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1.
S Afr Med J ; 111(3): 260-264, 2021 Mar 02.
Article in English | MEDLINE | ID: mdl-33944749

ABSTRACT

BACKGROUND: An increasing number of girls living with perinatally acquired HIV (PHIV) are reaching adolescence and adulthood and becoming pregnant. Youth living with PHIV (YLPHIV) may have HIV-associated infections/complications, long-term exposure to antiretroviral treatment (ART), drug resistance and increased psychosocial challenges, which may adversely affect pregnancy outcomes. There is a lack of published studies on pregnancy in YLPHIV in sub-Saharan Africa. Objectives. To describe characteristics of pregnant South African (SA) YLPHIV and their pregnancy outcomes. METHODS: We retrospectively identified pregnancies in YLPHIV, who were diagnosed with HIV when they were <12 years old and before their first pregnancy (as a proxy for perinatal route of infection), from routinely collected data in Western Cape Province, SA (2007 - 2018). We combined these with pregnancies from a Johannesburg cohort of YLPHIV. Results. We identified 258 pregnancies among 232 females living with likely PHIV; 38.8% of pregnancies occurred in YLPHIV ≤16 years old, 39.1% at age 17 - 19 years and 22.1% at age ≥20 years. In recent years, a steady increase in the number of pregnancies in YLPHIV was noted; more than two-thirds occurred during 2016 - 2018. ART was commenced prior to pregnancy in 84.9% of YLPHIV, during pregnancy in 6.6% and was not commenced by pregnancy end date in 8.5%. Of the pregnancies in young women with documented outcomes (88.8%; n=229), 80.3% were live births, 14.4% terminations, 3.1% miscarriages and 2.2% stillbirths. Mother-to-child transmission of HIV occurred in 2.2% of infants, 75.3% were uninfected when last tested and 22.6% had unknown HIV status. Among YLPHIV with CD4 counts available within 12 months of pregnancy end date (n=202), 20.3% had a CD4 count <200 cells/µL, 43.1% CD4 count 200 - 499 cells/µL and 36.6% CD4 count ≥500 cells/µL. Among those with a viral load (VL) available within 12 months of pregnancy end date (n=219), 66.7% had a VL <400 copies/mL, 5.0% VL 400 - 999 copies/mL and 28.3% VL ≥1 000 copies/mL. Of 186 neonates, 20.4% were preterm deliveries (<37 weeks' gestation). Among neonates with known birthweight (n=176), the mean birthweight was 2 900 g (95% confidence interval (CI) 2 747 - 2 935 g) and 20.5% had a low birthweight (<2 500 g). One congenital malformation (musculoskeletal) and 2 neonatal deaths were recorded. CONCLUSIONS: In recent years, the number of pregnancies in YLPHIV has increased. A considerable proportion of pregnancies occurred in YLPHIV ≤16 years old. A high proportion of pregnancies was electively terminated. The prevalence of elevated VL and poor immunological status among pregnant YLPHIV is concerning.


Subject(s)
HIV Infections/epidemiology , HIV Infections/transmission , Infectious Disease Transmission, Vertical , Pregnancy Complications, Infectious/epidemiology , Pregnancy in Adolescence , Adolescent , Adult , Anti-Retroviral Agents/therapeutic use , CD4 Lymphocyte Count , Child , Female , HIV Infections/drug therapy , Humans , Pregnancy , Pregnancy Outcome , South Africa/epidemiology , Viral Load
2.
S Afr Med J ; 110(10): 1050-1055, 2020 Sep 30.
Article in English | MEDLINE | ID: mdl-33205738

