Who mixes with whom among men who have sex with men? Implications for modelling the HIV epidemic in southern India.

In India, the identity of men who have sex with men (MSM) is closely related to the role taken in anal sex (insertive, receptive or both), but little is known about sexual mixing between identity groups. Both role segregation (taking only the insertive or receptive role) and the extent of assortative (within-group) mixing are known to affect HIV epidemic size in other settings and populations. This study explores how different possible mixing scenarios, consistent with behavioural data collected in Bangalore, south India, affect both the HIV epidemic, and the impact of a targeted intervention. Deterministic models describing HIV transmission between three MSM identity groups (mostly insertive Panthis/Bisexuals, mostly receptive Kothis/Hijras and versatile Double Deckers), were parameterised with behavioural data from Bangalore. We extended previous models of MSM role segregation to allow each of the identity groups to have both insertive and receptive acts, in differing ratios, in line with field data. The models were used to explore four different mixing scenarios ranging from assortative (maximising within-group mixing) to disassortative (minimising within-group mixing). A simple model was used to obtain insights into the relationship between the degree of within-group mixing, R0 and equilibrium HIV prevalence under different mixing scenarios. A more complex, extended version of the model was used to compare the predicted HIV prevalence trends and impact of an HIV intervention when fitted to data from Bangalore. With the simple model, mixing scenarios with increased amounts of assortative (within-group) mixing tended to give rise to a higher R0 and increased the likelihood that an epidemic would occur. When the complex model was fit to HIV prevalence data, large differences in the level of assortative mixing were seen between the fits identified using different mixing scenarios, but little difference was projected in future HIV prevalence trends. An oral pre-exposure prophylaxis (PrEP) intervention was modelled, targeted at the different identity groups. For intervention strategies targeting the receptive or receptive and versatile MSM together, the overall impact was very similar for different mixing patterns. However, for PrEP scenarios targeting insertive or versatile MSM alone, the overall impact varied considerably for different mixing scenarios; more impact was achieved with greater levels of disassortative mixing.

A new genus, Perplexacara, and new generic placements of species of Australian marsh beetles (Coleoptera: Scirtidae) based on morphology and molecular genetic data.

The Australian Scirtidae species previously identified as misplaced in the widespread genus Prionocyphon Redtenbacher are revisited as well as their possible relationship with the Australian genus Macrodascillus (Lea) using sequence data from the mitochondrial gene, cytochrome oxidase subunit 1 and two nuclear genes, elongation factor 1-alpha and Topoisomerase. The study confirmed the conclusion of Cooper et al. (2014) that the species did not belong in Prionocyphon. The study also included a species from each of three possibly related genera, Chameloscyphon Watts, Daploeuros Watts and Dasyscyphon Watts. Chameloscyphon huonensis Watts, Dasyscyphon victoriaensis Watts and Daploeuros lamingtonensis Watts were recovered as separate lineages with C. huonensis linking with Das. victoriaensis and Dap. lamingtonensis isolated. The species previously included in Prionocyphon were shown to belong in two genera, Macrodascillus and a new genus Perplexacara: Perplexacara caementum (Watts) new combination, P. latusmandibulara (Watts) new combination, P. macroflavida (Watts) new combination, Macrodascillus scalaris (Lea), M. insolitus (Watts) new combination and M. lamingtonensis (Watts) new combination.

New genera, species and combinations in the Pseudomicrocara Armstrong group (Coleoptera: Scirtidae) based on morphology supported by mitochondrial and nuclear gene sequence data.

