bluuebunny/crossref_metadata_2025 huggingface dataset:
STATUS OF FOREST ONCHOCERCIASIS IN THE LOWER CROSS RIVER BASIN, NIGERIA: ENTOMOLOGIC PROFILE AFTER FIVE YEARS OF IVERMECTIN INTERVENTION
Authors: OPARA KENNETH N. , FAGBEMI OLAKUNLE B. , EKWE ASUQUO , OKENU DANIEL M. N.
Published: September 2018

In the Lower Cross River basin in Nigeria, no pre-control entomologic profile of Onchocerca volvulus infection in the local Simulium damnosum population was available prior to the initiation of an ivermectin control program in 1995. A longitudinal entomologic study was therefore carried out over a 12-month period (January–December 2001) at the Agbokim waterfalls and Afi River, which are breeding sites of S. damnosum in the river basin. A total of 9,287 adult S. damnosum were caught on human bait; 9,048 (97.43%) were dissected, of which 313 (3.46%) were infected. Annual biting rates (ABRs) of 42,419 and 28,346 bites per persons per year were recorded at the Agbokim Waterfalls and Afi River, respectively. The annual transmission potential (ATP) was 419 infective larvae per person per year at the Agbokim Waterfalls and 427 at the Afi River. Monthly biting rate and monthly transmission potential varied significantly (P < 0.05) at the two sites. Transmission was highly seasonal from April to September, corresponding to the peak biting period of the vector. The high ATP and ABR values are a measure of the mesoendemicity of onchocerciasis in the river basin. There was a significant F0.05 (1, 10) (P < 0.05) variation in the relative fly abundance from both sites. It was observed that human activities such as farming, fishing, timber cutting, and hunting are done in the early morning and late afternoon, which corresponds to the peak diurnal biting period of the vector. Changes in these practices and attitudes may markedly affect the disease intensity and transmission.
RISK OF INTESTINAL HELMINTH AND PROTOZOAN INFECTION IN A REFUGEE POPULATION
Authors: GARG PARVEEN K. , PERRY SHARON , DORN MARTHA , HARDCASTLE LAURA , PARSONNET JULIE
Published: September 2018

With continuing emigration from endemic countries, screening for parasitic infections remains a priority in U.S. communities serving refugee and immigrant populations. We report the prevalence of helminths and protozoa as well as demographic risk factors associated with these infections among 533 refugees seen at the Santa Clara County, California, Refugee Clinic between October 2001 and January 2004. Stool parasites were identified from 14% of refugees, including 9% found to have one or more protozoa and 6% found to have at least one helminth. Most common protozoan infections were Giardia lamblia (6%) and Dientamoeba fragilis (3%), and for helminths, hookworm (2%). Protozoa were more frequent in refugees < 18 years of age (OR: 2.2 [1.2–4.2]), whereas helminths were more common in refugees from South Central Asia (OR: 8.0 [2.3–27.7]) and Africa (OR: 5.9 [1.6–21.6]) when compared with refugees from Eastern Europe and the Middle East. Among helminths, Ascaris lumbricoides and hookworm were concentrated among South Central Asians (6 of 7 and 10 of 11 cases, respectively), whereas Strongyloides stercoralis was predominantly found in Africans (5 of 7 cases). Although predeparture empirical treatment programs in Saharan Africa may have helped to reduce prevalence among arriving refugees from this region, parasitic infection is still common among refugees to the United States with helminth infections found in more specific populations. As refugees represent only a fraction of recent immigrants from endemic countries, current studies in nonrefugee groups are also needed.
HEPATITIS A IN LEBANON: A CHANGING EPIDEMIOLOGICAL PATTERN
Authors: SACY ROBERT G. , HADDAD MIRNA , BAASIRI GHASSAN , KHORIATI ADLETTE , GERBAKA BERNARD J. , ABU-ELYAZEED REMON
Published: September 2018

In this multicenter study in Lebanon, hepatitis A virus (HAV) seroprevalence rates were surveyed by age, gender, and socioeconomic factors. Blood samples collected from 606 subjects aged 1 to 30 years were analyzed for anti-HAV IgG. Age was the most important factor influencing HAV seroprevalence. HAV seroprevalence rates in the current study were about 78% in the ≥ 21 years age group, 28% in the 6–10 years age group, and 11% in the 1–5 years age group as compared with 97.7% in adults, 85% in children aged 6–12 years, and 40% in children aged 1 to 5 years in previous studies, demonstrating a shift in HAV seroprevalence from the younger to the higher age groups. In light of the severity of the disease in adults and availability of safe and effective vaccines against HAV infection, introduction of HAV vaccination into the national immunization schedule of Lebanon should be considered.
ASSESSMENT OF A SIMPLIFIED METHOD FOR COUNTING LEUKOCYTIC MALARIA PIGMENT
Authors: LELL BERTRAND , MISSINOU MICHEL A. , ISSIFOU SAADOU , MATSIEGUI PIERRE-BLAISE , OLOLA CHRISTOPHER H. O. , TAYLOR TERRIE E. , KREMSNER PETER G.
Published: September 2018

Severe and fatal malaria is associated with the increased presence of malaria hemozoin in peripheral phagocytes. Large studies of this relationship are hampered by the fact that identifying and counting phagocytes on thick blood smears is time consuming. Distinguishing which mononuclear cells are monocytes and which granulocytes are neutrophils requires time and careful training. In this study, we evaluated a simplified method in which only the proportions of hemozoin-containing mononuclear cells and granulocytes are counted. Thick blood films from 471 Gabonese children with malaria were evaluated. We found a linear relationship and a strong correlation between the proportions of hemozoin-containing monocytes versus mononuclear cells (r = 0.85) and neutrophils versus polymorphonuclear cells (r = 0.93), respectively. The two methods had similar predictive values, as estimated by receiver operating characteristics curves. This simplified method can be used to estimate the amount of extra-erythrocytic pigment in peripheral blood, and we suggest that it may be particularly suitable for very large studies.
THE ROLE AND SIGNIFICANCE OF SPUTUM CULTURES IN THE DIAGNOSIS OF MELIOIDOSIS
Authors: VELD DIANA HUIS IN ’T , WUTHIEKANUN VANAPORN , CHENG ALLEN C. , CHIERAKUL WIRONGRONG , CHAOWAGUL WIPADA , BROUWER ANNEMARIE E. , WHITE NICHOLAS J. , DAY NICHOLAS P. J. , PEACOCK SHARON J.
Published: September 2018

