bluuebunny/crossref_metadata_2025 huggingface dataset:
Short report: identification of the likely etiologic agent of human trichinellosis in Sicily (Italy) between 1933 and 1946.
Authors: Pozio E , La Rosa G
Published: May 2017

Larvae of Trichinella sp. collected in 1961 from muscle samples of the last infected domestic pig slaughtered in Sicily (Italy), and preserved in absolute ethyl alcohol until 1997, have been identified as Trichinella spiralis by the polymerase chain reaction. This finding explains the severity of the clinical picture, resulting in death, and the high number of fatal cases (20 of 184, 11%) observed in three Sicilian outbreaks between 1933 and 1945, caused by the consumption of sausages from pigs originating from the same focus of 1961. The relationship between the human outbreaks and the infected pig of 1961 is supported by epidemiologic data that show that Sicily was and is Trichinella-free, with the exception of the above reported focus.
Field study on the distribution of Entamoeba histolytica and Entamoeba dispar in the northern Philippines as detected by the polymerase chain reaction.
Authors: Rivera W L , Tachibana H , Kanbara H
Published: May 2017

We used the polymerase chain reaction (PCR) to study the distribution of Entamoeba histolytica and E. dispar in 1,872 individuals in 14 communities in the northern Philippines. Here we report a field study using a DNA extraction protocol from formalin-fixed stool specimens as previously reported. This assay detected 137 stools (7.318%) containing E. dispar and 18 stools (0.961%) containing E. histolytica. The most affected age group for E. histolytica/E. dispar infections were those 5-14 years of age. There was no significant difference in the sex distribution of E. histolytica, while in the case of E. dispar, a higher prevalence was observed in females (9.186%) than in males (5.731%) (P < 0.01). An apparent clustering of stool-positive cases of E. histolytica and E. dispar was also observed in the northern part of the study area. The results of this survey demonstrate that E. dispar is highly prevalent in the communities studied. Moreover, it offers promise for the PCR using DNA extracted from formalin-fixed stools as a sensitive epidemiologic tool for detecting E. histolytica and E. dispar infections.
Recovery of waterborne oocysts of Cyclospora cayetanensis by Asian freshwater clams (Corbicula fluminea).
Authors: Graczyk T K , Ortega Y R , Conn D B
Published: May 2017

Asian freshwater clams (Corbicula fluminea) were exposed for 24 hr in 38 liters of water contaminated with 1.0 x 10(5) Cyclospora cayetanensis oocysts (2.6 x 10(3) oocysts/L). The hemolyph and gill smears of 30 clams were examined by acid-fast stain on days 1, 3, 5, 7, 10, 13, and 18 postexposure (PE). Since no oocysts were detected in the water 24 hr after contamination by the membrane filter-dissolution method, the oocyst retention rate was 4.6 X 10(2) oocysts/clam. The prevalence of oocyst-positive clams significantly decreased (P < 0.01) from 93% to 47% during 13 days PE. None of the clams contained oocysts on day 18 PE; no oocysts were detected in the clam feces. The numbers of oocysts recovered from six clam size classes varied and significantly decreased with smaller clam size (P < 0.01). The lowest prevalence values of oocyst-positive clams, 45% and 34%, were observed in the two lowest size classes: 12.1-14.0 mm and 14.1-16.0 mm, respectively. The prevalence values in the remaining four classes ranged from 84% to 100%. The sampling program demonstrated that the population of 180 clams examined during the study up to 13 day PE could be assessed for C. cayetanensis positivity by random testing of a minimum of 75 clams (42%). When the two lowest clam size classes are eliminated, the population of 114 clams could be assessed by sampling a minimum of 32 clams (28%). The results demonstrate that Corbicula fluminea can recover waterborne oocysts of C. cayetanensis, and could be used as biological indicators of contamination of water with C. cayetanensis oocysts.
Human leptospirosis in the Seychelles (Indian Ocean): a population-based study.
Authors: Yersin C , Bovet P , MÃ©rien F , Wong T , Panowsky J , Perolat P
Published: May 2017

A leptospirosis surveillance program was carried out for 12 months on the entire population of the Seychelles. Diagnosis was assessed by both microagglutination test and polymerase chain reaction (PCR) assay. In this population of 74,331, leptospirosis was clinically suspected in 125 subjects and confirmed in 75 patients (incidence of 101 per 100,000; 95% confidence interval = 79-126). Leptospirosis was more frequent in middle-aged males with environmental exposure. Eight serogroups were identified and Icterohaemorrhagiae (31%) and Hurstbridge (20%) were the most frequent. Hurstbridge, a recently identified new serogroup, was implicated in severe cases and death. Influenza-like forms accounted for 37% of the cases while jaundice, acute renal failure, and pulmonary hemorrhage occurred in 52%, 28%, and 19%, respectively. Death occurred in six patients and was related to pulmonary hemorrhage. The PCR result was positive after completion of treatment in eight patients, suggesting that the administered five-day course of penicillin may be inadequate to eradicate the bacteria.
Comparative studies on the antibody repertoire produced by susceptible and resistant mice to virulent and nonvirulent Paracoccidioides brasiliensis isolates.
Authors: Vaz C A , Singer-Vermes L M , Calich V L
Published: May 2017