The Australian Scirtidae genus Pseudomicrocara Armstrong, previously shown to be polyphyletic, is revised using both morphology and sequence data from the mitochondrial gene cytochrome oxidase subunit 1 and two nuclear genes, elongation factor 1-alpha and topoisomerase. Twenty-three genera, 16 of which are new, are recognised based on morphology, primarily of the mandibles and maxillary palpi, and male and female genitalia. Maximum likelihood and Bayesian phylogenetic analyses were used to examine relationships among species from 21 of the 23 recognised genera. Fifteen of the genera were recovered as distinct lineages. A further six, Accolabass Watts, Anocyphon gen. nov., Copiacyphon gen. nov., Nasutuscyphon gen. nov., Pseudomicrocara and Saprocyphon gen. nov. were considered to be genera based on both morphology and phylogenetic analysis but their species composition is uncertain and will require more work to confirm. The 17 new genera are fully described, keys are provided to all the genera in the Pseudomicrocara group, and to all the species in the genera Copiacyphon gen. nov., Spilotocyphon gen. nov., Accolabass Watts, Saltuscyphon gen. nov. and Vadumcyphon gen. nov. The male aedeagi of all new genera and species are illustrated, as are the female prehensors of some species.                The following genera are described as new: Alpestriscyphon gen. nov., Anthocara gen. nov., Anocyphon gen. nov., Copiacyphon gen. nov., Furcacyphon gen. nov., Latuscara gen. nov., Pictacara gen. nov., Nasutuscyphon gen. nov., Nektriscyphon gen. nov., Pumiliocara gen. nov., Ruborcara gen. nov., Saltuscyphon gen. nov., Saprocyphon gen. nov., Sisyracyphon gen. nov., Spilotocyphon gen. nov., Tenebriocyphon gen. nov. and Vadumcyphon gen. nov. A total of 45 new combinations are proposed. The following species are described as new: Accolabass monteithi sp. nov.; Alpestriscyphon bartlefrere sp. nov., Al. spurgeon sp. nov.; Anocyphon lepus sp. nov.; Copiacyphon brindaleensis sp. nov., C. cardinalis sp. nov., C. dytikos sp. nov.; Pumiliocara peneparva sp. nov.; Ruborcara saintae sp. nov.; Saltuscyphon montanus sp. nov., Sal. teraniaensis sp. nov.; Saprocyphon bithongensis sp. nov.; Sisyracyphon brisbanensis sp. nov., S. bulburinensis sp. nov.; Spilotocyphon occidentalis sp. nov., Sp. orientalis sp. nov., Sp. zwicki sp. nov.; Vadumcyphon centralis sp. nov., V. rugosus sp. nov. A checklist of all Australian taxa in the redefined Pseudomicrocara group is included.                Sequence data of the Argentinian species Pseudomicrocara antarctica (Fairmaire) is included. Phylogenetic analyses place this species as a distinct lineage within the Pseudomicrocara group.

How much could a microbicide's sexually transmitted infection efficacy contribute to reducing HIV risk and the level of condom use needed to lower risk? Model estimates.

OBJECTIVE: This study explores the potential contribution of a microbicide's sexually transmitted infection (STI) efficacy in reducing a female sex worker's (FSW) risk of STI and HIV infection. The study then investigates whether the threshold for the reduction in condom use following microbicide introduction that can be tolerated without increasing HIV risk is affected by STI efficacy. METHODS: A dynamic model describing the transmission of a bacterial STI between FSW and their clients was coupled with a static HIV model. The model uses data from Cotonou, Benin (1998-9), for illustration, to estimate the change in risk following the introduction of 50% HIV efficacious microbicides of different STI efficacies, used in 50% of sex acts when a condom is not used. The condom migration thresholds were estimated. The degree to which the findings are influenced by STI prevalence was explored. RESULTS: For highly transmissible STI, there is a non-monotonic relationship between STI prevalence and microbicide impact on HIV with the relative reduction in HIV risk first increasing, due to the proportion of HIV risk attributable to the STI increasing, but then decreasing at high prevalences as the STI becomes harder to control. A less transmissible STI can still be impacted upon with a moderate/high STI efficacy microbicide even at high STI prevalences. This relationship is also reflected in the condom migration thresholds. CONCLUSIONS: A microbicide's STI efficacy may have a substantial impact on STI and HIV incidence among high-risk groups. The variation in the condom migration thresholds for different STI efficacies and STI prevalences may be difficult to measure accurately.