Pneumonia is a common manifestation of melioidosis, the disease caused by Burkholderia pseudomallei. In this study, we defined the prognostic significance of a positive sputum culture. A total of 712 patients presenting to Sappasithiprasong Hospital, Ubon Ratchathani, Thailand, with melioidosis between January 1992 and December 2002 had a sputum culture performed during admission, which was positive for B. pseudomallei in 444 patients (62%). The median duration of sputum positivity was 9 days (range, 1 to 49 days). Sputum cultures were negative in 32% of patients with radiologic changes suggestive of pulmonary involvement. Overall in-hospital mortality was 48%. A positive sputum culture was associated with mortality (adjusted OR 2.8, 95% CI: 1.9, 4.0; P < 0.001). This was independent of renal disease, a prior history of melioidosis, positive blood cultures, and other potential confounders. The presence of B. pseudomallei in the sputum of patients with melioidosis is associated with a poorer prognosis.
TRANSCRIPTION OF THE RICKETTSIA FELIS OMPA GENE IN NATURALLY INFECTED FLEAS
Authors: ZAVALA-CASTRO JORGE E. , SMALL MELISSA , KENG COLETTE , BOUYER DONALD H. , ZAVALA-VELÁZQUEZ JORGE , WALKER DAVID H.
Published: September 2018

Rickettsia felis is maintained transovarially in Ctenocephalides felis fleas in a widespread geographic distribution and is transmitted to humans and animals, including opossums. This rickettsia is phylogenetically a member of the spotted fever group, most closely related to Rickettsia akari and R. australis. An unusual feature of this rickettsia is that the gene for the outer membrane protein A (OmpA) is interrupted by stop codons. To determine if this putatively dying gene is expressed, mRNA was extracted from laboratory-maintained, R. felis–infected cat fleas. Reverse transcriptase–polymerase chain reaction amplification of three segments of the ompA gene indicated that mRNA of ompA is actively transcribed in fleas. The cDNA sequences expressed represented mRNA of the first 1860-basepair segment of ompA, which includes domains I and II, part of domain III, the region from site 1836 to site 2180, despite the presence of several stop codons, and the open reading frame from site 2788 to site 3837. The detected sequences showed several differences in the amino acid composition when compared with the previously reported sequence.
NEW EVIDENCE OF THE EFFECTS OF AGRO-ECOLOGIC CHANGE ON MALARIA TRANSMISSION
Authors: KEBEDE ASNAKEW , McCANN JAMES C. , KISZEWSKI ANTHONY E. , YE-EBIYO YEMANE
Published: September 2018

Although maize pollen is known to provide nutrition for larval anopheline mosquitoes, the epidemiologic relationship between maize agriculture and malaria transmission has never been defined. To determine whether recent changes in malaria transmission in Ethiopia might be linked to the spread of maize as a commercial crop, we compared malaria transmission and maize cultivation intensity in 21 villages in the Bure District of northwestern Ethiopia where maize cultivation has recently expanded. The cumulative incidence in high maize cultivation areas was 9.5 times higher than in areas with less maize. A chi-square goodness-of-fit test results showed that malaria cases were not distributed evenly among categories of maize cultivation intensity, (χ2 = 1,578, P < 0.001). A Poisson regression suggested that the intensity of maize cultivation, controlled for differences in elevation between sites, was positively and significantly correlated with malaria incidence. Thus, the intensity of maize cultivation was associated with exacerbated human risk of malaria in Bure.
THERAPEUTIC EFFICACY OF SULFADOXINE-PYRIMETHAMINE AND AMODIAQUINE AMONG CHILDREN WITH UNCOMPLICATED PLASMODIUM FALCIPARUM MALARIA IN ZANZIBAR, TANZANIA
Authors: LEMNGE MARTHA M. , ALI ABDULLAH S. , MALECELA EZEKIEL K. , SAMBU EDWARD , ABDULLA RAHMA , JUMA MOHAMED S. , FAKIH KHATIBU , ABDULLA KHAFIDH H. , NJAU RITHA J.
Published: September 2018

The efficacy of sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ) was assessed at Kivunge and Micheweni in Zanzibar, Tanzania, in 2001. The main objective was to obtain baseline data after observations of high levels of chloroquine treatment failures. Children (6–59 months) were randomized to receive either drug. At Kivunge, SP and AQ were given to 64 and 63 cases, while for Micheweni, 61 and 70 cases were treated. Main findings were overall high rates (> 90%) of adequate clinical response (ACR) with AQ. A lower ACR was seen in the SP group at Kivunge (87.1%) compared with Micheweni (94.8%). Furthermore, in the ACR group, 16.7% AQ parasitological resistance (RI–RIII) was encountered at Kivunge. Most of the cases of SP parasitological resistance (14.5%; RI/RII) were seen at Micheweni. Notwithstanding this, the overall treatment failure was only 9.2% with SP and 5.5% with AQ. The Zanzibar Ministry of Health has since reviewed its antimalarial drug policy.
PREVALENCE OF PLASMODIUM FALCIPARUM MUTATIONS ASSOCIATED WITH ANTIMALARIAL DRUG RESISTANCE DURING AN EPIDEMIC IN KUNA YALA, PANAMA, CENTRAL AMERICA
Authors: SAMUDIO FRANKLYN , SANTAMARÍA ANA M. , OBALDÍA NICANOR III , PASCALE JUAN M. , BAYARD VICENTE , CALZADA JOSE E.
Published: September 2018

