bluuebunny/crossref_metadata_2025 huggingface dataset:
Socioeconomic implications of Buruli ulcer in Ghana: a three-year review.
Authors: Asiedu K , Etuaful S
Published: May 2017

This study examines some of the socioeconomic cost of treating 102 cases of Buruli ulcer between 1994 and 1996 at the St. Martin's Catholic Hospital in Agroyesum in the Amansie West district of the Ashanti region of Ghana. Seventy percent of the cases were children (up to 15 years of age). There was no sex difference in the distribution of cases. Hospitalization was prolonged (average = 186 days in 1994, 103 days in 1995, and 102 days in 1996) with no significant age and sex differences. There were 10 limb amputations, 12 patients were left with contracture deformities, one patient lost sight in one eye, and two died of sepsis and tetanus. The average total treatment cost per patient was $966.85 (62% indirect) in 1994, $706.08 (75% indirect) in 1995, and $658.74 (79% indirect) in 1996. With increasing number of cases, high treatment costs, and serious complications, urgent attention should be given to the disease in terms of control and research efforts aimed at early detection and treatment.
Trypanosoma cruzi in the rectum of the bug Triatoma infestans: effects of blood ingestion by the starved vector.
Authors: Kollien A H , Schaub G A
Published: May 2017

To follow the developmental effects of feeding of the insect host after long starvation periods, the population density and composition of an established infection of Trypanosoma cruzi in the rectum of Triatoma infestans were determined 60 days after the last feeding (daf) and then at different intervals after feeding. The original population decreased and then increased up to the 10th daf. In starved bugs, about 30% were spheromastigotes (including intermediate forms), 20% epimastigotes, and 50% trypomastigotes, but one daf, these forms represented 2%, 70%, and 10%, respectively. In addition, one daf there were about 10% giant cells, i.e., a multiple division stage. In the following two days, this form represented on average 30-50% of the total population, but it then disappeared nearly completely. Thus, giant cells evidently develop by rapid growth of epimastigotes, if conditions become optimal after long starvation periods of the vector.
Mixed infection of human U-937 cells by two different species of Leishmania.
Authors: Abdullah S M , Flath B , Presber W
Published: May 2017

Mixed infections by different Leishmania species could explain differences in the clinical course of these infections. Moreover, mixed infections of the same macrophage could be the basis for parasite recombination. We stained three strains of Leishmania (L. mexicana amazonensis, L. donovani DD8, and L. infantum D2, respectively) with different fluorescent dyes and analyzed them using a fluorescence-activated cell scanner. The simultaneous infection of one cell by Leishmania belonging to two different species was demonstrated. In additional experiments, cells with mixed infections were separated by a fluorescence-activated cell sorter and monitored for 24 hr. Preinfecting human monocytic U-937 cells with one Leishmania species did not exclude a second species added after 3 hr.
The time course of cytoadhesion, immunoglobulin binding, rosette formation, and serum-induced agglutination of Plasmodium falciparum-infected erythrocytes.
Authors: Treutiger C J , Carlson J , Scholander C , Wahlgren M
Published: May 2017

We describe morphologic characteristics of acridine orange-stained Plasmodium falciparum-infected erythrocytes and the sequential expression of several adhesion phenomena. In particular, we have studied when the adhesive and antigenic modifications appear on the infected erythrocyte surface that mediate binding to C32 melanoma cells (cytoadherence) or to erythrocytes (rosette formation) during a complete 48-hr life cycle of the parasite. The C32 melanoma cell binding started at about 12 hr and was seen during the whole life cycle with a peak around 28 hr (650 infected erythrocytes/100 C32 melanoma cells). Rosettes started to appear and immunoglobulin was found bound to the parasitized red blood cell (PRBC) somewhat later (16-20 hr). These adhesive events culminated at the mid-trophozoite/schizont stage (24-36 hr) with rosette formation and an immunoglobulin binding rate of about 50%, which decreased to about half of the peak values at the end of the life cycle. Serum-induced agglutination of the infected erythrocytes was also most extensive at 24-36 hr, but agglutination was seen with all late stage parasites, i.e., both trophozoites and schizonts at 24-48 hr of age. Taken together, adhesion to C32 melanoma cells starts prior to that of rosette formation, immunoglobulin binding, or serum-induced agglutination.
Lymphatic filariasis in a hyperendemic region: a ten-year, follow-up panel survey.
Authors: Myung K , Massougbodji A , Ekoue S , Atchade P , Kiki-Fagla V , Klion A D
Published: May 2017

The present study is a long-term panel survey of a population living in a previously identified Wuchereria bancrofti-endemic area of Benin. Unexpectedly, a marked decrease in the prevalence of microfilaremia (from 9.4% to 0.48%; P < 0.001) occurred over a 10-year period in the absence of chemotherapy or vector control measures. The percentage of patients with chronic pathology remained stable during the study period. The decrease in the prevalence of parasitemia could not be explained by environmental or sociologic changes in the region, or by differences between the two study populations. These data suggest that the epidemiology of lymphatic filariasis in an endemic region may change independently of recognized modulating factors.
Prevalence of rhinosporidiosis of the eye and its adnexa in Nepal.
Authors: Shrestha S P , Hennig A , Parija S C
Published: May 2017

