with a commercial NS1 protein-based Zika IgG ELISA, and confirmation by a cytopathic effect-based virus neutralization test (VNT). Prevalence ratios (PRs) were calculated using Poisson regression with robust error variance. Four hundred participants, divided equally among districts, were enrolled. Anti-ZIKV IgG ELISA was positive for 42 participants (10.5%) and borderline for 12 (3%). Fifty-two of these 54 samples were confirmed positive by ZIKV VNT (13% of the total population). The Pueblo Nuevo district exhibited a greater ZIKV seroprevalence based on VNT results than the Chincha Baja district (23.5% versus 2.5%), with participants from the Pueblo Nuevo district being 9.4 times more likely to have a positive ZIKV VNT result. Average monthly income greater than the minimum wage and adequate water storage were found to be protective factors (PR, 0.29 and 0.24, respectively). In multivariate analysis, living in the Pueblo Nuevo district and a personal history of fever and rash were strong predictors of ZIKV positivity by VNT. The low ZIKV seroprevalence should prompt health authorities to stimulate interventions to prevent potential future outbreaks. In the Pueblo Nuevo district, the seroprevalence was greater but presumably not sufficient to ensure protective herd immunity.

We report the case of an infant born with congenital Zika syndrome (CZS). During the largest Zika virus (ZIKV) outbreak in Peru, the mother presented with fever and rash that were confirmed to be due to ZIKV by real-time PCR. The infant was born with severe microcephaly. Imaging revealed corpus callosum dysgenesis, lissencephaly, ventriculomegaly, and calcifications. Mild hypertrophic cardiomyopathy with diastolic dysfunction was reported in the echocardiogram. Valgus deviation of the lower extremities and a left clubfoot were diagnosed at birth. The hip ultrasound showed incipient signs of Graf type II dysplasia. The findings confirm that CZS is a multiorgan phenotype in which microcephaly is merely the tip of the iceberg. A multidisciplinary approach is needed for the evaluation of these children.

Fasciola hepatica is the most widely distributed trematode-affecting humans. The Andes Mountains are highly endemic for fascioliasis. We report results of a cross-sectional study evaluating the epidemiology of Fasciola among children in 26 agricultural communities in the Cusco region of Peru. Children 3 to 16 years old were enrolled in preschools and schools. Blood from participants was tested for complete blood counts, transaminases, and Fasciola antibodies. Stool samples were tested for Fasciola and other parasites. A total of 2,515 children were included in the analysis and the mean age was 9.6 years (±3.6). Ten percent (253) of the children had at least one positive test for Fasciola, 6% had chronic infection, and 0.4% acute infection. The rest of the subjects had only antibodies against Fasciola. The prevalence of infection varied from 0% to 20% between communities. Children with evidence of Fasciola exposure were older, lived at higher altitudes, and had a lower socioeconomic status than children without infection. The logistic regression analysis showed that children from Ancahuasi district, older children, and children with higher measures of poverty were more likely to have Fasciola exposure. Fascioliasis is common in the Cusco region and associated with poverty. However, the distribution varies markedly between communities.

Hymenolepis nana is the most common cestode infection in the world. However, limited information is available regarding its impact on affected populations. We studied the epidemiology and symptoms associated with hymenolepiasis among children 3-16 years old in 16 rural communities of the highlands of the Cusco region in Peru. Information on demographics, socioeconomic status, symptoms as reported by parents, and parasitological testing was obtained from the database of an ongoing Fasciola hepatica epidemiologic study. A total of 1,230 children were included in the study. Forty-five percent were infected with at least one pathogenic intestinal parasite. Giardia spp. (22.9%) was the most common, followed by Hymenolepis (17.4%), Fasciola (14.1%), Ascaris lumbricoides (6.1%), and Strongyloides stercoralis (2%). The prevalence of Hymenolepis infection varied by community, by other parasitic infections, and by socioeconomic status. However, only years of education of the mother, use of well water, and age less than 10 years were associated with Hymenolepis infection in the multivariate analysis. Hymenolepis nana infection was associated with diarrhea, jaundice, headaches, fever, and fatigue. Children with > 500 eggs/g of stool were more likely to have symptoms of weight loss, jaundice, diarrhea, and fever. Hymenolepis nana infection and age were the only factors retained in the multivariate analysis modeling diarrhea. Hymenolepiasis is a common gastrointestinal helminth in the Cusco region and is associated with significant morbidity in children in rural communities. The impact caused by the emergence of Hymenolepis as a prevalent intestinal parasite deserves closer scrutiny., (© The American Society of Tropical Medicine and Hygiene.)