A molecular epidemiology study was conducted to determine the distribution of antimalarial drug resistance alleles among field isolates of Plasmodium falciparum. Samples were obtained during an epidemic affecting Kuna Amerindians in Panama. A high prevalence of mutations associated with chloroquine, pyrimethamine, and sulfadoxine was observed. Genotype analysis of msp2 revealed a low genetic diversity of P. falciparum parasites circulating in the studied area. The public health implications of these findings for the Central American region are discussed.
RANDOMIZED, CONTROLLED, DOUBLE-BLIND TRIAL OF DAILY ORAL AZITHROMYCIN IN ADULTS FOR THE PROPHYLAXIS OF PLASMODIUM VIVAX MALARIA IN WESTERN THAILAND
Authors: HEPPNER D. GRAY , WALSH DOUGLAS S. , UTHAIMONGKOL NICHAPAT , TANG DOUGLAS B. , TULYAYON SOMCHIT , PERMPANICH BARNYEN , WIMONWATTRAWATEE THEERA , CHUANAK NIPHON , LAOBOONCHAI ANINTITA , SOOKTO PRASIT , BREWER THOMAS G. , MCDANIEL PHILIP , EAMSILA CHIRAPA , YONGVANITCHIT KOSOL , UHL KATHLEEN , KYLE DENNIS E. , KEEP LISA W. , MILLER ROBERT E. , WONGSRICHANALAI CHANSUDA
Published: September 2018

We assessed the prophylactic efficacy of azithromycin (250 mg/day) against malaria in 276 adults in western Thailand in a randomized, double-blind, placebo-controlled trial. After antimalarial suppressive treatment, volunteers were randomized in a 2:1 ratio to either the azithromycin or placebo, respectively. Study medication was given for an average of 74 days. The azithromycin group (n = 179) had five endpoint parasitemias (1 Plasmodium vivax and 4 P. falciparum), and the placebo group (n = 97) had 28 endpoint parasitemias (21 P. vivax, 5 P. falciparum, and 2 mixed infections). Adverse events and compliance and withdrawal rates were similar in both groups. The protective efficacy (PE) of azithromycin was 98% for P. vivax (95% confidence interval [CI] = 88–100%). There were too few cases to reliably estimate the efficacy of azithromycin for P. falciparum (PE =71%, 95% C =−14–94%). We conclude that daily azithromycin was safe, well-tolerated, and had a high efficacy for the prevention of P. vivax malaria.
EVALUATION OF A REAL-TIME POLYMERASE CHAIN REACTION ASSAY FOR THE DIAGNOSIS OF MALARIA IN PATIENTS FROM THAILAND
Authors: SWAN HEATHER , SLOAN LYNNE , MUYOMBWE ANTHONY , CHAVALITSHEWINKOON-PETMITR PORNTIP , KRUDSOOD SRIVICHA , LEOWATTANA WATTANA , WILAIRATANA POLRAT , LOOAREESUWAN SORNCHAI , ROSENBLATT JON
Published: September 2018

We compared the diagnosis of malaria in 297 patients from Thailand by a real-time polymerase chain reaction (PCR) assay using the LightCycler with conventional microscopy using Giemsa-stained thick and thin blood films. The PCR assay can be completed in one hour and has the potential to detect and identify four species of Plasmodium in a single reaction by use of melting temperature curve analysis (however, we did not detect Plasmodium ovale in this study). Blood was collected, stored, and transported on IsoCode STIX, which provide a stable matrix for the archiving and rapid simple extraction of DNA. A genus-specific primer set corresponding to the 18S ribosomal RNA was used to amplify the target sequence. Fluorescence resonance energy technology hybridization probes were designed for P. falciparum over a region containing basepair mismatches, which allowed differentiation of the other Plasmodium species. The PCR results correlated with the microscopic results in 282 (95%) of 297 patient specimens. Most of these were single-species infections caused by P. vivax (150) and P. falciparum (120), along with 5 P. malariae, 2 mixed infections (P. falciparum and P. vivax), and 5 negative specimens. No negative microscopy specimens were positive by PCR (100% specificity for detection of any Plasmodium). The 15 discrepant results could not be resolved, but given the subjective nature of microscopy and the analytical objectivity of the PCR, the PCR results may be correct. The ability of the PCR method to detect mixed infections or to detect P. ovale could not be determined in this study. Within the limitations of initial equipment costs, this real-time PCR assay is a rapid, accurate, and efficient method for the specific diagnosis of malaria. It may have application in clinical laboratories, as well as in epidemiologic studies and antimalarial efficacy trials.
PARENTERAL ADMINISTRATION OF IVERMECTIN IN A PATIENT WITH DISSEMINATED STRONGYLOIDIASIS
Authors: TURNER STEPHEN A. , MACLEAN J. DICK , FLECKENSTEIN LAWRENCE , GREENAWAY CHRISTINA
Published: September 2018

We report the case of a 23-year-old Caribbean man with disseminated strongyloidiasis (co-infected with human T cell lymphotropic virus I/II)), severe hypoalbuminemia, and a paralytic ileus. Subcutaneous ivermectin (200 μg/kg) was administered daily for 14 days because of the inability to effectively administer oral albendazole and oral ivermectin. Three hours after the third daily dose of oral ivermectin, the serum ivermectin concentration was only 0.8 ng/mL, but it increased several fold to 5.8 ng/mL 16 hours after the first dose of subcutaneous ivermectin. During the course of subcutaneous treatment, ivermectin clearance was higher than expected (46.0 L/hour, normal = 31.8 L/hour). This is likely the result of severe hypoalbuminemia since ivermectin is highly protein bound. The ability to achieve adequate levels of ivermectin after oral administration in patients with disseminated strongyloidiasis may be impaired, highlighting the need for alternative routes of administration of ivermectin in these patients.
EFFECT OF HOME-BASED WATER CHLORINATION AND SAFE STORAGE ON DIARRHEA AMONG PERSONS WITH HUMAN IMMUNODEFICIENCY VIRUS IN UGANDA
Authors: LULE JOHN R. , MERMIN JONATHAN , EKWARU JOHN PAUL , MALAMBA SAMUEL , DOWNING ROBERT , RANSOM RAYMOND , NAKANJAKO DAMALIE , WAFULA WINNIE , HUGHES PETER , BUNNELL REBECCA , KAHARUZA FRANK , COUTINHO ALEX , KIGOZI AMINAH , QUICK ROBERT
Published: September 2018