The specific recognition pattern of antibodies produced by susceptible and resistant mice infected with the low virulence Paracoccidioides brasiliensis isolate (Pb265) was examined by an immunoblotting procedure and compared with that of antibodies produced by highly virulent isolate (Pb18) in infected mice. Both mouse strains produced IgG antibodies to 13 of the 16 major antigen bands, and showed a recognition pattern similar to sera from mice infected with the virulent isolate. Nevertheless, the reaction to components interposed among major bands (intermediate antigen bands of 75, 73, 68, 64, 33, 23, 22, and 12.5 kD) were detected exclusively with antibodies raised in response to the virulent P. brasiliensis isolate independent of the resistance pattern of the host. It was also demonstrated here that the most diversified repertoire of specific IgA was produced when the susceptible host and virulent fungus were associated.
Immunoepidemiology of Dracunculus medinensis infections I. Antibody responses in relation to infection status.
Authors: Bloch P , Simonsen P E
Published: May 2017

The specific serum IgG1, IgG4, and IgE responses to Dracunculus medinensis and the level of total IgE of individuals living in a highly endemic area of northern Ghana were measured by ELISA. Sera were obtained in the high transmission season from individuals with prepatent, patent, or postpatent infection as well as from individuals from the same endemic area who claimed to have never had a patent infection (i.e., endemic normal individuals). Individuals with prepatent or postpatent infections responded with a significantly lower mean level of specific IgG1 and IgG4 compared with individuals with a patent infection, and with a significantly higher mean level of specific IgG1 and IgG4 compared with endemic normal individuals. For specific IgE, no differences were found in the mean antibody level between the infection status categories. Individuals with a patent infection had a significantly lower mean serum level of total IgE compared with prepatent, postpatent, and endemic normal individuals. Endemic normal individuals had the highest mean level of total IgE. Furthermore, in all clinical categories, high responders for specific IgG1 and IgG4 generally had low levels of total IgE, whereas low responders for specific IgG1 and IgG4 generally had high levels of total IgE. A similar dichotomy, although less distinct, was observed between specific IgG1 and IgG4 on the one hand and specific IgE on the other. Thus, similar to what has been suggested for schistosomiasis and lymphatic filariasis, the relationship between the IgG subclasses and IgE appears to play a role in, or at least to reflect, a mechanism for protective immunity in dracunculiasis.
Risk factors for gametocyte carriage in uncomplicated falciparum malaria.
Authors: Price R , Nosten F , Simpson J A , Luxemburger C , Phaipun L , ter Kuile F , van Vugt M , Chongsuphajaisiddhi T , White N J
Published: May 2017

The factors affecting the development of patent Plasmodium falciparum gametocytemia were assessed in 5,682 patients entered prospectively into a series of antimalarial drug trials conducted in an area of low and seasonal transmission on the western border of Thailand. Of the 4,565 patients with admission thick smear assessments, 110 (2.4%) had gametocytemia. During the follow-up period 170 (3%) of all patients developed patent gametocytemia, which in 89% had developed by day 14 following treatment. In a multiple logistic regression model five factors were found to be independent risk factors at presentation for the development or persistence of gametocytemia during follow up; patent gametocytemia on admission (adjusted odds ratio [AOR] = 7.8, 95% confidence interval [CI] = 3.7-16, P < 0.001), anemia (hematocrit <30%) (AOR = 3.9, 95% CI = 2.3-6.5, P < 0.001), no coincident P. vivax malaria (AOR = 3.5, 95% CI = 1.04-11.5, P < 0.04), presentation with a recrudescent infection (AOR = 2.3, 95% CI = 1.3-4.1, P < 0.004), and a history of illness longer than two days (AOR = 3.3, 95% CI = 1.7-6.6, P < 0.001). Patients whose infections responded slowly to treatment or recrudesced subsequently were also more likely to carry gametocytes than those who responded rapidly or were cured (relative risks = 1.9, 95% CI = 1.3-2.7 and 2.8, 95% CI = 2.0-4.0, respectively; P < 0.001). These data provide further evidence of important epidemiologic interactions between P. falciparum and P. vivax, and drug resistance and transmission potential.
Does the availability of blood slide microscopy for malaria at health centers improve the management of persons with fever in Zambia?
Authors: Barat L , Chipipa J , Kolczak M , Sukwa T
Published: May 2017

Some Ministries of Health in Africa plan to make blood slide microscopy available in peripheral health centers to improve malaria diagnosis over the current practice, which relies solely on clinical findings. To assess whether microscopy improves the management of febrile persons in health centers, we prospectively reviewed medical records of all outpatients visiting six health centers with laboratories in Zambia during a 2-3-day period. Staff interviews and a blinded review of a series of blood slides from each facility by two expert microscopists were also conducted. Of 1,442 outpatients, 655 (45%) reported fevers or had a temperature > or = 37.5 degrees C. Blood slide microscopy was ordered in 28-93% of patients with fever (mean = 46%). Eighty-eight (35%) patients without parasitemia were prescribed an antimalarial drug. Antimalarial drugs were prescribed with equal frequency to those who were referred for a blood slide (56%) and those not referred (58%). The sensitivity of microscopy was 88% and the specificity was 91%. Use of malaria microscopy varied widely, indicating that clinicians are not using standard criteria for ordering this test. Although diagnosis by microscopy was generally accurate, it appeared to have had little impact on the treatment of persons with fever. Guidelines for using blood slide microscopy are needed and prescription of antimalarial drugs should be discouraged when slide results are negative.
Comparison of the immunogenicity and safety of two 17D yellow fever vaccines.
Authors: Lang J , Zuckerman J , Clarke P , Barrett P , Kirkpatrick C , Blondeau C
Published: May 2017

