Estimating the Disease Burden of Pandemic (H1N1) 2009 Virus Infection in Hunter New England,Northern New South Wales,Australia, 2009

Introduction

On May 26, 2009, the first confirmed case of Pandemic (H1N1) 2009 virus (pH1N1) infection in Hunter New England (HNE), New South Wales (NSW), Australia (population 866,000) was identified. We used local surveillance data to estimate pH1N1-associated disease burden during the first wave of pH1N1 circulation in HNE.

Methods

Surveillance was established during June 1-August 30, 2009, for: 1) laboratory detection of pH1N1 at HNE and NSW laboratories, 2) pH1N1 community influenza-like illness (ILI) using an internet survey of HNE residents, and 3) pH1N1-associated hospitalizations and deaths using respiratory illness International Classification of Diseases 10 codes at 35 HNE hospitals and mandatory reporting of confirmed pH1N1-associated hospitalizations and deaths to the public health service. The proportion of pH1N1 positive specimens was applied to estimates of ILI, hospitalizations, and deaths to estimate disease burden.

Results

Of 34,177 specimens tested at NSW laboratories, 4,094 (12%) were pH1N1 positive. Of 1,881 specimens from patients evaluated in emergency departments and/or hospitalized, 524 (26%) were pH1N1 positive. The estimated number of persons with pH1N1-associated ILI in the HNE region was 53,383 (range 37,828–70,597) suggesting a 6.2% attack rate (range 4.4–8.2%). An estimated 509 pH1N1-associated hospitalizations (range 388–630) occurred (reported: 184), and up to 10 pH1N1-associated deaths (range 8–13) occurred (reported: 5). The estimated case hospitalization ratio was 1% and case fatality ratio was 0.02%.

Discussion

The first wave of pH1N1 activity in HNE resulted in symptomatic infection in a small proportion of the population, and the number of HNE pH1N1-associated hospitalizations and deaths is likely higher than officially reported.     

Efficacy of three insect repellents against the malaria vector Anopheles arabiensis

Three commercial repellents marketed in South Africa: Bio-Skincare (BSC, oils of coconut, jojoba, rapeseed and vitamin E), Mosiguard towelletes with 0.574 g quwenling (p-menthane-3,8-diol, PMD) and the standard deet (15% diethyl-3-methylbenzamide, Tabard lotion), were compared against a laboratory colony of the mosquito Anopheles arabiensis Patton (Diptera: Culicidae), the predominant malaria vector in South Africa. Human forearms were treated with 1.2 g BSC, 0.8 g PMD towelette or 0.5 g deet and exposed to 200 hungry An. arabiensis females for 1 min, at intervals of 1-6 h post-treatment. Tests were conducted by three adult male volunteers (aged 30-45 years, crossover controlled test design for 3 consecutive days), using their left arm for treatment and right arm for untreated control. Biting rates averaged 39-52 bites/min on untreated arms. All three repellents provided complete protection against An. arabiensis for up to 3-4 h post-application; deet and PMD gave 90-100% protection up to 5-6h, but BSC declined to only 52% protection 6h post-treatment. These results are interpreted to show that all three repellent products give satisfactory levels of personal protection against An. arabiensis for 4-5 h, justifying further evaluation in the field.     

Concanavalin A distorts the beta-GlcNAc-(1-->2)-Man linkage of beta- GlcNAc-(1-->2)-alpha-Man-(1-->3)-[beta-GlcNAc-(1-->2)-alpha-Man- (1-- >6)]-Man upon binding

Carbohydrate recognition by proteins is a key event in many biological processes. Concanavalin A is known to specifically recognize the pentasaccharide core (beta-GlcNAc-(1-->2)-alpha- Man-(1-->3)-[beta- GlcNAc-(1-->2)-alpha-Man-(1-->6)]-Man) of N-linked oligosaccharides with a Ka of 1.41 x 10(6 )M-1. We have determined the structure of concanavalin A bound to beta-GlcNAc-(1-->2)-alpha-Man-(1-->3)-[beta- GlcNAc-(1-->2)-alpha-Man- (1-->6)]-Man to 2.7A. In six of eight subunits there is clear density for all five sugar residues and a well ordered binding site. The pentasaccharide adopts the same conformation in all eight subunits. The binding site is a continuous extended cleft on the surface of the protein. Van der Waals interactions and hydrogen bonds anchor the carbohydrate to the protein. Both GlcNAc residues contact the protein. The GlcNAc on the 1-->6 arm of the pentasaccharide makes particularly extensive contacts and including two hydrogen bonds. The binding site of the 1-->3 arm GlcNAc is much less extensive. Oligosaccharide recognition by Con A occurs through specific protein carbohydrate interactions and does not require recruitment of adventitious water molecules. The beta-GlcNAc-(1-->2)-Man glycosidic linkage PSI torsion angle on the 1-->6 arm is rotated by over 50 degrees from that observed in solution. This rotation is coupled to disruption of interactions at the monosaccharide site. We suggest destabilization of the monosaccharide site and the conformational strain reduces the free energy liberated by additional interactions at the 1-->6 arm GlcNAc site.      