Diarrhea is frequent among persons infected with human immunodeficiency virus (HIV) but few interventions are available for people in Africa. We conducted a randomized controlled trial of a home-based, safe water intervention on the incidence and severity of diarrhea among persons with HIV living in rural Uganda. Between April 2001 and November 2002, households of 509 persons with HIV and 1,521 HIV-negative household members received a closed-mouth plastic container, a dilute chlorine solution, and hygiene education (safe water system [SWS]) or simply hygiene education alone. After five months, HIV-positive participants received daily cotrimoxazole prophylaxis (160 mg of trimethoprim and 800 mg of sulfamethoxazole) and were followed for an additional 1.5 years. Persons with HIV using SWS had 25% fewer diarrhea episodes (adjusted incidence rate ratio [IRR] = 0.75, 95% confidence interval [CI] = 0.59–0.94, P = 0.015), 33% fewer days with diarrhea (IRR = 0.67, 95% CI = 0.48–0.94, P = 0.021), and less visible blood or mucus in stools (28% versus 39%; P < 0.0001). The SWS was equally effective with or without cotrimoxazole prophylaxis (P = 0.73 for interaction), and together they reduced diarrhea episodes by 67% (IRR = 0.33, 95% CI = 0.24–0.46, P < 0.0001), days with diarrhea by 54% (IRR = 0.46, 95% CI = 0.32–0.66, P < 0.0001), and days of work or school lost due to diarrhea by 47% (IRR = 0.53, 95% CI = 0.34–0.83, P < 0.0056). A home-based safe water system reduced diarrhea frequency and severity among persons with HIV living in Africa and large scale implementation should be considered.
DIVERSITY OF BAT-ASSOCIATED LEPTOSPIRA IN THE PERUVIAN AMAZON INFERRED BY BAYESIAN PHYLOGENETIC ANALYSIS OF 16S RIBOSOMAL DNA SEQUENCES
Authors: MATTHIAS MICHAEL A. , DÍAZ M. MÓNICA , CAMPOS KALINA J. , CALDERON MARITZA , WILLIG MICHAEL R. , PACHECO VICTOR , GOTUZZO EDUARDO , GILMAN ROBERT H. , VINETZ JOSEPH M.
Published: September 2018

The role of bats as potential sources of transmission to humans or as maintenance hosts of leptospires is poorly understood. We quantified the prevalence of leptospiral colonization in bats in the Peruvian Amazon in the vicinity of Iquitos, an area of high biologic diversity. Of 589 analyzed bats, culture (3 of 589) and molecular evidence (20 of 589) of leptospiral colonization was found in the kidneys, yielding an overall colonization rate of 3.4%. Infection rates differed with habitat and location, and among different bat species. Bayesian analysis was used to infer phylogenic relationships of leptospiral 16S ribosomal DNA sequences. Tree topologies were consistent with groupings based on DNA-DNA hybridization studies. A diverse group of leptospires was found in peri-Iquitos bat populations including Leptospira interrogans (5 clones), L. kirschneri (1), L. borgpetersenii (4), L. fainei (1), and two previously undescribed leptospiral species (8). Although L. kirschenri and L. interrogans have been previously isolated from bats, this report is the first to describe L. borgpetersenii and L. fainei infection of bats. A wild animal reservoir of L. fainei has not been previously described. The detection in bats of the L. interrogans serovar Icterohemorrhagiae, a leptospire typically maintained by peridomestic rats, suggests a rodent-bat infection cycle. Bats in Iquitos maintain a genetically diverse group of leptospires. These results provide a solid basis for pursuing molecular epidemiologic studies of bat-associated Leptospira, a potentially new epidemiologic reservoir of transmission of leptospirosis to humans.
IDENTIFICATION AND CHARACTERIZATION OF SARCOPTES SCABIEI AND DERMATOPHAGOIDES PTERONYSSINUS GLUTATHIONE S-TRANSFERASES: IMPLICATION AS A POTENTIAL MAJOR ALLERGEN IN CRUSTED SCABIES
Authors: DOUGALL ANNETTE , HOLT DEBORAH C. , FISCHER KATJA , CURRIE BART J. , KEMP DAVID J. , WALTON SHELLEY F.
Published: September 2018

The astigmatid mite Sarcoptes scabiei is the causative agent of scabies, a highly infectious parasitic disease of the skin. Although the mite causes marked hypersensitivity reactions, particularly in crusted (severe) scabies, little is known about the specific scabies mite molecules involved in such immunologic responses. We have identified six genes encoding scabies mite homologues of mu and delta-like glutathione S-transferases (GSTs) as well as novel house dust mite GSTs. A mu class S. scabiei GST was subcloned into a prokaryotic expression system. The purified recombinant protein rSsGST01 reacted strongly with IgE and IgG4 in sera from crusted scabies patients. This response was not observed with control antigens or with ordinary scabies and uninfested patient sera. In addition, the specific IgE response to rSsGST01 did not correlate with the total IgE level of the patient. These results suggest that GST may play a role in the pathophysiology associated with crusted scabies.
NATURAL COURSE OF LYMPHATIC FILARIASIS: INSIGHTS FROM EPIDEMIOLOGY, EXPERIMENTAL HUMAN INFECTIONS, AND CLINICAL OBSERVATIONS
Authors: RAJAN T. V.
Published: September 2018

Lymphatic filariasis has been described as a “spectral disease”. Analysis of the natural course of infection in nonendemic individuals as well as experimental infections of “volunteers” suggests that the filarial parasites are not inherently aggressive infectious agents. Experimental infections of humans with infective larvae result in transient, low-level microfilaremia, if at all. Nonendemic individuals with limited exposure show no evidence of persistent infection or pathology. Nonendemic individuals exposed to repeated infections show accelerated pathology. It is tempting to speculate that normal, immunocompetent residents in an endemic area show either (a) no pathology (endemic normals) because they are subject to the relatively low levels of infection or (b) chronic pathology if they are repeatedly infected. It would appear that only those individuals rendered immunologically tolerant to filarial parasites become productively infected with the filarial parasites. The intensity of transmission may underlie the differences in clinical presentation seen in diverse global pockets of endemicity.
VERIFIED BITES BY YELLOW SAC SPIDERS (GENUS CHEIRACANTHIUM) IN THE UNITED STATES AND AUSTRALIA: WHERE IS THE NECROSIS?
Authors: VETTER RICHARD S. , ISBISTER GEOFFREY K. , BUSH SEAN P. , BOUTIN LISA J.
Published: September 2018