This study describes the clinical features, diagnosis, and treatment of rhinosporidiosis of the eye and its adnexa in a series of 76 cases in Nepal and six originating in India. The disease caused by the fungus Rhinosporidium seeberi was seen most frequently in young children between eight and 10 years of age. Males were infected more than females (2.5:1). The conjunctiva was the most common site of infection in 76 (92.68%) of the cases. The lacrimal sac was affected only in six (7.32%) cases. Simple total excision of the conjunctival polyps gave highly satisfactory results in cases of conjunctival sac infections. Except for one patient, there were no recurrences in the 76 cases. Meticulous excision of polyps provided a satisfactory result in the treatment of six cases with lacrimal sac infection. Recurrence was noted in one of these six cases followed up to two and a half years after surgery. The conditions diagnosed clinically were confirmed by histopathology. This review of 82 cases is the first such report of rhinosporidiosis from Nepal.
Incidence of Plasmodium falciparum infection in infants in relation to exposure to sporozoite-infected anophelines.
Authors: Charlwood J D , Smith T , Lyimo E , Kitua A Y , Masanja H , Booth M , Alonso P L , Tanner M
Published: May 2017

The relationship of the incidence of Plasmodium falciparum infection to entomologic inoculation rates (EIRs) was studied in 163 children less than one year of age in a Tanzanian village to determine likely effects of transmission-reducing interventions on infection incidence. A total of 66,727 Anopheles gambiae s.l. and 17,620 An. funestus mosquitoes were caught in 1,056 light trap collections from 139 houses over a period of more than two years. Time period-specific human biting rates were estimated for 11 village neighborhoods. Sporozoites were detected by ELISA in 4.4% of the An. funestus and 2.5% of the An. gambiae s.l. Eight hundred seventeen pairs of blood slides with approximately two-week intervals between slides were used to estimate incidence of parasitemia by fitting reversible catalytic models to parasite positivity data. Estimated EIRs during the four weeks preceding each intersurvey interval averaged 1.6 (SD = 2.1) per adult per night. Parasites were present at the end of 31% of the 443 intervals that commenced with a parasite-negative slide. Attack rates were comparable with those in western Kenya, and the proportion of bites resulting in human infections was strongly dependent on mosquito density. Incidence of infection increased with the EIR up to approximately one bite from a sporozoite-carrying mosquito per adult per night. However, higher levels of transmission observed locally in the wet season did not result in a correspondingly higher incidence. These data suggest that transmission-reducing measures cannot be expected to reduce incidence of infection at the highest levels of EIR.
Detection of hepatitis B surface antigen in pregnant women attending a public hospital for delivery: implication for vaccination strategy in Bangladesh.
Authors: Rumi M A , Begum K , Hassan M S , Hasan S M , Azam M G , Hasan K N , Shirin M , Khan A K
Published: May 2017

Routine antenatal hepatitis B surface antigen (HBsAg) screening and immunization of risk babies is very effective in preventing perinatal transmission of hepatitis B virus (HBV). We studied 1,800 parturients attending a public hospital to assess the rationale for such vaccination in Bangladesh. In one in every 29 deliveries (63 of 1,800 or 3.5%), the mother was found to be HBsAg positive. All were asymptomatic and many (41 of 63 or 65%) without risk factors would remain undetected if HBsAg screening were performed on selected groups. Most of the HBsAg-positive mothers (54 of 63 or 85.7%) were found to be chronic carriers and 30.2% (19 of 63) were also hepatitis B e antigen (HBeAg) positive, indicating high infectivity. Although 23 cord blood were positive for HBsAg or HBeAg, none were positive for IgM antibody to hepatitis B core antigen (IgM anti-HBc), suggesting transplacental transmission of the antigens rather than intrauterine infection. These findings are discussed in relation to the cost-effectiveness of routine prenatal screening and immunization of risk babies compared with universal infant immunization.
Baseline immunity of the population and impact of insecticide-treated curtains on malaria infection.
Authors: Modiano D , Petrarca V , Sirima B S , NebiÃ© I , Luoni G , Esposito F , Coluzzi M
Published: May 2017

It has been shown that insecticide-treated bed nets or curtains may reduce morbidity and mortality from malaria in hyper-holoendemic areas of sub-Saharan Africa. This protection could partially depend on the transitory imbalance between the anti-malaria immunity acquired by the population before the intervention and the lowered sporozoite load resulting from the anti-vector measure. To verify if the efficacy of the intervention is influenced by the baseline immune status of the population, we compared the protective effect of permethrin-impregnated curtains (PIC) against malaria infection among groups with different baseline levels of anti-malaria immunity. We analyzed the impact of PIC on the Plasmodium falciparum infection rate in two rural villages of Burkina Faso inhabited by three ethnic groups: the Fulani, Mossi, and RimaibÃ©. These have been previously shown to differ for several malariologic indices, with the Fulani being characterized by lower infection and disease rates and by higher immune response to P. falciparum with respect to the other ethnic groups. The PIC were distributed in June 1996 and their impact on malaria infection was evaluated in groups whose baseline levels of immunity to malaria differed because of their age and ethnic group. Age- and ethnic-dependent efficacy of the PIC was observed. Among the Mossi and RimaibÃ©, the impact (parasite rate reduction after PIC installation with respect to the pre-intervention surveys) was 18.8% and 18.5%, respectively. A more than two-fold general impact (42.8%) was recorded in the Fulani. The impact of the intervention on infection rates appears positively correlated with the levels of anti-malaria immunity. Since decreased transmission entails a reduction of immunity, the efficacy of the intervention in the long term cannot be taken for granted. The expected complementary role of a hypothetical vaccine is stressed by these results, which also emphasize the importance of the genetic background of the population in the evaluation and application of malaria control strategies.
Use of antimalarial drugs in Mali: policy versus reality.
Authors: Djimde A , Plowe C V , Diop S , Dicko A , Wellems T E , Doumbo O
Published: May 2017

