Microbiological diagnosis of polymicrobial periprosthetic joint infection revealed superiority of investigated tissue samples compared to sonicate fluid generated from the implant surface.

Objectives: In the microbiological diagnosis of periprosthetic joint infection (PJI), there is much discussion about the methodology of obtaining proper specimens, the processing technique, and suitable culture media. This retrospective study was conducted to analyse the accuracy of our culture techniques.

Methods: Tissue samples and components from 258 patients after revision arthroplasty of the hip, knee, and shoulder were investigated, and the results of tissue cultures (TC) were compared to those of sonicate fluid cultures (SFC).

Evaluation of onchocerciasis control in the Upper Denkyira East municipal in the forest area of Ghana: Responses of participants and distributors to the CDTI programme.

The African Programme for Onchocerciasis Control (APOC), which focused on annual mass treatment with ivermectin, was launched in 1995 and was replaced by the Expanded Special Project for Neglected Tropical Diseases (ESPEN) by the end of 2015. In Ghana, the Community Directed Treatment with Ivermectin (CDTI) was introduced in 1999. After a decade, biannual reinforcement was introduced during which the Ghana Health Service (GHS) recorded coverage rates through routine data collection.

Similar virus spectra and seasonality in paediatric patients with acute respiratory disease, Ghana and Germany.

Epidemiological differences between tropical and temperate regions regarding viruses causing acute respiratory infection are poorly understood. This is in part because methodological differences limit the comparability of data from these two regions. Using identical molecular detection methods, we tested 1174 Ghanaian and 539 German children with acute respiratory infections sampled over 12 months for the 15 most common respiratory viruses by PCR.

Prevalence of malaria parasitaemia in school children from two districts of Ghana earmarked for indoor residual spraying: a cross-sectional study.

Background: Indoor residual spraying (IRS) is considered a valuable transmission control measure against malaria but exact efficacy data are not available for many epidemiological settings. This study was conducted to determine indicators for malaria epidemiology and transmission among school children as baseline assessment before IRS implementation in Ghana.

Methods: A cross-sectional study was conducted in Adansi South District of the Ashanti Region and Wa West District of the Upper West Region of Ghana.

Palp ratio as a field identification tool for two members of the Anopheles gambiae complex in Ghana (A. melas and A. gambiae).

Background: The Anopheles gambiae Giles complex is the most widely studied and the most important insect vector group. We explored the use of the palp ratio method as a field tool to identify A. melas and A.

Assessments of the transmission of Onchocerca volvulus by Simulium sanctipauli in the Upper Denkyira District, Ghana, and the intermittent disappearance of the vector.

Following studies on the transmission of Onchocerca volvulus (Leuckart) by Simulium sanctipauli Vajime & Dunbar (Diptera, Simuliidae) in Upper Denkyira District in Ghana in 2001 and 2002 (Kutin et al., Med Vet Ent 18:167-173, 2004), further assessments were carried out in 2006 and 2013/2014 to determine whether transmission parameters had changed since community-directed ivermectin treatment (CDTI) began in 1999. There were no marked changes of the transmission intensities in 2006.

Malaria transmission intensity and dynamics of clinical malaria incidence in a mountainous forest region of Ghana.

Background: Malaria transmission is heterogeneous. Villages close to each other may have very different transmission characteristics. The presence and abundance of malaria vectors is governed by local ecology and microclimate.

Use of Bacillus thuringiensis var israelensis as a viable option in an Integrated Malaria Vector Control Programme in the Kumasi Metropolis, Ghana.

Background: Integrated Vector Control (IVC) remains the approach for managing the malaria-causing vector. The study investigated the contribution of Bacillus thuringiensis israelensis (Bti) in the control of malaria by targeting the larvae and also mapped and documented major breeding sites in the Kumasi metropolis, Ghana.

Methods: Using a hand held GPS receiver unit, major breeding sites within the metropolis were mapped out during the larval survey.

The ecology of mosquitoes in an irrigated vegetable farm in Kumasi, Ghana: abundance, productivity and survivorship.