Spiders of the genus Cheiracanthium are frequently reported in review articles and medical references to be a definitive cause of dermonecrosis or necrotic arachnidism in humans. We provide 20 cases of verified bites by Cheiracanthium spiders from the United States and Australia, none with necrosis. A review of the international literature on 39 verified Cheiracanthium bites found only one case of mild necrosis in the European species C. punctorium. The basis for the suggestion that this spider genus causes dermonecrosis seems to be mostly inference from venom experiments in rabbits and guinea pigs, circumstantial spider involvement in human skin lesions, and repetitive citation of non-definitive reports in the medical literature. We discuss factors that lead to the erroneous elevation of virtually innocuous spiders to that of significant medical concern, which is a recurring problem in the medical community.
DISSEMINATION OF SALMONELLA ENTERICA SEROTYPE AGONA AND MULTIDRUG-RESISTANT SALMONELLA ENTERICA SEROTYPE TYPHIMURIUM IN CUBA
Authors: CABRERA ROBERTO , RUIZ JOAQUIM , RAMÍREZ MARGARITA , BRAVO LAURA , FERNÁNDEZ ANABEL , ALADUEÑA ANA , ECHEÍTA AURORA , GASCÓN JOAQUIM , ALONSO PEDRO L. , VILA JORDI
Published: September 2018

The molecular epidemiology, antimicrobial susceptibility, and mechanisms of resistance of 34 Salmonella spp. strains causing acute gastroenteritis, isolated from different provinces in Cuba, were determined. Sixty-four percent of the strains showed multiresistance. Salmonella typhimurium was the most frequent with 15 strains (44%), 13 of which belonged to phagotype 104 and presented similar genetic profiles of pulsed field gel electrophoresis. High levels of resistance to tetracycline (53%), spectinomycin (50%), ampicillin (44%), and chloramphenicol (41%) were found. Resistance to tetracycline was associated with the tet G and tet A genes. Resistance to ampicillin was caused by the presence of β-lactamases, mainly the CARB type. The floR gene was the main mechanism of resistance to chloramphenicol. Our results showed an antimicrobial susceptible clone of Salmonella enterica serotype Agona in two separate regions. This is the first report of the widespread dissemination of a multiresistant clone of S. enterica serotype Typhimurium definitive phage type 104 in Cuba.
SEROPREVALENCE AND RISK FACTORS FOR HEPATITIS C VIRUS INFECTION AMONG FEMALE COMMERCIAL SEX WORKERS IN SOUTH KOREA WHO ARE NOT INTRAVENOUS DRUG USERS
Authors: KWEON SUN-SEOG , SHIN MIN-HO , SONG HYEON-JE , JEON DOO-YOUNG , CHOI JIN-SU
Published: September 2018

Several previous studies have reported a high prevalence of hepatitis C virus (HCV) infection among commercial sex workers (CSWs), but the situation is often compounded by coexisting factors, such as intravenous drug use. We conducted a seroepidemiologic study of 1,527 female CSWs in South Korea. All participants tested negative for human immunodeficiency virus and were not illicit intravenous drug users (IDUs). Twenty-one participants (1.4%) were positive for antibodies to HCV. According to the multivariate logistic regression analysis, a history of acupuncture and diabetes mellitus were associated with the seroprevalence of HCV, whereas time spent as a CSW showed only borderline significance. Sexual activity was not an independent predictor of increased risk for HCV infection in female CSWs who had never been illicit IDUs.
FIRST DETECTION OF RICKETTSIA FELIS IN CTENOCEPHALIDES FELIS FLEAS PARASITIZING RATS IN CYPRUS
Authors: PSAROULAKI ANNA , ANTONIOU MARIA , PAPAEUSTATHIOU ANDREAS , TOUMAZOS PAUL , LOUKAIDES FEIDIAS , TSELENTIS YANNIS
Published: September 2018

Rickettsia felis was identified by polymerase chain reaction amplification and DNA sequencing analysis in Ctenocephalides felis fleas parasitizing rats in Cyprus. Murine typhus caused by R. typhi was believed to be the only flea-transmitted rickettsiosis on the island. This is the first report of this pathogen in southeastern Europe.
QUANTITATIVE ANALYSIS OF DENGUE-2 VIRUS RNA DURING THE EXTRINSIC INCUBATION PERIOD IN INDIVIDUAL AEDES AEGYPTI
Authors: RICHARDSON JASON , MOLINA-CRUZ ALVARO , SALAZAR MA ISABEL , BLACK WILLIAM
Published: September 2018

Dengue virus-2 (DENV-2) RNA was quantified from the midgut and legs of individual Aedes aegypti at each of 14 days postinfectious blood meal (dpi) in a DENV-2 susceptible strain from Chetumal, Mexico. A SYBR Green I based strand-specific, quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) assay was developed. The lower detection and quantitation limits were 20 and 200 copies per reaction, respectively. Amounts of positive and negative strand viral RNA strands were correlated. Numbers of plaque-forming units (PFU) were correlated with DENV-2 RNA copy number in both C6/36 cell cultures and mosquitoes. PFU were consistently lower than RNA copy number by 2–3 log10. Midgut levels of DENV-2 RNA peaked 8 dpi and fluctuated erratically between 6 and 9 dpi. Copies of DENV-2 RNA varied significantly among infected mosquitoes at each time point. Quantitative real-time RT-PCR is a convenient and reliable method that provides new insights into virus-vector interactions.
RESPIRATORY SYNCYTIAL VIRUS INFECTIONS IN NORTHEASTERN BRAZIL: SEASONAL TRENDS AND GENERAL ASPECTS
Authors: MOURA FERNANDA E. A. , NUNES ILA F. S. , SILVA GERALDO B. , SIQUEIRA MARILDA M.
Published: September 2018