Inappropriate use of antimalarial drugs undermines therapeutic efficacy and promotes the emergence and spread of drug-resistant malaria. Strategies for improving compliance require accurate information about current practices. Here we describe Knowledge-Attitude-Practice surveys conducted among health providers and consumers in two Malian villages, one rural and one periurban. All sanctioned providers limited their first choices of antimalarial drug to those recommended by the national malaria control program and reported using correct dosing regimens. However, the majority of consumers in the two villages chose non-recommended treatments for malaria and reported suboptimal treatment regimens when they did use recommended drugs. Antimalarial drugs were also widely available from unsanctioned sources, often accompanied by erroneous advice on dosing regimens. This study demonstrates that even when the most peripheral health providers are well-trained in correct use of antimalarial drugs, additional measures directly targeting consumers will be required to improve drug use practices.
Human immunodeficiency virus-associated diarrhea and wasting in Zambia: selected risk factors and clinical associations.
Authors: Chintu C , Dupont H L , Kaile T , Mahmoud M , Marani S , Baboo K S , Mwansa W , Sakala-Kazembe F , Sunkutu R , Zumla A
Published: May 2017

A significant association was observed among human immunodeficiency virus (HIV)-positive adult cases in Lusaka, Zambia compared with HIV-negative controls for chronic diarrhea (68% versus 22%; P < 0.05), weight loss (54% versus 30%; P < 0.05), lymphadenopathy (44% versus 15%; P < 0.05), and skin eruption (33% versus 7%; P < 0.05). Among the HIV-positive children, a higher proportion had clinical evidence of tuberculosis when compared with HIV-negative children (8% versus 1%; P < 0.05). The study demonstrated an association between weight loss in HIV-positive adults and children and chronic diarrhea (odds ratio [OR] = 12.7, 95% confidence interval [CI] = 6.4-25.5; P < 0.001), persistent cough (OR = 7.2, 95% CI = 2.9-14.5; P < 0.001), and an age of 31-45 years (OR = 3.8, 95% CI = 1.8-8.3; P < 0.01). The factors associated with mortality in HIV positive patients included chronic diarrhea (OR = 7.4, 95% CI = 1.6-34; P < 0.01), and lymphadenopathy (OR = 3.89, 95% CI = 1.2-12.2; P < 0.04).
Somatosensory discrimination deficits following pediatric cerebral malaria.
Authors: Dugbartey A T , Spellacy F J , Dugbartey M T
Published: May 2017

Pathologic studies of central nervous system damage in human falciparum malaria indicate primary localization in the cerebral white matter. We report a sensory-perceptual investigation of 20 Ghanaian children with a recent history of cerebral malaria who were age-, gender-, and education-matched with 20 healthy control subjects. Somatosensory examinations failed to show any evidence of hemianesthesia, pseudohemianesthesia, or extinction to double simultaneous tactile stimulation. While unilateral upper limb testing revealed intact unimanual tactile roughness discrimination, bimanual tactile discrimination, however, was significantly impaired in the cerebral malaria group. A strong negative correlation (r = -0.72) between coma duration and the bimanual tactile roughness discrimination test was also found. An inefficiency in the integrity of callosal fibers appear to account for our findings, although alternative subcortical mechanisms known to be involved in information transfer across the cerebral hemispheres may be compromised as well.
Ultrasonographic detection of living adult Wuchereria bancrofti using a 3.5-MHz transducer.
Authors: Dreyer G , Santos A , Noroes J , Amaral F , Addiss D
Published: May 2017

Adult Wuchereria bancrofti can be readily detected by ultrasound in the lymphatic vessels of the spermatic cord with a 7.5-MHz transducer, but most ultrasound machines in developing countries are equipped with 3.5-MHz transducers. To assess the potential for ultrasound as a tool for diagnosis and epidemiologic assessment in lymphatic filariasis, we compared the performance of 3.5-MHz and 7.5-MHz transducers in 61 men in Recife, Brazil. All men had three ultrasound examinations using a 3.5 MHz transducer and an examination with a 7.5-MHz probe. Using the 7.5-MHz transducer, adult W. bancrofti were detected in 41 men; 81 adult worm nests were detected. Sixty-four (79%) nests were detected with the 3.5-MHz probe, each on all three examinations. The 3.5-MHz probe correctly identified 35 (85.4%) of 41 men as infected; sensitivity increased with lymphatic vessel diameter. Ultrasonographic examination with a 3.5-MHz transducer is a sensitive method for detection of adult W. bancrofti in men and merits consideration as a tool for rapid epidemiologic assessment.
Pyomyositis associated with Bacteroides fragilis in a patient with multiple myeloma.
Authors: Matsuno O , Matsumoto T , Miyazaki E , Nakagawa H , Kumamoto T , Tsuda T
Published: May 2017

Pyomyositis is an infection of the skeletal muscle that is usually caused by Staphylococcus aureus. We report a 68-year-old Japanese woman who developed pyomyositis caused by Bacteroides fragilis following treatment for multiple myeloma. There are only two cases of pyomyositis associated with multiple myeloma in the literature. After receiving melphalan and prednisolone for five days, she developed multiple abscesses in the muscles of the right arm and thigh. Purulent exudate was aspirated from the abscess, and B. fragilis was identified. This is the first case of B. fragilis pyomyositis. Magnetic resonance imaging aided the diagnosis. Treatment consisted of surgical incision and drainage, with antibiotic administration. The immunosuppression caused by the myeloma and/or the chemotherapy presented a risk factor for the unusual infection observed in this patient.
Ultrasound-detected hepatic periportal thickening in patients with prolonged pyrexia.
Authors: Medhat A , Nafeh M , Swifee Y , Helmy A , Zaki S , Shehata M , Ibrahim S , Abdel-Kader D A , Strickland G T
Published: May 2017