Gnathostomiasis is a zoonotic parasitosis endemic in many Asian and some Latin American countries. Most human infections are caused by Gnathostoma spinigerum in Asia and Gnathostoma binucleatum in the Americas, and recently, imported cases have been increasing among travelers returning from endemic regions. Confirmation of the clinical diagnosis relies largely on serologic tests, with a G. spinigerum-antigen-based immunoblot currently being the diagnostic method of choice. However, we repeatedly experienced that sera from patients with clinically suspected American gnathostomiasis gave negative results in this assay. Therefore, we used homologous methods to prepare G. spinigerum- and G. binucleatum-antigen-based immunoblot assays, and evaluated the cross-reactivity of the two assays. The results show incomplete cross-reactivity between the two assays: the G. spinigerum-antigen-based immunoblot apparently only detects Asian gnathostomiasis caused by G. spinigerum, whereas the G. binucleatum-antigen-based immunoblot is apparently capable of detecting American as well as Asian gnathostomiasis., (© The American Society of Tropical Medicine and Hygiene.)

AbstractIn February 2014, the Malaria Elimination Working Group, in partnership with the Peruvian Ministry of Health (MoH), hosted its first international conference on malaria elimination in Iquitos, Peru. The 2-day meeting gathered 85 malaria experts, including 18 international panelists, 23 stakeholders from different malaria-endemic regions of Peru, and 11 MoH authorities. The main outcome was consensus that implementing a malaria elimination project in the Amazon region is achievable, but would require: 1) a comprehensive strategic plan, 2) the altering of current programmatic guidelines from control toward elimination by including symptomatic as well as asymptomatic individuals for antimalarial therapy and transmission-blocking interventions, and 3) the prioritization of community-based active case detection with proper rapid diagnostic tests to interrupt transmission. Elimination efforts must involve key stakeholders and experts at every level of government and include integrated research activities to evaluate, implement, and tailor sustainable interventions appropriate to the region.

We describe a case of persistent strongyloidiasis complicated by recurrent meningitis, in a human T cell lymphotropic virus type 1 (HTLV-1) seropositive Peruvian migrant adult resettled in Italy. He was admitted with signs and symptoms of acute bacterial meningitis, reporting four other meningitis episodes in the past 6 years, with an etiological diagnosis of Escherichia coli and Enterococcus faecium in two cases. He had been previously treated with several antihelmintic regimens not including ivermectin, without eradication of strongyloidiasis, and he had never been tested for HTLV before. During the described episode, the patient was treated for meningitis with broad-spectrum antibiotic therapy and 200 μg/kg/dose oral ivermectin once daily on day 1, 2, 15 and 16 with full recovery and no further episodes of meningitis. The presented case underlines several critical points concerning the management of poorly known neglected diseases such as strongyloidiasis and HTLV infection in low-endemic areas. Despite several admissions for meningitis and strongyloidiasis, the parasitic infection was not adequately treated and the patient was not previously tested for HTLV. The supply of ivermectin and the choice of treatment scheme was challenging since ivermectin is not approved in Italy and there are no standardized guidelines for the treatment of severe strongyloidiasis in HTLV seropositive subjects., (© The American Society of Tropical Medicine and Hygiene.)

Improved tuberculosis (TB) diagnostics are required. Induced sputum sampling is superior to spontaneous sputum analysis for diagnosis of pulmonary TB. Therefore, we examined the applicability of induced sputum in primary health centers of the Peruvian TB program and studied the safety and tolerability of this procedure. We show that induced sputum is safe, inexpensive, and well-tolerated in a resource-limited environment. Widespread use of induced sputum at primary health centers can be implemented and may improve TB diagnosis., (© The American Society of Tropical Medicine and Hygiene.)