As part of the clinical validation process of a new working seed of a licensed yellow fever vaccine (new working seed PV26, Stamaril; Pasteur MÃ©rieux Connaught, Lyon, France), the immunogenicity and safety of two batches of this vaccine (PM-YF) were compared with those of another commercially available vaccine (Arilvax; Evans Medical-Wellcome, Liverpool, United Kingdom) in 211 healthy adults. While the geometric mean titer values at days 10-14 and day 28 after vaccination were higher in the PM-YF group, the vaccines provided equivalent seroprotection (titers > or = 1/10) one month after a single vaccine dose (100% PM-YF versus 99% W-YF; P = 0.001, by one-sided equivalence test). Both vaccines were safe. There were no serious local or systemic reactions reported, nor any clinically significant hepatic function abnormalities associated with the use of either vaccine. These two 17D yellow fever vaccines from different European vaccine manufacturers were highly immunogenic and safe, and provided equivalent seroprotection.
First do no harm: making oral rehydration solution safer in a cholera epidemic.
Authors: Daniels N A , Simons S L , Rodrigues A , Gunnlaugsson G , Forster T S , Wells J G , Hutwagner L , Tauxe R V , Mintz E D
Published: May 2017

Oral rehydration solution (ORS) is lifesaving therapy for cholera and pediatric diarrhea. During a cholera epidemic in Guinea-Bissau, we evaluated the microbiologic quality of ORS prepared at a hospital and tested a simple intervention using special vessels for disinfecting tap water with bleach and for preparing, storing, and dispensing ORS. Few coliform bacteria and Escherichia coli were recovered from tap water; however, pre-intervention ORS contained numerous bacteria including E. coli and toxigenic Vibrio cholerae O1. In contrast, ORS samples from intervention vessels had few or no coliform bacteria, no E. coli, and no V. cholerae. Mean pre-intervention counts of coliform bacteria (3.4 x 10(7) colony-forming units [cfu]/100 ml) and E. coli (6.2 x 10(3) cfu) decreased significantly during the intervention period to 3.6 x 10(2) cfu and 0 cfu, respectively (P < 0.001). This simple system using bleach disinfectant and special storage vessels prevents bacterial contamination of ORS and reduces the risk of nosocomial transmission of cholera and other enteric pathogens.
Isolation of Fusobacterium necrophorum from cancrum oris (noma).
Authors: Falkler W A , Enwonwu C O , Idigbe E O
Published: May 2017

A study of the predominant microflora in active sites of noma (cancrum oris) lesions was carried out in eight noma patients 3-15 years of age in Sokoto State in northwestern Nigeria. Paper point sampling and conventional anaerobic microbiologic techniques were used. Fusobacterium necrophorum was recovered from 87.5% of the noma lesions. Oral microorganisms included Prevotella intermedia, alpha-hemolytic streptococci, and Actinomyces spp. which were isolated from 75.0%, 50.0%, and 37.5% of the patients, respectively. Peptostreptococcus micros, Veillonella parvula, Staphylococcus aureus, and Pseudomonas spp. were each recovered from one lesion. The F. necrophorum and P. intermedia isolates were tested for antibiotic sensitivity to clindamycin, tetracycline, metronidazole, and penicillin using the E-test, and all strains were observed to be sensitive to all of the antibiotics tested with the exception of one strain of P. intermedia, which showed resistance to penicillin. The first reported isolation from human noma lesions of F. necrophorum, a pathogen primarily associated with animal diseases, may have important etiologic and animal transmission implications.
Comparison of five methods of malaria detection in the outpatient setting.
Authors: Lema O E , Carter J Y , Nagelkerke N , Wangai M W , Kitenge P , Gikunda S M , Arube P A , Munafu C G , Materu S F , Adhiambo C A , Mukunza H K
Published: May 2017

In eastern Africa where 90% of the malaria is due to Plasmodium falciparum, the accuracy of malaria diagnosis at the outpatient level is becoming increasingly important due to problems of drug resistance and use of alternative, costly antimalarial drugs. The quantitative buffy coat (QBC) technique, acridine orange staining with an interference filter system, and the ParaSight-F test have been introduced as alternative methods to conventional microscopy for the diagnosis of malaria. Two hundred thirteen outpatients were tested using these alternative methods and conventional microscopy by five experienced technologists; two were randomly allocated to read the results of each test. Paired results showed the highest level of agreement with the ParaSight-F test (99%), followed by Field stain (92%). The results of the QBC technique showed the least agreement (73%). Using conventional microscopy as the reference standard, the ParaSight-F test had a sensitivity range of 90-92% and a specificity of 99%, staining with acridine orange had a sensitivity range of 77-96% and a specificity range of 81-98% and the QBC technique had a sensitivity range of 88-98% and a specificity range of 58-90%. All microscopic tests showed lower sensitivities (as low as 20% using staining with acridine orange) in detecting low parasitemias (< or = 320/microl) than the ParaSight-F test (70%). Due to the high cost of the ParaSight-F test, Field-stained blood films remain the most appropriate method for diagnosis of P. falciparum in eastern Africa. The ParaSight-F test may be used in situations where no trained microscopists are available, or where malaria is strongly suspected and the results of microscopy are negative.
Serum levels of thrombomodulin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin in the acute phase of Plasmodium vivax malaria.
Authors: Ohnishi K
Published: May 2017

