bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative neurovirulence of attenuated and non-attenuated strains of Venezuelan equine encephalitis virus in mice.
Authors: Ludwig G V , Turell M J , Vogel P , Kondig J P , Kell W K , Smith J F , Pratt W D
Published: May 2017

A candidate live-attenuated virus vaccine for protection against Venezuelan equine encephalitis (VEE) (designated V3526) was tested in mice to measure the magnitude, duration, and kinetics of virus replication in the blood and the central nervous system and its phenotypic stability after multiple passages in mice and cell culture. All results were compared to parallel experiments with parental virus and the existing VEE virus vaccine, TC-83. Maximum virus titers in the brains of V3526-inoculated mice were between 10- and 100-fold less than those observed in brains of mice inoculated intracranially (i.c.) with either the parental virus or TC-83. Neither V3526 nor TC-83 was lethal in BALB/c mice inoculated i.c. However, mice inoculated with TC-83 developed acute symptoms lasting at least 14 days. In contrast, i.c. inoculation of TC-83 was uniformly lethal for C3H/HeN mice. V3526 was avirulent in both BALB/c and C3H/HeN mice after i.c. inoculation. The virulence characteristics of V3526 remained unchanged after five serial i.c. passages in mouse brains or after five cell culture passages. Finally, pathologic changes induced after i.c. inoculation of V3526 were consistently less severe and of shorter duration than those observed in TC-83-inoculated mice. Based on these results, V3526 is stable and appears to be significantly less neurovirulent in mice than TC-83.
The dengue and dengue hemorrhagic fever epidemic in Puerto Rico, 1994-1995.
Authors: Rigau-PÃ©rez J G , Vorndam A V , Clark G G
Published: May 2017

From June 1, 1994 to May 31, 1995 a total of 24,700 cases of dengue (7.01/1,000 population) were reported to the laboratory-based surveillance system in Puerto Rico (1991-1994, annual average: 2.55/1,000). Dengue virus 2 predominated. The earliest indicator of epidemic activity was the virus isolation rate in May 1994 (14.0% versus 5.7% average). The male-to-female ratio among cases was 1:1.1; 65.4% were younger than 30 years (the 10 to 19 year age group had the highest incidence, 11.8/1,000). At least 5,687 cases (23.0%) showed a hemorrhagic manifestation; 4,662 (18.9%) were hospitalized, and 40 died (0.2%; 10 laboratory-positive). Two cases documented by laboratory were transmitted by unusual routes--intrapartum and through a bone marrow transplant. Among 2,004 hospitalized cases reported by infection control nurses, 139 (6.9%) fulfilled the criteria for dengue hemorrhagic fever (DHF) and another 13 cases (0.6%) had dengue shock syndrome. This epidemic produced the largest number of hospitalizations, DHF cases, and deaths from any dengue epidemic in Puerto Rico. Severity did not change throughout the year. Surveillance capabilities were maintained by temporary, simplified reporting methods, none of which could be recommended as the single method of choice for surveillance; each must be used (on site, or as a service available from a reference laboratory) at the right time in the epidemic cycle. The utility of comparisons of current and previous data underscores the value of long-term surveillance. Our analysis was unable to document whether significantly increased transmission occurred more often in cities where the water supply was rationed or where the local landfill was closed.
Dengue activity in Puerto Rico during an interepidemic period (1995-1997).
Authors: Rigau-PÃ©rez J G , Ayala-LÃ³pez A , Vorndam A V , Clark G G
Published: May 2017

From 1995 to 1997 dengue was reported in Puerto Rico at an average annual rate of 1.75/1,000 population, compared to 6.73 in 1994, an epidemic year. Dengue virus serotypes 1 (DEN-1), -2, and -4 were isolated each year, with DEN-2 predominating in 1995 and 1996, and DEN-4 in 1997. From 1995 through 1997 incidence was highest (0.61-0.77/1,000) in persons under 30 years of age; males and females were equally affected. Among positive cases, 28.3% to 37.9% were hospitalized; 28.9% to 35.2% had hemorrhagic manifestations; at least 1.1% to 1.6% fulfilled the criteria for dengue hemorrhagic fever/dengue shock syndrome; and 0.2% to 0.3% died. Neither hurricane preparations (1995) nor widespread floods (1996) seem to have affected dengue incidence. Most municipalities with the highest laboratory-diagnosed dengue rates in 1995 were in the eastern foothills of the central mountains, an area relatively spared by the 1994 epidemic. In the next two years, at least half of the municipalities with the highest laboratory-diagnosed dengue rates were in the west. The most intense municipal outbreak of this period (DEN-2, Villalba, 1995, rate of 11.67/1,000) is described to highlight the importance of local conditions and epidemiologic history in determining the risk of dengue.
Longitudinal study of natural immune responses to the Plasmodium falciparum apical membrane antigen (AMA-1) in a holoendemic region of malaria in western Kenya: Asembo Bay Cohort Project VIII.
Authors: Udhayakumar V , Kariuki S , Kolczack M , Girma M , Roberts J M , Oloo A J , Nahlen B L , Lal A A
Published: May 2017