Hepatic periportal thickening (HPT) detected by ultrasonography has been established as a reliable tool for measuring hepatic morbidity due to schistosomiasis. During ultrasonographic examination of patients with prolonged pyrexia, we frequently noticed minimal grades of HPT in patients without a history of schistosomiasis. This led to ultrasonographic studies of conditions other than schistosomiasis in which HPT may occur. Subjects included 460 patients with Schistosoma haematobium infection, 107 urban patients with prolonged pyrexia without previous exposure to schistosomiasis, and 288 healthy controls unexposed to schistosomiasis. Grade I HPT was more prevalent (P < 0.001) in patients with pyrexia (56.1%) than in those with S. haematobium (32.2%) and was more frequent (P < 0.001) in patients with S. haematobium than in controls (11.1%). Typhoid fever was the most common febrile illness causing HPT. Grade II lesions were rare in patients with pyrexia (2.8%) or schistosomiasis (0.9%). Grade III lesions were present in only one patient with S. haematobium. Mild grades of HPT can occur in infectious diseases other than schistosomiasis. Cellular infiltration in the portal tract from chronic infectious diseases can frequently give the ultrasonographic appearance of grade I HPT.
Development and laboratory evaluation of a polymerase chain reaction for monitoring Schistosoma mansoni infestation of water.
Authors: Hamburger J , Xu Y X , Ramzy R M , Jourdane J , Ruppel A
Published: May 2017

A sensitive and specific detection of cercariae of human schistosomes is required for better definition of risk of infection. In the present study, we have developed a polymerase chain reaction (PCR) assay for the detection of cercariae of Schistosoma mansoni in water. A simple DNA preparation was adapted for this purpose, and PCR primers were designed based on the 121-basepair highly repeated sequence we previously identified in the genome of S. mansoni. The PCR assay detected as little as 10(-6) ng of S. mansoni DNA, and the high sensitivity enabled the detection of a single cercaria. For trapping of cercariae we adapted a filtration apparatus previously used for separating schistosome eggs from turbid enzymatic digests of tissues. A single cercaria could be detected in repeated tests of water filtrates. Since the target DNA is tandemly arranged, a ladder pattern of the PCR products was demonstrated. A direct relationship was demonstrated between the number of ladder bands of the amplification products, and DNA concentration or number of cercariae. The feasibility of semiquantitation of schistosome larvae in natural water was thus suggested. The potential of the procedures described here for epidemiologic studies is discussed.
Gametocyte infectivity by direct mosquito feeds in an area of seasonal malaria transmission: implications for Bancoumana, Mali as a transmission-blocking vaccine site.
Authors: Toure Y T , Doumbo O , Toure A , Bagayoko M , Diallo M , Dolo A , Vernick K D , Keister D B , Muratova O , Kaslow D C
Published: May 2017

Infectivity of gametocytemic volunteers living in Bancoumana, a village 60 km from Bamako, Mali, was determined by direct feeds of laboratory-reared Anopheles gambiae s. l. Gametocytemic adolescents (10-18 years old) were as infectious to mosquitoes as younger volunteers and appear to be a more suitable population for testing transmission-blocking efficacy as compared with adults (> 18 years old). To begin to validate the membrane-feeding assay, sera collected from these same volunteers were subjected to a standard membrane-feeding assay. The data suggest that areas with intense but seasonal transmission might be feasible sites for testing transmission-blocking vaccines because of the high gametocytemic rates, high mosquito infectivity rates, and lack of pre-existing humoral-mediated transmission-blocking activity. The differences observed between field-based direct mosquito feeds and laboratory-based membrane feeding assays suggests that caution be used in interpreting Phase I study results in which laboratory-based membrane-feeding assays are used as a surrogate for vaccine efficacy.
Heart autonomic innervation during the acute phase of experimental American trypanosomiasis in the dog.
Authors: Machado C R , Caliari M V , de Lana M , Tafuri W L
Published: May 2017

Heart autonomic innervation was studied in dogs during the acute phase of the experimental infection with the Berenice-78 strain of Trypanosoma cruzi. A glyoxylic acid-induced fluorescence method for catecholamines and a thiocholine method for demonstrating acetylcholinesterase activity showed the sympathetic and the parasympathetic nerve fibers, respectively. At day 34 of infection, moderate-to-intense rarefaction of both cholinergic and noradrenergic nerve fibers occurred in the atria of all animals coincident with moderate to intense myocarditis. In the ventricles, sympathetic denervation was clearly present only when the inflammatory processes were moderate to intense. Preliminary results on the chronic phase indicate that normal autonomic innervation coexists with an incipient chronic fibrosing myocarditis.
Nitric oxides in plasma, urine, and cerebrospinal fluid in patients with severe falciparum malaria.
Authors: Dondorp A M , Planche T , de Bel E E , Angus B J , Chotivanich K T , Silamut K , Romijn J A , Ruangveerayuth R , Hoek F J , Kager P A , Vreeken J , White N J
Published: May 2017

