In Vitro Effect of 5-Nitroimidazole Drugs against Trichomonas vaginalis Clinical Isolates

Infections with the sexually transmitted parasite Trichomonas vaginalis are normally treated with metronidazole, but cure rates are suboptimal and recurrence rates following treatment are high. Therefore, our objective was to assess the in vitro antitrichomonas activities of three other 5-nitroimidazole drugs and compare them with metronidazole. T. vaginalis isolates (n = 94) isolated from South African women presenting with vaginal discharge syndrome at two sexually transmitted disease clinics in KwaZulu-Natal were grown from frozen stock. Twofold serial dilutions (16 to 0.25 mg/L) of metronidazole, tinidazole, ornidazole, and secnidazole were prepared in Diamond's broth. The MICs were read after 48 h of anaerobic incubation at 37°C. An MIC of <2 mg/L was defined as susceptible, an MIC of 2 mg/L was defined as intermediate, and an MIC of >2 mg/L was defined as resistant. Sixty-one percent (57/94) of the T. vaginalis isolates were susceptible to metronidazole, 80% (75/94) were susceptible to tinidazole, 75% (71/94) were susceptible to secnidazole, and 89% (84/94) were susceptible to ornidazole. Resistance levels were 11%, 2%, and 1% for metronidazole, tinidazole, and secnidazole, respectively, while no resistance was observed for ornidazole. Intermediate scores were 28% for metronidazole, 18% for tinidazole, 24% for secnidazole, and 11% for ornidazole. Isolates from a proportion of women with bacterial vaginosis (BV) had higher MICs, and no isolates from women coinfected with another sexually transmitted infectious organism were resistant to any of the antimicrobials tested. This study showed that among T. vaginalis isolates in KwaZulu-Natal, there is no in vitro resistance to ornidazole. Of the 5-nitroimidazoles, metronidazole showed the highest level of resistance. The very low levels of resistance for the other three antimicrobials indicate that all three are viable options as a replacement for metronidazole if these in vitro findings are found to correlate with clinical outcomes. IMPORTANCE Trichomonas vaginalis is the most common nonviral sexually transmitted infection associated with reproductive sequelae and HIV acquisition risk worldwide. Despite its role in reproductive health, a high prevalence in South Africa, and the reported metronidazole resistance worldwide, no alternative regimens have been tested against T. vaginalis in our setting. This study compared the susceptibility patterns of three other 5-nitroiminazoles (secnidazole, tinidazole, and ornidazole), which are active against T. vaginalis with metronidazole in vitro. Metronidazole, the drug of choice for the treatment of trichomoniasis, showed the highest level of resistance, while the three regimens showed very low levels of resistance. These data indicate that all three are viable options as a replacement for metronidazole if these in vitro findings are found to correlate with clinical outcomes.

Stability of a monovalent rotavirus vaccine after exposure to different temperatures observed in KwaZulu-Natal, South Africa

Background

Rotavirus infection and its associated hospitalization of children less than 5 years old in middle- and low-income countries remains a public health challenge. We hypothesized that the Rotarix®potency is affected by non-optimal temperatures which translates into reduced vaccine effectiveness in these settings.

Objective

To assess the effect of non-optimal temperatures on the potency of the Rotarix® vaccine in South Africa.

Methods

Rotarix® vaccine was exposed to temperatures reflecting breaches in the cold chain. Vero cells (ATCC CCL-81) grown in a 24-well tissue culture plates were infected with Rotarix® vaccine viruses after exposure to non-optimal temperatures and the potency of the vaccine was determined using the plaque assay.

Results

Exposure of the Rotarix® vaccine to seasonal temperatures in KwaZulu-Natal for 6 hours and to extreme temperatures of 40oC for 72 hours as well as to −20°C and −80°C for 12 hours did not affect the potency of the vaccine beyond its expected standard of >7 x 10⁵ PFU/ml.

Conclusion

This study revealed that the Rotarix® vaccine remains potent even after exposure to non-optimal temperatures. However, this study only explored the effect of a constant ‘adverse’ temperature on vaccine potency and not the effect of temperature fluctuations.

Influence of vaccination status and clinical, seasonal and sociodemographic factors on rotavirus prevalence in KwaZulu-Natal, South Africa

Human rotavirus infection is the leading cause of diarrhoea in infants and young children worldwide. In South Africa, diarrhoea is a major cause of childhood morbidity and mortality in children less than five years old, and before the vaccine was introduced rotavirus had been reported as causing one-third of all diarrhoeal related hospital admissions. This study assessed factors influencing the prevalence of rotavirus in children aged five years and under in KwaZulu-Natal, South Africa between June 2014 and June 2015. In addition, genotypes of the rotaviruses were determined. A stool specimen was collected from children presenting with diarrhoea to a regional hospital. Clinical, vaccination status, seasonal and sociodemographic information was collected using a structured questionnaire. ELISA (enzyme linked immunosorbent assay) was performed to detect rotavirus antigen in the stool. Rotavirus from selected positives specimens were genotyped using RT–PCR (reverse transcriptase polymerase chain reaction). The data were analysed using SPSS. In total, 365 stool specimens were collected. Rotavirus antigen was detected in 83 (23%) patients. The prevalence of rotavirus was not affected by vaccination status (p = 0.3; OR 1.5; CI 0.7–3.1), HIV status (p = 0.2; OR 0.6; CI 0.2–1.5), breastfeeding (p = 0.9; OR 1.1; CI 0.5–2.5) and administration of anti-helminth treatment (p = 0.6; OR 0.8; CI 0.3–1.9). The highest rotavirus prevalence was observed in the winter season (p 0.001; OR 43.3; CI 14.9–125.0). The G9P[8] was the most prevalent genotype (21%) followed by G9P[4] (14%). Rotavirus remains a major contributor to childhood diarrhoeal aetiology and hospitalisation in KwaZulu-Natal. Further investigation is needed to better understand the key drivers of rotavirus infection despite a successful vaccination programme in South Africa.

An evaluation of infection control in private and public sector intensive care units in South Africa

Background

Appropriate infection control policies and practices are key to reducing the risk of healthcare-associated infections in patients in intensive care units (ICUs).

Objective

To evaluate infection control in ICUs using the Infection Control Assessment Tool (ICAT).

Methods

Six public and five private adult ICUs were included. Seven modules from the ICAT were administered including ICU, hand hygiene, and isolation and standard precautions. Modules were scored on a quantitative scale as per the tool guidelines and trained independent nurses observed practices.

