bluuebunny/crossref_metadata_2025 huggingface dataset:
CROSS-SECTIONAL SEROSURVEY OF FELINE LEISHMANIASIS IN ECOREGIONS AROUND THE NORTHWESTERN MEDITERRANEAN
Authors: SOLANO-GALLEGO LAIA , RODRÍGUEZ-CORTÉS ALHELÍ , INIESTA LAURA , QUINTANA JOSEFINA , PASTOR JOSEPH , ESPADA YVONNE , PORTÚS MONTSERRAT , ALBEROLA JORDI
Published: September 2018

A cross-sectional serosurvey using Leishmania infantum ELISA was performed on 445 cats living in ecoregions around the Northwestern Mediterranean basin; 58 cats from an area of the US where leishmaniasis is not endemic were used as negative controls. ELISA results were further confirmed in 69 cats by Western blot (WB). Finally, 76 of them were also tested for FeLV and FIV. Seroprevalence by ELISA-prot A was 6.29%, and that by ELISA-IgG was 5.25%. Positive cat sera recognized patterns of polypeptides in WB, including L. infantum-specific antigenic fractions. There was no association with retroviruses. Leishmania-specific antibodies are prevalent in cats living in ecoregions around the Northwestern Mediterranean basin; thus, leishmaniasis must be included in the differential diagnosis of diseases in cats living in these ecoregions. Their role as peridomestic reservoirs for L. infantum needs further characterization, but it could be hypothesized that the cat is a secondary reservoir host, rather than an accidental one.
UTILITY OF LYMPH NODE ASPIRATION IN THE DIAGNOSIS OF VISCERAL LEISHMANIASIS IN SUDAN
Authors: BABIKER ZAHIR O. E. , DAVIDSON ROBERT , MAZINDA CHARLES , KIPNGETICH SAMMY , RITMEIJER KOERT
Published: September 2018

We evaluated lymph node aspiration (LNA) as a simple diagnostic procedure for visceral leishmaniasis (VL). Lymph node aspiration was compared with the direct agglutination test (DAT) using a diagnostic titer ≥ 1:6,400 in 7,880 suspected VL patients in eastern Sudan. Compared with DAT, LNA had a sensitivity of 65.1% (95% confidence interval = 63.5–66.6%). Parasite density in LNA correlated strongly with DAT titers (P < 0.0001), and low parasite density accounted for 78.1% of positive LNA results with DAT titers < 1:6,400 (n = 782). Risk factors predictive of a positive LNA result were an age of 1–29 years, male sex, a hemoglobin level < 10.0 g/dL, a DAT titer ≥ 1:800, and a location with a higher prevalence of VL. Lymph node and splenic aspirations were similarly accurate as tests of cure after treatment of 50 VL patients in southern Sudan. Pre-treatment LNA results were negative in 20 cases of severe post kala-azar dermal leishmaniasis.
EVALUATION OF BRUCELLOSIS BY PCR AND PERSISTENCE AFTER TREATMENT IN PATIENTS RETURNING TO THE HOSPITAL FOR FOLLOW-UP
Authors: MAAS KATHLÈNE S. J. S. M. , MÉNDEZ MELISSA , ZAVALETA MILAGROS , MANRIQUE JENNIE , FRANCO MARÍA PÍA , MULDER MAXIMILIAN , BONIFACIO NILO , CASTAÑEDA MARIA L. , CHACALTANA JESÚS , YAGUI ELENA , GILMAN ROBERT H. , GUILLEN ALFREDO , BLAZES DAVID L. , ESPINOSA BENJAMIN , HALL ERIC , ABDOEL THERESIA H. , SMITS HENK L. , _ _
Published: September 2018

Polymerase chain reaction (PCR) was applied to confirm the diagnosis of brucellosis and to study its clearance in response to the standard treatment regimen with doxycycline and rifampin at hospitals in Callao and Lima, Peru. The PCR confirmed the diagnosis in 23 (91.7%) patients with brucellosis including 12 culture-confirmed cases. For patients treated at the hospital in Callao, PCR was positive for all samples collected during and at the conclusion of treatment and for 76.9% of follow-up samples collected on average 15.9 weeks after completion of treatment. For patients treated at the hospital in Lima, PCR tests were positive for 81.8% of samples collected during treatment, for 33.3% of samples collected at the conclusion of treatment, and for ≥ 50% of samples collected at first, second, and third post-treatment follow-up. Thus, Brucella DNA may persist in the serum weeks to months after completion of the standard treatment regimen.
HIGH PREVALENCE OF HIV AND SYPHILIS IN A REMOTE NATIVE COMMUNITY OF THE PERUVIAN AMAZON
Authors: ZAVALETA CAROL , FERNÁNDEZ CONNIE , KONDA KELIKA , VALDERRAMA YADIRA , VERMUND STEN H. , GOTUZZO EDUARDO
Published: September 2018

Little data are available on how HIV and other sexually transmitted infections (STIs) affect indigenous people in Latin America, including Peru. We conducted a sero-epidemiologic survey of HIV infection and syphilis in a native community, the Chayahuita, an indigenous population in the Amazon region of Peru. The seroprevalences of HIV and syphilis in adults were 7.5% (6 of 80) and 6.3% (5 of 80), respectively. None of the participants had ever used a condom. Male to male sexual behavior was common. At the current levels of HIV prevalence, there is the risk of a negative impact on the survival of the Chayahuita ethnic group as a whole. The outcomes of this study highlight the need for urgent medical and anthropologic approaches to stop HIV transmission in indigenous Amazonian communities.
MULTIPLEX REAL-TIME PCR ASSAY FOR DETECTION OF ENTAMOEBA HISTOLYTICA, GIARDIA INTESTINALIS, AND CRYPTOSPORIDIUM SPP.
Authors: HAQUE RASHIDUL , ROY SHANTANU , SIDDIQUE ABDULLAH , MONDAL UTPAL , RAHMAN S. M. MAZIDUR , MONDAL DINESH , HOUPT ERIC , PETRI WILLIAM A.
Published: September 2018

