Browsing by Author "Madhi, Shabir A."
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- ItemThe association between the ratio of monocytes : lymphocytes at age 3 months and risk of tuberculosis (TB) in the first two years of life(BioMed Central, 2014-07-17) Naranbhai, Vivek; Kim, Soyeon; Fletcher, Helen; Cotton, Mark F.; Violari, Avy; Mitchell, Charles; Nachman, Sharon; McSherry, George; McShane, Helen; Hill, Adrian V. S.; Madhi, Shabir A.Background: Recent transcriptomic studies revived a hypothesis suggested by historical studies in rabbits that the ratio of peripheral blood monocytes to lymphocytes (ML) is associated with risk of tuberculosis (TB) disease. Recent data confirmed the hypothesis in cattle and in adults infected with HIV. Methods: We tested this hypothesis in 1,336 infants (540 HIV-infected, 796 HIV-exposed, uninfected (HEU)) prospectively followed in a randomized controlled trial of isoniazid prophylaxis in Southern Africa, the IMPAACT P1041 study. We modeled the relationship between ML ratio at enrollment (91 to 120 days after birth) and TB disease or death in HIV-infected children and latent Mycobacterium tuberculosis (MTB) infection, TB disease or death in HEU children within 96 weeks (with 12 week window) of randomization. Infants were followed-up prospectively and routinely assessed for MTB exposure and outcomes. Cox proportional hazards models allowing for non-linear associations were used; in all cases linear models were the most parsimonious. Results: Increasing ML ratio at baseline was significantly associated with TB disease/death within two years (adjusted hazard ratio (HR) 1.17 per unit increase in ML ratio; 95% confidence interval (CI) 1.01 to 1.34; P = 0.03). Neither monocyte count nor lymphocyte counts alone were associated with TB disease. The association was not statistically dissimilar between HIV infected and HEU children. Baseline ML ratio was associated with composite endpoints of TB disease and death and/or TB infection. It was strongest when restricted to probable and definite TB disease (HR 1.50; 95% CI 1.19 to 1.89; P = 0.006). Therefore, per 0.1 unit increase in the ML ratio at three to four months of age, the hazard of probable or definite TB disease before two years was increased by roughly 4% (95% CI 1.7% to 6.6%). Conclusion: Elevated ML ratio at three- to four-months old is associated with increased hazards of TB disease before two years among children in Southern Africa. While significant, the modest effect size suggests that the ML ratio plays a modest role in predicting TB disease-free survival; its utility may, therefore, be limited to combination with existing tools to stratify TB risk, or to inform underlying pathophysiologic determinants of TB disease.
- ItemEarly antiretroviral therapy reduces the incidence of otorrhea in a randomized study of early and deferred antiretroviral therapy : evidence from the Children with HIV Early antiretroviral therapy (CHER) Study.(2011-10) Hainline, Clotilde; Taliep, Reghana; Sorour, Gill; Nachman, Sharon; Rabie, Helena; Dobbels, Els; Janse van Rensburg, Anita; Cornell, Morna; Violari, Avy; Madhi, Shabir A.; Cotton, Mark F.Abstract Background Although otorrhea occurs commonly in HIV-infected infants, there are few data. We compared the incidence of otorrhea in infants receiving early vs deferred ART in the Children with HIV Early Antiretroviral (CHER) trial. Infants aged 6 to 12 weeks of age with confirmed HIV infection and a CD4 percentage greater than or equal to 25% were randomized to early or deferred ART at two sites in South Africa. Medical records from one study site were reviewed for otorrhea. Findings Data were reviewed from the start of the trial in July 2005 until 20 June 2007, when the Data Safety Monitoring Board recommended that randomization to the deferred arm should stop and that all infants in this arm be reviewed for commencing antiretroviral therapy. Infants entered the study at a median of 7.4 weeks of age. Eleven of 38 (29%) on deferred therapy and 7 of 75 (9%) in the early-therapy group developed otorrhea (risk ratio 3.1, 95% confidence interval (CI) 1.31-7.36; p = 0.01). Conclusions Early initiation of antiretroviral therapy is associated with significantly less otorrhea than when a deferred strategy is followed. Trial registration NCT00102960. ClinicalTrials.Gov
- ItemEffectiveness of the 13-valent pneumococcal conjugate vaccine against invasive pneumococcal disease in South African children : a case-control study(Elsevier, 2017-01-27) Cohen, Cheryl; Von Mollendorf, Claire; De Gouveia, Linda; Lengana, Sarona; Meiring, Susan; Quan, Vanessa; Nguweneza, Arthermon; Moore, David P.; Reubenson, Gary; Moshe, Mamokgethi; Madhi, Shabir A.; Eley, Brian; Hallbauer, Ute; Finlayson, Heather; Varughese, Sheeba; O'Brien, Katherine L.; Zell, Elizabeth R.; Klugman, Keith P.; Whitney, Cynthia G.; Von Gottberg, AnneBackground: The 13-valent pneumococcal conjugate vaccine (PCV13) was designed to include disease-causing serotypes that are important in low-income and middle-income countries. Vaccine eff ectiveness estimates are scarce in these settings. South Africa replaced PCV7 with PCV13 in 2011 using a 2 + 1 schedule. We aimed to assess the eff ectiveness of two or more doses of PCV13 against invasive pneumococcal disease in children with HIV infection and in those not infected with HIV. Methods: Cases of invasive pneumococcal disease in children aged 5 years or younger were identifi ed through national laboratory-based surveillance. Isolates were serotyped with the Quellung reaction or PCR. We sought in-hospital controls for every case, matched for age, HIV status, and study site. We aimed to enrol four controls for every case not infected with HIV and six controls for every case with HIV infection (case-control sets). With conditional logistic