Respiratory syncytial virus (RSV) is one of the most prevalent agents of acute respiratory infections in children. Consistent data about seasonality of infections caused by this virus in Brazil proceed only from southern and southeastern regions. The purpose of this study was to determine the prevalence and the seasonal pattern of RSV infections in children living in Fortaleza city in northeastern Brazil. Nasopharyngeal aspirates of 1,950 patients attending in ambulatories, emergency room, and wards of Hospital Infantil Albert Sabin were collected and screened for RSV infections during 43 consecutive months. RSV was detected in 21% of the cases. RSV seasons in Fortaleza lasted 6 to 8 consecutive months, starting in January or February and finishing in July or August, and were associated with the rainy season.
CHANGES IN SEROPREVALENCE OF WEST NILE VIRUS ACROSS ILLINOIS IN FREE-RANGING BIRDS FROM 2001 THROUGH 2004
Authors: BEVEROTH TARA A. , WARD MICHAEL P. , LAMPMAN RICHARD L. , RINGIA ADAM M. , NOVAK ROBERT J.
Published: September 2018

Of the 5,236 birds sampled for antibodies to West Nile virus (WNV) in Illinois from 2001 through 2004, 348 (6.6%) birds were seropositive. Our multiple year surveillance identified several avian species that had particularly high percentages of seropositive individuals. The importance of these species in the enzootic and/or epizootic transmission of WNV is discussed relative to their regional abundance and literature on host competency. The species with the highest exposure rates to WNV differed both temporally and regionally. In general, birds that bred or were born in Illinois were more likely to have antibodies than transient birds. There was also a significant difference in the seroprevalence between adults (12.1%) and juveniles (5.5%), indicating that the acquired antibody response from previous years is a critical concern when interpreting seroprevalence rates in wild-caught birds. The most common hosts for St. Louis encephalitis virus were also the most common hosts for WNV, which strongly supports the role of similar vectors for both flaviviruses. Avian species with high WNV seroprevalence rates tended to be those that bred throughout the year, have open cup nests, and live in close proximity to humans.
SUCCESSFUL TREATMENT OF PLASMODIUM FALCIPARUM MALARIA WITH A SIX-DOSE REGIMEN OF ARTEMETHER-LUMEFANTRINE VERSUS QUININE-DOXYCYCLINE IN THE WESTERN AMAZON REGION OF BRAZIL
Authors: ALECRIM MARIA G. , LACERDA MARCUS V. , MOURÃO MARIA P. , ALECRIM WILSON D. , PADILHA ALEXANDRE , CARDOSO BERNARDO S. , BOULOS MARCOS
Published: September 2018

This randomized, open-label study compared a three-day, six-dose regimen of artemether-lumefantrine with a five-day, 19-dose regimen of quinine-doxycycline for the treatment of Plasmodium falciparum malaria in the western Amazon region of Brazil. All patients remained hospitalized during their treatment and the study assessments were scheduled daily from the start of treatment (day 0) through day 6. By day 3, the percentage of infected patients was 0% in the artemether-lumefantrine group and 48.8% in the quinine-doxycycline group. Median parasite clearance time was significantly shorter in the artemether-lumefantrine group (two days) compared with the quinine-doxycycline group (three days) (P < 0.0001). Two patients in the quinine-doxycycline group left the study early because of treatment ineffectiveness or adverse event. Adverse events were reported by 91.5% of the study participants, most of which were mild in severity and/or not considered related to study treatment. Artemether-lumefantrine was shown to be an efficacious, safe, and convenient treatment for P. falciparum malaria in a highly drug-resistant region of South America.
FREQUENCY DISTRIBUTION OF ANTIMALARIAL DRUG-RESISTANT ALLELES AMONG ISOLATES OF PLASMODIUM FALCIPARUM IN BANGUI, CENTRAL AFRICAN REPUBLIC
Authors: MENARD DIDIER , DJALLE DJIBRINE , YAPOU FERDINAND , MANIRAKIZA ALEXANDRE , TALARMIN ANTOINE
Published: September 2018

We determined the baseline frequency distribution of mutant alleles of genes associated with resistance to chloroquine and sulfadoxine-pyrimethamine in Plasmodium falciparum isolates in Bangui, Central African Republic. Mutant alleles of the P. falciparum chloroquine resistance transporter (pfcrt) gene were found in all samples and the frequency of the deduced CIET pfcrt haplotype was high (45%). The most common allele of the P. falciparum multidrug resistance 1 (pfmdr1) gene among the field isolates of P. falciparum was 86Y (21.9%). The 1246Y allele was also common (18.0%). Of the 167 P. falciparum isolates in which the dihydrofolate reductase gene was studied, only 11 carried the wild-type allele (6.6%) whereas many (50.3%) were quadruple mutants (50R, 51I, 59R, 108N). The frequency of the 436A mutant allele of the dihydropteroate synthase gene was high (74.3%), but the frequencies of the 437G (18.6%) and 540E (5.2%) mutant alleles were low. Molecular analyses of antimalarial drug-resistant alleles of P. falciparum isolates in Bangui strongly suggest the widespread distribution of chloroquine and pyrimethamine resistance and to a lesser extent sulfadoxine resistance.
MORBIDITY AND MORTALITY PROFILE OF HUMAN IMMUNODEFICIENCY VIRUS–INFECTED PATIENTS WITH AND WITHOUT HEPATITIS C CO-INFECTION
Authors: MAYOR ANGEL M. , GOMEZ MARIA A. , FERNANDEZ DIANA M. , RIOS-OLIVARES EDDY , THOMAS JAMES C. , HUNTER ROBERT F.
Published: September 2018

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection is an important and frequent scenario, predominantly in injecting drug users (IDUs). The present study evaluated morbidity and mortality variation in HIV-infected patients with and without HCV co-infection. Co-infection prevalence was determined in 356 HIV-infected persons. Their clinical manifestations, laboratory findings, risk factors, HIV therapies, and mortality rates were evaluated. The prevalence of HCV was 54% in the overall group and 81% in IDUs, with a predominance of HCV genotype 1. Mortality rates were similar in patients with and without co-infection; however, co-infected patients had significantly higher liver damage as a cause of mortality when compared with those who were not co-infected. The high prevalence of HCV and an emerging mortality from liver diseases showed the significance of this co-infection in the HIV epidemic. Primary and secondary prevention are necessary to reduce the expanding impact of HCV infection in HIV patients.
IMPAIRMENT OF HOST IMMUNE RESPONSE AGAINST STRONGYLOIDES STERCORALIS BY HUMAN T CELL LYMPHOTROPIC VIRUS TYPE 1 INFECTION
Authors: HIRATA TETSUO , UCHIMA NOBUFUMI , KISHIMOTO KAZUTO , ZAHA OSAMU , KINJO NAGISA , HOKAMA AKIRA , SAKUGAWA HIROSHI , KINJO FUKUNORI , FUJITA JIRO
Published: September 2018