Entamoeba histolytica, Giardia intestinalis, and Cryptosporidium spp. are not only three of the most important and common diarrhea-causing parasitic protozoa, but they often have similar clinical presentations. Microscopic diagnosis of these parasites is neither sensitive nor specific. Recently, more specific and sensitive alternative molecular methods (polymerase chain reaction [PCR] and antigen detection tests) have been introduced for all three of these parasitic infections. The use of these molecular diagnostic tests in routine diagnostic laboratories is still limited. In this study, we developed a multiplex real-time PCR assay for the simultaneous detection of E. histolytica, G. intestinalis, and Cryptosporidium spp. in one reaction using species-specific probes. This assay was evaluated using clinical specimens and was found to be quite sensitive and specific. The reagents used in this multiplex PCR assay can also be used for detection of these parasites individually. The use of this real-time PCR multiplex assay in developing countries at present will have limited scope for routine diagnosis because the cost will be high for a single test, although in the developed world, the test could see immediate application.
DIARRHEAL DISEASE AMONG HIV-INFECTED ADULTS IN KARNATAKA, INDIA: EVALUATION OF RISK FACTORS AND ETIOLOGY
Authors: BECKER MARISSA L. , COHEN CRAIG R. , CHEANG MARY , WASHINGTON REYNOLD G. , BLANCHARD JAMES F. , MOSES STEPHEN
Published: September 2018

The objectives of this study were to evaluate characteristics associated with diarrhea, the effect of trimethoprim-sulfamethoxazole (TMP/SMX) prophylaxis on diarrhea, the response to treatment with ciprofloxacin and tinidazole (Cipro-TZ™), and presence of enteric pathogens. Adults infected with human immunodeficiency virus with and without diarrhea served as cases and controls, respectively. Participants provided a medical history and underwent a physical examination. Blood was collected for CD4 cell counts and stool for culture. Cases were treated with Cipro-TZ™. Factors associated with a risk of diarrhea included crowded living and no toilet (all P < 0.05). Protective variables (P < 0.05) included a CD4 count greater than 200 cells/mm3 and TMP/SMX prophylaxis. Cases were more likely to have a pathogen identified (P = 0.05). Eighty-six percent of the cases responded to treatment. Important risk factors for diarrhea were identified. Protection by TMP/SMX reinforces the importance of prophylaxis. These data suggest that treatment with an antibiotic and anti-parasitic medication may be effective.
ENVIRONMENTAL ABUNDANCE OF ANOPHELES (DIPTERA: CULICIDAE) LARVAL HABITATS ON LAND COVER CHANGE SITES IN KARIMA VILLAGE, MWEA RICE SCHEME, KENYA
Authors: JACOB BENJAMIN G. , MUTURI EPHANTUS , HALBIG PATRICK , MWANGANGI JOSEPH , WANJOGU R. K. , MPANGA ENOCK , FUNES JOSE , SHILILU JOSEPHAT , GITHURE JOHN , REGENS JAMES L. , NOVAK ROBERT J.
Published: September 2018

A study was carried out at Karima Village in the Mwea Rice Irrigation Scheme in Kenya to assess the impact of rice husbandry and associated land cover change for mosquito larval abundance. A multi-temporal, land use land cover (LULC) classification dataset incorporating distributions of Anopheles arabiensis aquatic larval habitats was produced in ERDAS Imagine version 8.7 using combined images from IKONOS at 4m spatial resolution from 2005 and Landsat Thematic Mapper (TM)™ classification data at 30-meters spatial resolution from 1988 for Karima. Of 207 larval habitats sampled, most were either canals (53.4%) or paddies (45.9%), and only one habitat was classified as a seep (0.5%). The proportion of habitats that were poorly drained was 55.1% compared with 44.9% for the habitats that were well drained. An LULC base map was generated. A grid incorporating each rice paddy was overlaid over the LULC maps stratifying each cell based on levels of irrigation. Paddies/grid cells were classified as 1) well irrigated and 2) poorly irrigated. Early stages of rice growth showed peak larval production during the early part of the cropping cycle (rainy season). Total LULC change for Karima over 16 years was 59.8%. Of those areas in which change was detected, the LULC change for Karima was 4.30% for rice field to built environment, 8.74% for fallow to built environment, 7.19% for rice field to fallow, 19.03% built to fallow, 5.52% for fallow to rice field, and 8.35% for built environment to rice field. Of 207 aquatic habitats in Karima, 54.1 (n = 112) were located in LULC change sites and 45.9 (n = 95) were located in LULC non-change sites. Rice crop LULC maps derived from IKONOS and TM data in geographic information systems can be used to investigate the relationship between rice cultivation practices and higher anopheline larval habitat distribution.
MONKEYPOX ZOONOTIC ASSOCIATIONS: INSIGHTS FROM LABORATORY EVALUATION OF ANIMALS ASSOCIATED WITH THE MULTI-STATE US OUTBREAK
Authors: HUTSON CHRISTINA L. , LEE KEMBA N. , ABEL JASON , CARROLL DARIN S. , MONTGOMERY JOEL M. , OLSON VICTORIA A. , LI YU , DAVIDSON WHITNI , HUGHES CHRISTINE , DILLON MICHAEL , SPURLOCK PAUL , KAZMIERCZAK JAMES J. , AUSTIN CONNIE , MISER LORI , SORHAGE FAYE E. , HOWELL JAMES , DAVIS JEFFREY P. , REYNOLDS MARY G. , BRADEN ZACHARY , KAREM KEVIN L. , DAMON INGER K. , REGNERY RUSSELL L.
Published: September 2018