Elevated plasma or serum levels of thrombomodulin (TM), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin have been reported in several diseases. However, plasma or serum levels of TM, ICAM-1, VCAM-1, and E-selectin have not been investigated in the acute phase of Plasmodium vivax malaria. Serum TM, ICAM-1, VCAM-1, E-selectin, and creatinine levels were determined in six Japanese patients in the acute phase of vivax malaria and in seven healthy Japanese controls. Parasitemias of the peripheral blood were < 0.1% in five patients and 0.8% in one patient. The patients' mean +/- SD serum levels of TM, ICAM-1, VCAM-1, and E-selectin were 5.7 +/- 1.3 Fujirebio units/ml, 709 +/- 397 ng/ml, 2,112 +/- 782 ng/ml, and 99 +/- 28 ng/ml, respectively, and all were significantly greater than those in the controls (TM; P < 0.005, ICAM-1; P < 0.025, VCAM-1; P < 0.005, E-selectin; P < 0.025). However, no significant difference was identified between patients and controls for serum creatinine values. The serum levels of TM and VCAM-1 were not related to parasitemia. The elevation of serum TM levels suggests that endothelial cell damage occurs in the acute phase of vivax malaria.
Neurocysticercosis in an Italian traveler to Latin America.
Authors: Chatel G , Gulletta M , Scolari C , Bombana E , El-Hamad I , Matteelli A , Carosi G
Published: May 2017

Neurocysticercosis is rarely reported in short-term travelers, although the disease remains a major public health problem in tropical regions. We present a case of neurocysticercosis that was probably acquired by ingestion of Taenia solium eggs contained in the stomach of a pig butchered by the traveler. Complete clinical resolution was obtained by medical treatment, underlying the importance of early suspicion and diagnosis of the disease.
Transmission of epidemic Vibrio cholerae O1 in rural western Kenya associated with drinking water from Lake Victoria: an environmental reservoir for cholera?
Authors: Shapiro R L , Otieno M R , Adcock P M , Phillips-Howard P A , Hawley W A , Kumar L , Waiyaki P , Nahlen B L , Slutsker L
Published: May 2017

Sub-Saharan Africa has the highest reported cholera incidence and mortality rates in the world. In 1997, a cholera epidemic occurred in western Kenya. Between June 1997 and March 1998, 14,275 cholera admissions to hospitals in Nyanza Province in western Kenya were reported. There were 547 deaths (case fatality rate = 4%). Of 31 Vibrio cholerae O1 isolates tested, all but one were sensitive to tetracycline. We performed a case-control study among 61 cholera patients and age-, sex-, and clinic-matched controls. Multivariate analysis showed that risk factors for cholera were drinking water from Lake Victoria or from a stream, sharing food with a person with watery diarrhea, and attending funeral feasts. Compared with other diarrheal pathogens, cholera was more common among persons living in a village bordering Lake Victoria. Cholera has become an important public health concern in western Kenya, and may become an endemic pathogen in the region.
Limited genetic diversity of Plasmodium falciparum in field isolates from Honduras.
Authors: Haddad D , Snounou G , Mattei D , Enamorado I G , Figueroa J , StÃ¥hl S , Berzins K
Published: May 2017

The genetic diversity displayed by Plasmodiumfalciparum field isolates, the occurrence of variant forms of the parasite at different frequencies in different geographic areas, and the complexity of the infections represent major obstacles for the development of effective malaria control measures. However, since most of the existing studies have been performed in regions where P. falciparum transmission is high, little is known about the diversity and complexity of parasite populations circulating in areas of low malaria endemicity. We investigated the extent of genetic polymorphism in P. falciparum field isolates from Honduras, a region where its transmission is low and seasonal. Allelic diversity was analyzed in the highly polymorphic parasite genes encoding the merozoite surface proteins- (MSP-1) and -2 (MSP-2) and the glutamate-rich protein (GLURP) by the polymerase chain reaction. Gene polymorphism was also assessed in the EB200 region derived from the highly size polymorphic Pf332 gene. Limited size polymorphism was detected in all genes analyzed, with four and three variants for the MSP-1 and MSP-2 alleles, respectively, and two size variants for the GLURP and Pf332 genes. Moreover, based on the studied genetic markers, most infections consisted of only a few genetically distinct parasite clones. These results suggest that the P. falciparum parasite populations circulating in this region are genetically homogeneous and point to an association between the extent of parasite genetic diversity and the intensity of malaria transmission.
Age-specific decrease in seroprevalence of schistosomiasis in Puerto Rico.
Authors: Hillyer G V , Tsang V C , Vivas-Gonzalez B E , Noh J , Ahn L H , Vorndam V
Published: May 2017