A systematic review of published evidence on intervention impact on condom use in sub-Saharan Africa and Asia.

OBJECTIVE: There has been much debate about the value of condoms in HIV/STI programming. This should be informed by evidence about intervention impact on condom use, but there is limited compiled literature. This review aims to quantify intervention impact on condom use in sub-Saharan Africa and Asia, in different types of partnership. METHODS: A systematic review was conducted of papers published between 1998 and 2006 presenting evaluations of interventions involving condom promotion in sub-Saharan Africa and Asia. Data on reported postintervention levels of condom use, and various measures of changes in condom use, by partnership type, were compiled. RESULTS: A total of 1374 abstracts were identified. Sixty-two met the inclusion criteria (42 reporting significant increases in condom use): 44 from sub-Saharan Africa and 18 from Asia. Many (19) reported on condom use in commercial sex (15 significant), six on use with casual partners (three significant), 11 on use in marital/steady partnerships (nine significant), 14 on use by youths (eight significant) and 20 combined partnership types (11 significant). There is substantial evidence of interventions targeted at sex workers and clients achieving large increases in condom use. Far less evidence exists of intervention impact on condom use in casual relationships. In primary partnerships, postintervention condom use was low unless one partner was knowingly HIV-infected or at high-risk, or avoiding pregnancy. Evaluations of interventions targeting youths recorded limited increases in condom use. CONCLUSIONS: The findings illustrate the range of evidence about postintervention condom use in different partnerships, and how patterns of use are influenced by partnership type and perceptions of risk. Where possible, intervention studies should also assess biological endpoints, since prevention of infection is the measure of most interest in the evaluation of condom promotion interventions.

Heterogeneities in transmission rates and the epidemiology of schistosome infection.

Previous theoretical studies have suggested that heterogeneities in transmission rates can have significant effects on the epidemiology of parasite infections. However, the magnitude of these effects in practice remains uncertain because of the difficulty of quantifying such heterogeneities under natural conditions. In this paper we consider the effects of heterogeneous rates of contact with infective water bodies on the basic reproductive rate, R0, of human schistosomes. In particular, we examine the theoretical effects of differences in the distribution of contacts among individuals and among sites. We find that an individual's contribution to R0 depends not only on the net contact rate but also on how these contacts are distributed among sites--the contact pattern. Our analysis of field data suggests a substantial impact of heterogeneous contact rates on R0 in practice. Significant reductions in R0 may be possible if schistosomiasis control efforts are targeted at certain sites and, especially, certain individuals.

Violence against women: a neglected public health issue in less developed countries.

Violence against women is a significant public health issue in countries of both the industrialized and less developed world. This paper describes the magnitude and health consequences of domestic violence and rape, with an emphasis on developing countries; it recognizes, however, that there is a dearth of documentation regarding the wide range of activity opposing violence against women which is taking place in less developed countries. It briefly explores the factors that perpetuate violence against women and the strategies that have evolved to respond to the problem. It analyses the constellation of factors that may assist violence to emerge as a legitimate public health concern, and explores opportunities and obstacles to further progress in this field. Particular attention is devoted to the role of research in the policy-making process; research areas which may assist those opposing violence against women in all its forms are tentatively suggested.

The influence of concurrent partnerships on the dynamics of HIV/AIDS.

Most models of the spread of HIV/AIDS assume that the probability of transmission from an infected individual to a susceptible partner has some constant value per sexual act, compounding independently randomly (so that ten acts with one person chosen from a particular group has, on average, the same risk as one act with each of ten different people from that group). Guided by available data, other models treat the transmission process as being some characteristic (but highly variable) value per partnership, independent of the number of acts. This latter approach does not allow for the possible effects of concurrent partnerships, and therefore does not take account of the possibility that an initially uninfected partner of a given susceptible individual may become infected over the duration of their partnership. We present a new model, based on transmission per partnership, that takes account of partnership duration. If the number of overlapping partnerships is high enough (so that R0 greater than 1 among "standing crops" of partners), any initial infection will spread very fast--on the time scale of a few times the latent interval (a few months)--among existing networks of partners. After this initial "fast phase," the subsequent epidemic proceeds more slowly along conventional lines as new partnerships are formed. These properties of the model are illustrated numerically and by analytic studies (using singular perturbation theory). The possibility of such "two time-scale" phenomena could have implications for data analysis based on statistical back-projection.