We investigated the development and maintenance of proliferative and antibody responses to apical membrane antigen-1 (AMA-1) epitopes in a holoendemic area of western Kenya. Young children (< 10 years), older children (10-17 years), and adults (> or = 18 years) were followed longitudinally for antibody and T-cell responses at 3 time points with an interval of 3-4 months. The proliferative responses against the AMA-1 T epitopes (PL171, PL172, PL173, PL186, PL191, and PL192) were not stable during follow-up; however, response to mycobacterial antigen PPD was highly stable. The responder frequencies were similar in all 3 time points except for epitope PL192. The younger and older children responded more frequently to T-cell epitopes, but the differences were not significant. A positive proliferative response to PL191 was associated with a significantly lower risk of parasitemia at subsequent follow-up (relative risk, 0.5; P = 0.03). The presence of antibody response to B epitopes PL169, PL170, PL173, PL187, and PL192 in one time point was associated with a subsequent response (P = 0.0001-0.008) suggesting a stable response. Younger (P = 0.046) and older children (P = 0.017) more frequently responded to epitope PL169 than did adults, and adults responded more frequently to PL187 than did younger children (P = 0.009). Responses to AMA-1 T-cell epitopes were short lived, and antibody responses were relatively stable.
The Carter Center's assistance to river blindness control programs: establishing treatment objectives and goals for monitoring ivermectin delivery systems on two continents.
Authors: Richards F O , Miri E S , Katabarwa M , Eyamba A , Sauerbrey M , Zea-Flores G , Korve K , Mathai W , Homeida M A , Mueller I , Hilyer E , Hopkins D R
Published: May 2017

Periodic mass treatment with ivermectin in endemic communities prevents eye and dermal disease due to onchocerciasis. As part of an international global partnership to control onchocerciasis, The Carter Center's Global 2000 River Blindness Program (GRBP) assists the ministries of health in ten countries to distribute ivermectin (Mectizan, donated by Merck & Co.). The GRBP priorities are to maximize ivermectin treatment coverage and related health education and training efforts, and to monitor progress through regular reporting of ivermectin treatments measured against annual treatment objectives and ultimate treatment goals (e.g., full coverage, which is defined as reaching all persons residing in at risk villages who are eligible for treatment). Since the GRBP began in 1996, more than 21.2 million ivermectin treatment encounters have been reported by assisted programs. In 1999, more than 6.6 million eligible persons at risk for onchocerciasis received treatment, which represented 96% of the 1999 annual treatment objective of 6.9 million, and 78% of the ultimate treatment goal in assisted areas.
Short report: characterization of enteroaggregative Escherichia coli isolates from Iranian children.
Authors: Bouzari S , Jafari A , Azizi A , Oloomi M , Nataro J P
Published: May 2017

We have previously shown that enteroaggregative Escherichia coli (EAEC) is an important pathogen among Iranian infants and children. To better understand the characteristics of EAEC in Iran, we analyzed EAEC isolates for the presence of pAA plasmid-borne factors. Ninety-eight E. coli strains that displayed the aggregative adherence (AA) pattern on HeLa cells were hybridized with the CVD432 (AA) probe and with genes encoding enteroaggregative heat-stable enterotoxin-1 and aggregative adherence fimbriae (AAF) I and II. Our data suggest that AAF/II is common in this population and that AAF/I and AAF/II can sometimes be detected in the same E. coli isolate. Surprisingly, we have found that AA probe-negative strains in Iran share virulence factors with AA probe-positive isolates and therefore may be more similar to probe-positive strains than previously believed.
Clinical features of vivax malaria.
Authors: Oh M D , Shin H , Shin D , Kim U , Lee S , Kim N , Choi M H , Chai J Y , Choe K
Published: May 2017

Plasmodium vivax malaria reemerged in the Republic of Korea in 1993 near the Demilitarized Zone (DMZ). We reviewed clinical features of 101 symptomatic patients with vivax malaria. Of the patients, 77 patients (76.3%) were veterans who had served near the DMZ; their median age was 23 years. The duration of the minimum latent period was > 6 months in 66.2% (51 of 77) of the patients (median, 278 days). Tertian fever developed in 69 patients (68.3%). Severe thrombocytopenia with platelet counts < 60,000/microL was common (29.6% of patients). The parasite densities ranged 32-52,127 parasites per microliter of blood (geometric mean, 1,287). The only complication was a splenic rupture in one patient. All patients responded promptly to chloroquine therapy. Our data suggest that the clinical features of reemerging vivax malaria may be similar to those of Korean vivax malaria reported in the past.
Protection of pigs with cysticercosis from further infections after treatment with oxfendazole.
Authors: Gonzalez A E , Gavidia C , Falcon N , Bernal T , Verastegui M , Garcia H H , Gilman R H , Tsang V C , _ _
Published: May 2017

Cysticercosis, the infection by the larvae of Taenia solium, is a major cause of acquired epilepsy in the world; it also causes significant economic loss because of contaminated pork. This disease is endemic in most developing countries and no control strategy has yet been proven efficient and sustainable. To further evaluate the full potential of single-dose oxfendazole treatment for pigs as a control measure, 20 pigs with cysticercosis were treated with oxfendazole and later matched with 41 naive pigs and exposed to a natural challenge in a hyperendemic area. New infections were found by serologic testing in 15 of the 32 controls (47%), and by the presence of cysts at necropsy in 12 of them (37%). Only minute residual scars were detected in the carcasses of oxfendazole-treated pigs. Pigs with cysticercosis, once treated with oxfendazole, are protected from new infections for at least three months.
A cluster of melioidosis cases from an endemic region is clonal and is linked to the water supply using molecular typing of Burkholderia pseudomallei isolates.
Authors: Currie B J , Mayo M , Anstey N M , Donohoe P , Haase A , Kemp D J
Published: May 2017