In our previous work, we reported the first systematic, island-wide, serologic survey for schistosomiasis in Puerto Rico in 40 years. In that study, approximately 3,000 serum samples from the 76 municipalities comprising the island of Puerto Rico were tested for the detection of antibodies to S. mansoni microsomal antigens by the Falcon assay screening test-enzyme-linked immunosorbent assay (FAST-ELISA) and those positive were confirmed by an enzyme-linked immunoelectrotransfer blot (EITB). The highest EITB positivity was found in 17 municipalities, which comprised 48% of all seropositive samples. An additional finding was that 10% of the 215 EITB-positive samples were from individuals 25 years or younger and were for the most part of residents from the high seroprevalence areas. Thus, for this study we focused on 766 individuals 25 years of age or younger (45.5% males and 54.4% females), two-thirds of which were from 10 municipalities with the highest EITB seropositivity, and one-third from the 10 municipalities with the lowest EITB seropositivity found in our previous study. Of all samples, the results showed an overall FAST-ELISA positivity of 11.6%, with males similar to females (12.6 versus 10.7%, respectively). Confirmation by EITB was only 1.8%, with a males three-fold higher than females (3% versus 0.7%). When seropositivity was measured by age in five-year increments, a clear age-specific decrease in seropositivity was observed. Thus, by FAST-ELISA, 16.7% of the 21-25-year-old age group was positive, decreasing to 14.6%, 9.9%, 7.9%, and 9.3% in the 16-20-, 11-15-, 6-10-, and 1-5-year-old age groups, respectively. Confirmatory EITB showed even more impressive results: 4.7%, 2.6%, 1.2%, 0.7%, and 0% in the same age brackets. With regard to the high prevalence municipalities, only four of 10 (11 of 228 = 4.8%) had confirmatory EITB-positive samples and most were from municipalities of the Rio Grande de Loiza River basin and tributaries. The male to female positivity ratio was 4:1. Of the low prevalence municipalities, only single positive cases (by EITB) were found in three disperse municipalities. These results support the concept that there has been little transmission of S. mansoni in Puerto Rico during the first half of the 1990s and confirms anecdotal comments of local physicians who have seen virtually no new infections during the past three years. This makes the documentation of eradication of schistosomiasis from Puerto Rico feasible, a goal that should be set as being before the 100th anniversary of its discovery on the island by Isaac Gonzalez-Martinez in 1904.
Decreased lactic acidosis and anemia after transfusion of o-raffinose cross-linked and polymerized hemoglobin in severe murine malaria.
Authors: Freilich D , Branda R , Hacker M , Leach L , Barry B , Ferris S , Hebert J
Published: May 2017

Severe anemia is a major cause of death in falciparum malaria. Blood transfusion increases survival in humans and in animal models of this disease. Because of logistic constraints and viral contamination of the blood supply, transfusions are frequently not practical in endemic regions. Modified hemoglobin is an effective O2 carrier in hemorrhagic shock. It is free of infectious contamination, may not require refrigeration, and because of its nitric oxide scavenging and small size, may have pharmacologic benefits in malaria. The effects of transfusions of modified hemoglobin in rats with high-grade parasitemia were evaluated. Modified hemoglobin decreased lactic acidosis and corrected anemia as well as transfusions with red blood cells; these findings may correlate with improved survival and suggest a possible proerythropoietic effect. Further study of this novel therapy is warranted.
Isolation of thogoto virus (Orthomyxoviridae) from the banded mongoose, Mongos mungo (Herpestidae), in Uganda.
Authors: Ogen-Odoi A , Miller B R , Happ C M , Maupin G O , Burkot T R
Published: May 2017

Small wild vertebrates were trapped during an investigation into possible vertebrate reservoirs of o'nyong-nyong (ONN) fever virus in Uganda in 1997. Antibody neutralization test results and virus isolation attempts were negative for ONN virus, confirming the work of earlier investigators, who also failed to find evidence for a nonhuman ONN virus reservoir. In the course of these ONN virus studies, Thogoto virus was isolated from one of eight banded mongooses (Mongos mungo). This is the first isolation of Thogoto virus from a wild vertebrate. Neutralizing antibodies to Thogoto virus were also found in two of the other mongooses.
A continuing focus of Hansen's disease in Texas.
Authors: Taylor J P , Vitek I , Enriquez V , Smedley J W
Published: May 2017

To describe epidemiologic and clinical characteristics of Hansen's disease cases in Texas, information was abstracted from records of 810 patients reported from 1973 through 1997. Annually, from 18 to 54 patients were reported. Average annual incidence rates ranged from 1.9 to 2.4 cases per million population. A majority of the patients were male (63%) and white (77%). More than half (53%) of the patients were born in the United States; a majority (83%) of the patients born in the United States were born in Texas. Most (76%) patients were diagnosed with multi-bacillary leprosy. Foreign-born patients were more likely to be younger at onset and have multi-bacillary disease compared with patients born in the United States. Within Texas, an endemic focus of Hansen's disease exists along the Gulf of Mexico coast.
Phenotypic and genotypic characteristics of recently adapted isolates of Plasmodium falciparum from Thailand.
Authors: Mungthin M , Bray P G , Ward S A
Published: May 2017

The drug sensitivity characteristics and Plasmodium falciparum pfmdr1 status of five isolates of P. falciparum recently isolated from patients presenting for treatment from the Thailand/Myanmar border have been investigated. The aim of the study was to avoid the criticisms of some earlier studies by focusing on newly collected isolates from a specific geographic location. Three of the isolates studied exhibited clear resistance to chloroquine similar to that observed in the K1 Thai standard isolate obtained in the 1970s, and the other two isolates were of intermediate sensitivity to chloroquine with concentrations of drug that inhibit parasite growth by 50% of 50 and 43 nmol. The sensitivity of all isolates was enhanced by verapamil but we found no clear association between chloroquine sensitivity and gene copy number or intra-allelic variation of pfmdr1. In contrast, clear cross-resistance was seen between mefloquine and halofantrine, with the most sensitive isolates carrying the K1 mutation in pfmdr1.
Pyrimethamine-sulfadoxine efficacy and selection for mutations in Plasmodium falciparum dihydrofolate reductase and dihydropteroate synthase in Mali.
Authors: DiourtÃ© Y , DjimdÃ© A , Doumbo O K , Sagara I , Coulibaly Y , Dicko A , Diallo M , DiakitÃ© M , Cortese J F , Plowe C V
Published: May 2017