ABSTRACT

BACKGROUND: Young South Africans experience high rates of HIV infection. While nationally scaled medical male circumcision (MMC) can help to curb HIV infection rates in countries such as South Africa (SA), MMC uptake has not been consistent or universal, suggesting variable acceptability among men. Both MMC and traditional male circumcision (TMC) are practised in SA. For male circumcision to be most effective for HIV prevention, it should be performed prior to sexual debut with complete removal of the foreskin. OBJECTIVES: The MACHO (Male Adolescent Choices for HIV Prevention Options) study investigated uptake of and preference for MMC v. TMC in two culturally distinct settings in SA. METHODS: This observational, longitudinal, cohort study investigated circumcision preferences and uptake in 100 males (aged 14 - 17 years) and their legal guardians in Cape Town (Western Cape Province) and Soweto (Gauteng Province). Data were collected via surveys administered every 4 months over a 24-month period. RESULTS: A total of 100 uncircumcised adolescent boys (Cape Town n=50, Soweto n=50; mean (interquartile range) age 15 (14 - 16) years) and their guardians were enrolled. At baseline, 42 boys from Soweto (84%) and none from Cape Town expressed a preference for MMC over TMC. Sowetan participants were more likely to elect circumcision (MMC n=11 (22%), TMC n=1 (2%)) than those from Cape Town (TMC n=1 (2%), MMC n=0) over 13.6 months of follow-up (hazard ratio 18.9; 95% confidence interval 2.37 - 150.71; p=0.006). CONCLUSIONS: MMC was the preferred option for young men in Soweto compared with those in Cape Town, and this translated into practice. Despite knowledge of the benefits of early MMC, many participants delayed uptake, potentially reducing the MMC benefits before sexual debut. Programmes promoting circumcision should consider the influence of local practices. To realise full HIV prevention benefits, efforts should be made to ensure that circumcision is promoted, and that all circumcision is safe, performed prior to sexual debut, and contextually responsive.


Subject(s)
Circumcision, Male/ethnology , Circumcision, Male/statistics & numerical data , HIV Infections/prevention & control , Patient Acceptance of Health Care/ethnology , Patient Acceptance of Health Care/statistics & numerical data , Adolescent , Culture , Facilities and Services Utilization , Health Knowledge, Attitudes, Practice , Humans , Kaplan-Meier Estimate , Longitudinal Studies , Male , Motivation , Procedures and Techniques Utilization , Proportional Hazards Models , Sexual Behavior , Sexually Transmitted Diseases/prevention & control , South Africa/epidemiology
3.
Epidemiol Infect ; 146(8): 1036-1042, 2018 06.
Article in English | MEDLINE | ID: mdl-29708084

ABSTRACT

Respondent-driven sampling (RDS) is widely used to estimate HIV prevalence in men who have sex with men (MSM). Mathematical models that are calibrated to these data may be compromised if they fail to account for selection biases in RDS surveys. To quantify the potential extent of this bias, an agent-based model of HIV in South Africa was calibrated to HIV prevalence and sexual behaviour data from South African studies of MSM, first reweighting the modelled MSM population to match the younger age profile of the RDS surveys (age-adjusted analysis) and then without reweighting (unadjusted analysis). The model estimated a median HIV prevalence in South African MSM in 2015 of 34.6% (inter-quartile range (IQR): 31.4-37.2%) in the age-adjusted analysis, compared with 26.1% (IQR: 24.1-28.4%) in the unadjusted analysis. The median lifetime risk of acquiring HIV in exclusively homosexual men was 88% (IQR: 82-92%) in the age-adjusted analysis, compared with 76% (IQR: 64-85%) in the unadjusted analysis. These results suggest that RDS studies may under-estimate the exceptionally high HIV prevalence rates in South African MSM because of over-sampling of younger MSM. Mathematical models that are calibrated to these data need to control for likely over-sampling of younger MSM.


Subject(s)
HIV Infections/epidemiology , Homosexuality, Male/statistics & numerical data , Adolescent , Adult , Bias , Humans , Male , Middle Aged , Models, Theoretical , Prevalence , Sampling Studies , South Africa/epidemiology , Young Adult
4.
Epidemiol Infect ; 139(12): 1875-83, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21299913

ABSTRACT

Most mathematical models of sexually transmitted infections (STIs) assume that infected individuals become susceptible to re-infection immediately after recovery. This paper assesses whether extending the standard model to allow for temporary immunity after recovery improves the correspondence between observed and modelled levels of STI prevalence in South Africa, for gonorrhoea, chlamydial infection and trichomoniasis. Five different models of immunity and symptom resolution were defined, and each model fitted to South African STI prevalence data. The models were compared in terms of Bayes factors, which show that in the case of gonorrhoea and chlamydial infection, models that allow for immunity provide a significantly better fit to STI prevalence data than models that do not allow for immunity. For all three STIs, estimates of the impact of changes in STI treatment and sexual behaviour are significantly lower in models that allow for immunity. Mathematical models that do not allow for immunity could therefore overestimate the effectiveness of STI interventions.