Abstract. Current regulations stipulate a yellow fever (YF) booster every 10 years. We conducted a systematic review of the protective efficacy and duration of immunity of YF vaccine in residents of disease-endemic areas and in travelers to assess the need for a booster in these two settings and in selected populations (human immunodeficiency virus-infected persons, infants, children, pregnant women, and severely malnourished persons). Thirty-six studies and 22 reports were included. We identified 12 studies of immunogenicity, 8 of duration of immunity, 8 of vaccine response in infants and children, 7 of human-immunodeficiency virus-infected persons, 2 of pregnant women, and 1 of severely malnourished children. Based on currently available data, a single dose of YF vaccine is highly immunogenic and confers sustained life-long protective immunity against YF. Therefore, a booster dose of YF vaccine is not needed. Special considerations for selected populations are detailed.

Tungiasis is an ectoparasitic skin disease caused by Tunga penetrans and Tunga trimamillata. There is a lack of histopathological studies that evaluate the recognition of this flea in tissues. We describe the ex vivo dermoscopic and the histopathological patterns of six cases and relate the findings to the developmental stage of the parasite as defined by the Fortaleza classification: two were classified as Fortaleza 3b, 3 as 4a, and 1 as 4b. Two dermoscopic patterns were observed: a brown pigmented ring and a radial crown with a central pore. The most common histopathological findings were an eosinophilic cuticle, eggs in different stages of development, tracheal rings (parasite), and basal hyperplasia (host). The eosinophilic cuticle, eggs in different stages of evolution, and tracheal rings can help to establish the diagnosis when other parts of the parasite are lacking. The Fortaleza staging may represent a tool for pathology reporting purposes.

Brucella melitensis is highly infectious for humans and can be transmitted to humans in a number of epidemiological contexts. Within the context of an ongoing brucellosis surveillance project, an outbreak at a Peruvian police officer cafeteria was discovered, which led to active surveillance (serology, blood culture) for additional cases among 49 police officers who had also eaten there. The cohort was followed up to 18 months regardless of treatment or symptoms. Active surveillance estimated the attack rate at 26.5% (13 of 49). Blood cultures from four cases were positive; these isolates were indistinguishable using multiple locus variable number tandem repeat analysis. This investigation indicates the importance of case tracking and active surveillance for brucellosis in the context of potential common source exposure. These results provide rationale for public health investigations of brucellosis index cases including the bioterrorism-related dissemination of Brucella.

Tungiasis is a neglected ectoparasitism of impoverished areas in South America and sub-Saharan Africa. The sand flea Tunga spp. preferably infests the soles and the periungueal and interdigital regions of the feet. Ectopic tungiasis is rare, even in highly endemic areas. We describe a case of an indigenous patient in Peru who presented with a nodular lesion in the extensor aspect of the knee and whose biopsy was compatible with Tunga spp. This is the first documented case of knee tungiasis in an endemic country. The historical, clinical, histological, and current epidemiological aspects of tungiasis in Peru are discussed here.

Fascioliasis is highly endemic in the Andean region of South America. Newer serological assays have improved our ability to diagnose acute fascioliasis. The diagnosis was established by Fasciola hepatica serology (Fas2-ELISA or Western blot) in 10 patients. Identifiable exposure included ingestion of watercress (N = 8), alfalfa juice (N = 5), and lettuce (N = 1). Computed tomography of the abdomen showed hepatomegaly (N = 9), track-like hypodense lesions with subcapsular location (N = 8), and subcapsular hematoma (N = 2). Radiologic sequelae included cyst calcifications detectable at least 3 years after treatment. Stool examinations were negative for F. hepatica eggs; serology was positive (Arc II [N = 2], Fas2-ELISA [N = 6], Western blot [N = 2]). The syndrome of eosinophilia, fever, and right upper quadrant pain, elevated transaminases without jaundice, hypodense liver lesions on CT, and an appropriate exposure history suggests acute fascioliasis. Fascioliasis is specifically treatable with a single dose of triclabendazole.