At the onset of the 2003 US monkeypox outbreak, virologic data were unavailable regarding which animal species were involved with virus importation and/or subsequent transmission to humans and whether there was a risk for establishment of zoonotic monkeypox in North America. Similarly, it was unclear which specimens would be best for virus testing. Monkeypox DNA was detected in at least 33 animals, and virus was cultured from 22. Virus-positive animals included three African species associated with the importation event (giant pouched rats, Cricetomys spp.; rope squirrels, Funisciuris sp.; and dormice, Graphiuris sp.). Virologic evidence from North American prairie dogs (Cynomys sp.) was concordant with their suspected roles as vectors for human monkeypox. Multiple tissues were found suitable for DNA detection and/or virus isolation. These data extend the potential host range for monkeypox virus infection and supports concern regarding the potential for establishment in novel reservoir species and ecosystems.
FOX SQUIRREL (SCIURUS NIGER) ASSOCIATIONS WITH WEST NILE VIRUS
Authors: ROOT J. JEFFREY , OESTERLE PAUL T. , SULLIVAN HEATHER J. , HALL JEFFREY S. , MARLENEE NICOLE L. , MCLEAN ROBERT G. , MONTENIERI JOHN A. , CLARK LARRY
Published: September 2018

Tree squirrels (Sciurus spp.) have been recently shown to be commonly exposed to West Nile virus (WNV). Many characteristics of WNV infections in tree squirrels are unknown. To better understand WNV associations in fox squirrels (S. niger), we conducted mark-recapture sampling (N = 72) and radio telemetry to study the longitudinal seroprevalence, seroconversions, and ectoparasites of these animals during 2005–2006 in northern Colorado. Five seroconversions were documented during this study. The majority of seroconversions occurred during the late summer/fall months. However, one seroconversion was documented over the time period of February to late March 2005. Fleas (Orchopeas howardi) were tested for WNV RNA using real-time PCR techniques. No WNV RNA positive fleas (N = 33) were detected. In addition, urine samples (N = 17) opportunistically collected from fox squirrels were negative for WNV RNA. Results indicate that seroconversions can be observed in fox squirrels during low WNV transmission years.
LONGITUDINAL SURVEY OF KNOCKDOWN RESISTANCE TO PYRETHROID (KDR) IN MALI, WEST AFRICA, AND EVIDENCE OF ITS EMERGENCE IN THE BAMAKO FORM OF ANOPHELES GAMBIAE S.S.
Authors: TRIPET FREDERIC , WRIGHT JENNIFER , CORNEL ANTHON , FOFANA ABDRAHAMANE , MCABEE RORY , MENESES CLAUDIO , REIMER LISA , SLOTMAN MICHEL , THIEMANN TARA , DOLO GUIMOGO , TRAORÉ SEKOU , LANZARO GREGORY
Published: September 2018

Studies aimed at monitoring the spread of knockdown resistance to pyrethroids (kdr) in time and space are particularly useful for detecting barriers to gene flow among the chromosomal and molecular forms of Anopheles gambiae. We used a recently developed polymerase chain reaction assay to estimate changes in kdr frequency that occurred in several mixed-form populations from Mali, West Africa, in the past decade. We found that the kdr allele significantly increased in frequency in most populations but was still absent from the M molecular form. Importantly, within the S molecular form, kdr was detected for the first time in the Bamako chromosomal form. These results provide important insights on the patterns of spread and emergence of pyrethroid knockdown resistance in West Africa.
THE IMPORTANCE OF THE PERIOD OF MALARIAL INFECTION DURING PREGNANCY ON BIRTH WEIGHT IN TROPICAL AFRICA
Authors: COTTRELL GILLES , MARY JEAN-YVES , BARRO DRISSA , COT MICHEL
Published: September 2018

Malaria in pregnant women is related to low birth weight (LBW), a factor contributing to infant mortality. Which period of infection during pregnancy leads to the most harmful consequences is unclear. We analyzed data collected in Burkina Faso for 1190 pregnant women. Birth weight was analyzed through multivariate linear and logistic regressions. Infection after 6 months of pregnancy was related to a decrease in mean birth weight (−105 g, P = 0.02) and a higher risk of low birth weight (AOR = 1.8, P = 0.02). A trend was found between infection before 4 months of pregnancy and a decrease in birth weight (−68 g, P = 0.08). This suggests that the end of pregnancy is the most important period in terms of public health, but infection at the beginning of pregnancy may also have consequences. Malaria prevention policies should be started early in pregnancy, especially by implementing the systematic use of insecticide-treated nets.
EFFECT OF RICE CULTIVATION PATTERNS ON MALARIA VECTOR ABUNDANCE IN RICE-GROWING VILLAGES IN MALI
Authors: DIUK-WASSER MARIA A. , TOURÉ MAHAMOUDOU B. , DOLO GUIMOGO , BAGAYOKO MAGARAN , SOGOBA NAFOMAN , SISSOKO IBRAHIM , TRAORÉ SÉKOU F. , TAYLOR CHARLES E.
Published: September 2018

Irrigation for rice cultivation increases the production of Anopheles gambiae, the main vector of malaria in Mali. Mosquito abundance is highly variable across villages and seasons. We examined whether rice cultivation patterns mapped using remotely sensed imagery can account for some of this variance. We collected entomologic data and mapped land use around 18 villages in the two cropping seasons during two years. Land use classification accuracy ranged between 70% and 86%. The area of young rice explained 86% of the inter-village variability in An. gambiae abundance in August before the peak in malaria transmission. Estimating rice in a 900-meter buffer area around the villages resulted in the best correlation with mosquito abundance, larger buffer areas were optimum in the October and dry season models. The quantification of the relationship between An. gambiae abundance and rice cultivation could have management applications that merit further study.
EFFECT OF LUTZOMYIA LONGIPALPIS SALIVARY GLAND EXTRACTS ON LEUKOCYTE MIGRATION INDUCED BY LEISHMANIA MAJOR
Authors: MONTEIRO MARTA CHAGAS , LIMA HERMÊNIO C. , SOUZA ADELSON A. ALMEIDA , TITUS RICHARD G. , ROMÃO PEDRO ROOSEVELT TORRES , DE QUEIROZ CUNHA FERNANDO
Published: September 2018