Subject(s)
Chlamydia Infections/immunology , Gonorrhea/immunology , Models, Biological , Trichomonas Infections/immunology , Adolescent , Adult , Bayes Theorem , Chlamydia Infections/epidemiology , Female , Gonorrhea/epidemiology , Humans , Immunity, Active , Middle Aged , Models, Immunological , Prevalence , South Africa/epidemiology , Trichomonas Infections/epidemiology , Young Adult
6.
Clin Infect Dis ; 48(1): 108-14, 2009 Jan 01.
Article in English | MEDLINE | ID: mdl-19049436

ABSTRACT

BACKGROUND: There are limited population-based estimates of tuberculosis incidence among human immunodeficiency virus (HIV)-infected and HIV-uninfected infants aged < or =12 months. We aimed to estimate the population-based incidence of culture-confirmed tuberculosis among HIV-infected and HIV-uninfected infants in the Western Cape Province, South Africa. METHODS: The incidences of pulmonary, extrapulmonary, and disseminated tuberculosis were estimated over a 3-year period (2004-2006) with use of prospective representative hospital surveillance data of the annual number of culture-confirmed tuberculosis cases among infants. The total number of HIV-infected and HIV-uninfected infants was calculated using population-based estimates of the total number of live infants and the annual maternal HIV prevalence and vertical HIV transmission rates. RESULTS: There were 245 infants with culture-confirmed tuberculosis. The overall incidences of tuberculosis were 1596 cases per 100,000 population among HIV-infected infants (95% confidence interval [CI], 1151-2132 cases per 100,000 population) and 65.9 cases per 100,000 population among HIV-uninfected infants (95% CI, 56-75 cases per 100,000 population). The relative risk of culture-confirmed tuberculosis among HIV-infected infants was 24.2 (95% CI, 17-34). The incidences of disseminated tuberculosis were 240.9 cases per 100,000 population (95% CI, 89-433 cases per 100,000 population) among HIV-infected infants and 14.1 cases per 100,000 population (95% CI, 10-18 cases per 100,000 population) among HIV-uninfected infants (relative risk, 17.1; 95% CI, 6-34). CONCLUSIONS: This study indicates the magnitude of the tuberculosis disease burden among HIV-infected infants and provides population-based comparative incidence rates of tuberculosis among HIV-infected infants. This high risk of tuberculosis among HIV-infected infants is of great concern and may be attributable to an increased risk of tuberculosis exposure, increased immune-mediated tuberculosis susceptibility, and/or possible limited protective effect of bacille Calmette-Guérin vaccination. Improved tuberculosis control strategies, including maternal tuberculosis screening, contact tracing of tuberculosis-exposed infants coupled with preventive chemotherapy, and effective vaccine strategies, are needed for infants in settings where HIV infection and tuberculosis are highly endemic.


Subject(s)
HIV Infections/complications , Tuberculosis/epidemiology , Humans , Incidence , Infant , Infant, Newborn , Mycobacterium tuberculosis/isolation & purification , South Africa/epidemiology
7.
Aliment Pharmacol Ther ; 27(4): 327-37, 2008 Feb 15.
Article in English | MEDLINE | ID: mdl-18005248

ABSTRACT

BACKGROUND: Respondents with gastro-oesophageal reflux disease (GERD) report having a variety of atypical manifestations. The relationship between these manifestations and disease severity, night-time GERD and functioning has not been determined. AIM: To determine if atypical manifestations are related to increased disease severity, night-time GERD and decreased functioning. METHODS: A web survey among US adults was conducted, using a validated GERD screener. Frequency of night-time and daytime typical symptoms (acid regurgitation and heartburn) and atypical manifestations were assessed. Respondents were classified as night-time GERD or daytime GERD based on typical symptom frequency. Prevalence of frequent atypical manifestations (> or =2 days or nights/week) was assessed. RESULTS: Gastro-oesophageal reflux disease cases had a higher prevalence of each atypical manifestation (P < 0.05 for all) compared with controls. Night-time GERD respondents had a higher prevalence of atypical manifestations compared with daytime GERD respondents (P < 0.05 for most manifestations) and the prevalence of atypical manifestations increased with GERD symptom severity (P < 0.05 for most). Those with atypical manifestations reported lower functioning scores (P < 0.05 for most). CONCLUSIONS: Respondents with typical GERD symptoms commonly report atypical manifestations, especially those with night-time symptoms and those with greater underlying GERD severity. Respondents with GERD and atypical manifestations had more impaired functioning than those with typical symptoms only.