Nine cases of melioidosis with four deaths occurred over a 28-month period in members of a small remote Aboriginal community in the top end of the Northern Territory of Australia. Typing by pulsed-field gel electrophoresis showed isolates of Burkholderia pseudomallei from six of the cases to be clonal and also identical to an isolate from the community water supply, but not to soil isolates. The clonality of the isolates found in this cluster contrasts with the marked genetic diversity of human and environmental isolates found in this region which is hyperendemic for B. pseudomallei. It is possible that the clonal bacteria persisted and were propagated in biofilm in the water supply system. While the exact mode of transmission to humans and the reasons for cessation of the outbreak remain uncertain, contamination of the unchlorinated community water supply is a likely explanation.
Serious adverse events of mefloquine in relation to blood level and gender.
Authors: Schwartz E , Potasman I , Rotenberg M , Almog S , Sadetzki S
Published: May 2017

Mefloquine is widely used for prophylaxis in areas with chloroquine-resistant falciparum malaria. As the use of mefloquine has increased, so have the reports on its adverse effects. We sought to evaluate the possible association between serum levels of mefloquine and serious side effects caused by this drug by means of a case-control design study. The study population included 17 patients who presented to emergency rooms or travel clinics with symptoms suggesting serious adverse effects of mefloquine and 28 controls (healthy people, still taking mefloquine after travel). The mean age of the patients and the controls was 31.5 +/- 11.6 years and 34 +/- 12.2 years, respectively. The percentage of women among the patients was higher than in the control population (76% versus 40%, respectively; P = 0.03). Most of the complaints were related to the central nervous system (13 of 17); 5 patients interrupted their trip and 2 others were hospitalized. No difference in the level of mefloquine in the blood was found between the patients and the control groups. Also, no significant difference was found between mefloquine levels in the blood of men and women. These results suggest that blood levels of mefloquine do not correlate with its severe adverse events. Women tended to be more susceptible than men, despite having similar blood levels of the drug.
Short report: floxacrine analog WR 243251 inhibits hematin polymerization.
Authors: Dorn A , Scovill J P , Ellis W Y , Matile H , Ridley R G , Vennerstrom J L
Published: May 2017

Floxacrine was a promising antimalarial compound that led to the identification of WR 243251. On the basis of their structures, we suspected that these compounds might be good inhibitors of hematin polymerization. Indeed, WR 243251 was as potent and floxacrine was only 2-fold less potent than chloroquine as inhibitors of this process. However, this hematin polymerization inhibition did not completely account for the increased antimalarial potency of WR 243251 versus chloroquine. The WR 243251 ketone hydrolysis product WR 243246 was without activity against hematin polymerization. These data also confirm that hematin polymerization inhibition can be quite sensitive to small changes in inhibitor structure.
Lymphatic filariasis in children: adenopathy and its evolution in two young girls.
Authors: Dreyer G , Figueredo-Silva J , Carvalho K , Amaral F , Ottesen E A
Published: May 2017

Lymphatic filariasis is a widespread infectious disease of children in endemic areas, but little is known about the early lymphatic damage in children and its evolution, either with or without treatment. Two girls (ages 6 and 12 years) from a Wuchereria bancrofti endemic region of Brazil presented with chronic inguinal adenopathy. Neither had microfilaremia. By ultrasound both were shown to have living adult worms in their enlarged inguinal nodes and had occult local lymphatic damage (lymphangiectasis). One girl spontaneously developed acute adenitis in the affected node prior to any intervention; this adenitis resolved within 10 days and was associated with the progressive disappearance over 45-90 days of all local abnormalities detectable by ultrasound. In the other child, after treatment with a single dose of diethylcarbamazine (DEC), the same clinical picture of transient adenitis and resolving abnormalities (detectable by ultrasound) occurred. These findings demonstrated filariasis as the cause of adenopathy in children, and also both spontaneous and treatment-induced worm-death, with subsequent reversal of lymphatic abnormalities.
Diagnosis of genital cervical schistosomiasis: comparison of cytological, histopathological and parasitological examination.
Authors: Poggensee G , Sahebali S , Van Marck E , Swai B , Krantz I , Feldmeier H
Published: May 2017

Granulomatous inflammation of the cervix uteri is a common manifestation of infection with Schistosoma haematobium. In women the cervix is the most common site of infection by S. haematobium. Three methods were used to assess the performance of three different ways of detecting schistosome eggs in cervical tissue: cytological examination of a cervical smear, histological examination of a cervical biopsy, and direct examination of cervical tissue obtained by forceps biopsy (quantitative compressed biopsy technique [QCBT]). Of 228 women studied who lived in an S. haematobium endemic area in Tanzania, 112 (49%) had schistosome eggs detected in the cervix using QCBT. Histological examination detected eggs in 40 of 228 (18%). The cytological examination of cervical smears yielded only 6 positive results (3%). The median egg load in the cervical tissue of cases correctly diagnosed by histology was significantly higher than the egg load in the misclassified cases, indicating that the sensitivity of histological sectioning increases with egg density. We conclude that the QCBT is the diagnostic test of choice for schistosomiasis of the genital cervix.
Capture enzyme-linked immunosorbent assay to detect specific immunoglobulin E in sera of patients with paracoccidioidomycosis.
Authors: Mamoni R L , Rossi C L , Camargo Z P , Blotta M H
Published: May 2017

