Molecular characterization of streptococcus agalactiae isolated from pregnant women in the Eastern Cape, South Africa and Windhoek, Namibia and antibacterial activities of some medicinal plant extracts on the isolates

Streptococcus agalactiae (S. agalactiae) also known as group B Streptococcus (GBS) is one of the leading causes of bacterial morbidity and mortality among neonates worldwide. It is the cause of invasive Early Onset Disease (EOD), which occurs in the first 7 days of life and characterised by sepsis, pneumonia and meningitis and Late Onset Disease (LOD) occurring between 7 and 89 days of life. Late onset disease is characterised by meningitis and long term neurological sequelae such as cerebral palsy, hearing impairment and cognitive challenges. S. agalactiae does not only infect neonates, it also infects the elderly, immunocompromised individuals and pregnant and non-pregnant women, causing invasive disease. In the world, 10-40 percent of healthy women are rectally or vaginally colonised with GBS and they face the risk of passing it to their babies during the process of childbirth. During parturition, a GBS colonized pregnant woman transfers the bacterium to her new-born as the baby passes through the ruptured membrane, thus infecting the child. However, GBS has been reported to be transferred even without rupture of membranes. Once it infects the membranes, it is transferred into the amniotic fluid and subsequently infects the baby. It can be aspirated into the lungs causing pneumonia or it can infect the blood stream and disseminated round the body causing septicaemia, meningitis and other infections. Once in the neonate’s body, the bacteria is able to evade the immune system as the host immune system is not yet fully developed. Bacterial evasion of the immune system is enhanced by its various virulence factors which are deployed to help it escape the immune system. These include the polysaccharide capsule, haemolysin and the release of complement inactivating factors such C5a peptidase. The World Health Organisation (WHO) (2010) recommends universal screening of pregnant women to identify those colonised and who are at risk of passing the bacterium to their babies during birth. WHO also recommends identification of at risk women and providing Intrapartum Antibiotic Prophylaxis (IAP) using penicillin. However, problems arise in penicillin allergic women and while alternatives for IAP include erythromycin and clindamycin, there is increasing resistance to these drugs thereby limiting therapeutic options. Antimicrobial susceptibility testing is also not always possible in most resource constrained countries due to poor infrastructure, limited access to health care and the logistical problems in implementing the WHO guidelines. Alternative therapeutic options to GBS infection include developing new and potent antibiotics, development of a vaccine, use of medicinal plants and the use of bacteriophage therapy. While these look like better alternatives there is massive scientific work to be carried out to ensure proper characterisation and efficiency of such alternatives. This process should be followed by in vitro diagnostic testing, experiments with animal models and clinical trials. The problems encountered during vaccine development to curtail GBS infection are compounded by the multiplicity of S. agalactiae capsular types which vary in different geographic locations. Medicinal plants are a cheap and convenient option since they are widely used in communities but the phytochemical components of the plants have to be identified and subjected to in vitro testing to evaluate their therapeutic efficacy as antimicrobial agents. This study therefore sought to isolate GBS from pregnant women between 35 and 37 weeks gestation in Windhoek (Namibia) and the Eastern Cape (South Africa), to determine the prevalence of GBS colonisation in the vagina and rectum of the pregnant women, characterise the isolates by molecular techniques, determine the antimicrobial resistance profiles and genes of the isolates and explore the efficacies of medicinal plant extracts as possible candidates for therapeutic options

Genexpert MTB/RIF diagnostic and tuberculosis treatment initiation delays in Namibia

BACKGROUND : Early diagnosis and treatment of drug resistant tuberculosis are crucial in the control of the disease and treatment success. In Namibia, there is a gap in empirical data on the diagnosis and treatment initiation delay time since the roll-out of the GeneXpert MTB/RIF (Xpert) assay in 2017. This study aimed to determine Xpert pre-diagnosis and turnaround time at Namibian Institute of Pathology (NIP) as well as rifampicin resistant tuberculosis (RR-TB) treatment initiation delay on patients admitted at Katutura Intermediate Hospital TB clinic. METHODS : This was retrospective descriptive cross-sectional study which was conducted from 1 July 2018 to 31 March 2019. A total of seventy two participants comprising of twenty five RR-TB and forty seven non RR-TB patients were enrolled using consecutive sampling method. Laboratory information system (LIS) was utilized to determine Xpert median pre-analytical delay and turnaround time. Patients’ records and LIS were used to calculate median treatment initiation delay time post Xpert diagnosis. Data on continuous variables was summarized as median and interquartile range. RESULTS : The median pre-diagnostic, diagnostic and treatment initiation delay time were 7.5 (IQR: 0-14), 1 (IQR: 0-3) and 10 (IQR: 1-32) days respectively for RR-TB. For drug susceptible TB, the median pre-diagnostic, diagnostic and treatment initiation delay time were 5 (IQR: 1-8), 1 (IQR: 0-3) and 3 (IQR: 0-12) days respectively. Overall, median health system delay time was 21 (IQR: 2-32) days for RR-TB patients and 12 (IQR: 1-12) days for non RR-TB patients. CONCLUSION : Treatment initiation to appropriate second line regimes was long for many patients and may be attributable to poor interpretation of discordant results and increased number of RR-TB patients for treatment since Xpert adoption. Unnecessary referrals due to shortages of pulmonologists, cumbersome baseline investigations and outdated guidelines and policies could be the determinants of health system delay time. Interventions targeted at addressing identified factors should be implemented. Further studies should explore the actual treatment gap among RR-TB patients and further risk factors for delayed treatment.https://www.wjahr.comam2020School of Health Systems and Public Health (SHSPH