Background: Irrigated vegetable farms within the city of Kumasi, Ghana, create hotspots for the breeding of malaria vectors, which could lead to high transmission of malaria. This study investigated the abundance and productivity of mosquitoes in an irrigated vegetable farm in Kumasi, Ghana.

Methods: Adult mosquito productivity was estimated five days in a week in different irrigated scheme types (dug-out wells, furrows and footprints) for 12 weeks using emergence traps.

The effect of deltamethrin-treated net fencing around cattle enclosures on outdoor-biting mosquitoes in Kumasi, Ghana.

Classic vector control strategies target mosquitoes indoors as the main transmitters of malaria are indoor-biting and -resting mosquitoes. However, the intensive use of insecticide-treated bed-nets (ITNs) and indoor residual spraying have put selective pressure on mosquitoes to adapt in order to obtain human blood meals. Thus, early-evening and outdoor vector activity is becoming an increasing concern.

Bats host major mammalian paramyxoviruses.

The large virus family Paramyxoviridae includes some of the most significant human and livestock viruses, such as measles-, distemper-, mumps-, parainfluenza-, Newcastle disease-, respiratory syncytial virus and metapneumoviruses. Here we identify an estimated 66 new paramyxoviruses in a worldwide sample of 119 bat and rodent species (9,278 individuals). Major discoveries include evidence of an origin of Hendra- and Nipah virus in Africa, identification of a bat virus conspecific with the human mumps virus, detection of close relatives of respiratory syncytial virus, mouse pneumonia- and canine distemper virus in bats, as well as direct evidence of Sendai virus in rodents.

Soft repulsive mixtures under gravity: brazil-nut effect, depletion bubbles, boundary layering, nonequilibrium shaking.

A binary mixture of particles interacting via long-ranged repulsive forces is studied in gravity by computer simulation and theory. The more repulsive A-particles create a depletion zone of less repulsive B-particles around them reminiscent to a bubble. Applying Archimedes' principle effectively to this bubble, an A-particle can be lifted in a fluid background of B-particles.

Chemotactic predator-prey dynamics.

A discrete chemotactic predator-prey model is proposed in which the prey secrets a diffusing chemical which is sensed by the predator and vice versa. Two dynamical states corresponding to catching and escaping are identified and it is shown that steady hunting is unstable. For the escape process, the predator-prey distance is diffusive for short times but exhibits a transient subdiffusive behavior which scales as a power law t¹/³ with time t and ultimately crosses over to diffusion again.

Malaria transmission in two rural communities in the forest zone of Ghana.

Malaria transmission was assessed in two rural communities, Kona and Afamanaso in Sekyere South district, Ashanti Region, in the forest zone of Ghana to provide baseline data for ongoing clinical studies and the evaluation of the effect of interventions. Altogether, 3,479 Anopheles gambiae and 1,157 Anopheles funestus were caught by human landing catches. Sporozoite rates determined by either microscopy of salivary glands or enzyme-linked immunosorbent assay (ELISA) for Plasmodium falciparum in the two villages were 6.

Blood-feeding behavior of Anopheles gambiae and Anopheles melas in Ghana, western Africa.

Anopheles gambiae is the predominant malaria vector species in Ghana, western Africa, with a strong local presence of Anopheles melas Theobald along the southern coast. We studied the biting behavior of these two species of the Anopheles gambiae complex inland and at the coast in Ghana, with special attention to the local peoples' preference for outdoor sleeping. We collected mosquitoes at two sites in 2007, representing the moist semideciduous forest zone and the strand and mangrove zone, and the sampling was repeated in the dry and rainy seasons.

Distant relatives of severe acute respiratory syndrome coronavirus and close relatives of human coronavirus 229E in bats, Ghana.

We tested 12 bat species in Ghana for coronavirus (CoV) RNA. The virus prevalence in insectivorous bats (n = 123) was 9.76%.

Henipavirus RNA in African bats.