Paracoccidioidomycosis (PCM) is the most frequent systemic mycosis in South America. The disease is characterized by a polyclonal activation of B cells, resulting in hyperimmunoglobulinemia. The production of immunoglobulin (Ig) E in deep mycosis has been related to the severity of the disease. However, the detection of specific IgE in sera of patients is difficult because of the competition with the IgG. We compared a capture and an indirect enzyme-linked immunosorbent assay (ELISA) technique to detect Paracoccidioides brasiliensis IgE. We found that the capture ELISA presented higher performance and lower background values than the indirect assay, resulting in a significant quantitative discrimination between sera from patients with the 2 major clinical forms of PCM. Patients with the juvenile form presented significantly higher levels of P. brasiliensis IgE, as compared with patients with the adult form. The capture ELISA was used in the follow-up of patients receiving treatment, showing that the levels of specific IgE decreased as the patient's clinical conditions improved.
Phylogenetic analysis of Japanese encephalitis virus: envelope gene based analysis reveals a fifth genotype, geographic clustering, and multiple introductions of the virus into the Indian subcontinent.
Authors: Uchil P D , Satchidanandam V
Published: May 2017

We report the analysis of the complete nucleotide sequence for the Indian isolate (P20778; Genbank Accession number AF080251) of Japanese encephalitis virus (JEV). The phylogenetic tree topology obtained using thirteen complete genome sequences of JEV was reproduced with the envelope, NS1, NS3, and NS5 genes and revealed extensive divergence between the two Indian strains included. A more exhaustive analysis of JEV evolution using 107 envelope sequences available for isolates from different geographic locations worldwide revealed five distinct genotypes of JEV, displaying a minimum nucleotide divergence of 7% with high bootstrap support values. The tree also revealed overall clustering of strains based on geographic location, as well as multiple introductions of JEV into the Indian subcontinent. Nonsynonymous nucleotide divergence rates of the envelope gene estimated that the ancestor common to all JEV genotypes arose within the last three hundred years.
Health risk behaviors and health perceptions in the Peruvian Amazon.
Authors: Nawaz H , Rahman M A , Graham D , Katz D L , Jekel J F
Published: May 2017

Behavioral health risk factor and health belief data for the indigenous population of the Peruvian Amazon are unavailable. Therefore, we conducted structured interviews of adults living in 5 towns in the remote Amazon region of Peru. Respondents (n = 179) were 67% women with a mean age of 35.4 years. The average household size was 6.7 people. A majority (72%) were unable to see a doctor when needed because of lack of money and distance. Only 6% reported excellent health, and nearly half (49%) reported fair health. Forty-eight percent drank alcohol and 73% smoked. Only 34% thought mosquitoes cause malaria, but 98% were using mosquito nets. In conclusion, our findings indicate the indigenous population of the Peruvian Amazon has limited access to basic health care. Although most of those surveyed use mosquito netting, few know that mosquitoes transmit malaria. Tobacco and alcohol use are major behavioral health risk factors.
Persistent infection in Neotoma fuscipes (Muridae: Sigmodontinae) with Ehrlichia phagocytophila sensu lato.
Authors: Castro M B , Nicholson W L , Kramer V L , Childs J E
Published: May 2017

Dusky-footed wood rats (Neotoma fuscipes Baird) and two species of Peromyscus mice (P. maniculatus Wagner and P. truei Shufeldt) were collected over a 16-month period from three sites in Sonoma County, California. Blood was collected from 93 wood rats and 177 mice and serum or plasma was tested for seroreactivity with Ehrlichia phagocytophila sensu lato (also known as the human granulocytic ehrlichiosis agent). Thirty-five (37.6%) wood rats and 15 (8.5%) mice were seropositive. Positive Neotoma serology by site ranged from 9.4% to 62.1%. Polymerase chain reaction (PCR) testing for the Ehrlichia groESL heat shock operon was performed on all the seropositive and selected seronegative wood rats; 24 (68.6%) seropositive animals were PCR positive. Two seroconversions and no seroreversions were detected among 18 of the seropositive wood rats that were recaptured and tested multiple times (range = 2-6). Fourteen (77.8%) of the 18 were also PCR positive with six of these positive at every testing point (range = 2-6). One wood rat remained serologically and PCR positive in six specimens collected over a 14-month period. One male of 84 questing adult Ixodes pacificus Cooley & Kohls collected was PCR-positive for E. phagocytophila. Borrelia burgdorferi, the agent of Lyme disease, was cultured from ear punch biopsies from six of seven E. phagocytophila seropositive and one of four seronegative wood rats.
Household epidemiology of Entamoeba histolytica infection in an urban community in northeastern Brazil.
Authors: Braga L L , Gomes M L , Da Silva M W , FaÃ§anha F E , Fiuza L , Mann B J
Published: May 2017

The natural history of infection with Entamoeba histolytica was studied in 2 slum communities in northeastern Brazil. Twenty-eight index patients colonized with E. histolytica were identified. Three stool specimens from the index patients and their household contacts were gathered over a 45-day period and tested for E. histolytica by means of a specific enzyme-linked immunosorbent assay-based detection kit. The detection kit is an antigen capture assay that has been shown to be highly specific for E. histolytica and does not detect nonpathogenic Entamoeba dispar or other enteric organisms. Blood samples were also collected at the start of the study, at 45 days, and at 6 months and analyzed for E. histolytica-specific antibody. High rates of colonization were seen in the family units. Colonization was self-limited, with 85% of colonized patients clearing their infections within 45 days. Reinfection appeared to be low during this time; however, previous seropositivity did not prevent colonization.
Safety of the insect repellent N,N-diethyl-M-toluamide (DEET) in pregnancy.
Authors: McGready R , Hamilton K A , Simpson J A , Cho T , Luxemburger C , Edwards R , Looareesuwan S , White N J , Nosten F , Lindsay S W
Published: May 2017