To assess pyrimethamine-sulfadoxine (PS) efficacy in Mali, and the role of mutations in Plasmodium falciparum dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) in in vivo PS resistance, 190 patients with uncomplicated P. falciparum malaria were treated with PS and monitored for 56 days. Mutation-specific polymerase chain reactions and digestion with restriction endonucleases were used to detect DHFR and DHPS mutations on filter paper blood samples from pretreatment and post-treatment infections. Only one case each of RI and RII level resistance and no cases of RIII resistance or therapeutic failure were observed. Post-PS treatment infections had significantly higher rates of DHFR mutations at codons 108 and 59. No significant selection for DHPS mutations was seen. Pyrimethamine-sulfadoxine is highly efficacious in Mali, and while the low level of resistance precludes assessing the utility of molecular assays for in vivo PS resistance, rapid selection of DHFR mutations supports their role in PS failure.
Blockage of skin invasion by schistosome cercariae by serine protease inhibitors.
Authors: Lim K C , Sun E , Bahgat M , Bucks D , Guy R , Hinz R S , Cullander C , McKerrow J H
Published: May 2017

Invasion of skin by schistosome cercariae is facilitated by a serine protease secreted from the acetabular cells of cercariae in response to skin lipid. Specific inhibitors of the protease, when applied to human skin in formulations designed to retain the inhibitor on and in the upper stratum corneum layers, block cercarial invasion of human skin. Both peptide-based, irreversible inhibitors and non-peptide, reversible inhibitors block cercarial invasion when applied in a propylene glycol:isopropyl alcohol (3:1) formulation in vitro. Arrest of cercarial invasion could be achieved even after immersion of treated skin in water for 2 hr. Peptide-based irreversible inhibitors in the presence of three different Topicare Delivery Compounds optimized arrest of cercarial invasion. The three Topicare Delivery Compounds applied alone prevented 80-100% of cercarial invasion. With inclusion of the inhibitor, there was 97-100% inhibition in vitro. The optimal formulation with inhibitor was then applied to the tails of BALB/c mice, and the mice were exposed to 120 cercariae by tail immersion. With the carrier lotion alone, there was a 50% reduction in worm burden and a 70% reduction in egg burden. When inhibitor was included, an 80% reduction in worm burden and a 92% reduction in egg burden was observed.
Estimates of gene flow among Anopheles maculatus populations in Thailand using microsatellite analysis.
Authors: Rongnoparut P , Sirichotpakorn N , Rattanarithikul R , Yaicharoen S , Linthicum K J
Published: May 2017

We report an analysis of seven microsatellite loci in eight populations of Anopheles maculatus mosquitoes dispersed over a distance of approximately 1,100 km in Thailand. A wide spectrum of genetic variability, with mean heterozygosities ranging from 0.738 to 0.847 were found. Based on microsatellite analysis, geographic populations of An. maculatus can be grouped into two clusters; one includes upper and lower northern populations that extend from approximately 11 degrees to 16 degrees north latitude, and the other (southern populations) extends south from about 7 degrees to 6 degrees north latitude. Wright's F(ST) and Slatkins's R(ST) for all seven microsatellite loci indicated low estimates of differentiation among all populations (mean values of F(ST) and R(ST) = 0.0406 and 0.051, respectively, corresponding to the Nm values of 5.91 and 4.65, respectively), and suggested that gene flow occurs among populations. However, there is some restriction of gene flow between the northern and southern populations. Geographic barriers could be limiting factors for greater gene flow between populations.
Serologic IgG response to urease in Helicobacter pylori-infected persons from Mexico.
Authors: Leal-Herrera Y , Torres J , Perez-Perez G , Gomez A , Monath T , Tapia-Conyer R , MuÃ±oz O
Published: May 2017

Helicobacter pylori urease is required to counteract acidity during colonization of the stomach, and has been suggested as a major immunodominant antigen. The aim of this study was to determine the anti-urease response in a representative national serologic survey in Mexico. The population surveyed included persons 1-90 years of age from all socioeconomic levels and geographic zones of the country. Helicobacter pylori status was determined by ELISA serology. The IgG anti-urease was studied by ELISA using a recombinant apoenzyme. We found that 2,930 of the 7,720 infected patients (38%) were seropositive for IgG urease. The rate of IgG anti-urease positivity increased with age; in children < 10 years old it was < 20% and in persons > 40 years old it was > 50%. Age and a region with a high level of development were risk factors for seropositivity, whereas gender, educational level, crowding, and socioeconomic level were not associated with seropositivity. In conclusion, in natural infection with H. pylori, the response to urease is poor, mainly during the first years of infection. This inconsistent immune response to the enzyme may favor persistence of infection. A vaccine eliciting a consistent anti-urease response might overcome immune evasion and enhance clearance of bacteria after exposure.
Gender-related efficacy difference to an extended duration formulation of topical N,N-diethyl-m-toluamide (DEET).
Authors: Golenda C F , Solberg V B , Burge R , Gambel J M , Wirtz R A
Published: May 2017