The mechanism by which the salivary gland lysate (SGL) of Lutzomyia longipalpis enables Leishmania infection remains under investigation. One possibility is that saliva promotes cellular recruitment leading to development of skin lesions. In this study, we investigated leukocyte recruitment induced by L. major, L. major + SGL, or SGL alone into the peritoneal cavity of BALB/c mice. The administration of L. major with or without SGL induced neutrophil migration six hours after infection. Interestingly, after seven days, the BALB/c mice still had eosinophils and mononuclear cells in their peritoneal cavities. Flow cytometric analysis showed an increase in the CD4+ CD45RBlow T cell subset (effector or memory cells) compared with the CD4+ CD45RBhigh subset (naive cells). Moreover, the co-injection of L. major with SGL enhanced production of interleukin-10. These results suggest that SGL can facilitate Leishmania infection by modulating leukocyte recruitment and Th2 cytokine production at the inflammatory focus.
APPLICATION OF MICROSATELLITE GENOTYPING TO THE STUDY OF A RESTRICTED LEISHMANIA INFANTUM FOCUS: DIFFERENT GENOTYPE COMPOSITIONS IN ISOLATES FROM DOGS AND SAND FLIES
Authors: MONTOYA LILIANA , GÁLLEGO MONTSERRAT , GAVIGNET BÉATRICE , PIARROUX RENAUD , RIOUX JEAN-ANTOINE , PORTÚS MONTSERRAT , FISA ROSER
Published: September 2018

Leishmania infantum polymorphism was studied by DNA microsatellite analysis of 110 L. infantum stocks (94 from dogs, 15 from sand flies, and 1 from a human visceral case) from a rural leishmaniasis-endemic area (Priorat) in northeastern Spain. Three microsatellites of the eight present in three fragments (internal transcribed spacer, Lm4, and Lm2) of L. infantum nuclear DNA are polymorphic inside the focus, resulting in 17 genotypes. Isolates from dogs and sand flies had different allelic compositions and shared only four genotypes. Microsatellite analysis is useful for L. infantum genotyping and epidemiologic tracking. Its application with strains from dogs and vectors in an area endemic for leishmaniasis shows the heterogeneous distribution of L. infantum in hosts living in sympatric conditions.
THE EPIDEMIOLOGY OF VISCERAL LEISHMANIASIS AND ASYMPTOMATIC LEISHMANIAL INFECTION IN A HIGHLY ENDEMIC BANGLADESHI VILLAGE
Authors: BERN CARYN , HAQUE RASHIDUL , CHOWDHURY RAJIB , ALI MUSTAKIM , KURKJIAN KATIE M. , VAZ LOUISE , AMANN JOSEF , WAHED M. A. , WAGATSUMA YUKIKO , BREIMAN ROBERT F. , WILLIAMSON JOHN , SECOR W. EVAN , MAGUIRE JAMES H.
Published: September 2018

We examined the epidemiology of kala-azar and asymptomatic leishmanial infection measured by serologic and leishmanin skin test results in a Bangladeshi community. In a subset, we measured serum retinol, zinc and C-reactive protein (CRP). Kala-azar and seroconversion incidence were 15.6 and 63.1 per 1,000 person-years, respectively. Proximity to a previous kala-azar case increased the likelihood of both kala-azar and asymptomatic infection. Bed net use protected against kala-azar (rate ratio = 0.35, P < 0.01), but not subclinical infection (rate ratio = 1.1, P = 0.82). Kala-azar patients were younger (P < 0.001) and reported lower red meat consumption (P < 0.01) than asymptomatic seropositive individuals. Retinol and zinc levels were lower in current kala-azar patients and those who later developed kala-azar compared with uninfected and asymptomatically infected subjects. The CRP levels were higher in kala-azar patients compared with the other two groups. Low red meat intake and poor zinc and retinol status may characterize a group at higher risk of symptomatic disease.
LARVAL HABITAT DYNAMICS AND DIVERSITY OF CULEX MOSQUITOES IN RICE AGRO-ECOSYSTEM IN MWEA, KENYA
Authors: MUTURI EPHANTUS J. , SHILILU JOSEPHAT I. , GU WEIDONG , JACOB BENJAMIN G. , GITHURE JOHN I. , NOVAK ROBERT J.
Published: September 2018

Introduction of irrigation projects in developing nations has often been blamed for aggravating the problem of mosquito-borne diseases by creating ideal larval habitats for vector mosquitoes. However, whereas several studies have demonstrated the relationship between malaria vectors and irrigation, little work has been done on culicine mosquitoes despite their potential in transmission of filariasis and arboviruses and their significant biting nuisance in these areas. This study examined the diversity of Culex mosquito fauna and their larval habitats at two sites (Murinduko and Kiamachiri) in Mwea, Kenya over a 12-month period. The habitat types present at each site within a 200-meter radius around the study village, including randomly selected paddies and canals, were sampled every two weeks to examine the relationship between vegetation cover, water depth, turbidity, and Culex larval counts. Ten culicine species belonging to four genera were identified, with 73.1% of the total collection comprising of Culex duttoni and Cx. quinquefasciatus. Other species collected included Cx. annulioris, Cx. poicilipes, Cx. cinereus, Cx. tigripes, Cx. trifilatus, Aedes spp., Coquilettidia fuscopennata, and Ficalbia splendens. Murinduko was more diverse than Kiamachiri in terms of species richness (10 versus 7 species) and larval habitat diversity (11 versus 8 habitat types). Paddies, canals, and rain pools were the most diverse habitats in terms of species richness, and ditches, rock pools, and tree holes were the least diverse. Principal component and correlation analyses showed a strong association between three Culex species and the measured habitat characteristics. Culex poicilipes was strongly associated with floating vegetation, Cx. annulioris with clean water containing emergent vegetation, and Cx. quinquefasciatus was associated with turbid water. Seasonal changes in larval counts in water reservoirs and pool and ditch habitats were closely associated with rainfall. These findings provide important information on larval habitat preference for different Culex species, which will be useful in designing and implementation of larval control operations.
BAYESIAN SPATIAL RISK PREDICTION OF SCHISTOSOMA MANSONI INFECTION IN WESTERN CÔTE D’IVOIRE USING A REMOTELY-SENSED DIGITAL ELEVATION MODEL
Authors: BECK-WÖRNER CHRISTIAN , RASO GIOVANNA , VOUNATSOU PENELOPE , N’GORAN ELIÉZER K. , RIGO GERGELY , PARLOW EBERHARD , UTZINGER JÜRG
Published: September 2018