The effect of underlying inflammation on iron metabolism, cardiovascular risk and renal function in patients with type 2 diabetes

Abstract Aim To investigate the impact of inflammation on iron metabolism, cardiovascular risk and renal function in type 2 diabetes (T2D). Methods A total of 50 patients with T2D were included in this study. The patients were stratified into two groups based on their levels of C‐reactive protein (CRP), namely normal and high levels (n = 25/group). All laboratory tests were measured using standardised methods. Results Fasting plasma glucose levels were elevated in patients with high CRP when compared to those with normal levels (p = 0.0413). Total serum iron levels were lower in patients with high CRP levels (12.78 ± 3.50) when compared to those with normal levels (15.26 ± 4.64), p = 0.0381. However, ferritin and transferrin levels were comparable between the groups (p > 0.05). The mean cell volume (MCV) in the high CRP group was lower (87.66 ± 3.62) than the normal level group (90.79 ± 4.52), p = 0.0096, whilst the lipograms were similar (p > 0.05). The estimated glomerular filtration rate (eGFR) was lower in the high CRP group (98.06 ± 11.64) than the normal level group (104.7 ± 11.11), p = 0.046. Notably, CRP levels were negatively associated with serum iron levels (r = –0.38, p = 0.0061), MCV (r = –0.41, p = 0.0031), potassium (r = –0.37, p = 0.0086) and sodium levels (r = –0.28, p = 0.0471). Regression analyses showed that only CRP (β = –0.16, standard error [SE]: 0.06, p = 0.0125) and sodium (β = 0.51, SE: 0.25, p = 0.0434) levels contributed significantly to the prediction of serum iron levels. Conclusion Underlying inflammation in T2D is associated with increased incidence of hypertension and reduced levels of serum iron, MCV and renal function. Although there was no apparent clinical anaemia or renal dysfunction in these patients, mitigating inflammation may be effective in circumventing the ultimate development of iron deficiency anaemia and chronic kidney disease in T2D

Prevalence and capsular type distribution of Streptococcus agalactiae isolated from pregnant women in Namibia and South Africa

Abstract Background Streptococcus agalactiae or Group B Streptococcus (GBS) is the leading cause of neonatal morbidity and mortality resulting in septicaemia, bacteraemia and meningitis. Long term problems in children range from loss of hearing to mental retardation. While Intrapartum Antibiotic Prophylaxis (IAP) has reduced the incidence of S. agalactiae infection, it still remains the leading cause of disease in neonates. GBS has ten capsular types whose distribution varies across the world. Therefore, this study sought to determine the prevalence of GBS in Namibia and South Africa amongst pregnant women between 35 and 37 weeks gestation and elucidate the capsular types. Methods Lower vaginal and rectal swabs were collected from pregnant women between 35 and 37 weeks gestation. Five hundred and thirty pregnant women were recruited into the study in Windhoek, Namibia while one hundred pregnant women were recruited in the Eastern Cape, South Africa. The swabs were cultured on 5% sheep blood agar (Biomerieux, New Jersey, USA) for isolation of GBS. Presumptive isolates were confirmed using both the Vitek (2) and molecular techniques targeting the scpB gene. Capsular typing was performed in a multiplex PCR with capsular specific primer pairs. Results The prevalence of GBS in Namibia was 13.6 and 37% in South Africa respectively. In both countries most women were dually colonised with GBS. Capsular types II, III and V were the most prevalent. Conclusions The prevalence of GBS in Namibia was lower than in South Africa in this study. The prevalence in both countries was not different from those reported in other African countries and around the world. The predominant capsular types in this study are the ones commonly associated with adverse maternal outcomes