Results

All ICUs reported to have a 1:1 nurse-to-patient ratio. One public ICU did not have the required 1:2 hand wash basin-to-bed ratio. We observed 100% adherence to handwashing or alcohol rub at each of the five moments of hand hygiene; however, the correct amount of alcohol rub was used in only 2% (n = 2) of the 117 observations. The median score for isolation and standard precautions was 79%.

Discussion

There was good infection control practice in ICUs. However, ICUs did not have isolation policies for all the infections listed in the ICAT and did not screen visitors to the ICU. We identified shortcomings in the ICAT and a more suitable tool is required for our healthcare setting.

Mechanisms of first-line antimicrobial resistance in multi-drug and extensively drug resistant strains of Mycobacterium tuberculosis in KwaZulu-Natal, South Africa

BACKGROUND

In South Africa, drug resistant tuberculosis is a major public health crisis in the face of the colossal HIV pandemic.

METHODS

In an attempt to understand the distribution of drug resistance in our setting, we analysed the rpoB, katG, inhA, pncA and embB genes associated with resistance to key drugs used in the treatment of tuberculosis in clinical isolates of Mycobacterium tuberculosis in the KwaZulu-Natal province.

RESULTS

Classical mutations were detected in the katG, inhA and embB genes associated with resistance to isoniazid and ethambutol. Diverse mutations were recorded in the multidrug resistant (MDR) and extensively drug resistant (XDR) isolates for the rpoB and pncA gene associated with resistance to rifampicin and pyrazinamide.

CONCLUSIONS

M.tuberculosis strains circulating in our setting display a combination of previously observed mutations, each mediating resistance to a different drug. The MDR and XDR TB isolates analysed in this study displayed classical mutations linked to INH and EMB resistance, whilst diverse mutations were linked to RIF and PZA resistance. The similarity of the XDR strains confirms reports of the clonality of the XDR epidemic. The successful dissemination of the drug resistant strains in the province underscores the need for rapid diagnostics to effectively diagnose drug resistance and guide treatment.

Minimal diversity of drug-resistant Mycobacterium tuberculosis strains, South Africa

Multidrug- (MDR) and extensively drug-resistant tuberculosis (XDR TB) are commonly associated with Beijing strains. However, in KwaZulu-Natal, South Africa, which has among the highest incidence and mortality for MDR and XDR TB, data suggest that non-Beijing strains are driving the epidemic. We conducted a retrospective study to characterize the strain prevalence among drug-susceptible, MDR, and XDR TB cases and determine associations between strain type and survival. Among 297 isolates from 2005–2006, 49 spoligotype patterns were found. Predominant strains were Beijing (ST1) among drug-susceptible isolates (27%), S/Quebec (ST34) in MDR TB (34%) and LAM4/KZN (ST60) in XDR TB (89%). More than 90% of patients were HIV co-infected. MDR TB and XDR TB were independently associated with mortality, but TB strain type was not. We conclude that, although Beijing strain was common among drug-susceptible TB, other strains predominated among MDR TB and XDR TB cases. Drug-resistance was a stronger predictor of survival than strain type.

Moxifloxacin resistance in the F15/LAM4/KZN extensively drug-resistant strain of Mycobacterium tuberculosis

Objectives

Moxifloxacin (MXF) has been advocated for the treatment of extensively drug-resistant (XDR) tuberculosis despite resistance to older-generation fluoroquinolones. We investigated the relationship between the minimum inhibitory concentration (MIC) of MXF and mutations in the gyrA and gyrB genes in Mycobacterium tuberculosis (MTB) isolates from KwaZulu-Natal (KZN) Province of South Africa.

Materials and methods

MICs of 56 MTB isolates were compared to the mutations in the quinolone resistance-determining region known to confer fluoroquinolone resistance. Isolates were genotyped by IS6110 restriction fragment length polymorphism analysis.

Results

The circulating F15/LAM4/KZN XDR strain circulating in KZN Province harbored the A90V mutation and displayed high-level resistance with MICs of 8 mg/L for ciprofloxacin and ofloxacin and ≥1 mg/L for MXF.

Conclusion

The inclusion of MXF in XDR-TB treatment regimens requires careful consideration in our setting, where clinical outcome data in MXF-containing regimens are unavailable.

Nosocomial transmission of extensively drug-resistant tuberculosis in a rural hospital in South Africa

BACKGROUND

Extensively drug-resistant tuberculosis (XDR-tuberculosis) is a global public health threat, but few data exist elucidating factors driving this epidemic. The initial XDR-tuberculosis report from South Africa suggested transmission is an important factor, but detailed epidemiologic and molecular analyses were not available for further characterization.

METHODS

We performed a retrospective, observational study among XDR-tuberculosis patients to identify hospital-associated epidemiologic links. We used spoligotyping, IS6110-based restriction fragment-length polymorphism analysis, and sequencing of resistance-determining regions to identify clusters. Social network analysis was used to construct transmission networks among genotypically clustered patients.

RESULTS

Among 148 XDR-tuberculosis patients, 98% were infected with human immunodeficiency virus (HIV), and 59% had smear-positive tuberculosis. Nearly all (93%) were hospitalized while infectious with XDR-tuberculosis (median duration, 15 days; interquartile range: 10-25 days). Genotyping identified a predominant cluster comprising 96% of isolates. Epidemiologic links were identified for 82% of patients; social network analysis demonstrated multiple generations of transmission across a highly interconnected network.

CONCLUSIONS

The XDR-tuberculosis epidemic in Tugela Ferry, South Africa, has been highly clonal. However, the epidemic is not the result of a point-source outbreak; rather, a high degree of interconnectedness allowed multiple generations of nosocomial transmission. Similar to the outbreaks of multidrug-resistant tuberculosis in the 1990s, poor infection control, delayed diagnosis, and a high HIV prevalence facilitated transmission. Important lessons from those outbreaks must be applied to stem further expansion of this epidemic.

Mycobacterium tuberculosis isolates grown under oxygen deprivation invade pulmonary epithelial cells

Mycobacterium tuberculosis has the ability to adapt to and survive under different environmental conditions, including oxygen deprivation. To better understand the pathogenesis of M. tuberculosis, we studied the invasion of human alveolar (A549) and human bronchial (BBM) epithelial cell lines by M. tuberculosis isolates cultured under oxygen deprivation. We used isolates belonging to the Beijing and F15/LAM4/KZN families, isolates with unique DNA fingerprints and the laboratory strains H37Rv and H37Ra. We determined that: (1) M. tuberculosis bacilli grown under oxygen deprivation invade epithelial cells, (2) the invasion capacity of all 17 isolates differed, and (3) oxygen deprivation influenced the invasion capacity of these isolates. All isolates invaded the A549 more effectively than the BBM cells. Three of the F15/LAM4/KZN isolates, two of which had extensively drug resistance (XDR) profiles, were at least twice as invasive (≥33%) as the most invasive Beijing isolate (15%) (P < 0.05). We conclude that for a more comprehensive understanding of the pathogenesis of M. tuberculosis, studies should include isolates that have been cultured under oxygen deprivation.