It has been suggested that nitric oxide (NO) plays an important role in the pathogenesis of severe falciparum malaria. Since NO has a very short half-life, nitrate and nitrite (NOx) levels, stable metabolites of NO, are used as measures of NO production. We measured plasma NOx levels in 24 adults with severe falciparum malaria on the Thai-Burmese border. After correction for renal function, there was no correlation between plasma NOx levels, or the total amount of NOx excreted in the urine, and disease severity. Plasma NOx levels decreased after the first 48 hr in all patients (P = 0.007), suggesting decreased NO production. The NOx levels in cerebrospinal fluid (CSF) correlated well with plasma NOx levels, but these did not show a correlation with coma depth, and were not significantly different from those in a healthy control group. These findings do not support the hypothesis that excessive NO production contributes to the pathogenesis of severe falciparum malaria. However, local changes in NO production, e.g., in the central nervous system, might not be reflected in the total NOx production or NOx levels in the CSF.
Paralytic ileus due to strongyloidiasis: case report and review of the literature.
Authors: Nonaka D , Takaki K , Tanaka M , Umeno M , Takeda T , Yoshida M , Haraguch Y , Okada K , Sawae Y
Published: May 2017

We report a rare case of a patient with ileus due to Strongyloides infection that occurred four times within a six-month period. The ileus was improved by treatment with ivermectin and there has not been a recurrence of the symptoms within the last two years.
Role of the spleen on the pathogenesis of schistosomal periportal (pipestem) fibrosis of the liver: an experimental approach.
Authors: Andrade Z A , Silva L M , de Souza M M , Sadigursky M , Barbosa A , de Oliveira I R
Published: May 2017

Splenectomized and sham-operated mice with chronic Schistosoma mansoni infection were compared for the development of periportal fibrosis (pipestem fibrosis). Although this lesion appeared less frequently in splenectomized mice, it also developed in the absence of the spleen. The time of splenectomy, spleen weight, presence of anti-idiotypic antibodies, the number of eggs in the liver, and the type and size of periovular granulomas in the liver as evaluated by computerized morphometry did not show statistically significant differences between the two groups. It is concluded that the role of the spleen in the development of pipestem fibrosis seems ancillary and that multifactorial influences, including worm burden, hepatic vascular adjustment, and factors associated with the biology of extracellular matrix of the liver, probably play a more significant role.
Hepatitis C virus genotypes and hepatitis G virus in hemodialysis patients from Syria: identification of two novel hepatitis C virus subtypes.
Authors: Abdulkarim A S , Zein N N , Germer J J , Kolbert C P , Kabbani L , Krajnik K L , Hola A , Agha M N , Tourogman M , Persing D H
Published: May 2017

High prevalence of hepatitis C (HCV) and hepatitis G (HGV) viruses has been reported among hemodialysis patients with substantial heterogeneity of HCV genotypes throughout the world. We studied HCV prevalence, clinical significance, genotype distribution, and HGV coinfection in hemodialysis patients from Syria. Ninety (75%) of 120 screened patients were HCV antibody positive. Forty-nine (87.5%) of 56 HCV antibody-positive patients had HCV RNA detected by the polymerase chain reaction. The HCV genotyping was possible in 37 of 49 patients (76%). The HCV genotype distribution was genotype 1a, seven (19%); genotype 1b, 10 (27%); genotype 4a, 11 (30%); unmatched sequences, nine (24%). Phylogenetic analysis of unmatched sequences indicated that they represent two distinct and novel subtypes of HCV genotype 4. Hepatitis G virus RNA was detected in 29 (59%) of the HCV RNA-positive patients. No differences were identified between patients infected with HCV alone and those coinfected with HGV. These data demonstrate that HCV infection is common in this population with a genotype distribution predominantly made up of types 1 and 4. Coinfection with HGV had no effect on the outcome of HCV infection.
Lake Vera revisited: parity and survival rates of Anopheles punctipennis at the site of a malaria outbreak in the Sierra Nevada foothills of California.
Authors: Jensen T , Dritz D A , Fritz G N , Washino R K , Reeves W C
Published: May 2017

Parity and survival rates of Anopheles punctipennis were studied at the site of a 1952 outbreak of malaria in the Sierra Nevada foothills of California with the purpose of estimating blood feeding frequency and survivorship of such populations. Anopheles punctipennis was the dominant species in landing collections conducted for 20 consecutive nights in August and September 1990. The mean parity rate of An. punctipennis was 0.82. The gonotrophic cycle was estimated to last three days based on time series analysis of the number of nulliparous and parous mosquitoes collected each day. Survivorship was estimated to be 0.79 per gonotrophic cycle and 0.92 per day. Ovarian dilatation data indicated that some females had completed eight gonotrophic cycles prior to being collected and 45% of the females completed two or more cycles. The high prevalence of multiparous individuals, high parity rate, long survivorship and a short three-day gonotrophic cycle estimate indicates that this population is long lived and has a capacity to be an efficient vector of malaria.
Cryptosporidiosis in Indonesia: a hospital-based study and a community-based survey.
Authors: Katsumata T , Hosea D , Wasito E B , Kohno S , Hara K , Soeparto P , Ranuh I G
Published: May 2017