Ultrastructure of Sarcocystis spp. (Protozoa: Apicomplexa) in rodents from North Sulawesi and West Java, Indonesia.

Tissue cysts of the protozoan genus Sarcocystis were detected in the skeletal muscles of 16 (40%) of 40 wild rodents captured in North Sulawesi and West Java, Indonesia. Two types of cysts were found to differ in their morphological characteristics. Macroscopic and microscopic cysts bounded by thick radially-striated cyst walls were detected at both locations in a total of 13 rodents belonging to seven different species (Bunomys chrysocomus, B. fratrorum, Maxomys bartelsii, M. musschenbroekii, Paruromys dominator, Rattus xanthurus and R. exulans). The primary cyst walls contained numerous broad spatula-like protrusions and the cysts were identified as S. singaporensis Zaman and Colley, 1976. In contrast, microscopic cysts bounded by thin smooth cyst walls were detected in seven rodents belonging to three different species captured at Toraut in North Sulawesi (B. chrysocomus, B. fratrorum and P. dominator). Ultrastructural examination revealed numerous slender hair-like protrusions of their primary cyst walls. It is proposed that these cysts be named S. sulawesiensis sp. n. on the basis of their unique morphological characteristics, their intermediate host range and their limited geographic distribution. Mixed infections by both species were found in three rodent species (B. chrysocomus, B. fratrorum and P. dominator).

Heterochromatin variation in the Australian rodent Uromys caudimaculatus.

Ten individuals of Uromys caudimaculatus sampled from Queensland gave evidence for the occurrence of two distinct chromosome races characterised by marked differences in their pattern of C-banding. In all four individuals from the north, thirteen of the twenty three chromosome which make up the standard haploid set had substantial distal C-blocks in addition to the smaller centric blocks which characterise all chromosomes other than the Y. Additionally two pairs had an interstitial block. By contrast none of the six southern individuals had fixed distal blocks though all of them except the Y carry pro-centric C-blocks and again one pair showed an interstitial block. The southern karyotype was, however, characterised by the presence of from six to nine mitotically stable supernumerary chromosomes all of which were totally C-positive despite the fact that at least five morphologically distinguishable types have been defined. While the relationship of these two types of constitutive heterochromatin remains to be clarified the large amount present in both northern and southern animals suggests that heterochromatin plays an important role in the basic biology of this species.

Polymorphism of the X-chromosome, Y-chromosome and autosomes in the Australian hopping mice, Notomys alexis, N. cervinus and N. fuscus (rodentia, muridae).

All three species of Notomys so far studied possess a diploid number of 48. Many elements in the karyotype of N. alexis are polymorphic due to variation in heterochromatin, but the variation is most marked in autosomal pair 1, which occurs in at least four forms, the X-chromosome, which occurs in three forms, and the Y-chromosome which occurs in many forms. N. cervinus is unique in the genus in possessing an entirely biarmed karyotype due mainly to the addition of heterochromatic short arms. The X-chromosome of N. cervinus occurs in three forms and the Y-chromosome in two forms. The karyotype of N. fuscus is mainly telocentric although two autosomal pairs are polymorphic due to pericentric inversions. The X- and Y-chromosomes both occur in two forms in N. fuscus. Chromosome measurements and C-banding show that most of the variation in the size and morphology of the sex-pair both within and between species is due to variation in constitutive heterochromatin.

Genetic similarities and differences between sublines of certain inbred strains of mice held within Australia.