Symptomatic vaginal discharge is a poor predictor of sexually transmitted infections and genital tract inflammation in high-risk women in South Africa

BACKGROUND

Diagnosis and treatment of sexually transmitted infections (STIs) is a public health priority, particularly in regions where the incidence of human immunodeficiency virus (HIV) infection is high. In most developing countries, STIs are managed syndromically. We assessed the adequacy of syndromic diagnosis of STIs, compared with laboratory diagnosis of STIs, and evaluated the association between STI diagnosis and the risk of HIV acquisition in a cohort of high-risk women.

METHODS

HIV-uninfected high-risk women (n = 242) were followed for 24 months. Symptoms of STIs were recorded, and laboratory diagnosis of common STI pathogens was conducted every 6 months. Forty-two cytokines were measured by Luminex in cervicovaginal lavage specimens at enrollment. Human immunodeficiency virus type 1 (HIV-1) infection was evaluated monthly.

RESULTS

Only 12.3% of women (25 of 204) who had a laboratory-diagnosed, discharge-causing STI had clinically evident discharge. Vaginal discharge was thus a poor predictor of laboratory-diagnosed STIs (sensitivity, 12.3%; specificity, 93.8%). Cervicovaginal cytokine concentrations did not differ between women with asymptomatic STIs and those with symptomatic STIs and were elevated in women with asymptomatic STIs, compared with women with no STIs or bacterial vaginosis. Although laboratory-diagnosed STIs were associated with increased risk of HIV infection (hazard ratio, 3.3 [95% confidence interval, 1.5-7.2)], clinical symptoms were not.

CONCLUSIONS

Syndromic STI diagnosis dependent on vaginal discharge was poorly predictive of laboratory-diagnosed STI. Laboratory-diagnosed STIs were associated with increased susceptibility to HIV acquisition, while vaginal discharge was not.

Einstein Contained Aerosol Pulmonizer (ECAP): Improved Biosafety for Multi-Drug Resistant (MDR) and Extensively Drug Resistant (XDR) Mycobacterium tuberculosis Aerosol Infection Studies

A new apparatus enhances the biosafety of containment (biosafety level 3 [BSL-3]) and provides experimental reproducibility for aerosol infection experiments with MDR and XDR Mycobacterium tuberculosis. The methods are generally applicable to the study of airborne pathogens.

Increasing drug resistance in extensively drug-resistant tuberculosis, South Africa

We expanded second-line tuberculosis (TB) drug susceptibility testing for extensively drug-resistant Mycobacterium tuberculosis isolates from South Africa. Of 19 patients with extensively drug-resistant TB identified during February 2008–April 2009, 13 (68%) had isolates resistant to all 8 drugs tested. This resistance leaves no effective treatment with available drugs in South Africa.

Differences in Chlamydia trachomatis growth rates in human keratinocytes among lymphogranuloma venereum reference strains and clinical isolates

The pathogenesis of the primary stage of lymphogranuloma venereum (LGV) is poorly understood. There is no skin cell model and LGV pathogenesis studies are therefore carried out on cells of different origin. Moreover, such studies usually use reference strains, which may have evolved over the years in culture. In this study, a model was developed in which Chlamydia trachomatis enters and grows in human keratinocytes at 37 and 33 °C. Keratinocytes were infected with fresh clinical isolates and the three LGV reference strains L1, L2 and L3. Growth was monitored for 5 days post-infection using fluorescence microscopy and image analysis software. Chlamydial replication was quicker at 37 than at 33 °C, despite 33 °C being the temperature of human skin. The serovar L2 reference strain grew significantly faster than the other strains, although the fresh clinical isolates were also serovar L2. When grown in keratinocytes at 33 °C, the L2 and L3 reference strains produced much larger inclusions than the other strains tested. This model, which utilizes keratinocytes, better simulates the conditions present at the initial site of infection in LGV than previously published literature, making it a useful tool for future LGV pathogenesis studies. In addition, the results indicate that fresh clinical isolates should be included in LGV pathogenesis studies.

Spread of extensively drug-resistant tuberculosis in KwaZulu-Natal province, South Africa

BACKGROUND

In 2005 a cluster of 53 HIV-infected patients with extensively drug-resistant tuberculosis (XDR-TB) was detected in the Msinga sub-district, the catchment area for the Church of Scotland Hospital (CoSH) in Tugela Ferry, in KwaZulu-Natal province (KZN), South Africa. KZN is divided into 11 healthcare districts. We sought to determine the distribution of XDR TB cases in the province in relation to population density.

METHODS

In this cross-sectional study, the KZN tuberculosis laboratory database was analysed. Results of all patients with a sputum culture positive for Mycobacterium tuberculosis from January 2006 to June 2007 were included. Drug-susceptibility test results for isoniazid, rifampicin, ethambutol, streptomycin, kanamycin and ofloxacin were available for all patients as well as the location of the hospital where their clinical diagnosis was made.

FINDINGS

In total, 20858 patients attending one of 73 hospitals or their adjacent clinics had cultures positive for M. tuberculosis. Of these, 4170 (20%) were MDR-TB cases. Four hundred and forty three (11%) of the MDR tuberculosis cases displayed the XDR tuberculosis susceptibility profile. Only 1429 (34%) of the MDR-TB patients were seen at the provincial referral hospital for treatment. The proportion of XDR-TB amongst culture-confirmed cases was highest in the Msinga sub-district (19.6%), followed by the remaining part of the Umzinyati district (5.9%) and the other 10 districts (1.1%). The number of hospitals with at least one XDR-TB case increased from 18 (25%) to 58 (80%) during the study period.

INTERPRETATION

XDR-TB is present throughout KZN. More than 65% of all diagnosed MDR-TB cases, including XDR-TB patients, were left untreated and likely remained in the community as a source of infection.