A clinical trial (n = 120, 60 males and 60 females) was conducted to assess the efficacy of an extended duration tropical insect/arthropod repellent (EDTIAR) topical formulation of N,N-diethyl-m-toluamide (DEET). The amount of EDTIAR (mean +/- confidence interval), applied by participants in accordance with label directions, was not significantly different between females (3.66 +/- 0.32 mg/cm2) and males (3.45 +/- 0.33 mg/cm2). There also was no significant difference in the number of Anopheles stephensi mosquitoes biting the control arm of females or males at 0, 3, 6, 9, and 12 hr. While gender had no effect on feeding, the time of day did effect mosquito feeding with fewer mosquitoes feeding in the afternoon than in the morning or evening. The percent protective efficacy at 0, 3, 6, 9, and 12 hr was 100.0, 99.3, 92.8, 79.7 and 66.3 for females, and 100.0, 100.0, 97.6, 91.9, and 77.5 for males. These data are inconsistent with the EDTIAR label claim that the repellent provides 95% or greater protection against mosquitoes for 12 hr or more under normal use conditions. The results of a multivariate regression analysis indicated that 1) protection decreased linearly as time after application of repellent increased (P < 0.001), 2) individuals who applied higher doses of repellent were better protected against mosquito bites (P < 0.001), 3) females experienced significantly less protection over time than did males (P = 0.005), and 4) the estradiol concentration in the blood had no effect on efficacy of the repellent (P = 0.110).
Reactivation of neurocysticercosis: case report.
Authors: Sheth T N , Lee C , Kucharczyk W , Keystone J
Published: May 2017

A 37-year-old woman with a known history of longstanding neurocysticercosis presented with a three-day history of new onset headache. Several years prior to her current presentation, she had undergone cysticidal treatment and was assumed to be cured of active disease. Computed tomography and magnetic resonance imaging studies done three months prior to presentation showed multiple intracerebral calcified lesions consistent with resolved neurocysticercosis. Physical and laboratory findings were noncontributory. Imaging studies showed the same previously calcified lesions, but they were now surrounded by large amounts of edema. This case represents a unique report of reactivation of neurocysticercosis and raises interesting questions about the natural history of this infection.
Role of eicosanoids in the pathogenesis of murine cerebral malaria.
Authors: Xiao L , Patterson P S , Yang C , Lal A A
Published: May 2017

Because microvascular damage is a common feature of cerebral malaria, we have examined the role eicosanoid metabolites (prostaglandins and leukotrienes) in experimental cerebral malaria. Eighty ICR mice were infected with Plasmodium berghei ANKA, with 40 uninfected mice as controls. Half of the infected mice were treated on days 4 and 5 with aspirin, a prostaglandin synthesis inhibitor. Infected mice started to die of cerebral malaria on day 6, and by day 17, all infected mice died. In contrast, all infected mice treated with aspirin died by day 12. Infected mice had increased phospholipase A2 mRNA expression in the spleen and cyclooxygenase 1 (COX1) and COX2 expression in the brain. At the peak of cerebral malaria, infected mice had higher serum leukotriene B4 levels than control mice, and aspirin-treated infected mice had higher serum leukotriene B4 levels than untreated infected mice. These results suggest that prostaglandins are protective whereas leukotrienes are detrimental in cerebral malaria.
Cellular responses to Plasmodium falciparum major surface antigens and their relationship to human activities associated with malaria transmission.
Authors: Carvalho L H , Fontes C J , Krettli A U
Published: May 2017

In Brazil, two types of activities have led to the worsening of malarial transmission in the Amazon region: prospecting/mining and agricultural settlements. In the present study, we analyze the cellular response of 52 of these individuals (14 gold-miners and 38 farmers) living within the same endemic area. Two Plasmodium falciparum major surface antigens (recombinant proteins) were used for cellular proliferative assays: circumsporozoite protein and merozoite surface protein-1. The frequency of these cellular responses were significantly higher among the miners (57-64%) than the farmers (10-20%) when either recombinant protein was used. Our data suggest that a higher exposure to malaria of the gold-miners contributed to their higher in vitro cellular response compared with the farmers. These findings point the way to further studies evaluating the influence of risk factors associated with the life styles of different social groups and the immune responses to these antigens.
A genus- and species-specific nested polymerase chain reaction malaria detection assay for epidemiologic studies.
Authors: Singh B , Bobogare A , Cox-Singh J , Snounou G , Abdullah M S , Rahman H A
Published: May 2017

A nested polymerase chain reaction (PCR) assay that uses Plasmodium genus-specific primers for the initial PCR (nest 1) amplification and either genus- or species-specific primers for the nest 2 amplifications was tested on laboratory and field samples. With in vitro cultured Plasmodium falciparum-infected blood samples, it was capable of detecting six parasites/microl of blood using DNA prepared from 25-microl blood spots on filter paper. The assay was evaluated on fingerprick blood samples collected on filter paper from 129 individuals living in a malaria-endemic area in Malaysia. Malaria prevalence by genus-specific nested PCR was 35.6% (46 of 129) compared with 28.7% (37 of 129) by microscopy. The nested PCR detected seven more malaria samples than microscopy in the first round of microscopic examination, malaria in three microscopically negative samples, six double infections identified as single infections by microscopy and one triple infection identified as a double infection by microscopy. The nested PCR assay described is a sensitive technique for collecting accurate malaria epidemiologic data. When coupled with simple blood spot sampling, it is particularly useful for screening communities in remote regions of the world.
Case-control study of seropositivity for cysticercosis in Cuenca, Ecuador.
Authors: Goodman K A , Ballagh S A , Carpio A
Published: May 2017

