Hawkmoth pollination of Bonatea speciosa (Orchidaceae) in a South African coastal forest

Hawkmoths ( Theretra capensis and Hyles lineata livornica ) pollinated the orchid Bonatea speciosa at a forested site along the southern Cape coast of South Africa. The flowers of B. speciosa are strongly evening-scented and hawkmoth activity was confined to a short period of 40 minutes after dusk on each evening of observation. The pollinaria are exceptionally elongated (c. 20 mm in length) and are affixed to the eyes of the hawkmoths. Pollinaria attached to feeding hawkmoths are brushed over the long stigmatic arms which project in front of flowers. The flowers of B. speciosa have a toothlike process at the mouth of the spur which forces moths to enter the flower from either side. As a result, only one of the pollinaria is removed from the flower during a visit. The division of the flower into two functional units by the toothlike process in the spur distinguishes the floral mechanism of B. speciosa from other Habenariinae.     

Airspora Measured in a Paddy Field in West Bengal,India

Aeromycoflora studies above an “Aman” variety of paddy (Oryza saliva L.) were carried out for two consecutive seasons, in 1990 and 1991, in the vicinity of Barrackpore, West Bengal, by means of the culture plate exposure technique. A more or less uniform spore concentration was observed during the early part of the vegetative stages in 1990 with an abrupt increase and peak during the maximum vegetative growth period. In 1991, a uniform spore count was found up until the flowering stages. A gradual increase in spore count after flowering was recorded in both seasons with the highest peaks during harvesting, followed by a sudden decrease after the harvest. The dominant genera isolated were Aspergillus, Currularia, Cladosporium and Penicillium. Aspergillus appeared in high concentrations from the very beginning of the crop season up to the flowering stages, with a gradual fall after flowering, while Cladosporium showed the reverse pattern. Currularia and Penicillium occurred regularly throughout the crop season.

Phytopathogenic types were represented by Helminthosporium oryzae, Fusarium, Altemaria and Nigrospora. Helminthosporium oryzae appeared in the air when the plants attained appreciable vegetative growth, being seen as “brown spots” on the foliage, and reaching peak concentration during harvesting. Fusarium in contrast to Altemaria appeared regularly in the air except during the later part of vegetative growth. Nigrospora was recorded only occasionally. A considerable number of “Sterile Forms” were present throughout both seasons.     

FXIIIA subtypes in Indonesians, Bangladeshis, Tibetans, South African blacks and South African whites

The polymorphism of FXIIIA was investigated in 105 Indonesians, 141 Bangladeshis, 186 Tibetans, 101 South African Blacks and 100 South African Whites using isoelectric focusing followed by immunoblotting. These population data conformed to the Hardy-Weinberg equilibrium. A circum-pan-Pacific cline in the FXIII*1A (or FXIII*1B) allele frequency appeared to exist among the Mongoloids.     

Termites of a South African savanna

Summary Cellulose toilet roll baits were exposed in three different subhabitats at Nylsvley Reserve, northern Transvaal, and respective attacks by up to eight species of termites are described and illustrated. In broad-leaved savanna attack was principally by Microcerotermes, a slow feeder that attacked rolls throughout the year, finding about half the rolls exposed each season. In Acacia savanna attack was largely by Microtermes, a fast feeder active only at wetter times of year. In open, grassy areas there was relatively little attack, except sporadically by Macrotermes which consumed whole rolls within a day or two. Bush-fires delayed initial attack on rolls, perhaps because reduced surface litter gave less protection to soil. The amount of each roll eaten during the trials is shown in histograms; it was consistently greater in Acacia than in broad-leaved savanna. The soil-feeding termites Aganotermes and Promirotermes were attracted during the wet season to the undersides of rolls, perhaps as a source of organic-rich soil (or possibly of water).     

Burden of new and recurrent tuberculosis in a major South African city stratified by age and HIV-status

Aim

To describe the burden of tuberculosis (TB) in Cape Town by calculating TB incidence rates stratified by age and HIV-status, assessing the contribution of retreatment disease and estimating the cumulative lifetime TB risk in HIV-negative individuals.