Pyrido[1,2-a]benzimidazole-based agents active against tuberculosis (TB), multidrug-resistant (MDR) TB and extensively drug-resistant (XDR) TB

The struggle against tuberculosis (TB) is still far from over. TB, caused by Mycobacterium tuberculosis, is one of the deadliest infections worldwide. Co-infection with human immunodeficiency virus (HIV) and the emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) strains have further increased the burden for this disease. Herein, we report the discovery of 2-(4-chlorobenzyl)-3-methyl-1-oxo-1H,5H-pyrido[1,2-a]benzimidazole-4-carbonitrile as an effective antitubercular agent and the structural modifications of this molecule that have led to analogues with improved potency and lower toxicity. A number of these derivatives were also active at sub-micromolar concentrations against resistant TB strains and devoid of apparent toxicity to Vero cells, thereby underscoring their value as novel scaffolds for the development of new anti-TB drugs.

Nosocomial transmission of the F15/LAM4/KZN genotype of Mycobacterium tuberculosis in patients on tuberculosis treatment

SETTING

King George V (KGV) Hospital has the largest tuberculosis (TB) facility in KwaZulu-Natal (KZN), the province with the highest prevalence of TB-HIV (human immunodeficiency virus) co-infection in South Africa. During the study, KGV was the only provincial referral hospital for patients with drug-resistant TB.

OBJECTIVE

To determine the role of nosocomial transmission in patients infected with a new strain of Mycobacterium tuberculosis during treatment.

DESIGN

Insertion sequence 6110-DNA fingerprinting was performed on stored isolates from patients with culture-positive pulmonary TB for more than 6 weeks after treatment started and those who relapsed.

RESULTS AND CONCLUSION

DNA fingerprints of 14 of 26 patients with differing isolates matched those of other patients. Four of them acquired a F15/LAM4/KZN genotype, while two acquired fully susceptible Beijing strains. Three of the four F15/LAM4/KZN strains were multidrug-resistant with identical fingerprint patterns, while the fourth was fully susceptible. One of these was acquired during hospitalisation and three after discharge. Both HIV-infected and non-infected patients are at risk of infection with the F15/LAM4/KZN strain in health care facilities and within the community. Rapid diagnostic tests, separation of TB and non-TB patients on admission and isolation of multidrug-resistant and extensively drug-resistant TB patients are essential to curb nosocomial transmission.

Adhesion to and invasion of pulmonary epithelial cells by the F15/LAM4/KZN and Beijing strains of Mycobacterium tuberculosis

Globally, specific genotypes of Mycobacterium tuberculosis have been shown to dominate in patients, suggesting that these are more successful pathogens. One such genotype, the F15/LAM4/KZN (KZN) family of M. tuberculosis, has predominated in KwaZulu-Natal, South Africa, since the early 1990s. This strain recently evolved from multidrug-resistant to extensively drug-resistant (XDR). The ability of M. tuberculosis strains belonging to the Beijing family, the KZN family, strains with unique DNA fingerprint patterns and laboratory strains (H37Rv and H37Ra) to adhere to and invade a human alveolar (A549) and a human bronchial (BBM) epithelial cell line was investigated. All strains displayed greater adhesion to and invasion of A549 cells as compared to BBM cells. The Beijing and KZN strains combined showed greater adhesion (28 %) than the unique strains (5 %) (P <0.05). The XDR variant of KZN invaded A549 cells more effectively than the other isolates. These results suggest that the successful spread of the Beijing and KZN strains might be related to their interaction with alveolar epithelium.

Genome analysis of multi- and extensively-drug-resistant tuberculosis from KwaZulu-Natal, South Africa

The KZN strain family of Mycobacterium tuberculosis is a highly virulent strain endemic to the KwaZulu-Natal region of South Africa, which has recently experienced an outbreak of extensively-drug resistant tuberculosis. To investigate the causes and evolution of drug-resistance, we determined the DNA sequences of several clinical isolates--one drug-susceptible, one multi-drug resistant, and nine extensively drug-resistant--using whole-genome sequencing. Analysis of polymorphisms among the strains is consistent with the drug-susceptibility profiles, in that well-known mutations are observed that are correlated with resistance to isoniazid, rifampicin, kanamycin, ofloxacin, ethambutol, and pyrazinamide. However, the mutations responsible for rifampicin resistance in rpoB and pyrazinamide in pncA are in different nucleotide positions in the multi-drug-resistant and extensively drug-resistant strains, clearly showing that they acquired these mutations independently, and that the XDR strain could not have evolved directly from the MDR strain (though it could have arisen from another similar MDR strain). Sequencing of eight additional XDR strains from other areas of KwaZulu-Natal shows that they have identical drug resistant mutations to the first one sequenced, including the same polymorphisms at sites associated with drug resistance, supporting the theory that this represents a case of clonal expansion.

Exogenous reinfection as a cause of multidrug-resistant and extensively drug-resistant tuberculosis in rural South Africa

BACKGROUND

Multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) are now major threats in areas of South Africa with a high prevalence of TB and human immunodeficiency virus (HIV) infection. The role of exogenous reinfection as a cause of MDR and XDR TB in these settings has not been determined.

METHODS

We reviewed data from patients with culture-positive TB who later developed MDR or XDR TB in Tugela Ferry, KwaZulu-Natal, South Africa during 2005-2006. We performed spoligotyping on initial isolates (obtained at the time of treatment initiation) and follow-up isolates obtained from these patients.

RESULTS

We identified 23 patients who developed MDR or XDR TB after being treated for less resistant TB between June 2005 and June 2006. Both initial and follow-up isolates were available for spoligotyping for 17 of these patients. In all cases, the follow-up isolates' spoligotypes differed from those of the initial isolate, indicating exogenous reinfection. Two genotypes (shared type [ST] 34 and ST 60, associated with MDR and XDR TB, respectively) were responsible for 85% of reinfections. All 17 patients had been hospitalized; all 15 whose HIV infection status was known were HIV-infected.

CONCLUSIONS

Exogenous reinfection is an important mechanism for the development of MDR and XDR TB. In addition to strengthening TB treatment programs, effective infection control strategies are urgently needed to reduce the transmission of MDR and XDR TB.