Inbred mice of the strains C57B1/6, CBA, C3H, Balb/c and DBA/2 from a total of 17 different sources within Australia were compared, utilizing 12 different blood proteins and a morphometric analysis of a series of lower jaws. Evidence for genetic differentiation between sublines was found in only two cases. Evidence for the recent contamination of an inbred strain with another stock was found in one case.

Enzyme markers in inbred rat strains: genetics of new markers and strain profiles.

Twenty-six inbred strains of the laboratory rat (Rattus norvegicus) were examined for electrophoretic variation at an estimated 97 genetic loci. In addition to previously documented markers, variation was observed for the enzymes aconitase, aldehyde dehydrogenase, and alkaline phosphatase. The genetic basis of these markers (Acon-1, Ahd-2, and Akp-1) was confirmed. Linkage analysis between 35 pairwise comparisons revealed that the markers Fh-1 and Pep-3 are linked. The strain profiles of the 25 inbred strains at 11 electrophoretic markers are given.

Morphological evidence of apoptosis and the prevalence of apoptotic versus mitotic cells in the membrana granulosa of ovarian follicles during spontaneous and induced atresia in ewes.

Apoptosis is a process by which granulosa cells are thought to be deleted during ovarian follicular atresia. The aims of the present studies, using sheep as the experimental model, were to determine 1) whether morphological changes in cells composing the membrana granulosa during the process of atresia conformed with the general criteria of apoptotic cell death as assessed using tissue sections stained with hematoxylin and eosin; 2) whether cells classified as apoptotic on the basis of their morphology contained fragmented DNA using an in situ 3' end-labeling technique; and 3) the degree of apoptosis and mitosis within the granulosa cell populations of large antral follicles (> or = 3 mm in diameter) during both spontaneous and experimentally induced atresia using stereological methods. The results showed that most degenerate granulosa cells in follicles undergoing atresia display the morphological characteristics of apoptosis, suggesting that this is the most common pathway of cell deletion. Typical features were cells containing nuclei with marginated chromatin; cells with a single small densely staining nucleus (pyknotic appearance); cells with multiple smaller, densely staining nuclear fragments; and densely staining membrane-bound bodies (apoptotic bodies) either singly or in clusters. Cells with morphological features more typical of oncosis or necrosis were sometimes observed, but mainly during the later stages of atresia. All cells classified as apoptotic on the basis of morphological criteria contained fragmented DNA as measured by 3' end-labeling. Apoptotic bodies and/or cells were found in all follicles examined, including those classified as healthy. The overall prevalence of apoptotic cells plus apoptotic bodies expressed as a percentage of the total granulosa cell number per follicle varied from 0.02% to 0.20% in healthy follicles, varied from 0.21% to 2.00% in follicles in early (primary) atresia, and was > 2.0% in follicles in later (secondary) atresia. Percentages of mitotic cells in healthy follicles were > 0.5% in all but one of those examined and were < 1.0% in all follicles classified as atretic. Both morphological and 3' end-labeling results indicated that apoptotic cells were widely disseminated throughout the membrana granulosa, including the cell layer adjacent to the basement membrane. Collectively, these observations indicate that during early atresia, apoptosis occurs randomly and is not limited to specific areas within follicles. Our finding that apoptotic cell death and mitosis occur simultaneously within the same follicle is consistent with the notion that atresia is determined by a dynamic equilibrium between cell division, differentiation, and death.

Heterogeneities in the transmission of infectious agents: implications for the design of control programs.

From an analysis of the distributions of measures of transmission rates among hosts, we identify an empirical relationship suggesting that, typically, 20% of the host population contributes at least 80% of the net transmission potential, as measured by the basic reproduction number, R0. This is an example of a statistical pattern known as the 20/80 rule. The rule applies to a variety of disease systems, including vector-borne parasites and sexually transmitted pathogens. The rule implies that control programs targeted at the "core" 20% group are potentially highly effective and, conversely, that programs that fail to reach all of this group will be much less effective than expected in reducing levels of infection in the population as a whole.