An important epidemiologic feature of schistosomiasis is the focal distribution of the disease. Thus, the identification of high-risk communities is an essential first step for targeting interventions in an efficient and cost-effective manner. We used a remotely-sensed digital elevation model (DEM), derived hydrologic features (i.e., stream order, and catchment area), and fitted Bayesian geostatistical models to assess associations between environmental factors and infection with Schistosoma mansoni among more than 4,000 school children from the region of Man in western Côte d’Ivoire. At the unit of the school, we found significant correlations between the infection prevalence of S. mansoni and stream order of the nearest river, water catchment area, and altitude. In conclusion, the use of a freely available 90 m high-resolution DEM, geographic information system applications, and Bayesian spatial modeling facilitates risk prediction for S. mansoni, and is a powerful approach for risk profiling of other neglected tropical diseases that are pervasive in the developing world.
RESISTANCE TO DEHYDRATION BETWEEN BOUTS OF BLOOD FEEDING IN THE BED BUG, CIMEX LECTULARIUS, IS ENHANCED BY WATER CONSERVATION, AGGREGATION, AND QUIESCENCE
Authors: BENOIT JOSHUA B. , DEL GROSSO NICHOLAS A. , YODER JAY A. , DENLINGER DAVID L.
Published: September 2018

To determine how the bed bug, Cimex lectularius, survives in a dry environment for many months without feeding, water-balance characteristics were compared for all stages from first-instar nymphs to adults. This species is characterized by a low net transpiration rate averaging < 0.2%/h, high tolerance for dehydration (30–40% loss in body water), and an impermeable cuticle as indicated by a high critical transition temperature (CTT) in the 35–40°C range, implying that this insect is adapted for desiccation-hardiness. The capacity of adults to survive for 2 weeks at 0.00av (av = % RH/100) with no access to food or water exemplifies this trait. In contrast to more mature stages, first-instar nymphs contain more water, lose water at a faster rate, experience abrupt water loss at a lower temperature, and survive less time in dry air, suggesting that this stage is the most sensitive to water stress. This insect relies on blood to replenish water stores; none of the stages examined have the capacity to absorb water vapor (critical equilibrium activity, CEA ≥ 0.99av), and they drank only sparingly when offered free water. As the bed bugs progress through their development, they gradually reduce their water requirements while increasing their desiccation resistance. Surviving water stress is considerably enhanced behaviorally by quiescence, characterized by prolonged periods of inactivity, and by the formation of clusters that generate a water-conserving group effect.
Comparison of Trypanosoma cruzi Lineages and Levels of Parasitic DNA in Infected Mothers and Their Newborns
Authors: Virreira Myrna , Truyens Carine , Alonso-Vega Cristina , Brutus Laurent , Jijena Juan , Torrico Faustino , Carlier Yves , Svoboda Michal
Published: September 2018

To better understand the factors involved in maternal–fetal transmission of Trypanosoma cruzi, we compared DNA levels—obtained by use of quantitative real-time PCR and parasitic genotypes determined by PCR amplification followed by hybridization—in Bolivian mothers and their congenitally infected newborns. Mothers and their neonates displayed markedly different parasitic DNA levels, as most maternal estimated parasitemias (> 90%) were < 10 parasites/mL, whereas those of 76% of their newborns were > 1,000 parasites/mL. Comparison of T. cruzi TcII sublineages infecting mothers and newborns showed identity, without evidence of mixed infection in mothers or neonates. Analysis of minor variants of TcIId-genotyped parasites using sequence class probes hybridizing with hypervariable domains of kDNA minicircles showed discrepancies in half of mother/newborn pairs.
Plasmodium falciparum Genetic Diversity in Western Kenya Highlands
Authors: Zhong Daibin , Afrane Yaw , Githeko Andrew , Yang Zhaoqing , Cui Liwang , Menge David M. , Temu Emmanuel A. , Yan Guiyun
Published: September 2018

The present study examined the genetic diversity and population structure of Plasmodium falciparum in western Kenya by analyzing the polymorphism of 12 microsatellite loci and two antigen loci. Malaria in highland areas is unstable and epidemic whereas malaria in lowland areas is endemic. Transmission intensity and malaria prevalence are substantially lower in the highlands than in the lowlands. Despite that the highland parasite populations exhibited reduced number of alleles, lower expected heterozygosity, and infection complexity in comparison to the surrounding lowland population, genetic diversity of the highland populations remained high in comparison to parasites from other meso-endemic regions. More than 70% of infections from western Kenya highland study sites were mixed genotype infections. Small but statistically significant genetic differentiation between highland and lowland populations was detected. These findings are discussed in the context of human travel and local transmission in the study area.
Priority Setting on Malaria Interventions in Tanzania: Strategies and Challenges to Mitigate Against the Intolerable Burden
Authors: Makundi Emmanuel A. , Mboera Leonard E. G. , Malebo Hamisi M. , Kitua Andrew Y.
Published: September 2018