Evidence for a clonally different origin of the two cholera epidemics of 2001-2002 and 1980-1987 in South Africa

Vibrio cholerae O1 serotype Ogawa and serotype Inaba isolates from the cholera epidemic that occurred in 2001 and 2002 in South Africa were compared with isolates of V. cholerae O1 serotype Inaba from the epidemic that occurred between 1980 and 1987. PFGE using NotI digestion was used to compare stored isolates received during the 1980s epidemic with those received during the epidemic in 2001/2002. A selected number of these isolates were then sequenced to compare the sequence of the wbeT gene in the V. cholerae O1 Ogawa strains of 2001/2002 with that in the V. cholerae O1 Inaba strains of the 1980s and 2001/2002. Isolates from the recent epidemic were shown to be related, irrespective of serotype, and had comparable banding patterns on PFGE, using NotI. They were distinctly different from those from the previous epidemic. Sequencing of the wbeT gene showed that the gene was highly conserved between the two epidemics. A single deletional mutation of an adenine residue was observed in the V. cholerae serotype Inaba isolates from the 2001/2002 epidemic, resulting in the serotype switch between the V. cholerae O1 strains from the recent epidemic. The distinct differences in PFGE patterns among isolates from the first and second epidemics exclude the possibility that the Inaba strain from the 1980s became dormant in the environment and mutated to serotype Ogawa, causing the 2001/2002 epidemic, despite the apparent consistency in the site of mutation in the Inaba serotypes between the two epidemics.

A Phase II study of the sterilising activities of ofloxacin, gatifloxacin and moxifloxacin in pulmonary tuberculosis

SETTING

Current treatment for pulmonary tuberculosis (TB) might be shortened by the incorporation of fluoroquinolones (FQs).

OBJECTIVES

A Phase II study aimed to assess the sterilising activities of three novel regimens containing FQs before a Phase III trial of a 4-month regimen containing gatifloxacin (GFX).

DESIGN

A total of 217 newly diagnosed smear-positive patients were randomly allocated to one of four regimens: isoniazid (INH), pyrazinamide and rifampicin (RMP) with either ethambutol, GFX, moxifloxacin (MFX) or ofloxacin (OFX) for 2 months. At the end of the study, RMP and INH were given for 4 months. The rates of elimination of Mycobacterium tuberculosis were compared in the regimens using non-linear mixed effects modelling of the serial sputum colony counts (SSCC) during the first 8 weeks.

RESULTS

After adjustment for covariates, MFX substitution appeared superior during the early phase of a bi-exponential fall in colony counts, but significant and similar acceleration of bacillary elimination during the late phase occurred with both GFX and MFX (P = 0.002). Substitution of OFX had no effect. These findings were supported by estimates of time to conversion, using Cox regression, but there were no significant differences in proportions culture-negative at 8 weeks.

CONCLUSIONS

GFX and MFX improve the sterilising activity of regimens and might shorten treatment; their progression into Phase III trials therefore seems warranted.

Bacterial contamination and over-dilution of commercial infant formula prepared by HIV-infected mothers in a Prevention of Mother-to-Child Transmission (PMTCT) Programme, South Africa

To examine the safety of formula feeds used by mothers participating in a Prevention of Mother-to-Child Transmission (PMTCT) programme, contents of 94 feeding bottles collected at a PMTCT-clinic were analysed. An additional 17 samples were taken from already prepared feeds during home visits, as well as 21 samples from bottles prepared under observation. Living conditions and educational levels were overall good and mothers had been counselled on safe formula preparation. Samples were analysed for faecal bacteria, using Escherichia coli and Enterococcus sp. as indicators. Protein concentration was used as an indicator of concentration of the formula. Out of 94, 63 (67%) of samples obtained at the clinic and 13/16 (81%) of available home samples were contaminated with faecal bacteria, compared to 8/21 (38%) of those prepared under observation. Out of 94, 58 (62%) of the clinic samples containing E. coli and 23/94 (24%) of those containing Enterococcus sp. were contaminated with more than the US government recommended limit of 10 CFU/ml. Out of 94, 26 (28%) of samples obtained at the clinic, 8/17 (47%) of home samples and 3/21 (14%) of those prepared under observation were over-diluted, compared to standards. Many mothers did not follow recommended practices in preparing and feeding the bottles.

High-risk sexual behaviour in men attending a sexually transmitted infection clinic in Durban, South Africa

OBJECTIVES

A study of men with genital ulcer disease (GUD) in Durban, South Africa, at the start of the local HIV epidemic in 1988/1989 found that 36% of men with GUD continued with sexual intercourse despite symptoms. The aim of this study was to determine whether this high-risk behaviour was still prevalent and to enquire about similar risk behaviours with other sexually transmitted infection (STI)-related problems.

METHODS

650 Men attending the main Durban STI clinic with a new complaint were enrolled. A standard questionnaire was administered. Polymerase chain reaction (PCR) tests were performed to diagnose genital herpes from ulcer specimens and gonorrhoea and chlamydia from those with urethral discharge and/or dysuria. Serology tests were performed for HIV, herpes simplex virus type 2 (HSV-2) and syphilis.

RESULTS

Sex since the start of symptoms was reported by between 33.3% and 43.9% of men with GUD, herpetic ulcers, gonorrhoea and/or chlamydia or dysuria. The incidence of condom use was very low in all groups having sex despite symptoms. In 87 men with genital ulcers confirmed positive for genital herpes by PCR testing, 30 (34.4%) had had sex since the start of symptoms, 28 (93.3%) of whom had had unprotected sex.

CONCLUSIONS

There is a high level of risk behaviour in this group of men in whom genital herpes is the most common cause of GUD. This risky sexual behaviour could reflect disinhibition, possibly because so many have already been infected with HSV-2, lack of education or other unknown factors. Syndromic STI management should be strengthened with intensive health education to promote community awareness of both genital ulceration and genital herpes and their role in facilitating HIV transmission. The low level of condom use indicates that condom promotion programmes still have much to achieve.

Opportunities for treating sexually transmitted infections and reducing HIV risk in rural South Africa

AIM

This paper is a report of a study to determine the aetiological distribution of sexually transmitted infections and prevalence of human immunodeficiency virus infection in selected primary health care clinic attendees.

BACKGROUND

South Africa has a high prevalence of human immunodeficiency virus and other sexually transmitted infections. Sexually transmitted infections are managed syndromically in the public sector as part of the essential nurse-driven primary care services provided at no cost to the client.

METHOD

This cross-sectional study was conducted in a rural community in South Africa between September and November 2002. A total of 277 consenting women were recruited. Vulvo-vaginal swabs were collected for screening for Neisseriae gonorrheae, Chlamydia trachomatis and Trichomonas vaginalis using DNA amplification methods and Gram stain with Nugent's score for the diagnosis of bacterial vaginosis. Seroprevalence of syphilis and human immunodeficiency virus infection were determined.

FINDINGS

The overall prevalence of human immunodeficiency virus in the study was 43.7% (95% confidence interval 37.6-50.0) with the prevalence in family planning clinic attendees 45.5% (95% confidence interval 38.9-52.3) and antenatal clinic attendees 33.3% (95% confidence interval 19.6-50.3). The prevalence of sexually transmitted infections amongst both the antenatal clinic and family planning attendees accounted for at least 70% of cases. Fifty per cent of women had one recognized sexually transmitted infection with 17.9% of the family planning and 14.5% of the antenatal clinic attendees having infections from two recognized pathogens. All infections were asymptomatic.