Subject(s)
Circadian Rhythm , Gastroesophageal Reflux , Quality of Life , Severity of Illness Index , Adult , Cross-Sectional Studies , Female , Gastroesophageal Reflux/complications , Gastroesophageal Reflux/epidemiology , Gastroesophageal Reflux/psychology , Health Surveys , Humans , Male , Middle Aged , Prevalence , Surveys and Questionnaires
8.
Cancer Gene Ther ; 13(1): 107-14, 2006 Jan 01.
Article in English | MEDLINE | ID: mdl-16052228

ABSTRACT

Thymidylate synthase (TS) is an essential enzyme that synthesizes thymidylic acid in the de novo biosynthetic pathway. Inhibiting TS enzyme activity with substrate or cofactor analogs leads to inhibition of DNA replication and cell death. For this reason, TS is an important target enzyme for cancer chemotherapeutic drugs. We describe an alternative approach to reducing cellular TS enzyme activity using short interfering RNA (siRNA) technology to lower TS mRNA levels. Plasmids that direct the synthesis of siRNAs that target nucleotides 898-916 and 965-983 (relative to the A of the translational start codon) of human TS mRNA were highly effective at reducing TS enzyme levels in transient transfection assays. Infection of HeLa cells with retroviruses that contain the effective siRNA genes led to a stable 80-95% reduction of TS enzyme and mRNA. A similar percent reduction in TS expression was observed in a cell line that overproduces TS enzyme 100-fold due to TS gene amplification. Cells that exhibited the greatest reduction in TS enzyme level grew poorly in medium that lacked thymidine. These observations suggest that siRNA approaches may provide an alternative therapeutic strategy to reduce TS enzyme levels.


Subject(s)
RNA, Small Interfering/pharmacology , Thymidylate Synthase/metabolism , Animals , Base Sequence , Cell Proliferation , Cricetinae , Fibroblasts/metabolism , HeLa Cells , Humans , Molecular Sequence Data , RNA, Messenger/metabolism , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Thymidylate Synthase/genetics , Time Factors , Transfection
9.
Sex Transm Infect ; 81(4): 287-93, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16061532

ABSTRACT

OBJECTIVES: To review studies of sexually transmitted infection (STI) prevalence in South Africa between 1985 and 2003 in selected sentinel populations. To examine how STI prevalence varies between populations and to identify the limitations of the existing data. METHODS: Studies of the prevalence of syphilis, chancroid, granuloma inguinale, lymphogranuloma venereum, gonorrhoea, chlamydia, trichomoniasis, bacterial vaginosis, candidiasis, and herpes simplex virus type 2 (HSV-2) were considered. Results were included if they related to women attending antenatal clinics or family planning clinics, commercial sex workers, individuals in the general population (household surveys), patients with STIs, patients with genital ulcer disease (GUD), or men with urethritis. RESULTS: High STI prevalence rates have been measured, particularly in the case of HSV-2, trichomoniasis, bacterial vaginosis and candidiasis. The aetiological profile of GUD appears to be changing, with more GUD caused by HSV-2 and less caused by chancroid. The prevalence of gonorrhoea and syphilis is highest in "high risk" groups such as sex workers and attenders of STI clinics, but chlamydia and trichomoniasis prevalence levels are not significantly higher in these groups than in women attending antenatal clinics. CONCLUSIONS: The prevalence of STIs in South Africa is high, although there is extensive variability between regions. There is a need for STI prevalence data that are more nationally representative and that can be used to monitor prevalence trends more reliably.