In Tanzania, malaria remains one of the major causes of illness and death. The disease causes major obstacles to social and economic development. The extent of the problem is greatest among children less than five years of age and pregnant women. Malaria has been estimated to cost Tanzania more than US$ 240 million every year in lost gross domestic product, although it can be controlled for a fraction of that sum. Tanzania has actively participated in malaria research and in developing most control tools. However, the use of such tools and scaling up of effective interventions has been a major challenge. Major system constraints include inadequate human, financial, material resources, as well as an inefficient health care system. With an increasing burden with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), there has been a shift in the use of resources whereby more prioritization is given to interventions for HIV/AIDS than for malaria. The country is faced with several challenges including diagnosis, treatment, and control measures. Districts are faced with the inability to generate reliable information needed to make decisions to inform policy and lack skills for priority setting and planning. Budget allocation is not done according to evidence-based priorities, thus leading to stagnation over time. In this report, we present some success stories and discuss the challenges facing scaling up of interventions and propose priority areas to solving the problems.
Reversal of Renal Tubule Transporter Downregulation during Severe Leptospirosis with Antimicrobial Therapy
Authors: Spichler Anne , Ko Albert I. , Silva Everton Fagonde , De Brito Thales , Silva Ana Maria , Athanazio Daniel , Silva Cleiton , Seguro Antonio
Published: September 2018

Tubular dysfunction is a hallmark of severe leptospirosis. Antimicrobial therapy is thought to interfere on renal involvement. We evaluated the expression of a proximal tubule type-3 Na+/H+ exchanger (NHE3) and a thick ascending limb Na+-K+-2Cl− cotransporter (NKCC2) in controls and treated hamsters. Animals infected by a serovar Copenhageni isolate, were treated or not with ampicillin (AMP) and/or N-acetylcysteine (NAC). Leptospiral antigen(s) and expression of renal transporters were evaluated by immunohistochemistry, and serum thiobarbituric acid (TBARS) was quantified. Infected hamsters had high amounts of detectable leptospiral antigen(s) in target tissues while renal expression of NHE3 and NKCC2 decreased. Ampicillin treatment was associated with minimal or no detection of leptospiral antigens, normal expression of NHE3 and NKCC2 transporters, and reduced levels of TBARS. NAC effect was restricted to lowering TBARS. Early and late AMP treatment rescued tubular defects in severe leptospirosis disease, and there was no evidence of benefit from antioxidant therapy.
Uncertainty in Malaria Control in Tanzania: Crossroads and Challenges for Future Interventions
Authors: Mboera Leonard E. G. , Makundi Emmanuel A. , Kitua Andrew Y.
Published: September 2018

In Tanzania malaria is the leading cause of morbidity and mortality, especially in children under 5 years. The disease ranks number one in both outpatient and inpatient statistics. The socio-economic impact of malaria is so high that it contributes highly to poverty and underdevelopment. Efforts made during the past century to combat and control malaria have not been successful. The prospects of achieving the Abuja declaration targets are uncertain within the remaining period of time. Currently, the Ministry of Health through a 5-year strategic plan advocates four main approaches in the fight against the disease. These include improved case management, vector control using insecticide treated mosquito nets, prevention and control of malaria in pregnancy and epidemic preparedness, prevention and control. However, these strategies face various challenges including inadequate human, financial, and material resources; inefficiency in the healthcare system that is incapable of providing quality health services and access to prompt diagnosis and treatment; lack of an effective disease surveillance system; and an inefficient health education communication mechanism. Tanzania is at the crossroads and is challenged with the need to introduce a new antimalarial treatment regimen and the reintroduction of DDT for indoor residual spray. Unless malaria control strategy adopts an integrated approach its success is far from being realized. This article reviews the current malaria control strategies and its challenges in Tanzania and proposes new strategies.
Geographic Distribution of Human Immunodeficiency Virus in South Africa
Authors: Kleinschmidt Immo , Pettifor Audrey , Morris Natashia , MacPhail Catherine , Rees Helen
Published: September 2018

In common with most countries, little is know about the geographic distribution of human immunodeficiency virus (HIV) in South Africa. Variations in HIV infection of persons 15–24 years of age were modeled and mapped using generalized linear spatial models and Bayesian prediction based on data from a national HIV household survey conducted in 2003 and comprising 11,904 youth from approximately 700 enumeration areas that were randomly selected from the national census. The maps show considerable variation in HIV prevalence within provinces. The lowest levels were found in inland rural areas of the Western Cape, and the highest in northwestern parts of KwaZulu Natal, southern Mpumalanga, and eastern Free State. Prevalence of HIV was associated with ethnicity, urban status, and unemployment. Detailed maps of HIV prevalence can be effectively used in guiding and focusing intervention programs to areas of particular need.
Neurologic Signs of Ciguatera Disease: Evidence of their Persistence
Authors: Chateau-Degat M.-L. , Beuter A. , Vauterin G. , Nguyen N. L. , Chinain M. , Darius T. , Legrand A.-M. , Chansin R. , Dewailly E.
Published: September 2018

Ciguatoxins exert their effect on the voltage-sensitive sodium channels of the cellular membranes of all excitable tissues. This effect confers to ciguatera disease (CD) its neurologic hallmarks. A prospective study among French Polynesian adults over a two-month period was conducted to characterize and determine the persistence of neurologic symptoms of CD. We compared 47 patients with CD with 125 controls. In the acute phase of the disease, patients had mainly sensory disturbances as detected by an hypoesthesia on the palm of the hand and poorer sway performance compared with controls. Follow-up two months showed improvement of sway performance that eventually reaching control levels. However, for light-touch threshold, even if we observed a decrease threshold towards normal values, more than 50% of patients did not reach normal values 60 days after disease onset. Our results support the existence of neurologic impairments of CD and suggest their persistence for at least two months after onset.
The Cost-Effectiveness of Parasitologic Diagnosis for Malaria-Suspected Patients in an Era of Combination Therapy
Authors: Lubell Yoel , Reyburn Hugh , Mbakilwa Hilda , Mwangi Rose , Chonya Kini , Whitty Christopher J. M. , Mills Anne
Published: September 2018