CONCLUSION

Nurse-driven antenatal and family planning services provide a useful opportunity for integrating reproductive health services, human immunodeficiency virus voluntary counselling and testing and treatment of sexually transmitted infections.

Effect of age, polymicrobial disease, and maternal HIV status on treatment response and cause of severe pneumonia in South African children: a prospective descriptive study

BACKGROUND

HIV-related pneumonia is the main cause of paediatric hospital admissions in southern Africa. We aimed to measure predictors of treatment failure and the cause of non-responsive pneumonia in children admitted to hospital with severe pneumonia in Durban, South Africa.

METHODS

We investigated 358 children aged 1-59 months who presented with WHO-defined severe or very severe pneumonia. Children were recruited irrespective of HIV status and started on a standard antimicrobial regimen of benzylpenicillin and gentamicin. All infants also received high-dose trimethoprim-sulfamethoxazole. The primary outcome measure was treatment failure at 48 h.

FINDINGS

242 (68%) children were HIV infected, 41 (12%) HIV exposed, uninfected, and 75 (21%) HIV uninfected. Failure to respond by 48 h was predicted by age under 1 year (adjusted odds ratio 6.38, 95% CI 2.72-14.91, p<0.0001), very severe disease (2.47, 1.17-5.24, p=0.0181), HIV status (HIV infected 10.3, 3.26-32.51; HIV exposed, uninfected 6.02, 1.55-23.38; p=0.0003), and polymicrobial disease (one organism 2.06, 1.05-4.05; two organisms 10.75, 4.38-26.36; p<0.0001) on logistic regression analysis. All children with three organisms failed treatment. 72/110 treatment failures had at least two organisms isolated. Three of nine HIV-exposed, uninfected infants, 29/74 HIV-infected, but no HIV-uninfected infants who failed study therapy had Pneumocystis jirovecii pneumonia.

INTERPRETATION

For children younger than 1 year, the WHO guidelines are inadequate and need to be revised since both HIV-infected and HIV-exposed, uninfected infants had more treatment failures than did HIV-uninfected infants. Polymicrobial disease is an important reason for treatment failure, and we need to identify rapid low-cost diagnostic methods to assist clinicians.

The catalase reaction of Shigella species and its use in rapid screening for epidemic Shigella dysenteriae type 1

As epidemic dysentery caused by Shigella dysenteriae type 1 is associated with high mortality, early identification of outbreaks is important. Since S. dysenteriae type 1 differs from most of the Enterobacteriaceae in that it does not produce catalase, a test for catalase may provide a useful screening method. The ability of a catalase test to provide rapid identification of S. dysenteriae type 1 has now been assessed, using isolates of this pathogen from five continents, Shigella of other species, and entero-invasive (EIEC) and Shiga-toxin-producing Escherichia coli (STEC). All of the isolates of S. dysenteriae type 1, as well as S. dysenteriae of types 3, 4, 6, 9, 11 and 12 and S. boydii of type 12, were found catalase-negative. All the other bacteria tested were positive for catalase. In an epidemic setting in South Africa, 406 xylose-negative and lysine-decarboxylase-negative isolates, collected from xylose-lysine-deoxycholate (XLD) agar, were tested for catalase. All 356 of the catalase-negative isolates were confirmed to be of S. dysenteriae type 1. None of the catalase-positive isolates were of S. dysenteriae type 1. The catalase test is useful in the rapid, presumptive identification of S. dysenteriae type 1, from appropriate culture media, because of its high predictive value, simplicity and speed. It would be particularly useful during dysentery outbreaks, when other Shigella would be uncommon. There was no association between the absence of catalase activity and the production of Shiga toxin.

Bacterial safety of flash-heated and unheated expressed breastmilk during storage

Heat-treated breastmilk is one infant-feeding option recommended by the WHO to reduce mother-to-child transmission of HIV in developing countries. Flash-heat, a simple pasteurization method that a mother could perform in her home, has been shown to inactivate cell-free HIV-1. Since heating may affect the naturally occurring antimicrobial properties found in breastmilk, storing heated breastmilk may present a safety issue in resource-poor settings due to lack of refrigeration and potential contamination. To address this, we investigated the ability of flash-heat to eliminate bacteria and to prevent growth over time compared with unheated breastmilk. We collected breastmilk samples from 38 HIV positive mothers in South Africa and aliquoted them to flash-heated and unheated controls. Samples were stored at room temperature for 0, 2, 6 and 8 h and then plated and incubated for 24 h at 37 degrees C in CO(2). We performed total colony counts and identified Escherichia coli, Staphylocuccus aureus and Group A and Group B streptococci. Unheated samples had a significantly higher number of samples positive for bacterial growth at each time point (p < 0.0001), as well as mean colony-forming units (CFU)/ml in those samples that were positive at each time point (p < 0.0001). In addition, unheated samples had a significantly higher rate of bacterial propagation over time than flash-heated samples when comparing log values of CFU/ml across 0-8 h (p < 0.005). No pathogenic growth was observed in the flash-heated samples, while the unheated samples showed growth of E. coli (n = 1) and S. aureus (n = 6). Our data suggest that storage of flash-heated breastmilk is safe at room temperature for up to 8 h.

A multi-centre evaluation of nine rapid, point-of-care syphilis tests using archived sera

OBJECTIVES

To evaluate nine rapid syphilis tests at eight geographically diverse laboratory sites for their performance and operational characteristics.

METHODS

Tests were compared "head to head" using locally assembled panels of 100 archived (50 positive and 50 negative) sera at each site using as reference standards the Treponema pallidum haemagglutination or the T pallidum particle agglutination test. In addition inter-site variation, result stability, test reproducibility and test operational characteristics were assessed.

RESULTS

All nine tests gave good performance relative to the reference standard with sensitivities ranging from 84.5-97.7% and specificities from 84.5-98%. Result stability was variable if result reading was delayed past the recommended period. All the tests were found to be easy to use, especially the lateral flow tests.

CONCLUSIONS

All the tests evaluated have acceptable performance characteristics and could make an impact on the control of syphilis. Tests that can use whole blood and do not require refrigeration were selected for further evaluation in field settings.