Methods

Details of TB cases were abstracted from the 2009 electronic TB register. Population denominators were estimated from census data and actuarial estimates of HIV prevalence, allowing calculation of age-specific and HIV-stratified TB notification rates.

Results

The 2009 mid-year population was 3,443,010 (3,241,508 HIV-negative and 201,502 HIV-positive individuals). There were 29,478 newly notified TB cases of which 56% were laboratory confirmed. HIV status was recorded for 87% of cases and of those with known HIV-status 49% were HIV-negative and 51% were positive. Discrete peaks in the incidence of non-HIV-associated TB occurred at three ages: 511/100,000 at 0–4 years of age, 553/100,000 at 20–24 years and 628/100,000 at 45–49 years with 1.5%, 19% and 45% being due to retreatment TB, respectively. Only 15.5% of recurrent cases had a history of TB treatment failure or default. The cumulative lifetime risks in the HIV-negative population of all new TB episodes and new smear-positive TB episodes were 24% and 12%, respectively; the lifetime risk of retreatment disease was 9%. The HIV-positive notification rate was 6,567/100,000 (HIV-associated TB rate ratio = 17). Although retreatment cases comprised 30% of the HIV-associated TB burden, 88% of these patients had no history of prior treatment failure or default.

Conclusions

The annual burden of TB in this city is huge. TB in the HIV-negative population contributed almost half of the overall disease burden and cumulative lifetime risks were similar to those reported in the pre-chemotherapy era. Retreatment TB contributed significantly to both HIV-associated and non-HIV-associated TB but infrequently followed prior inadequate treatment. This likely reflects ongoing TB transmission to both HIV-negative and positive individuals.     

Knowledge of HIV Serodiscordance,Transmission, and Prevention among Couples in Durban,South Africa

Objective

Couples’ voluntary HIV counseling and testing (CVCT) significantly decreases HIV transmission within couples, the largest risk group in sub-Saharan Africa, but it is not currently offered in most HIV testing facilities. To roll out such an intervention, understanding locale-specific knowledge barriers is critical. In this study, we measured knowledge of HIV serodiscordance, transmission, and prevention before and after receipt of CVCT services in Durban.

Design

Pre- and post-CVCT knowledge surveys were administered to a selection of individuals seeking CVCT services.

Methods

Changes in knowledge scores were assessed with McNemar Chi-square tests for balanced data and generalized estimating equation methods for unbalanced data.

Results

The survey included 317 heterosexual black couples (634 individuals) who were primarily Zulu (87%), unemployed (47%), and had at least a secondary level education (78%). 28% of couples proved to be discordant. Only 30% of individuals thought serodiscordance between couples was possible pre‐CVCT compared to 95% post-CVCT. One-third thought there was at least one benefit of CVCT pre‐CVCT, increasing to 96% post‐CVCT. Overall, there were positive changes in knowledge about HIV transmission and prevention. However, many respondents thought all HIV positive mothers give birth to babies with AIDS (64% pre-CVCT, 59% post-CVCT) and that male circumcision does not protect negative men against HIV (70% pre-CVCT, 67% post-CVCT).

Conclusions

CVCT was well received and was followed by improvements in understanding of discordance, the benefits of joint testing, and HIV transmission. Country-level health messaging would benefit from targeting gaps in knowledge about serodiscordance, vertical transmission, and male circumcision.     

Airspora of johannesburg and pretoria,south africa, 1987/88

The possibility of forecasting the occurrence of seasonal alleregens was investigated, using multiple stepwise regression analysis. Airspora data were collected with Burkard traps during 1987 and 1988. Grass pollen and fungal spores in the cities of Johannesburg and Pretoria were considered. Meteorological factors used were maximum and minimum temperatures, rainfall, relative humidity, sunhours, radiation, windspeed and pressure. In Johannesburg rain and sunhours were of primary importance for grass pollen, while windspeed at 14h00 and minimum temperature were the most significant parameters in Pretoria. For fungal spores, pressure and windspeed at 20h00 were most important in Johannesburg, with rain being the primary factor in Pretoria. This marked variability is probably attributable to climatic differences between the two cities. Although they are situated only seventy kilometres apart, Johannesburg lies within the grasslands of the Bankenveld, and Pretoria borders on the warmer savanna of the Bushveld.     