A large-scale study was undertaken to clarify the prevalence rate of strongyloidiasis in Okinawa, Japan and to evaluate the relationship between strongyloidiasis and infection with human T cell lymphotropic virus type 1 (HTLV-1). The prevalence rate of Strongyloides stercoralis and HTLV-1 infection were 6.3% and 14.0%, respectively. Among 2,185 patients more than 50 years of age, the rate of S. stercoralis infection was significantly higher in patients with HTLV-1 infection compared with patients without HTLV-1 infection. In 252 patients treated with ivermectin, serum IgE levels and peripheral eosinophil counts were significantly lower in HTLV-1 co-infected patients compared with patients without HTLV-1 infection. In addition, the anthelmintic effect was significantly lower in patients with HTLV-1 infection compared with patients without HTLV-1 infection. Our prospective study demonstrated a prevalence rate for strongyloidiasis and HTLV-1 infections, and clearly demonstrated that co-infection with HTLV-1 impaired the immune response against S. stercoralis.
ASSOCIATION OF HAPTOGLOBIN LEVELS WITH AGE, PARASITE DENSITY, AND HAPTOGLOBIN GENOTYPE IN A MALARIA-ENDEMIC AREA OF GABON
Authors: FOWKES FREYA J. I. , IMRIE HEATHER , MIGOT-NABIAS FLORENCE , MICHON PASCAL , JUSTICE ANITA , DELORON PHILLIPE , LUTY ADRIAN J. F. , DAY KAREN P.
Published: September 2018

Haptoglobin (Hp) levels were investigated in relation to host genotype in a malaria-endemic area in Gabon. A cross-sectional study of 1–12-year-old children was conducted in the rainy season, a period of high malaria transmission, to examine this relationship. Variables that influenced Hp levels were Hp genotype, location, and age interacting with parasite density. At low parasite densities, there was a negative correlation between Hp levels and age. At higher densities, there was a positive correlation with age. This suggests that in the presence of greater parasite-induced hemolysis, older children are capable of increased production of Hp. Sickle cell trait and ABO blood group was not associated with Hp levels in this population.
INDUCTION OF NEUTRALIZING ANTIBODIES SPECIFIC TO DENGUE VIRUS SEROTYPES 2 AND 4 BY A BIVALENT ANTIGEN COMPOSED OF LINKED ENVELOPE DOMAINS III OF THESE TWO SEROTYPES
Authors: KHANAM SAIMA , ETEMAD BEHZAD , KHANNA NAVIN , SWAMINATHAN SATHYAMANGALAM
Published: September 2018

There is no vaccine to prevent dengue fever, a mosquito-borne viral disease, caused by four serotypes of dengue viruses. In this study, which has been prompted by the emergence of dengue virus envelope domain III as a promising sub-unit vaccine candidate, we have examined the possibility of developing a chimeric bivalent antigen with the potential to elicit neutralizing antibodies against two serotypes simultaneously. We created a chimeric dengue antigen by splicing envelope domain IIIs of serotypes 2 and 4. It was expressed in Escherichia coli and purified to near homogeneity. This protein retains the antigenic identitities of both its precursors. It elicited antibodies that could efficiently block host cell binding of both serotypes 2 and 4 of dengue virus and neutralize their infectivity (neutralizing antibody titers approximately 1:40 and ~1:80 for dengue virus serotypes 2 and 4, respectively). This work could be a forerunner to the development of a single envelope domain III-based tetravalent antigen.
LEISHMANIA TROPICA–ISOLATED PATIENT WITH VISCERAL LEISHMANIASIS IN SOUTHERN IRAN
Authors: ALBORZI ABDOLVAHAB , RASOULI MANOOCHEHR , SHAMSIZADEH AHMAD
Published: September 2018

Visceral leishmaniasis (VL) is caused by various strains of Leishmania donovani, Leishmania infantum, and Leishmania chagasi with different geographical distribution. The aim of this study was to identify the strains of Leishmania that can cause VL in southern Iran. DNA of Leishmania were extracted from the slides of bone marrow aspirates (#42) and spleen punctures (#22), which were positive for leishman body from the patients who were referred to the hospitals affiliated with Shiraz University of Medical Sciences. Differences in Leishmania strains were determined by size difference of the polymerase chain reaction (PCR) amplification as visualized on agarose gel. PCR results and smears had 100% correlation. The dominant strain of Leishmania was L. infantum (63 out of the 64 cases), but one case of L. tropica was also detected. VL mostly involves children below 2 years of age in Iran, therefore infection with L. infantum was expected, but this study is the first report of VL that is caused by L. tropica in Iran.
LIMITED ALLELIC DIVERSITY OF PLASMODIUM FALCIPARUM MEROZOITE SURFACE PROTEIN 1 GENE FROM POPULATIONS IN THE SOLOMON ISLANDS
Authors: SAKIHAMA NAOKO , OHMAE HIROSHI , BAKOTE’E BERNARD , KAWABATA MASATO , HIRAYAMA KENJI , TANABE KAZUYUKI
Published: September 2018