Design and applicability of DNA arrays and DNA barcodes in biodiversity monitoring

Background  

The rapid and accurate identification of species is a critical component of large-scale biodiversity monitoring programs. DNA arrays (micro and macro) and DNA barcodes are two molecular approaches that have recently garnered much attention. Here, we compare these two platforms for identification of an important group, the mammals.     

Racializing teenage pregnancy: 'culture' and 'tradition' in the South African scientific literature

The signifiers, 'race', 'culture' or 'ethnicity' are utilized in the teenage pregnancy literature (1) to highlight 'differences' in adolescent sexual and reproductive behaviour and (2) as explanatory tools. When 'white' teenagers are the focus of research, psychological explanations are usually invoked, whereas for 'black' teenagers, explanations are socio-cultural in nature. In this article, we explore how, through a process of racialization, the psychomedical literature on teenage pregnancy in South Africa contributes to the entrenchment of 'race', 'culture' and 'ethnicity' as fixed, 'natural' signifiers. We utilize Derrida's notion of différance , together with Phoenix and Woollett's adaptation - 'normalized absence/pathologized presence' - to indicate how 'black' people are cast as the Other, the pathologized presence which relies on the normalized absent trace, 'whiteness', for definition. We analyse how the notions of 'tradition' and 'culture' are deployed to sanitize or disguise the underlying racializing project. 'Black' is exoticized and rendered strange and thus open to scrutiny, monitoring and intervention. 'Culture' and 'tradition' appeal to the myth of origin, thus providing pseudohistorical explanations which essentialize and naturalize racialized collectivities.     

Tono Reservoir fishery contribution to poverty reduction among fishers in northern Ghana

Fishery characteristics and livelihood status of fishers at Tono Reservoir, Ghana, were investigated between January 2015 and June 2016. Data on fisher demography, fishing gears, fishing methods, perceptions of the state of fish stocks, management practices, income and consumption of fishers were obtained through structured interviews. Censuses of fishers and fishing gears were conducted through direct observation and counts. The population of fishers was 950 and the majority (74%) of the sampled respondents fell within the ages of 24–41 years. Gillnet, cast net, trap and hook and line were the four main gears utilised. Illegal methods of fishing observed included the use of mosquito nets (nets with mesh <1.0 cm) and the use of brewer’s waste (pito mash) as bait. Brycinus nurse, Synodontis spp., Parailia spiniserrata and Chrysichthys spp. were perceived to have disappeared from the reservoir. The fishers were unaware of the existence of any fisheries regulations, hence there was no adherence to management practices. Their daily income was derived mainly from fishing. The incidence of poverty among fishers was low (8%). The Tono Reservoir has a great potential for supporting livelihood if it is properly managed.     

Positive and negative modulation of H-ras transforming potential by mutations of phenylalanine-28

Conserved amino-acids of H-ras from residues 25 to 34 were mutated in human H-ras cDNA with a pre-existing valine-12 activating mutation ([V¹²]p21), and built into SV40-driven expression vectors. The influence of the introduced mutations was initially screened by transfection of Rat-1 cells to score foci of transformed cells. Nonconservative mutations of amino-acids 25 (tryptophan for glutamine), 27 (asparagine for histidine) and 34 (alanine for proline) did not abrogate the transforming potential of [V¹²]p21. The conservative mutation of phenylalanine-28 to tryptophan ([V¹²W²⁸]p21) was also still transforming. Significantly, in the absence of the valine-12 activating mutation, tryptophan-28-ras ([W²⁸]p21) was weakly transforming while, in contrast, [V¹²D²⁸]p21 was unable to transform Rat-1 cells and retarded cell growth. Analysis of the binding and dissociation of GTP and GDP to normal and mutated p21 expressed in Escherichia coli showed that [V¹²D²⁸]p21 and [D²⁸]p21 do not bind GTP. The dissociation rate of both GTP and GDP bound to [W²⁸]p21 is increased, suggesting a mechanism for its transforming potential in Rat-1 cells. These studies illustrate the importance of phenylalanine-28 in guanine nucleotide binding by p21 ^h-ras . The mutations described could be valuable tools in investigations of cellular signal transduction involving small GTP-binding proteins.