Factors Associated with Self-Reported Repeat HIV Testing after a Negative Result in Durban,South Africa

Background

Routine screening for HIV infection leads to early detection and treatment. We examined patient characteristics associated with repeated screening in a high prevalence country.

Methods

We analyzed data from a cohort of 5,229 adults presenting for rapid HIV testing in the outpatient departments of 2 South African hospitals from November 2006 to August 2010. Patients were eligible if they were ≥18 years, reported no previous diagnosis with HIV infection, and not pregnant. Before testing, participants completed a questionnaire including gender, age, HIV testing history, health status, and knowledge about HIV and acquaintances with HIV. Enrollment HIV test results and CD4 counts were abstracted from the medical record. We present prevalence of HIV infection and median CD4 counts by HIV testing history (first-time vs. repeat). We estimated adjusted relative risks (ARR’s) for repeat testing by demographics, health status, and knowledge of HIV and others with HIV in a generalized linear model.

Results

Of 4,877 participants with HIV test results available, 26% (N = 1258) were repeat testers. Repeat testers were less likely than first-time testers to be HIV-infected (34% vs. 54%, p<0.001). Median CD4 count was higher among repeat than first-time testers (201/uL vs. 147/uL, p<0.001). Among those HIV negative at enrollment (N = 2,499), repeat testing was more common among those with family or friends living with HIV (ARR 1.50, 95% CI: 1.33–1.68), women (ARR: 1.24, 95% CI: 1.11–1.40), and those self-reporting very good health (ARR: 1.28, 95% CI: 1.12–1.45).

Conclusions

In this high prevalence setting, repeat testing was common among those undergoing HIV screening, and was associated with female sex, lower prevalence of HIV infection, and higher CD4 counts at diagnosis.     

Cardiac allografts: a 24-year South African experience

The history of using homologous cardiac valves dates back more than 30 years. Through the years emphasis was placed on the optimization of graft retrieval, preservation techniques and clinical application. A cardiac homograft valve bank was established at the Department of Cardiothoracic Surgery, University of the Free State, Bloemfontein in 1982. A retrospective analysis was performed on all allograft data since 1984. Since the first valve was successfully procured and transplanted in 1984, 2,540 aortic and pulmonary homografts were harvested from 1,792 donors, of which 1,545 [989 (64%) aortic and 556 (36%) pulmonary] were released for clinical use. Valves were discarded for various reasons, the main reasons being Human Immunodeficiency Virus (32.4%), Hepatitis B (9.6%) and venereal diseases (8.9%). The mean donor age was 26.98 years with a male predominance of 1,368 males versus 424 females. The average ischemic time was 33 h mainly due to medico-legal autopsies exceeding the desired 24 h time limit. The valves were disinfected in an antibiotic cocktail of Mefoxin, Piperacillin, Amikacin and Amphotericin B prior to cryopreservation. The surgical procedures utilizing the majority of homografts were aortic valve replacements (42.9%), aortic root replacements (19.3%) and right ventricular-pulmonary artery conduits (33.3%). The bank also supplied 23 other centers with homografts (402 aortic and 301 pulmonary). The Bloemfontein bank has established itself over the years as a viable and functional cardiac homograft bank. However, with increasing activity in the procurement arena and widened applications in the operating room the role of the homograft seems assured but availability still remains a major concern.     