The prevalence of neurocysticercosis has been well documented in rural communities in Latin America using the enzyme-linked inmmunoelectrotransfer blot (EITB) assay. We studied the prevalence of neurocysticercosis in an urban, upper-middle class population in Cuenca, Ecuador. Family members of 34 index cases with parenchymal neurocysticercosis on a computed tomography (CT) scan and family members of 14 patients who had normal CT scans after a trauma or migraine were enrolled in the study. Serum was obtained from 226 individuals, 173 (72%) from the case families and 67 (28%) from the control families. Twelve percent of the case family members and 4% of the control family members were seropositive by the EITB assay. This was a statistically significant difference (P < 0.05) when age and education were held constant by logistic regression. Seropositivity was not related to age. No neurologic symptom proved predictive of serostatus and the only demographic variable that correlated with seropositivity was increased crowding. Positive serology in index cases did correlate with CT findings as follows: 86% of patients with active lesions, 67% with transitional lesions, and only 41% of patients with inactive lesions were positive by the EITB assay. Eighteen percent of family members with a positive EITB test result had parenchymal lesions on a subsequent CT scan. This study demonstrates a high rate of seropositivity of cysticercosis among urban, middle to upper-middle class individuals in a region endemic for Taenia solium. Household contacts of patients with neurocysticercosis had a three-fold higher risk of positive serology for cysticercosis, in comparison with controls.
Hantavirus (Bunyaviridae) infections in rodents from Orange and San Diego counties, California.
Authors: Bennett S G , Webb J P , Madon M B , Childs J E , Ksiazek T G , Torrez-Martinez N , Hjelle B
Published: May 2017

During a screening program to determine the extent of hantavirus activity in Orange and San Diego Counties, California, serum samples from 2,365 rodents representing nine genera and 15 species were tested for hantavirus antibodies. A reverse transcription-polymerase chain reaction on selected seropositive rodents was used to identify the specific hantavirus. Rodents positive for Sin Nombre virus (SNV) antibodies by Western blot included 86 (9.1%) of 948 deer mice (Peromyscus maniculatus), four (1.5%) of 275 California mice (Peromyscus californicus), one (0.5%) of 196 cactus mice (Peromyscus eremicus), 51 (12.2%) of 417 harvest mice (Reithrodontomys megalotis), and five (12.5%) of 40 California voles (Microtus californicus). All other specimens tested were negative for hantavirus antibodies. There was a correlation between age and sex of the reservoir host and prevalence of SNV antibody, especially among male deer mice and harvest mice. Few seasonal trends in antibody prevalence were observed and continued maintenance of SNV and El Moro Canyon virus was found at several foci over a 4-5-year period. Isla Vista virus was also found in voles and represents the first recorded in Orange County. Microhabitat selection on the part of these rodents based on plant density, plant height, and availability of food plants may explain, to some extent, all of the hantavirus-positive foci throughout the study area over a broad geographic range and the lack of antibody-positive rodents in dense chaparral, woodland, and riparian areas. The majority of rodents positive for SNV was identified from localities along coastal bluffs and the foothills of the Santa Ana Mountains, where trap success was high and P. maniculatus represented 43% of all rodents collected. Several residential, commercial, and industrial sites exist in these areas and the potential health risk should not be overlooked. This study represents an in-depth analysis of the prevalence, host distribution, and characteristics of rodent populations infected by three hantaviruses within a small, well-defined, geographic area.
Increased postwar symptoms and psychological morbidity among U.S. Navy Gulf War veterans.
Authors: Gray G C , Kaiser K S , Hawksworth A W , Hall F W , Barrett-Connor E
Published: May 2017

To investigate reports on war-related morbidity, 527 active-duty Gulf War veterans and 970 nondeployed veterans from 14 Seabee commands were studied in 1994 with a questionnaire, sera collection, handgrip strength, and pulmonary function testing. The questionnaire assessed postwar symptoms, war exposures, and screened for chronic fatigue syndrome, post-traumatic stress disorder, and psychological symptoms suggesting neurosis (Hopkins Symptom Checklist). Sera were tested with four nonspecific reactant assays: C-reactive protein, transferrin, ferritin, and haptoglobin. Gulf War veterans reported a higher prevalence for 35 of 41 symptoms, scored higher on psychological symptom scales, were more likely to screen for post-traumatic stress disorder, had lower handgrip strength, and had higher serum ferritin assay results. Numerous comparisons of these morbidity outcomes with 30 self-reported exposures demonstrated many associations, but no unique exposure or group of exposures were implicated. Morbidity data are consistent with other postwar observations, but the etiology for morbidity findings remains uncertain.
Survey of Bartonella species infecting intradomicillary animals in the HuayllacallÃ¡n Valley, Ancash, Peru, a region endemic for human bartonellosis.
Authors: Birtles R J , Canales J , Ventosilla P , Alvarez E , Guerra H , Llanos-Cuentas A , Raoult D , Doshi N , Harrison T G
Published: May 2017

The natural cycle of Bartonella bacilliformis remains uncertain, and the suspected existence of animal reservoirs for the bacterium has never been convincingly demonstrated. We conducted a survey of Bartonella species infecting intradomicillary animals in a bartonellosis-endemic region of Peru, obtaining blood from 50 animals living in the homes of 11 families whose children had recently had bartonellosis. Bartonella-like bacteria were recovered from four of nine small rodents included in the study, but from none of the 41 domesticated animals. Identification and comparison of these isolates, and two Bartonella-like isolates obtained from Phyllotis mice in a different endemic region of Peru using serologic and genotypic methods indicated that although none were strains of B. bacilliformis, five were probably representatives of three previously unrecognized Bartonella species and one was a likely strain of the pathogenic species B. elizabethae.