The prevalence, incidence, and epidemiologic factors of Clostridium difficile-associated diarrhea (CDAD) in a Peruvian hospital were studied. We conducted a cross-sectional study in patients > 14 years of age from medical/surgical wards of the Cayetano Heredia National Hospital (Lima, Peru) from September 2005 to May 2006. CDAD was defined in a case of nosocomial diarrhea when C. difficile toxin A and/or toxin B was detected by enzyme immune assay (EIA) in stools. A total of 4,264 patients were admitted, with 156 (3.7%) developing nosocomial diarrhea. Fifty-five of 156 (35.2%) cases of nosocomial diarrhea were diagnosed as CDAD. The overall incidence per 1,000 admissions was 12.9. Multivariate analysis showed that use of diapers (OR, 3.54; 95% CI, 1.71-7.34; P = 0.001) and presence of another patient with CDAD housed in the same room (OR, 2.97; 95% CI, 1.14-7.76; P = 0.026) were significantly associated with CDAD. Hospital transmission of C. difficile commonly occurred, supporting infection-appropriate measures directed toward the reduction of CDAD in low-resource settings.

The performance of Fas2-ELISA for the diagnosis of Fasciola hepatica infection in children living in areas of high endemicity for fascioliasis in the Peruvian Andes is analyzed. Fas2-ELISA is based on the detection of circulating IgG antibodies elicited in infected individuals against a F. hepatica antigen termed Fas2. The study was conducted in three Andean localities, Huertas-Julcan in Junin, Asillo in Puno, and Cajamarca, with a total population of 634 children in an age range 1 to 16 years old. Child fascioliasis prevalence was 21.1% in Huertas-Julcan, 25.4% in Asillo, and 24% in Cajamarca, estimated by coprological inspection. The seroprevalence of F. hepatica infection, determined by Fas2-ELISA, was 27.8% in Huertas-Julcan, 44.6% in Asillo, and 29.1% in Cajamarca. The overall sensitivity of Fas2-ELISA was 92.4%, the specificity 83.6%, and the negative predictive value 97.2%. No association between OD(450) Fas2-ELISA and infection intensity measured by egg counting was observed. Results show that Fas2-ELISA is a highly sensitive immunodiagnostic test for the detection of F. hepatica infection in children living in human fascioliasis endemic areas.

Little data are available on how HIV and other sexually transmitted infections (STIs) affect indigenous people in Latin America, including Peru. We conducted a sero-epidemiologic survey of HIV infection and syphilis in a native community, the Chayahuita, an indigenous population in the Amazon region of Peru. The seroprevalences of HIV and syphilis in adults were 7.5% (6 of 80) and 6.3% (5 of 80), respectively. None of the participants had ever used a condom. Male to male sexual behavior was common. At the current levels of HIV prevalence, there is the risk of a negative impact on the survival of the Chayahuita ethnic group as a whole. The outcomes of this study highlight the need for urgent medical and anthropologic approaches to stop HIV transmission in indigenous Amazonian communities.

Treatment with amphotericin B deoxycholate (AB) is associated with dose-related nephrotoxicity. We conducted an open and randomized trial to evaluate the efficacy of an oral rehydration solution (ORS) to prevent nephrotoxicity of AB, compared with an intravenous saline solution (SS). Adult patients with mucosal leishmaniasis in whom AB was indicated received either three liters or ORS or one liter of SS. Renal function tests were performed at baseline and during treatment. Forty-eight patients were included (ORS = 25, SS = 23). No difference was observed in serum creatinine, creatinine clearance, serum urea, and serum sodium values during treatment, but serum potassium values were lower in the SS group than in the ORS group (P < 0.03). Treatment was more temporarily discontinued in the SS group than in the ORS group (7 patients versus 1 patient, P = 0.02). We conclude that ORS is comparable to SS in preventing glomerular damage of AB, but more effective in preventing hypokalemia.

The objective of this study was to determine the risk factors for travelers' diarrhea (TD) reported by visitors to Cuzco, Peru. In this cross-sectional study, self-administered questionnaires looking at perceived occurrence of health problems and pre-travel health advice were obtained from departing travelers at Cuzco's International Airport between August and November 2002. A total of 5,988 travelers participated in the study. The mean age was 35 years, and 51% were women. The prevalence of TD was 24%. Factors associated with TD in the multivariable analysis were use of antibiotic prophylaxis (OR: 3.20), vaccination against cholera (OR: 1.44), history of advice for safe food and water consumption (OR: 1.46), being younger than 35 years of age (OR: 1.37), being a resident of the United States (OR: 1.28), not staying in hotels in Cuzco (OR: 1.13), and number of unsafe food or beverages consumed (OR: 1.04). Remaining in Cuzco < 1 week was a protective factor (OR: 0.58). TD is common among travelers to Cuzco. This study suggests that conventional recommendations are not invariably effective at decreasing TD.