Hospital-based and community-based studies were conducted to understand the prevalence and mode of transmission of Cryptosporidium parvum infection in Surabaya, Indonesia. In both studies people with and without diarrhea were examined for oocysts. A community-based survey included questionnaires to a community and stool examination of cats. Questionnaires covered demographic information, health status, and hygienic indicators. In the hospital, C. parvum oocysts were found in 26 (2.8%) of 917 patients with diarrhea and 15 (1.4%) of 1,043 control patients. The most susceptible age was less than two years old. The prevalence was higher during the rainy season. A community-based study again showed that C. parvum oocysts were frequently detected in diarrhea samples (8.2%), exclusively during rainy season. Thirteen (2.4%) of 532 cats passed C. parvum oocysts. A multiple logistic regression model indicated that contact with cats, rain, flood, and crowded living conditions are significant risk factors for Cryptosporidium infection.
Group B streptococcal colonization in a developing country: its association with sexually transmitted disease and socioeconomic factors.
Authors: Collins T S , Calderon M , Gilman R H , Vivar A , Charache P
Published: May 2017

Group B Streptococcus (GBS) is an important infectious organism in pregnant women and their neonates. Although excellent data are available from the developing world, little epidemiologic information is available from Latin America. To evaluate the prevalence of GBS colonization in a developing country, a prospective study was performed in Lima, Peru. We found a relatively low prevalence of GBS colonization of 6.0% in parturient women and 10.6% in nonpregnant women. No association of GBS colonization was made with previously identified risk factors such as age, parity, or birth control practices. We did find a positive association between GBS colonization and chlamydial carriage (P < 0.05). We also report an even distribution of GBS serotypes: Ia/c = 35%, IIc = 18%, III = 29%, and V = 18%. Our study provides evidence for a low prevalence of GBS maternal carriage in this urban Latin American population.
The elimination of hepatitis B virus infection: changing seroepidemiology of hepatitis A and B virus infection in Okinawa, Japan over a 26-year period.
Authors: Furusyo N , Hayashi J , Sawayama Y , Kawakami Y , Kishihara Y , Kashiwagi S
Published: May 2017

Serial changes in hepatitis A virus (HAV) and B virus (HBV) markers were determined from 1970 to 1996 in healthy Japanese residents of a rural area of Okinawa, Japan. All 190 serum samples taken in 1970, 791 in 1980, 708 in 1988, and 523 in 1996 from residents 0 to more than 60 years of age were tested for antibody to HAV (anti-HAV), antibody to hepatitis B core antigen (anti-HBc), and hepatitis B surface antigen (HBsAg). The age-adjusted prevalences of anti-HAV and anti-HBc decreased significantly from 83.9% and 74.9%, respectively, in 1970 to 39.7% and 36.6%, respectively, in 1996. In residents < or = 29 years of age, the prevalences of anti-HAV and anti-HBc decreased significantly from 65.3% and 83.8%, respectively, in 1970 to 0.7% and 8.2%, respectively, in 1996. The age-adjusted HBsAg prevalence decreased significantly from 8.2% in 1980 to 4.1% in 1988. These results indicate that exposure to HAV and HBV infections among Okinawa residents less than 29 years of age is decreasing, probably because of improvements in socioeconomic conditions since 1970. Infection with HBV may be eliminated there in the near future.
Black Creek Canal Virus infection in Sigmodon hispidus in southern Florida.
Authors: Glass G E , Livingstone W , Mills J N , Hlady W G , Fine J B , Biggler W , Coke T , Frazier D , Atherley S , Rollin P E , Ksiazek T G , Peters C J , Childs J E
Published: May 2017

A total of 1,500 small mammals were collected and tested for antibodies cross-reactive to Sin Nombre virus (Hantavirus: Bunyaviridae) at 89 sites in a 1,600 km2 study area of southern Florida. More than 95% of the 123 seropositive animals were cotton rats (Sigmodon hispidus), suggesting infection by Black Creek Canal Virus, although seroreactive Rattus rattus (5 of 294) and Peromyscus gossypinus (1 of 39) also were captured. Crude seroprevalence in S. hispidus was 11%. Seroprevalence increased with body size and was more common in male (18%; n=451) than in female (6%; n=593) cotton rats. Infection within S. hispidus populations was widespread throughout the study area. Prevalence ranged from 0% to 60% at sites where more than five cotton rats were sampled but was not only a function of sample size. Sites with seropositive cotton rats were geographically clustered compared with sites with no seropositive cotton rats. Clustering was not due to the spatial distribution of sites with few animals, season of collection, or sex bias of animals captured at these sites. However, sites with no seropositive animals had an excess of animals in the intermediate size class (60-99 g) and a deficit of the largest and smallest animals. These data suggest that population structure within the habitat mosaic may play a significant role in the spatial distribution of hantavirus infection in local populations of reservoir species.
Evolution of Schistosoma haematobium-related pathology over 24 months after treatment with praziquantel among school children in southeastern Tanzania.
Authors: Hatz C F , Vennervald B J , Nkulila T , Vounatsou P , Kombe Y , Mayombana C , Mshinda H , Tanner M
Published: May 2017

Little is known about the dynamics of pathology due to schistosomiasis following treatment. Public health authorities in endemic areas require such information to decide on the timing of treatment and re-treatment schedules. A study to assess the rate of clearance and reappearance of pathologic lesions due to Schistosoma haematobium using ultrasound has now been carried out in two schools in southeastern Tanzania, an area of moderate-to-high transmission. Baseline data collection found urinary tract pathology in 67% of 533 children. Lesions of the bladder were significantly associated with egg positivity and microhematuria. The attributable fraction estimate of major bladder lesions due to S. haematobium was 75%. In a cohort study, 224 infected children were examined by ultrasound and then treated with a standard dose of 40 mg of praziquantel/kg of body weight. They were re-examined at two, four, six, 12, 18, and 24 months after treatment. Before treatment, 76% had pathologic lesions of the urinary tract. The proportion showing lesions decreased sharply during the first months after treatment to 11% at six months. At 24 months, lesions were detected in 57%, and 11% had developed new severe pathology. In 18 cases, pathology was present throughout, and 34 did not show any pathology throughout the study. This study provides the first detailed report on the evolution of urinary tract pathology due to S. haematobium infections at the community level. The results will help in making decisions on treatment and re-treatment schedules and more generally will provide a basis for designing control strategies in areas of moderate-to-high transmission.
Prospective study of the incidence of diarrheal disease and Helicobacter pylori infection among children in an orphanage in Thailand.
Authors: Isenbarger D W , Bodhidatta L , Hoge C W , Nirdnoy W , Pitarangsi C , Umpawasiri U , Echeverria P
Published: May 2017