The safety of daily application of N, N-diethyl-m-toluamide (DEET) (1.7 g of DEET/day) in the second and third trimesters of pregnancy was assessed as part of a double-blind, randomized, therapeutic trial of insect repellents for the prevention of malaria in pregnancy (n = 897). No adverse neurologic, gastrointestinal, or dermatologic effects were observed for women who applied a median total dose of 214.2 g of DEET per pregnancy (range = 0-345.1 g). DEET crossed the placenta and was detected in 8% (95% confidence interval = 2.6-18.2) of cord blood samples from a randomly selected subgroup of DEET users (n = 50). No adverse effects on survival, growth, or development at birth, or at one year, were found. This is the first study to document the safety of DEET applied regularly in the second and third trimesters of pregnancy. The results suggest that the risk of DEET accumulating in the fetus is low and that DEET is safe to use in later pregnancy.
Short report: Schistosoma mansoni miracidia are killed by the defense system of an Argentine strain of Biomphalaria straminea.
Authors: Grassi L , Torr es JordÃ¡ M , Andrade Z , GonzÃ¡lez Cappa S M
Published: May 2017

Biomphalaria straminea snails from Argentina fail to shed cercariae even if exposed to high doses of Schistosoma mansoni EC miracidia. Alternative explanations for this failure are that miracidia are unable to penetrate the snail's epithelium or that the miracidia are killed by the snail's defense system. To discriminate between these 2 possibilities, B. straminea snails were individually exposed to increasing doses of miracidia. Susceptible B. glabrata were used as controls. Exposed snails were fixed 12 hr after exposure, and histological sections of the whole specimens were examined. Miracidia were seen to penetrate the epithelium of B. straminea and B. glabrata at similar rates (14.7%), independent of the exposure level. Regardless of the miracidial dose, 94% of the penetrating miracidia appeared encapsulated by the B. straminea defense system, whereas in B. glabrata, only 42% of the miracidia underwent encapsulation. These results show that resistance of B. straminea to S. mansoni EC strain is due to an efficient defense system that destroys miracidia once they have penetrated.
Sand fly feeding on noxious plants: a potential method for the control of leishmaniasis.
Authors: Schlein Y , Jacobson R L , MÃ¼ller G C
Published: May 2017

The sand fly Phlebotomus papatasi transmits Leishmania major, which causes cutaneous leishmaniasis, in vast regions of the Old World. In addition to blood, the sand flies feed on plants. In a study of this diet, we observed that one night of feeding on branches of Solanum jasminoides, Ricinus communis, or Bougainvillea glabra drastically shortened the life span of the sand flies. Flowering B. glabra attracted P. papatasi in the field. Nevertheless, in the region endemic for L. major in yards abounding with vector sand flies, the number of P. papatasi trapped near hedges of B. glabra was eight times less (62 versus 502 flies trapped) than in the control sites. The results imply that B. glabra affords local protection against sand fly bites and decreases the risk of leishmaniasis. We suggest that this and other ornamental plants that are harmful to sand flies can be used as a tool for this purpose.
Fatal human melioidosis acquired in a subtropical Australian city.
Authors: Munckhof W J , Mayo M J , Scott I , Currie B J
Published: May 2017

We describe an acute fatal human case of melioidosis acquired in Ipswich, a city at 27.5 degrees S in southern Queensland, south of the area traditionally considered endemic for melioidosis in Australia. Molecular typing revealed that this patient isolate was genetically distinct from 2 other human and 1 bovine isolates of Burkholderia pseudomallei from the same region and from 4 tropical northern Australian strains. This finding suggests that if B. pseudomallei has been introduced to the region from northern Australia, it was not in recent times, and there has not been a point source of infection. Burkholderia pseudomallei is present in temperate southern Queensland, which hitherto has not been well appreciated. Clinicians should consider the diagnosis of acute melioidosis in patients with severe pneumonia or septicemia acquired in subtropical areas such as southern Queensland, particularly after heavy summer rains with flooding.
Longitudinal studies of Sin Nombre virus in deer mouse-dominated ecosystems of Montana.
Authors: Douglass R J , Wilson T , Semmens W J , Zanto S N , Bond C W , Van Horn R C , Mills J N
Published: May 2017

Sin Nombre virus (SNV), hosted by the deer mouse (Peromyscus maniculatus), is the primary etiologic agent of Hantavirus pulmonary syndrome (HPS) in North America. To improve our understanding of the epidemiology of HPS in the western United States, we conducted studies of population dynamics and SNV antibody prevalence in deer mouse populations for 6 years on 12 mark-recapture grids in Montana. Monthly numbers of deer mice ranged from zero to over 170 on 1-hectare grids. SNV antibody prevalence was higher than observed in studies in other parts of the United States, averaging 13% (0% to 50%), and peaking in May or June each year. Antibody-positive mice were older (heavier) (78% of positives were adults versus 52% of negatives) and more likely to be males (61% of positives versus 53.4% of negatives). A higher proportion of antibody-positive deer mice of all age-mass classes had scars than did antibody-negative mice. Month-to-month survivorship of antibody-positive adult mice was similar to that of antibody-negative mice, but survival of young antibody-positive deer mice was lower than antibody-negative deer mice. This is the first study to clearly suggest a detrimental effect of SNV infection on deer mice.
Cystic echinococcosis of the tongue leading to diagnosis of multiple localizations.
Authors: Saez J , Pinto P , Apt W , Zulantay I
Published: May 2017