Extensively drug-resistant tuberculosis as a cause of death in patients co-infected with tuberculosis and HIV in a rural area of South Africa

BACKGROUND

The epidemics of HIV-1 and tuberculosis in South Africa are closely related. High mortality rates in co-infected patients have improved with antiretroviral therapy, but drug-resistant tuberculosis has emerged as a major cause of death. We assessed the prevalence and consequences of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis in a rural area in KwaZulu Natal, South Africa.

METHODS

We undertook enhanced surveillance for drug-resistant tuberculosis with sputum culture and drug susceptibility testing in patients with known or suspected tuberculosis. Genotyping was done for isolates resistant to first-line and second-line drugs.

RESULTS

From January, 2005, to March, 2006, sputum was obtained from 1539 patients. We detected MDR tuberculosis in 221 patients, of whom 53 had XDR tuberculosis. Prevalence among 475 patients with culture-confirmed tuberculosis was 39% (185 patients) for MDR and 6% (30) for XDR tuberculosis. Only 55% (26 of 47) of patients with XDR tuberculosis had never been previously treated for tuberculosis; 67% (28 of 42) had a recent hospital admission. All 44 patients with XDR tuberculosis who were tested for HIV were co-infected. 52 of 53 patients with XDR tuberculosis died, with median survival of 16 days from time of diagnosis (IQR 6-37) among the 42 patients with confirmed dates of death. Genotyping of isolates showed that 39 of 46 (85%, 95% CI 74-95) patients with XDR tuberculosis had similar strains.

CONCLUSIONS

MDR tuberculosis is more prevalent than previously realised in this setting. XDR tuberculosis has been transmitted to HIV co-infected patients and is associated with high mortality. These observations warrant urgent intervention and threaten the success of treatment programmes for tuberculosis and HIV.

Association Between HIV and Subpreputial Penile Wetness in Uncircumcised Men in South Africa

OBJECTIVES

To describe the prevalence and characteristics of subpreputial penile wetness and to investigate the association between current levels of penile wetness and HIV infection.

METHODS

Male attenders at a sexually transmitted infections clinic in Durban, South Africa were enrolled and treated for their presenting sexually transmitted infection complaint. They were asked to return after 14 days when a structured questionnaire was administered, and the degree of wetness of the glans penis and coronal sulcus was assessed clinically.

RESULTS

Six hundred and fifty men were enrolled, and 488 (75%) returned. Three hundred eighty-six uncircumcised men were included for statistical analysis of whom 215 (56%) were HIV positive. One hundred ninety-six (50.8%) had no penile wetness, and 190 (49.2%) had penile wetness. In the adjusted analysis, penile wetness was associated with younger age, low level of attained education, low income, higher lifetime numbers of sexual partners, and not washing after sex. The prevalence of HIV was greater in those with penile wetness 126 of 190 (66.3%) compared with 90 of 196 (45.9%) with no penile wetness, crude prevalence odds ratio 2.32 (95% confidence interval [CI], 1.54-3.50, P=or<0.001), crude prevalence relative risk 1.44 (95% CI, 1.23-1.63, P=or<0.001), and adjusted for predictors of HIV, confounders and herpes type 2 antibodies, odds ratio 2.38 (95% CI, 1.42-3.97, P=or<0.001), and relative risk 1.46 (95% CI, 1.19-1.68, P=or<0.001).

CONCLUSIONS

This is the first study to show an association between subpreputial penile wetness and HIV. Consideration should be given to providing advice about improving penile hygiene in uncircumcised men in areas where HIV is a significant problem. Good penile hygiene should also be promoted at the community level to become a desirable social norm.

CTX-M-37 in Salmonella enterica serotype Isangi from Durban, South Africa

Beta-lactamase-mediated resistance was investigated in 59 putative extended-spectrum beta-lactamase (ESBL)-positive Salmonella spp. from the paediatric ward of a tertiary hospital in Durban, South Africa. Three Salmonella enterica serotype Isangi cultured from stool samples were multidrug resistant, with susceptibility only to meropenem, piperacillin/tazobactam and cefoxitin. Isoelectric focusing revealed beta-lactamases with isoelectric points of pI 5.8, 6.8 and 7.2. Sequencing identified beta-lactamases CTX-M-37 and TEM-1. To our knowledge, this is the first report of CTX-M-37 from S. enterica serotype Isangi in South Africa.

Lack of Association between the Nasopharyngeal Carriage ofStreptococcuspneumoniaeandStaphylococcusaureusin HIV‐1–Infected South African Children

We investigated the nasopharyngeal carriage of Streptococcus pneumoniae and Staphylococcus aureus in 355 children hospitalized with severe pneumonia. Of the children, 239 (67.3%) were human immunodeficiency virus (HIV)-1 positive; 169 (47.6%) carried S. pneumoniae, 91 (25.6%) carried S. aureus, and 33 (9.3%) carried both. S. pneumoniae carriage was not related to HIV-1 status. The HIV-1-positive children had a significantly higher rate of S. aureus carriage than did the HIV-1-negative children (31.4% vs. 13.8%; P<.001). The rate of S. aureus carriage in the HIV-1-negative S. pneumoniae carriers was significantly lower than that in the noncarriers (5.5% vs. 21.3%; P=.013), but the rate of S. aureus carriage in the HIV-1-positive S. pneumoniae carriers was not significantly lower than that in the noncarriers (26.3% vs. 36.0%; P=.11). We did not find a negative association between S. pneumoniae and S. aureus carriage in HIV-1-positive hospitalized children with severe pneumonia.

Molecular epidemiology of recently emergent ciprofloxacin-resistant Neisseria gonorrhoeae in South Africa

OBJECTIVES

Syndromic management guidelines for male urethritis syndrome and female discharge syndrome (nonpregnant) in South Africa advocate the use of ciprofloxacin for potential infection with Neisseria gonorrhoeae. In 2003, reports of clinical failure of gonorrhea following ciprofloxacin treatment prompted a clinic-based surveillance to detect the presence of resistant isolates.

STUDY

Urethral samples for the isolation of N gonorrhoeae were obtained from consecutive male patients with urethral discharge attending the largest sexually transmitted disease clinic in KwaZuluNatal. Molecular typing of isolates was performed by means of N gonorrhoeae multiantigen sequence typing (NG-MAST).

RESULTS

Of 139 isolates, 31 (22%) were resistant to ciprofloxacin (minimum inhibitory concentration >or=1 mg/l). NG-MAST revealed novel, as well as previously described, sequence types (ST). The largest cluster of our isolates belonged to ST 217. This ST has been reported among ciprofloxacin-resistant isolates from Europe.

CONCLUSION

: The results underscore the urgency of review of the current treatment guidelines for discharge disease in KwaZuluNatal.