Subject(s)
Sexually Transmitted Diseases/epidemiology , Adolescent , Adult , Female , Humans , Male , Prevalence , Rural Health , Sentinel Surveillance , South Africa/epidemiology , Urban Health
10.
Aliment Pharmacol Ther ; 20 Suppl 9: 39-46, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15527463

ABSTRACT

Gastro-oesophageal reflux disease (GERD) is among the most common gastrointestinal conditions in the USA. For most symptomatic patients, reflux events occur during both daytime and night-time hours. Whereas daytime reflux events tend to be frequent but brief, reflux events that occur during sleep are comparatively less frequent but significantly longer. Longer oesophageal acid-clearance and acid-mucosal contact times during sleep are at least partly due to several physiological changes associated with sleep, including dramatic declines in saliva production and frequency of swallowing, decreased conscious perception of heartburn and consequent arousal and clearance behaviours, and slower gastric emptying. Obstructive sleep apnea syndrome and obesity seem to predispose some patients to nocturnal GERD, and the presence of either of these conditions may help to identify patients with symptoms consistent with GERD. Recognition and treatment of night-time GERD are important because it can be associated with decreased quality of life (including sleep disruption) and increased risk of serious oesophageal and respiratory complications.


Subject(s)
Gastroesophageal Reflux/complications , Sleep Wake Disorders/etiology , Circadian Rhythm , Deglutition/physiology , Gastroesophageal Reflux/physiopathology , Heartburn/etiology , Humans , Hydrogen-Ion Concentration , Obesity/complications , Postprandial Period , Saliva/metabolism , Sleep Apnea, Obstructive/etiology , Sleep Wake Disorders/physiopathology
11.
Ann Otol Rhinol Laryngol ; 110(10): 982-4, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11642434

ABSTRACT

This study was performed to evaluate the incidence of metastasis at level I in patients with squamous laryngeal cancer. One hundred consecutive patients with squamous carcinoma of the larynx were submitted to surgical treatment including radical neck dissection. The tumor stage was T3 or T4, and the neck stage was N1-N2c. Lymph node metastases were pathologically confirmed in 80 patients. Metastases were concentrated within level II in 59% of cases, level III in 17% of cases, level IV in 11% of cases, and level V in 6% of cases. Only 2 patients (2%) had detectable tumors in the lymph nodes of the submandibular triangle (level IB). This study shows that patients with laryngeal cancer rarely present metastases at the submandibular triangle, even in advanced local disease with cervical metastasis staged as N1 to N2c. Therefore, dissection of the submandibular triangle is indicated only in the presence of clinical, radiographic, or cytologic evidence of metastatic disease at level I.


Subject(s)
Carcinoma, Squamous Cell/pathology , Laryngeal Neoplasms/pathology , Lymph Nodes/pathology , Adult , Aged , Aged, 80 and over , Female , Humans , Lymphatic Metastasis/pathology , Male , Middle Aged , Neck , Retrospective Studies
18.
Virus Res ; 73(1): 57-65, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11163644

ABSTRACT

Cytomegalovirus (CMV) replication in non-proliferating cells requires the coordinated expression of the host enzymes responsible for deoxyribonucleotide synthesis. Thymidylate synthase (TS) is an essential cellular enzyme that catalyzes de novo synthesis of thymidylic acid (dTMP). In this report we show that murine CMV (MCMV) replication and DNA synthesis are inhibited in quiescent 3T6 fibroblasts by raltitrexed, a quinazoline-based folate analog that specifically inhibits TS. This antiviral activity was abrogated in LU3-7 cells, a 3T6 derivative that overproduces TS by about 50-fold. These observations indicate that the anticytomegaloviral activity of raltitrexed is associated with TS inhibition and suggest that cellular TS activity is required for efficient CMV replication in quiescent cells.


Subject(s)
Antiviral Agents/pharmacology , Cytomegalovirus/drug effects , Quinazolines/pharmacology , Thiophenes/pharmacology , Thymidylate Synthase/antagonists & inhibitors , Animals , Cell Line , Cytomegalovirus/physiology , Enzyme Inhibitors/pharmacology , Mice , Thymidylate Synthase/biosynthesis , Virus Replication/drug effects
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