The tongue is a rare site of localization of cystic echinococcosis. We report a 3-year-old patient with cystic echinococcosis of the tongue demonstrated by histopathology. The cyst of the tongue was surgically removed. The tongue lesion led us to find additional liver and lung cystic lesions that were successfully treated with albendazole therapy.
Cyclospora cayetanensis infections among diarrheal patients from Venezuela.
Authors: ChacÃ­n-Bonilla L , EstÃ©vez J , Monsalve F , Quijada L
Published: May 2017

The prevalence and importance of Cyclospora cayetanensis as an enteropathogen among 71 patients (22-45 years old) with acquired immunodeficiency syndrome (AIDS) and 132 children with diarrhea (0-12 years old) from Venezuela was assessed retrospectively. Two to three stool samples from each patient attending our parasitology laboratory for parasitologic and medical assistance were examined. For identification of the coccidium, modified Ziehl-Neelsen carbolfuchsin staining of formalin-ether stool concentrates was used, and for other intestinal parasites, iron-hematoxylin-stained smears and formalin-ether concentrates were examined. Cyclospora oocysts were found in seven (9.8%) of 71 AIDS patients and seven (5.3%) of 132 children with diarrhea. Other pathogenic parasites were present in most of the patients (9 of 14, 64.3%) shedding oocysts. Cyclosporiasis predominated in children 2-5 years of age with respect to those < or = one year of age (P < 0.05). The findings suggest that C. cayetanensis is common in diarrheal patients from Venezuela. However, the role of the parasite as the causal agent of diarrhea in these patients is uncertain.
Analysis of the peripheral immune response in patients with neurocysticercosis: evidence for T cell reactivity to parasite glycoprotein and vesicular fluid antigens.
Authors: Restrepo B I , Aguilar M I , Melby P C , Teale J M
Published: May 2017

In neurocysticercosis (NCC), it is thought that the long-term survival of the parasite within the human brain is due in part to the ability of the cestode to suppress the local immune response. When the parasite dies, the immunosuppression is apparently lost and a strong local inflammatory response then develops. In contrast, little is known about the immunologic response that may occur in the peripheral immune system of these patients. In this study, the status of the peripheral (extracerebral) cellular and humoral response was evaluated in patients with a history of NCC. The in vitro proliferation of peripheral blood mononuclear cells to mitogens and foreign antigens was similar in patients and controls. Importantly, a substantive response was elicited by two Taenia solium metacestode antigens. In addition, 8 of 10 patients had a detectable humoral response to the antigenic glycoproteins of the cestode. Considering both the cellular and humoral response, all of the patients with NCC presented an active peripheral immunity.
Identification of protective components of two major outer membrane proteins of spotted fever group Rickettsiae.
Authors: DÃ­az-Montero C M , Feng H M , Crocquet-Valdes P A , Walker D H
Published: May 2017

Fragments representing the genes of the two major outer membrane proteins of spotted fever group rickettsiae (rOmpA and rOmpB) were tested as DNA vaccines. Immunizations with each of three fragments (rompA4999-6710, rompB1550-2738, and rompB2459-4123) conferred a degree of protection on vaccinated mice against virulent rickettsial challenge. Protection was achieved when DNA immunizations were followed by booster immunizations with the homologous recombinant protein. Proliferation and gamma-interferon secretion were detected after in vitro stimulation of lymphocytes from immunized animals with whole Rickettsia conorii antigen. The data validate particular segments of rOmpA and rOmpB as potent immunogens and hence as sources of immunostimulatory elements with specificity for T lymphocytes, which are the key effectors of protective immunity against rickettsial infections.
Short report: genetic heterogeneity of Japanese encephalitis virus assessed via analysis of the full-length genome sequence of a Korean isolate.
Authors: Nam J H , Chae S L , Won S Y , Kim E J , Yoon K S , Kim B I , Jeong Y S , Cho H W
Published: May 2017

We determined the full-length genome sequence of Japanese encephalitis virus (JEV) K94P05 isolated in Korea. Sequence analysis showed that the 10,963-nucleotide-long RNA genome of K94P05 was 13 or 14 nucleotides shorter than the genome of other JEV isolates because of a deletion in the 3' noncoding region of K94P05. Compared with sequences of other JEV isolates, the full-length nucleotide sequence showed 89.0-89.6% homology, and the deduced amino acid sequence showed between 96.4-97.3% homology. A region of approximately 60 nucleotides immediately downstream of the open reading frame stop codon of K94P05 showed high sequence variability as compared with other JEV isolates. K94P05 formed a distinct group within a phylogenetic tree established with the full-length genome sequences. Cross-neutralization studies showed that polyclonal antibodies to Korean isolates were 3 times better at neutralizing the Korean isolates than antibodies to Nakayama-NIH. These findings suggest that Korean JEV K94P05 is genetically and antigenically distinct from other Asian JEV isolates.
Distinguishing Plasmodium falciparum treatment failures from re-infections by using polymerase chain reaction genotyping in a holoendemic area in northeastern Tanzania.
Authors: Magesa S M , Mdira K Y , Farnert A , Simonsen P E , Bygbjerg I C , Jakobsen P H
Published: May 2017