Meiotic recombination generates allelic diversity in the Plasmodium falciparum merozoite surface protein 1 (msp1) gene. In this study, we monitored recombination-based diversity of msp1 in Guadalcanal, the Solomon Islands, where malaria transmission is high. We identified 5′ recombinant types, 3′ sequence types, and msp1 haplotypes (unique associations of 5′ recombinant types and 3′ sequence types), and compared them with those from areas of low transmission in Thailand and Vanuatu. The mean number of 5′ recombinant types per person (multiplicity) was lower in Guadalcanal than in Thailand. Guadalcanal populations had 6–8 msp1 haplotypes; the numbers are comparable to Vanuatu but much lower than in Thailand. There were marked geographic differences in distribution of msp1 haplo-types. Linkage disequilibrium in msp1 was stronger in Guadalcanal than in Thailand, suggesting limited recombination events in the Solomon Islands. We suggest that the frequency of recombination events in msp1 is determined not only by transmission intensity but by the number of msp1 alleles prevalent and multiplicity of infections.
PREVALENCE OF CRYPTOSPORIDIUM AND OTHER ENTERIC PARASITES AMONG WILD NON-HUMAN PRIMATES IN POLONNARUWA, SRI LANKA
Authors: EKANAYAKE DILRUKSHI K. , ARULKANTHAN APPUDURAI , HORADAGODA NEIL U. , SANJEEVANI G. K. MADURA , KIEFT RUDO , GUNATILAKE SUNIL , DITTUS WOLFGANG P. J.
Published: September 2018

Cryptosporidiosis is a rapidly emerging disease in the tropics. This is the first report of Cryptosporidium and other protozoan infections (Entamoeba spp., Iodamoeba, Chilomastix, and Balantidium spp.) in wild primates that inhabit the natural forest of Sri Lanka. It is unclear if non-human primates serve as a reservoir for these parasites under certain conditions. A cross-sectional coprologic survey among 125 monkeys (89 toque macaques, 21 gray langurs, and 15 purple-faced langurs) indicated that Cryptosporidium was detected in all three primate species and was most common among monkeys using areas and water that had been heavily soiled by human feces and livestock. Most macaques (96%) shedding Cryptosporidium oocysts were co-infected with other protozoans and important anthropozoonotic gastrointestinal parasites (e.g., Enterobius and Strongyloides). The transmission of these parasites among primates in the wild may have important implications for public health as well as wildlife conservation management.
A DRUG-BASED INTERVENTION STUDY ON THE IMPORTANCE OF BUFFALOES FOR HUMAN SCHISTOSOMA JAPONICUM INFECTION AROUND POYANG LAKE, PEOPLE’S REPUBLIC OF CHINA
Authors: GUO JIAGANG , LI YUESHENG , GRAY DARREN , NING AN , HU GUANGHAN , CHEN HONGGEN , DAVIS GEORGE M. , SLEIGH ADRIAN C. , FENG ZHENG , McMANUS DONALD P. , WILLIAMS GAIL M.
Published: September 2018

Schistosomiasis japonica is a zoonosis of major public health importance in southern China. We undertook a drug intervention to test the hypothesis that buffalo are major reservoirs for human infection in the marshlands/lake areas, where one million people are infected. We compared human and buffalo infection rates and intensity in an intervention village (Jishan), where humans and buffalo were treated with praziquantel, and a control village (Hexi), where only humans were treated, in the Poyang Lake region. Over the four-year study, human incidence in Jishan decreased but increased in Hexi. Adjustment of incidence by age, sex, water exposure, year, and village further confirmed the decreased human infection in Jishan. Chemotherapy for buffaloes resulted in a decrease in buffalo infection rates in Jishan, which coincided with the reduction in human infection rates there in the last two years of the study. Mathematical modeling predicted that buffalo are responsible for 75% of human transmission in Jishan.
EFFICACY OF SULFADOXINE-PYRIMETHAMINE IN THE TREATMENT OF UNCOMPLICATED PLASMODIUM FALCIPARUM MALARIA IN EAST TIMOR
Authors: BURNS MATTHEW , BAKER JOANNE , AULIFF ALYSON M. , GATTON MICHELLE L. , EDSTEIN MICHAEL D. , CHENG QIN
Published: September 2018

The efficacy of sulfadoxine-pyrimethamine (SP) in East Timor is unknown. We treated 38 individuals with uncomplicated Plasmodium falciparum malaria with SP and monitored the outcome for 28 days. Recrudescent parasitemia, confirmed by genotyping, were detected in three individuals resulting in a late treatment failure rate of 7.9% (95% confidence interval = 1.7–21.4%). The results suggest that SP is still efficacious in treating uncomplicated P. falciparum malaria in East Timor. However, the useful life of SP in East Timor may be limited because 80% of the parasites in our samples were found to already carry double mutations in P. falciparum dihydrofolate reductase (S108N/C59R). The data from this study also highlights that the presence of gametocytes may significantly influence the estimate of SP efficacy determined by genotyping.
POPULATION STRUCTURE ANALYSIS OF PLASMODIUM VIVAX IN AREAS OF IRAN WITH DIFFERENT MALARIA ENDEMICITY
Authors: ZAKERI SEDIGHEH , MEHRIZI AKRAM ABOUIE , MAMAGHANI SHADI , NOORIZADEH SOMAYYEH , SNOUNOU GEORGES , DJADID NAVID DINPARAST
Published: September 2018

To obtain the genetic structure of Plasmodium vivax populations in the northern and southern malaria-endemic areas in Iran, which differ in endemicity, sequence diversity in the variable block 5 and the C-terminal part of P. vivax merozoite surface protein 1 (Pvmsp 1) was analyzed. The variable block 5 fragment from 52 northern and 94 southern isolates was amplified and sequenced. Type 1, type 2, and recombinant type 3 allelic variants were found in both northern and southern isolates, with type 1 predominant in parasites from the north and type 2 in those from the south. A total of 7 and 27 distinct variants were detected among northern and southern isolates, respectively. A single variant predominated (71%) in the northern isolates, whereas variants were evenly distributed among southern isolates, with only two exceeding 10%. Thus, parasites from the southern malaria-endemic area were more polymorphic than those circulating in the northern area, where malaria is a re-emerging disease. Sequence alignments showed that although some variants were found only in northern or southern isolates, some were common to both and had also been observed in parasites from Azerbaijan, Turkey, Thailand, Bangladesh, and China. The Pvmsp 1 fragment corresponding to the C-terminal region was also amplified and the sequences derived from 20 northern and 50 southern isolates were identical. This high degree of conservation reinforces the potential of this polypeptide fragment for inclusion in synthetic vaccines being developed against P. vivax.