Genotyping Trichomonas vaginalis

A genotyping method has been developed to distinguish each Trichomonas vaginalis isolate and has provided the first genome mapping studies of this protist with an estimated 180Mb genome. The technique was developed using high molecular weight DNA prepared from five laboratory isolates from Australia and USA and 20 clinical isolates from South Africa. Inhibition of the notorious T. vaginalis endogenous nucleases by addition of potent inhibitors was essential to the success of this study. Chromosomal DNA larger than 2.2Mb was macrorestricted to a minimum segment size of approximately 50kb, separated by pulsed field gel electrophoresis and hybridised with a variety of gene probes. Each isolate generated a unique pattern that was distinguished by each of the probes. Four single copy gene probes (fd, hmp35, ibp39 and pfoD) were identified but probes which identified several bands (pfoB and alpha-scs) per isolate were most informative for genotyping. The pyruvate:ferredoxin oxidoreductase B gene probe identified two to seven copies of pfoB (or its closely related homologue pfoA) per genome in different isolates and is an obvious candidate probe to identify epidemiological linkage between infections by this genotyping method. Cleavage of the genomes into smaller fragments failed to distinguish isolates from diverse locations indicating the proximal regions of genes are conserved.

Antibiotic use and resistance in public-sector hospitals in KwaZulu-Natal

OBJECTIVE

To investigate a possible association between level of care, antibiotic use and antimicrobial resistance in 16 public-sector hospitals providing different levels of care in KwaZulu-Natal.

DESIGN

A multicentre surveillance study was undertaken in 16 hospitals at three progressive levels of health care (district, regional, tertiary) where each hospital submitted 100 consecutive, non-repetitive isolates judged in the laboratory to be of potential clinical significance. Isolates were identified and susceptibility testing was undertaken using the Kirby-Bauer disc diffusion method with minimum inhibitory concentrations (MICs) extrapolated on an automated reading system. Isolates were grouped according to their natural resistance profiles, and percentage susceptibility, mean percentage susceptibility and standard deviation to each antibiotic were stratified within and across hospital levels. Antibiotic use data were expressed as the number of daily divided doses (DDDs) per 1000 patient-days.

SETTING

Two tertiary, 9 regional and 5 district public hospitals in KwaZulu-Natal.

OUTCOME MEASURES

Percentage susceptibility.

RESULTS

There was a general trend among the 1 270 isolates of highest susceptibility in district hospitals, followed by regional and then tertiary hospitals. This is consistent with the referral system where health conditions become increasingly severe/complex requiring greater antibiotic use and broader-spectrum agents at progressive hospital levels, with statistical significance (p < 0.05) evident where sample numbers were relatively large. Trend variations could be associated with the qualitative and quantitative differences in antibiotic use, albeit without statistical corroboration. Three per cent of the total number of isolates were sensitive to all antibiotics tested and 6% were resistant to a single agent only. The remaining 91% showed acquired resistance to more than one drug. The standard deviation ranged from 0% to 55%.

CONCLUSIONS

This study showed that resistance profiles among bacteria varied greatly within and across hospital levels. While antibiotic use varied as much, a statistically significant correlation between use and resistance could not be established. It was therefore postulated that the effect of selection pressure was obscured by other resistance determinants apparent in public hospitals in resource-poor settings. On a clinical level, the study showed that resistance profiles among bacteria vary too much to allow a national antibiotic policy as proposed in the standard treatment guidelines. Rather, such guidelines should be directed to specific profiles found in different hospitals and at different levels of health care. Regular surveillance to adjust such guidelines is essential.

Intravenous glucose preparation as the source of an outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae infections in the neonatal unit of a regional hospital in KwaZulu-Natal

In the last week of May 2005, staff at Mahatma Gandhi Memorial Hospital in KwaZulu-Natal realised that many babies in the high-care nursery ward had bloodstream infections involving Klebsiella pneumoniae bacteria. Attempts to identify a common source of infection failed. The ward was therefore closed and new babies needing high care were admitted to another empty ward. Despite this, babies still became infected. This resulted in a request for assistance from the Department of Medical Microbiology of the Nelson R Mandela School of Medicine. A search for common factors through case history studies of the 26 infected babies showed that blood cultures of the babies remained positive despite the administration of appropriate antibiotics. Different options that could explain this were investigated. The organism was found in intravenous glucose preparations used for multiple dosing. Unopened vials of the same medication were sterile. The nursery was found to lack proper hand-wash facilities and to be overcrowded and understaffed. Reinforcement of hand hygiene and a ban on the multiple dosing of medicines stopped the outbreak. In conclusion, this outbreak resulted from a combination of factors among which lack of hand hygiene and multiple dosing of an intravenous glucose preparation were most significant.

Molecular diagnosis of lymphogranuloma venereum in patients with genital ulcer disease

The detection of herpes, chancroid, and syphilis in genital ulcers is done by PCR. This is not so for lymphogranuloma venereum (LGV). We report on the use of a PCR with digestion that differentiates the LGV biovar from the trachoma biovar. Our findings suggest that the clinical description of LGV in current textbooks is incomplete.

Risk factors of sexually transmitted infections among migrant and non-migrant sexual partnerships from rural South Africa

In October 1998, cohorts of circular migrant men and their non-migrant sexual partners, and non-migrant men and their non-migrant sexual partners from rural South Africa were recruited and followed-up every 4 months until October 2001. At each visit, information on sociodemographic, sexual behaviour, sexually transmitted infections (STIs) and HIV was collected. In total, 553 individuals aged between 18 and 69 years were recruited. A man and his sexual partner(s) form a sexual partnership. Migration status, age, marital status, age at sexual debut, recent sexual partners and HIV status were found to be important determinants of STI. The risk of STI varies (sigma2 = 1.45, P < 0.001) significantly across sexual partnerships even after controlling for important determinants. The variance implies substantial correlation (0.59) between members of the same sexual partnership. Ignoring this correlation leads to incorrect inference. Migration contributes significantly to the spread of STIs. Community interventions of HIV/STI should target co-transmitter sexual partnerships rather than high-risk individuals.

Management of vaginal discharge syndrome: how effective is our strategy?

Although syndromic management of sexually transmitted diseases in highly endemic areas provides a short-term benefit to the individuals treated, it has no impact on decreasing prevalence rates. The numerous factors that contribute to this are discussed. Rapid reinfection from a large pool of infected symptomatic and asymptomatic individuals as well as the non-specific nature of presenting symptoms in women with vaginal discharge syndrome are major causes.