An in vivo drug sensitivity study was conducted in Magoda village in northeastern Tanzania to evaluate the usefulness of polymerase chain reaction (PCR)-based genotyping of Plasmodium falciparum parasites to distinguish between re-infection and treatment failure. The study tested P. falciparum susceptibility to a combination of sulfadoxine/pyrimethamine (Fansidar; F. Hoffmann La Roche, Basel, Switzerland). Blood samples were collected before treatment and on days 7, 14, or 28 post-treatment in 51 asymptomatic children, of which 26 could not clear parasitemia within seven days post-treatment. Among the remaining 25 children who had no detectable parasites on day 7, only five remained parasite negative up to day 28. Primary and recrudescent P. falciparum parasites were analyzed by PCR using family specific primers for merozoite surface protein-1 (MSP-1), MSP-2, and glutamate-rich protein (GLURP). All samples contained multiple P. falciparum infections. For all children with recrudescent P. falciparum, common alleles were detected in both the primary and recrudescent samples. However, in no child were the exact same alleles detected in both samples, indicating that probably at least some of the recrudescing parasites originated from new infections. The study demonstrates the general usefulness of PCR genotyping technique in distinguishing re-infections from true recrudescences following therapeutic drug treatment.
Urinary schistosomiasis in southern Ghana: a logistic regression approach to data from a community-based integrated control program.
Authors: Nsowah-Nuamah N N , Mensah G , Aryeetey M E , Wagatsuma Y , Bentil G
Published: May 2017

The data for this analysis are based on the schistosomiasis control project of the Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana, designed to study the feasibility and effectiveness of an integrated schistosomiasis control program. It embraced chemotherapy and health education for community motivation. The study was carried out from 1993 to 1997. This paper presents observations made 24 months after intervention. Eight communities in southern Ghana were grouped into three areas. Individuals in all the areas received praziquantel after the baseline data collection in 1992-1993. Area 1 had passive while Area 3 received active health education. Area 2 received no education. Prevalence of schistosomiasis was the response variable of interest while age, sex, and area were considered as possible influencing variables. The model for the baseline data indicated no significant difference in prevalence among the three areas. The model 24 months after intervention indicated a significant difference among the three areas, suggesting a possible influence of the health education that motivated community participation in the provision of facilities for the control of schistosomiasis.
Worm burden and host responsiveness in Wuchereria bancrofti infection: use of antigen detection to refine earlier assessments from the South Pacific.
Authors: Steel C , Ottesen E A , Weller P F , Nutman T B
Published: May 2017

A population from the Wuchereria bancrofti-endemic island of Mauke was reevaluated retrospectively by use of the Og4C3 circulating antigen (CAg) enzyme-linked immunosorbent assay to assess active infection in relation to host responses by age and gender. Use of microfilaremia (Mf) alone misclassified approximately 50% of infected people, although CAg and Mf levels were positively correlated. Levels of CAg peaked between those aged 31-60 years; men aged > 60 years had a significantly higher CAg prevalence (> 90%) than women. Filaria-specific immunoglobulin (Ig) G4 reached maximum levels in both genders at age 51-60 years. By analysis of variance, both age and gender significantly influenced CAg and IgG4, with men having higher levels of both in the total population. Individuals positive for CAg had significantly lower lymphocyte proliferation responses to parasite antigen than did CAg-negative people, regardless of clinical status. This study reemphasizes the importance of CAg measurements for accurately assessing filarial prevalence and clinical status and demonstrates the relationship between active infection and immune responsiveness.
African-European differences in the capacity of T-cell cytokine production.
Authors: Wilfing A , Winkler S , Schrattbauer K , Willheim M , Baier K , Aichelburg A , MÃ¼ller T , Graninger W , Kremsner P G
Published: May 2017

Regional differences in immune responsiveness have been studied by comparing the frequency of cytokine producing T cells in healthy African children and adults and their age-matched European counterparts. By use of flow cytometry for the intracellular detection of cytokines an overall expansion of CD4+ and CD8+ T cells producing the Type 1 cytokines interleukin (IL)-2 and interferon (IFN)-gamma was observed in adults when compared with children, giving credit to the cumulative effect of contacts with environmental antigens. The CD4+ cells expressing the Type 2 cytokines IL-4 and IL-13, however, increased only in Africans, probably reflecting continuously present challenges with antigens that preferentially drive Type 2 responses. A striking increased frequency of both Type 1 and Type 2 cytokines producing T cells was found in African adults when compared with their European counterparts. The quantitative and qualitative regional differences in immune reactivity are likely to be of significance for all immune intervention strategies, especially for the design of vaccines.
Short report: Thai tick typhus, Rickettsia honei, and a unique rickettsia detected in Ixodes granulatus (Ixodidae: Acari) from Thailand.
Authors: Kollars T M , Tippayachai B , Bodhidatta D
Published: May 2017