Kaposi's sarcoma (KS) has been classified in four clinical variants (classic or Mediterranean; endemic or African; epidemic or AIDS-related; iatrogenic or immunosuppression-related). Human herpesvirus 8 (HHV-8), has been found in all these variants. We herein discuss the unusual presentation of a 53-year-old indigenous patient with purplish-brown nodular lesions on lower extremities, and miliary tuberculosis. ELISA-HIV tests were negative and immunohistochemistry (IHC) of the tumor tissue was positive for HHV-8. This is the first reported case in which the presence of HHV-8 was evidenced by means of IHC techniques in Peru. We also review all available Peruvian literature of classic KS, a disease that has been frequently reported in indigenous population of Peru since 1968, making this country a possible endemic zone of classic KS.

The role of bats as potential sources of transmission to humans or as maintenance hosts of leptospires is poorly understood. We quantified the prevalence of leptospiral colonization in bats in the Peruvian Amazon in the vicinity of Iquitos, an area of high biologic diversity. Of 589 analyzed bats, culture (3 of 589) and molecular evidence (20 of 589) of leptospiral colonization was found in the kidneys, yielding an overall colonization rate of 3.4%. Infection rates differed with habitat and location, and among different bat species. Bayesian analysis was used to infer phylogenic relationships of leptospiral 16S ribosomal DNA sequences. Tree topologies were consistent with groupings based on DNA-DNA hybridization studies. A diverse group of leptospires was found in peri-Iquitos bat populations including Leptospira interrogans (5 clones), L. kirschneri (1), L. borgpetersenii (4), L. fainei (1), and two previously undescribed leptospiral species (8). Although L. kirschenri and L. interrogans have been previously isolated from bats, this report is the first to describe L. borgpetersenii and L. fainei infection of bats. A wild animal reservoir of L. fainei has not been previously described. The detection in bats of the L. interrogans serovar Icterohemorrhagiae, a leptospire typically maintained by peridomestic rats, suggests a rodent-bat infection cycle. Bats in Iquitos maintain a genetically diverse group of leptospires. These results provide a solid basis for pursuing molecular epidemiologic studies of bat-associated Leptospira, a potentially new epidemiologic reservoir of transmission of leptospirosis to humans.

A direct relationship exists between the intensity of hookworm infection and blood loss. Other parasites may also contribute to blood loss. Our objective was to assess the relationship between the intensity of soil-transmitted helminth infections and anemia in pregnant women in a highly endemic area of Peru. Recruitment occurred between April and November 2003. Overall, 47.31% of 1,042 women had anemia (hemoglobin < 11 g/dL), 47.22% were infected with hookworm and 82.25% with Trichuris. Prevalences of infections were not associated with anemia. However, those infected with moderate and heavy intensities of hookworm infection (OR = 1.84; 95% CI: 1.06, 3.17) and those with moderate and heavy intensities of both hookworm and Trichuris infections (OR = 2.13; 95% CI: 1.10, 4.13) were more likely to suffer from anemia than women having no or light intensities. These results support routine anthelminthic treatment within prenatal care programs in highly endemic areas.

We report a case of acute, self-resolving leptospirosis presenting in a HIV-positive patient from the Peruvian Amazon. The patient presented with an undifferentiated acute febrile illness that resolved without treatment, diagnosed retrospectively as leptospirosis by serology and real-time polymerase chain reaction. Five months later, he was admitted because of a febrile illness with jaundice, hepatosplenomegaly, peripheral edema, and oral candidiasis. Because of the clinical suspicion of AIDS, stored sera of the previous admission were tested, and HIV seropositivity was confirmed, proving that the condition was present at the first admission. Acute leptospirosis in HIV coinfection is not inevitably severe, and there is probably a wide variation in clinical manifestations similar to what occurs in immuno-competent hosts.