Background: Henipaviruses (Hendra and Nipah virus) are highly pathogenic members of the family Paramyxoviridae. Fruit-eating bats of the Pteropus genus have been suggested as their natural reservoir. Human Henipavirus infections have been reported in a region extending from Australia via Malaysia into Bangladesh, compatible with the geographic range of Pteropus.

A stepwise approach to the laboratory diagnosis of Buruli ulcer disease.

Objective: In view of technical and financial limitations in areas of endemicity, the current practice and recommendations for the laboratory diagnosis of Buruli ulcer disease (BUD) may have to be reconsidered. We reviewed diagnostic results in order to explore options for a modified, more practicable, cost-effective and timely approach to the laboratory diagnosis of BUD.

Methods: Diagnostic specimens from 161 clinically diagnosed BUD patients from four different treatment centres in Ghana were subjected to laboratory analysis.

Dry-reagent-based PCR as a novel tool for laboratory confirmation of clinically diagnosed Mycobacterium ulcerans-associated disease in areas in the tropics where M. ulcerans is endemic.

After tuberculosis and leprosy, Buruli ulcer (BU), caused by Mycobacterium ulcerans, is the third most common mycobacterial disease in immunocompetent humans. The disease occurs in tropical countries, with foci in West Africa, Central Africa, and the western Pacific. BU is defined as an infectious disease involving the skin and the subcutaneous adipose tissue characterized by a painless nodule, papule, plaque, or edema, evolving into a painless ulcer with undermined edges and often leading to invalidating sequelae.

Efficiency of Simulium sanctipauli as a vector of Onchocerca volvulus in the forest zone of Ghana.

The role of Simulium sanctipauli Vajime & Dunbar (Diptera: Simuliidae) as a vector of Onchocerca volvulus (Leuckart) (Spirurida: Onchocercidae) in the forest zone of central Ghana was studied in the Upper Denkyira district, where onchocerciasis is hyperendemic. Simulium sanctipauli was found to be a highly efficient vector, with a mean of 377 infective (L3) larvae in the heads of 1000 parous and 122 in the heads of 1000 biting flies. The overall infection rate of 44% of the parous flies with L1, L2 and L3 stages of O.

Does irrigated urban agriculture influence the transmission of malaria in the city of Kumasi, Ghana?

To verify the possible impact of irrigated urban agriculture on malaria transmission in cities, we studied entomological parameters, self-reported malaria episodes, and household-level data in the city of Kumasi, Ghana. A comparison was made between city locations without irrigated agriculture, city locations with irrigated urban vegetable production, and peri-urban (PU) locations with rain-fed agriculture. In the rainy as well as dry seasons, larvae of Anopheles spp.

Doxycycline as a novel strategy against bancroftian filariasis-depletion of Wolbachia endosymbionts from Wuchereria bancrofti and stop of microfilaria production.

Chemotherapy of onchocerciasis by doxycycline, which targets symbiotic Wolbachia endobacteria, has been shown to result in a long-term sterility of adult female worms and corresponding absence of microfilariae. It represents an additional chemotherapeutic approach. The aim of this study was to determine whether a similar regimen would also show efficacy against Wuchereria bancrofti.

Rapid elimination of GB virus C (hepatitis G virus) in the mosquito Aedes aegypti.

The transmissibility of the GB virus C (hepatitis G virus; HGV), a member of the Flaviviridae, by a typical flavivirus vector was investigated. Female mosquitoes of the species Aedes aegypti were fed with HGV-infected human blood and assayed 1, 24, 48, 72 and 96 h after the blood meal for viral RNA, human glyceraldehyde-3-phosphate dehydrogenase mRNA, human beta-actin DNA and A. aegypti actin mRNA by total nucleic acid extraction, reverse transcription and PCR.

Similar blackfly attraction by onchocerciasis patients and individuals putatively immune to Onchocerca volvulus.

In areas endemic for onchocerciasis, a small number of individuals show no detectable infection with Onchocerca volvulus despite an apparently similar exposure to the transmitting blackflies. Such individuals have been termed putatively immune. Since several studies have indicated marked host differences in attractiveness for blood-seeking insects, putative immunity in O.