The introduction of artemisinin-based combination therapy in sub-Saharan Africa has prompted calls for increased use of parasitologic diagnosis for malaria. We evaluated the cost-effectiveness of rapid diagnostic tests (RDTs) in comparison to microscopy in guiding treatment of non-severe febrile illness at varying levels of malaria endemicity using data on test accuracy and costs collected as part of a Tanzanian trial. If prescribers complied with current guidelines, microscopy would give rise to lower average costs per patient correctly treated than RDTs in areas of both high and low transmission. RDT introduction would result in an additional 2.3% and 9.4% of patients correctly treated, at an incremental cost of $25 and $7 in the low and high transmission settings, respectively. Cost-effectiveness would be worse if prescribers do not comply with test results. The cost of this additional benefit may be higher than many countries can afford without external assistance or lower RDT prices.
Enteroaggregative Escherichia coli in Venda, South Africa: Distribution of Virulence-Related Genes by Multiplex Polymerase Chain Reaction in Stool Samples of Human Immunodeficiency Virus (HIV)–Positive and HIV-Negative Individuals and Primary School Children
Authors: Samie Amidou , Obi Chikwelu Larry , Dillingham Rebecca , Pinkerton Relana C. , Guerrant Richard L.
Published: September 2018

We used a multiplex polymerase chain reaction (PCR) and a quantitative real-time PCR to determine the distribution of three enteroaggregative Escherichia coli (EAEC) virulence-related genes in stool samples from hospital patients and school children in the Venda region of South Africa. At least one gene was found in 52 (16.5%) samples, 50 (19.6%) from hospitals and 2 (3%) from schools. The AA probe was found in 36 (69%), the aggR gene was found in 41 (79%), and the aap gene was found in 49 (94%) of all positive samples. EAEC was significantly associated with diarrhea and intestinal inflammation and was significantly higher (χ2 = 5.360, P = 0.021) in human immunodeficiency virus (HIV)–positive persons (29.5%) than in HIV-negative persons (13.7%). The presence of EAEC genes was significantly associated with occult blood (χ2 = 30.543, P < 0.0001) in the stool samples. This study suggests that the clinical presentation of EAEC infection may be directly related to the bacterial load as well as to the genetic characteristics of the strains involved.
Acute Respiratory Failure in Adult Patients with Dengue Virus Infection
Authors: Wang Chin-Chou , Liu Shih-Feng , Liao Shang-Chih , Lee Ing-Kit , Liu Jien-Wei , Lin An-Shen , Wu Chao-Chien , Chung Yu-Hsiu , Lin Meng-Chih
Published: September 2018

To investigate clinical course and outcome of dengue with acute respiratory failure (ARF), and to identify related risk factors for acquiring ARF in dengue, we retrospectively studied 11 dengue patients with ARF. From June to December 2002, a total of 606 adult patients were diagnosed as having dengue. Eleven (1.8%) of 606 dengue patients had complications of ARF. The main causes of ARF were sepsis (n = 6, 54.5%) and upper gastrointestinal (UGI) bleeding (n = 3, 27.3%). The mortality rate was 72.7% (n = 8). Additionally, univariate analysis showed that age, dyspnea, cough, prothrombin time, activated partial thromboplastin time, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, creatinine, albumin, renal insufficiency, acute renal failure, acute hepatic failure, UGI bleeding, and combination bacterial infection were significantly predictive variables associated with dengue patients with ARF.
Monitoring and Deterring Drug-Resistant Malaria in the Era of Combination Therapy
Authors: Laufer Miriam K. , Djimdé Abdoulaye A. , Plowe Christopher V.
Published: September 2018

As chloroquine and sulfadoxine-pyrimethamine (SP) are replaced by more effective artemisinin-based combination therapies (ACTs), strategies for monitoring (and, if possible, deterring) drug-resistant malaria must be updated and optimized. In vitro methods for measuring resistance will be critical for confirming and characterizing resistance to ACTs. Molecular markers are useful for tracking the emergence and dissemination of resistance and guiding treatment policy where resistance is low or moderate. Genomic approaches may help identify molecular markers for resistance to artemisinins and their partner drugs. Studies of reported ACT treatment failure should include assessing factors other than resistance that affect efficacy, including pharmacokinetics. Longitudinal clinical trials are particularly useful for comparing the benefits and risks of repeated treatment in high transmission settings. The malaria research and control community should not fail to exploit this opportunity to apply the lessons of the last 50 years to extend the useful therapeutic lives of ACTs.
Artemisinin-Based Combination Treatment of Falciparum Malaria
Authors: Nosten François , White Nicholas J.
Published: September 2018

Artemisinin-based combination treatments (ACTs) are now generally accepted as the best treatments for uncomplicated falciparum malaria. They are rapidly and reliably effective. Efficacy is determined by the drug partnering the artemisinin derivative and, for artesunate–mefloquine, artemether–lumefantrine, and dihydroartemisinin–piperaquine, this usually exceeds 95%. Artesunate–sulfadoxine–pyrimethamine and artesunate–amodiaquine are effective in some areas, but in other areas resistance to the partner precludes their use. There is still uncertainty over the safety of artemisinin derivatives in the first trimester of pregnancy, when they should not be used unless there are no effective alternatives. Otherwise, except for occasional hypersensitivity reactions, the artemisinin derivatives are safe and remarkably well tolerated. The adverse effect profiles of the artemisinin-based combination treatments are determined by the partner drug. Most malaria endemic countries have now adopted artemisinin-based combination treatments as first-line treatment of falciparum malaria, but in most of these only a minority of the patients that need artemisinin-based combination treatments actually receive them.
An Eight-Year Study of Epidemiologic Features of Enterovirus 71 Infection In Taiwan
Authors: Chen Shou-Chien , Chang Hsiao-Ling , Yan Tsong-Rong , Cheng Yan-Tzong , Chen Kow-Tong
Published: September 2018