A unique Rickettsia species (Rickettsia thailandii sp. nov.) was identified in an Ixodes granulatus by use of polymerase chain reaction heteroduplex mobility assay by use of segments of the citrate synthase gene. This tick was collected from Rattus rattus from Nakhon Ratchasima province in 1970. Another I. granulatus was infected with Thai tick typhus strain TT-118, Rickettsia honei sp. nov. Stenos, Roux, Walker & Raoult; this tick was removed from a R. rattus collected 4 years later from the same province. Ixodes granulatus is the first tick species in Australasia shown to be infected with R. honei and the unique Rickettsia species.
Evaluation of a two-test serodiagnostic method for community assessment of Lyme disease in an endemic area.
Authors: Trevejo R T , Krause P J , Schriefer M E , Dennis D T
Published: May 2017

Epidemiological methods are needed to evaluate community exposure to Borrelia burgdorferi, the causative agent of Lyme disease (LD). For LD serodiagnosis, the Centers for Disease Control and Prevention (CDC) recommends a 2-test approach that involves enzyme immunoassay (EIA) testing and Western immunoblotting (WB) of EIA-equivocal and EIA-positive specimens. The specificity of this approach was evaluated among residents of a LD-endemic community and was compared with WB alone and with a simplified 2-test approach (WB of equivocal EIA only). Participants reporting no previous diagnosis of LD were recruited during a community-wide serosurvey on Block Island, Rhode Island. Of 80 eligible participants, 20 had received LD vaccine. Seven (35%) of 20 vaccinees and 22 (37%) of 60 nonvaccinees reported nonspecific symptoms compatible with LD in the previous year. In this highly LD-endemic community, the overall specificity of the CDC-recommended approach was highest (100%), followed by WB alone (98.7%), then the simplified approach (95%).
Sex differences in immune responses and viral shedding following Seoul virus infection in Norway rats.
Authors: Klein S L , Bird B H , Glass G E
Published: May 2017

In the field, male rodents are more frequently infected with hantaviruses than females. This study examined whether patterns of immune responses against hantavirus differed between the sexes. Male and female Long Evans rats (Rattus norvegicus) were inoculated with Seoul virus, and antibody and cytokine responses, as well as virus shedding were assessed. Males were more likely to shed virus in saliva, to shed virus through multiple routes (saliva, urine, and feces), and to have viral RNA in the spleen than females. Anti-Seoul virus IgG responses were higher in males than females. In both sexes, splenic IFNgamma and IL-4 production increased following infection. After infection, males had higher Th1 immune responses (i.e., IgG2a, IFNgamma, and IL-2) than females; in contrast, Th2 immune responses (i.e., IgG1, IL-4, and IL-10) were similar between the sexes. These data suggest that immune responses to Seoul virus differ between the sexes.
Rapid diagnosis of leishmaniasis by fluorogenic polymerase chain reaction.
Authors: Wortmann G , Sweeney C , Houng H S , Aronson N , Stiteler J , Jackson J , Ockenhouse C
Published: May 2017

A fluorescent DNA probe (LEIS.P1) specific for a conserved region of the small-subunit ribosomal RNA gene of Leishmania and a pair of flanking primers (LEIS.U1 and LEIS.L1) were designed for use in a fluorogenic polymerase chain reaction. Optimal assay conditions with zero background were established to detect low levels of Leishmania from clinical samples. By use of this assay, we amplified DNA from 27 strains of cultured Leishmania (both Old and New World strains) and selectively amplified Leishmania DNA from 12 paraffin-embedded human biopsy samples and 3 fresh human skin biopsy specimens. For the fresh human tissue biopsies, the turnaround time from biopsy to test result was < 24 hr. No amplification was detected in negative control samples (including the kinetoplastid protozoa Trypanosoma rangelli and Crithidia fasiculata). This assay provides a specific and rapid diagnostic modality to detect infection with Leishmania.
Detection of histidine rich protein 2 and panmalarial ICT Malaria Pf/Pv test antigens after chloroquine treatment of uncomplicated falciparum malaria does not reliably predict treatment outcome in eastern Indonesia.
Authors: Tjitra E , Suprianto S , Dyer M E , Currie B J , Anstey N M
Published: May 2017

In regions with drug-resistant malaria, the ability to rapidly detect or predict treatment failure (TF) soon after a course of standard therapy for Plasmodium falciparum malaria would facilitate the prompt institution of second-line therapy. We thus evaluated longitudinally the ability of the ICT Malaria Pf/Pv immunochromatographic test to predict treatment outcome. Sixty-six Sumbanese Indonesians with uncomplicated falciparum malaria were treated with chloroquine and followed for 28 days by use of 1997 World Health Organization criteria for assessment of therapeutic efficacy of antimalarial drugs. The ICT Pf/Pv testing could be compared with microscopy in approximately half of the patients on each day of follow-up. Although strongly positive histidine rich protein 2 (HRP2) line intensities (equal to or greater than the control band) in convalescence were highly predictive of TF, any degree of positivity for the HRP2 and panmalarial antigens in convalescence was only moderately predictive of TE Positive predictive values of the HRP2 and panmalarial antigens for TF were 76.9% and 87.0%, respectively, on Day 3, 82.4% and 87.5% on Day 7, and 78.9% and 78.9% on Day 14. Negative HRP2 and panmalarial antigen results in convalescence were even less predictive of an adequate clinical response, and false-negative HRP2 and panmalarial antigen test results were found in one-sixth (6 of 37) of recrudescent infections diagnosed by microscopy among patients with late treatment failure. To reliably predict treatment outcome with rapid antigen tests, further development appears necessary to improve sensitivity for viable asexual parasites while avoiding detection of both gametocytes and persistent antigen in convalescence.