To evaluate the hypothesis that gastric infection with Helicobacter pylori increases risk for diarrheal disease in children, we conducted a yearlong prospective study among 160 orphanage children < 5 years of age in Nonthaburi, Thailand. Serum samples collected at six-month intervals were examined by ELISA for antibodies to H. pylori, and children were followed daily for the development of diarrhea. Seven percent of children were seropositive on enrollment, 59% were seronegative, and 34% were indeterminate. Among the seronegative children, seroconversion occurred at a rate of 7% per six months. Forty-six percent of children developed 214 total episodes of diarrhea. By age group, children < 18 months, 18-24 months and > 24 months of age experienced 2.6, 1.1, and 0.2 mean diarrhea episodes per six months. The incidence of diarrhea was not significantly different between children by H. pylori serostatus. We conclude that H. pylori infection was not associated with an increased risk of diarrheal disease.
A pharmacokinetic and pharmacodynamic study of artesunate for vivax malaria.
Authors: Batty K T , Le A T , Ilett K F , Nguyen P T , Powell S M , Nguyen C H , Truong X M , Vuong V C , Huynh V T , Tran Q B , Nguyen V M , Davis T M
Published: May 2017

To investigate the pharmacokinetic and pharmacodynamic properties of artesunate (ARTS) and its active metabolite dihydroartemisinin (DHA) in Plasmodium vivax infections, 12 male Vietnamese adults with slide-positive vivax malaria received either intravenous ARTS (120 mg; group 1) or oral ARTS (100 mg; group 2) with the alternative preparation given 8 hr later in a randomized, open, cross-over study. Following intravenous injection, ARTS had a peak plasma drug concentration (Cmax) of 35.6 microM (13.7 mg/L), an elimination half-life (t1/2) of 2.2 min, a clearance (CL) of 3.0 L/hr/kg, and a volume of distribution (V) of 0.16 L/kg. Dihydroartemisinin had a Cmax of 7.7 microM (2.2 mg/L), a tmax of 8 min, a t1/2 of 37 min, an apparent CL of 1.1 L/hr/kg, and an apparent V of 0.9 L/kg. Following oral ARTS, the mean relative bioavailability of DHA was 85%, the Cmax was 3.0 microM (0.85 mg/L), the tmax was 75 min, and t1/2 was 40 min. The mean time to 50% reduction in the parasite count (PCT50) and median fever clearance time were 3 hr and 16 hr, respectively. Following intravenous ARTS (group 1), the PCT50 for total parasites, rings, trophozoites, and gametocytes was 3.3 hr, 3.2 hr, 4.0 hr, and 3.6 hr, respectively. This study confirms that ARTS is effective against P. vivax, with rapid clearance of sexual and asexual forms of the parasite. Artesunate is a suitable initial treatment for vivax malaria, or when the plasmodial species cannot be reliably identified.
Treatment of onchocerciasis with ivermectin (Province of Bururi, Burundi): parasitologic and clinical evaluation of different periodicities of treatment.
Authors: Vyungimana F , Newell E
Published: May 2017

To find out whether biannual treatments of onchocerciasis with ivermectin were necessary or whether annual treatments could suffice, parasitologic and clinical results in Burundi were compared at 12 months after a single treatment and after two treatments with an interval of six months. Adverse reactions were also compared at 12 months, after a second or third treatment, respectively. The biannual treatment resulted in a greater reduction of parasitologic parameters, had a longer-lasting effect on itching, and produced less side effects (especially itching, rash, and swellings) at 12 months than an annual treatment. Skin lesions were not significantly modified by any of the treatment schemes at 12 months. Notwithstanding this slight advantage of biannual treatment, operational constraints forced us to choose an annual distribution of ivermectin. With minimal resources, a distribution scheme was organized that was adapted to the different levels of endemicity of onchocerciasis. The results of this study may be of interest to policy makers and public health officials in areas where logistical and resource issues severely restrict the scope of treatment programs. In view of the planned activities of the African Programme of Onchocerciasis Control, the achievements in Burundi indicate that even with limited resources, an appropriate annual distribution scheme can give meaningful results. In spite of the persistence of skin lesions, their severity decreased and most patients considered that their condition had improved even after just one year.
Response to conjugate Haemophilus influenzae B vaccine among infants in Niamey, Niger.
Authors: Campagne G , Garba A , Schuchat A , Boulanger D , Plikaytis B D , Ousseini M , Chippaux J P
Published: May 2017