In 1998, an epidemic of enterovirus 71 (EV 71) infection occurred in Taiwan. The purpose of this study was to assess the epidemiology of EV 71 infection in Taiwan. Between March 1998 and December 2005, a total of 1,548 severe cases of hand-foot-mouth disease and herpangina (HFMD/HA) was reported to the Center for Disease Control in Taiwan. A seasonal variation in number of severe cases was observed, with the annual peak in second quarter. Deaths from severe HFMD/HA varied from year to year (χ2 for trend = 6.781, P = 0.009). Most (92%) cases occurred in children ≤ 4 years of age. Children infected with EV 71 had higher risk of pulmonary edema/hemorrhage and encephalitis than those not infected. Infection with EV 71 has emerged as an important infectious disease causing serious clinical illness and deaths of young children. Vaccine development is recommended to prevent future EV 71 infections.
Medicine Sellers and Malaria Treatment in Sub-Saharan Africa: What Do They Do and How Can Their Practice Be Improved?
Authors: Goodman Catherine , Brieger William , Unwin Alasdair , Mills Anne , Meek Sylvia , Greer George
Published: September 2018

Medicine sellers are widely used for fever and malaria treatment in sub-Saharan Africa, but concerns surround the appropriateness of drugs and information provided. Because there is increasing interest in improving their services, we reviewed the literature on their characteristics and interventions to improve their malaria-related practices. Sixteen interventions were identified, involving a mixture of training/capacity building, demand generation, quality assurance, and creating an enabling environment. Although evidence is insufficient to prove which approaches are superior, tentative conclusions were possible. Interventions increased rates of appropriate treatment, and medicine sellers were willing to participate. Features of successful interventions included a comprehensive situation analysis of the legal and market environment; buy-in from medicine sellers, community members and government; use of a combination of approaches; and maintenance of training and supervision. Interventions must be adapted to include artemisinin-based combination therapies, and their sustainability and potential to operate at a national level should be further explored.
Associations Between Placental and Cord Blood Malaria Infection and Fetal Malnutrition in an Area of Malaria Holoendemicity
Authors: Adebami O. Joseph , Owa J. Aderinsola , Oyedeji G. Ademola , Oyelami O. Akibu , Omoniyi-Esan G. Olutoyin
Published: September 2018

The objective of this study was to determine the role of malaria in the etiology of fetal malnutrition in Nigeria. This study took place at the Neonatal and Maternity Units of the Wesley Guild Hospital, Ilesa, Nigeria. This is a prospective study of 304 consecutive, singleton, term live births delivered between January and August 2002. Anthropometric and clinical data were recorded. Fetal malnutrition (FM; failure to acquire adequate quantum of fat and muscle mass during intrauterine growth) was diagnosed using clinical assessment of fetal nutritional status (CANS) and the score (CANSCORE) adapted by Metcoff. The placenta tissues were examined for malaria pigments and parasites, and placental and cord blood smears were examined for parasites. Babies were followed up in the neonatal period for clinical malaria. Babies were grouped into those with malaria-infected placental and cord blood specimens and those without. The two groups were compared with regard to the proportions with FM and complications of FM. Three hundred four placental and cord blood specimens were examined for malaria. Of the 304, 101 (33.2%) of the placental and 67 (22.0%) of the cord blood specimens were positive for malaria. Sixty-six (21.7%) of the 304 babies had FM. Forty-four (66.7%) of the 66 placental blood specimens of babies with FM were positive for malaria, whereas 57 (24.0%) of the 238 placentae of babies without FM had placental malaria (χ2 =42.5, P < 0.0001). Similarly, 27 (40.9%) of 66 babies with FM compared with 40 (16.8%) among 238 babies without FM had malaria parasites in the cord blood (χ2 =17.5, P < 0.001). The means of birth weight, ponderal index, and placenta weight were significantly lower among the babies of mothers with malaria-infected placentae than those without (P < 0.05 in all cases). Lack of antenatal care, primiparity, and failure to have chemoprophylaxis against malaria were the maternal factors found to be associated with placental malaria infection. Placental malaria is a major factor in the etiology of FM in Nigeria.
Transgenic Mosquitoes and the Fight Against Malaria: Managing Technology Push in a Turbulent GMO World
Authors: Knols Bart G. J. , Bossin Hervé C. , Mukabana Wolfgang R. , Robinson Alan S.
Published: September 2018

Genetic modification (GM) of mosquitoes (which renders them genetically modified organisms, GMOs) offers opportunities for controlling malaria. Transgenic strains of mosquitoes have been developed and evaluation of these to 1) replace or suppress wild vector populations and 2) reduce transmission and deliver public health gains are an imminent prospect. The transition of this approach from confined laboratory settings to open field trials in disease-endemic countries (DECs) is a staged process that aims to maximize the likelihood of epidemiologic benefits while minimizing potential pitfalls during implementation. Unlike conventional approaches to vector control, application of GM mosquitoes will face contrasting expectations of multiple stakeholders, the management of which will prove critical to safeguard support and avoid antagonism, so that potential public health benefits can be fully evaluated. Inclusion of key stakeholders in decision-making processes, transfer of problem-ownership to DECs, and increased support from the wider malaria research community are important prerequisites for this. It is argued that the many developments in this field require coordination by an international entity to serve as a guiding coalition to stimulate collaborative research and facilitate stakeholder involvement. Contemporary developments in the field of modern biotechnology, and in particular GM, requires competencies beyond the field of biology, and the future of transgenic mosquitoes will hinge on the ability to govern the process of their introduction in societies in which perceived risks may outweigh rational and responsible involvement.