Isolates cases and groups of patients co-infected with human T cell lymphotropic virus type I (HTLV-I) and Norwegian scabies have been previously reported. Peru is considered to be endemic for HTLV-I. Between June 1999 and December 2000, 23 patients with Norwegian scabies were enrolled in this study after written informed consent was obtained. Antibodies against HTLV-I were detected by an enzyme-linked immunosorbent assay and confirmatory Western blot. Patients ranged in age from 3 months to 84 years; 15 (65.2%) were female. Infection with HTLV-I was found in 16 (69.6%) patients. Comorbid features included corticosteroid therapy (8.6%), malnutrition (8.6%), and Down's syndrome (4.3%). Among those who consented to be tested for human immunodeficiency virus (n = 13, 56.5%), no one had a positive result. The three patients that reported one or more prior episodes of Norwegian scabies were infected with HTLV-I and two of these HTLV-I-positive patients died. Infection with HTLV-I is an important co-factor related to Norwegian scabies in Peru. In our setting, the evaluation for HTLV-I in all Norwegian scabies cases is highly recommended, especially when no other risk factors are apparent.

In 1995, the American Society of Tropical Medicine and Hygiene (ASTMH) adopted defined criteria for accreditation of clinical training programs in tropical diseases. The first data on the development, enrollment, and outcomes of such a program are presented. A nine-week Diploma course, the Gorgas Course in Clinical Tropical Medicine, given on-site in the tropics (Lima, Cusco, and Iquitos, Peru) has trained 157 individuals from 38 countries from 1996 through 2001. The average age of participants was 38.3 with 11.3 years since graduation. Graduates were 44.5% primary care physicians, 22.2% infectious diseases specialists, 12.7% emergency medicine specialists, 13.5% other specialists, and 7.1% nurses. Residents and fellows accounted for 32.8% and full-time academic faculty for 11.0%. Approximately half of all eligible Gorgas graduates have taken the ASTMH certification examination. In response to the enrollees' profiles and needs, adult learning theory has been extensively used in course design. Stable professional relationships between multiple educational partners are required for an endeavor of this scope.

An epidemiologic study was conducted to determine the prevalence of retroviral infections among people of Qucchua origin in Cuzco and Quillabamba, Peru. The study volunteers included individuals at low and at high risk for retroviral infections. Each volunteer was interviewed to obtain clinical and epidemiologic data, and to identify risk behaviors for infection. The serum was tested for human immunodeficiency virus type 1 (HIV-1) and human T cell lymphotropic virus types 1/2 (HTLV-1/2) by standard enzyme-linked immunosorbent and Western blot assays. Among a total of 370 volunteers enrolled in the study, 276 were women and 94 were men whose ages ranged between 15 and 49 years. Infection with HTLV-1 was demonstrated in 5.1% (19 of 370), and one of these, a homosexual, was also positive for HIV-1; none had HTLV-2. Overall, the rate of HTLV-1 infection was 5.3% (5 of 94) for males and 5% (14 of 276) for females. Among the low risk group of 211 healthy pregnant women, five (2.3%) were positive for HTLV-1. The rate of HTLV-1 infection in this group was significantly correlated with a history of dental surgery, as well as other surgical procedures, and a history of jaundice. Among the volunteers who practiced risk behavior(s) for retroviral infections, the positive rates for HTLV-1 were 13.7% (7 of 51) for female sex workers, 6.2% (3 of 48) for homosexuals and/or bisexuals, 8.5% (4 of 47) for patients with sexually transmitted diseases (STDs), and 0.0% (0 of 13) for promiscuous heterosexual males. In female sex workers. HTLV-1 infection was found to be significantly associated with age, a history of STDs or genital ulcers, sexual intercourse during menses, and vaginal douching (P < 0.05). A low prevalence of HIV-1 infection indicates that the virus has not yet spread significantly in these areas.

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.

We examined 141 Salmonella typhi strains of known phage type isolated during ongoing epidemiologic studies in Santiago, Chile, and Lima, Peru. Plasmids were present in 12 (17%) of 70 S. typhi isolates from Santiago and 5 (7%) of 71 isolates from Lima; these plasmids were not associated with antimicrobial resistance. Identical 21 kilobase (kb) plasmids (as defined by restriction endonuclease digest pattern) were present in 13 of the 17 plasmid-containing isolates. Virtually identical digest patterns were identified when chromosomal DNA of selected strains from Santiago, Lima, and the United States was extracted and then digested with restriction endonucleases. The similarities among plasmids and chromosomal digest patterns emphasize the homogeneity and possible clonal origin of S. typhi isolates; these data also suggest that there is only a limited role for plasmid and chromosomal analysis as a substitute for phage typing in epidemiologic studies.