Beetle assemblages of indigenous and alien decomposing fruit in subtropical Durban,South Africa

Ecological theory predicts that insect assemblages on indigenous plants will be more diverse than those on alien plants. However, this theory refers primarily to herbivores, and its applicability to decomposers is unclear. Here, we compare beetle assemblages from the fallen fruit of the two most common plants producing large fleshy fruit at our study site in Durban, South Africa: one indigenous African plant (the toad tree, Tabernaemontana ventricosa, Apocynaceae) and one invasive tropical American one (the granadilla, Passiflora edulis, Passifloraceae), at various stages of the decomposition process, thus spanning a continuum between herbivory and detritivory. Beetles found on the two plants included both alien (some categorized as pests of stored fruit) and indigenous species (including some localized endemics). We found that the mean diversity and abundance were not significantly different between the two plant species (with nine beetles from four morphospecies in the average sample) and that the beetle assemblages from the two plant species largely overlap. Statistical analyses suggested that other factors such as stage of fruit decomposition and seasonality could have greater influence on diversity and abundance than the provenance of the plant species. We conclude that insect–plant interactions in the emerging ecosystems that include indigenous and alien species in both groups are complex and that the importance of interactions between species of different provenances may have previously been underestimated.     

Drug-Resistant Tuberculosis among HIV-Infected Patients Starting Antiretroviral Therapy in Durban, South Africa

Objective

To estimate the prevalence of drug-resistant tuberculosis (TB) and describe the resistance patterns in patients commencing antiretroviral therapy (ART) in an HIV clinic in Durban, South Africa.

Design

Cross-sectional cohort study.

Methods

Consecutive HIV-infected adults (≥18y/o) initiating HIV care were enrolled from May 2007–May 2008, regardless of signs or symptoms of active TB. Prior TB history and current TB treatment status were self-reported. Subjects expectorated sputum for culture (MGIT liquid and 7H11 solid medium). Positive cultures were tested for susceptibility to first- and second-line anti-tuberculous drugs. The prevalence of drug-resistant TB, stratified by prior TB history and current TB treatment status, was assessed.

Results

1,035 subjects had complete culture results. Median CD4 count was 92/µl (IQR 42–150/µl). 267 subjects (26%) reported a prior history of TB and 210 (20%) were receiving TB treatment at enrollment; 191 (18%) subjects had positive sputum cultures, among whom the estimated prevalence of resistance to any antituberculous drug was 7.4% (95% CI 4.0–12.4). Among those with prior TB, the prevalence of resistance was 15.4% (95% CI 5.9–30.5) compared to 5.2% (95% CI 2.1–8.9) among those with no prior TB. 5.1% (95% CI 2.4–9.5) had rifampin or rifampin plus INH resistance.

Conclusions

The prevalence of TB resistance to at least one drug was 7.4% among adults with positive TB cultures initiating ART in Durban, South Africa, with 5.1% having rifampin or rifampin plus INH resistance. Improved tools for diagnosing TB and drug resistance are urgently needed in areas of high HIV/TB prevalence.     

PAHs,OCPs and PCBs in sediments from three catchments in Durban,South Africa

Polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were analysed from sediment samples collected in 2012 from rivers, surface runoff canals and estuaries in three highly urbanised catchments in durban, KwaZulu-Natal, South Africa. PAHs were ubiquitous, at concentrations between 36–6 800 ng g^?1 dry mass (dm). Congener ratio diagnosis suggests the PAHs were derived predominantly from pyrogenic sources. Four OCPs and/or their metabolites were detected at varying frequencies and concentrations. Of these, dichlorodiphenyltrichloroethane (ddT) and metabolites were most frequently detected and were at a high concentration in sediment in some systems. Toxaphene was detected at a high concentration at some sites. The total PCB concentration varied widely, from below the method detection limit to 110 ng g^?1 (dm). Based on the comparison of chemical concentrations to international sediment quality guidelines, PAH, OCP and PCB concentrations in most sediment samples posed a low risk to sediment-dwelling organisms. However, in some instances the risk was moderate or high. It is recommended that these compounds be monitored more frequently and comprehensively in aquatic ecosystems to better understand the ecological and human health implications.