Despite near elimination of Haemophilus influenzae b (Hib) meningitis from several industrialized countries following introduction of conjugate Hib vaccines into infant immunization schedules, Hib remains a major cause of meningitis and pneumonia in resource-poor countries. In Niger, Hib causes nearly 200 cases of meningitis per 100,000 children < one year of age, and > 40% of cases are fatal. We evaluated the immunogenicity of Hib polysaccharide-tetanus toxoid conjugate vaccine (PRP-T) administered in the same syringe as diphtheria-tetanus-pertussis (DTP) vaccine among infants in Niger. Infants were randomized into group 1 (PRP-T at six, 10, and 14 weeks), group 2 (PRP-T at 10 and 14 weeks), or a control group (meningococcal A/C polysaccharide vaccine). By 14 weeks of age, all subjects in groups land 2 had > or = 0.15 microg/ml of anti-PRP antibody, and 82% versus 76% had > or = 1.0 microg/ml of antibody (P=not significant). By nine months of age the proportion of infants with > or = 0.15 and > or = 1.0 microg/ml was group I=97% and 76%; group 2=93% and 67%; controls=10% and 2.6%. Four weeks after the first, second, and third doses of PRP-T, infants in group 1 showed geometric mean titers (GMTs) of 0.19, 3.97, and 6.09 microg/ml while infants in group 2 had GMTs of 2.40 and 4.41 microg/ml four weeks after the delayed first and second doses. Both PRP-T groups had significantly higher GMTs at 18 weeks and nine months of age than infants in the control group. The Hib PRP-T vaccine was immunogenic in infants in Niger. The strong response after PRP-T was initiated one month after the first DTP vaccination may reflect carrier priming. Two dose schedules of PRP-T should be given serious consideration, particularly if their reduced cost permits vaccine introduction that would be otherwise unaffordable.
Involvement of macrophage scavenger receptors in protection against murine malaria.
Authors: Nogami S , Watanabe J , Nakagaki K , Nakata K , Suzuki H , Fujisawa M , Kodama T , Kojima S
Published: May 2017

Macrophage scavenger receptor A (MSR-A) deficient mice MSR-A(-/-) were infected by the intraperitoneal injection of the Plasmodium berghei NK65 strain in the erythrocytic stage. The MSR-A(-/-) mice died significantly earlier than the control mice (P=0.060). In the surviving mice, two peaks of parasitemia were observed: the first 5-7 days and the second at 2-3 weeks after infection. Death of all MSR-A(-/-) mice occurred at either peak of parasitemia, suggesting that MSR-A protects mice from severe infection. This model may be useful for the study of molecular mechanisms of macrophage functions in malaria infection.
Correlation of increased expression of intercellular adhesion molecule-1, but not high levels of tumor necrosis factor-alpha, with lethality of Plasmodium yoelii 17XL, a rodent model of cerebral malaria.
Authors: Shear H L , Marino M W , Wanidworanun C , Berman J W , Nagel R L
Published: May 2017

Previous studies demonstrated that Plasmodium yoelii 17XL, a lethal strain of rodent malaria, causes a syndrome in SW mice that resembles human cerebral malaria. The mouse brain pathology is characterized by cytoadherence of parasitized erythrocytes. Here, the possible mechanisms mediating cerebral malaria in this model were studied and the results were compared with a nonlethal strain of this parasite, P. yoelii 17XNL (nonlethal), which does not cause cerebral malaria. Immunostaining for intercellular adhesion molecule-1 (ICAM-1) revealed an increase in expression of this protein in the small venules and capillaries of the brains of infected mice that increased with time after infection. Staining was more pronounced during the lethal infection than the nonlethal infection. Some staining with monoclonal antibody to vascular cell adhesion molecule-1 was also observed, but it was quantitatively less than ICAM-1 staining and was limited to larger venules. During the lethal infection, levels of tumor necrosis factor-alpha (TNF-alpha) increased rapidly, peaking on day 4. In contrast, mice infected with nonlethal P. yoelii had a slower serum TNF-alpha response that peaked on day 10, prior to the maximum parasitemia. In addition, mice with a targeted disruption of the TNF-alpha gene (TNF-alpha-/- mice) were infected with the lethal and nonlethal strains of P. yoelii 17X. The TNF-alpha-/- mice infected with the nonlethal parasite had significantly higher levels of parasitemia than controls, whereas TNF-alpha-/- mice infected with the lethal strain had slightly higher levels of infected erythrocytes but were equally susceptible to death from this infection. Thus, TNF-alpha does not appear to be essential in mediating death. These results demonstrate that P. yoelii 17XL infection has features in common with human cerebral malaria and suggest that this model may be useful in testing strategies to alleviate this syndrome.
A polymerase chain reaction assay for detecting snails infected with bilharzia parasites (Schistosoma mansoni) from very early prepatency.
Authors: Hamburger J , He-Na  , Xin X Y , Ramzy R M , Jourdane J , Ruppel A
Published: May 2017

In the present study, we adapted a polymerase chain reaction (PCR) assay, previously shown by us to be very sensitive for detecting cercariae in water, for the sensitive detection of Schistosoma mansoni DNA in infected snails from early prepatency. Polymerase chain reaction primers were designed based on the 121-basepair highly repeated sequence we previously identified in the genome of S. mansoni. The DNA was prepared from the snails by a simple alkaline extraction procedure, and the PCR assay enabled a clear differentiation between infected and normal snails. Infected snails were detected as early as one day after penetration of a single miracidium. The high sensitivity of the test enabled identification of a single infected snail even when its DNA was pooled with material from up to 99 uninfected snails, thus demonstrating the possibility of mass diagnosis in pools of snails. The assay has the potential for large-scale determination of prepatent infection prevalence in snails, thus offering new possibilities for the evaluation of schistosomiasis transmission and for schistosomiasis control, as discussed.