regression, we calculated vaccine eff ectiveness as a percentage, with the equation 1 – [adjusted odds ratio for vaccination] × 100. We included data from an earlier investigation of PCV7 to assess vaccine eff ectiveness in children exposed to but not infected with HIV and in malnourished children not infected with HIV. Findings: Between January, 2012, and December, 2014, we enrolled children aged 16 weeks or older to our study: 240 were cases not infected with HIV, 75 were cases with HIV infection, 1118 were controls not infected with HIV, and 283 were controls with HIV infection. The eff ectiveness of two or more doses of PCV13 against PCV13-serotype invasive pneumococcal disease was 85% (95% CI 37 to 96) among 11 case-control sets of children not infected with HIV and 91% (–35 to 100) among three case-control sets of children with HIV infection. PCV13 eff ectiveness among 26 case-control sets of children not infected with HIV was 52% (95% CI –12 to 79) against all-serotype invasive pneumococcal disease and 94% (44 to 100) for serotype 19A. Vaccine eff ectiveness against PCV7-serotype invasive pneumococcal disease was 87% (95% CI 38 to 97) in children exposed to HIV but uninfected and 90% (53 to 98) in malnourished children not infected with HIV. Interpretation: Our results indicate that PCV13 in a 2 + 1 schedule is eff ective for preventing vaccine-type pneumococcal infections in young children not infected with HIV, including those who are malnourished or who have been exposed to HIV. Although the point estimate for PCV13 vaccine eff ectiveness in children infected with HIV was high, it did not reach signifi cance, possibly because of the small sample size. These fi ndings support recommendations for widespread use of pneumococcal conjugate vaccine in low-income and middle-income countries.
- ItemFactors influencing access of pregnant women and their infants to their local healthcare system : a prospective, multi-centre, observational study(BioMed Central, 2018-01-15) Madhi, Shabir A.; Rivera, Luis M.; Saez-Llorens, Xavier; Menendez, Clara; Carrim-Ganey, Nazira; Cotton, Mark F.; Katzman, Darren; Luttig, Marietha M.; Candelario, Rosalba; Baker, Sherryl; Roychoudhury, MahuaBackground: The successful implementation of maternal vaccination relies on results of clinical trials, considering the prenatal and postnatal attendance at selected healthcare institutions. This study evaluated factors influencing maternal/infant access to healthcare facilities to identify potential barriers to participation in future clinical trials on maternal vaccination. Methods In this prospective, multi-centre, observational study, pregnant women (N = 3243) were enrolled at ten sites across Panama, the Dominican Republic, South Africa, and Mozambique between 2012 and 2014. They completed questionnaires at enrolment, delivery, and infant follow-up (90 days post-partum) visits, including questions on transportation, phone accessibility, alternative childcare, gestational age at enrolment, delivery location, and health status of their infant. Logistic regression was used to identify factors significantly associated with return to study site for delivery or infant follow-up visits. Results: Among 3229 enrolled women with delivery information, 63.6% (range across sites: 25.3–91.5%) returned to study site for delivery. Older women and those at later gestational age at enrolment were more likely to deliver at the study site. While heterogeneities were observed at site level, shorter travel time at delivery and increased transportation costs at enrolment were associated with increased likelihood of women returning to study site for delivery. Among 3145 women with live-born infants, 3077 (95.3%) provided 90-day follow-up information; of these, 68.9% (range across sites: 25.6–98.9%) returned to study site for follow-up visits. Women with other children and with lower transportation costs at delivery were more likely to return to study site for follow-up visits. Among 666 infants reported sick, 94.3% were taken to a healthcare facility, with only 41.9% (range across sites: 4.9–77.3%) to the study site. Conclusion: Although high retention was observed from enrolment through 90 days after delivery, post-partum surveillance should be broadened beyond the study sites and additional follow-up visits should be planned within the neonatal period. The factors influencing maternal/infant access to healthcare facilities and the issues identified in this study should be taken into consideration in planning future clinical studies on maternal immunisation in low- and middle-income countries.
- ItemGuidelines for the vaccination of HIV-infected adolescents and adults in South Africa(Medpharm Publications, 2018) Dlamini, Sipho K.; Madhi, Shabir A.; Muloiwa, Rudzani; Von Gottberg, Anne; Moosa, Mahomed-Yunus S.; Meiring, Susan T.; Wiysonge, Charles S.; Hefer, Eric; Mulaudzi, Muhangwi B.; Nuttall, James; Moorhouse, Michelle; Kagina, Benjamin M.No abstract available.
- ItemHIV infection and the epidemiology of Invasive Pneumococcal Disease (IPD) in South African adults and older children prior to the introduction of a Pneumococcal Conjugate Vaccine (PCV)(Public Library of Science, 2016) Meiring, Susan; Cohen, Cheryl; Quan, Vanessa; De Gouveia, Linda; Feldman, Charles; Karstaedt, Alan; Klugman, Keith P.; Madhi, Shabir A.; Rabie, Helene; Sriruttan, Charlotte; Von Gottberg, Anne; GERMS-SAIntroduction: Streptococcus pneumoniae is the commonest cause of bacteremic pneumonia among HIV-infected persons. As more countries with high HIV prevalence are implementing infant pneumococcal conjugate vaccine (PCV) programs, we aimed to describe the baseline clinical characteristics of adult invasive pneumococcal disease (IPD) in the pre-PCV era in South Africa in order to interpret potential indirect effects following vaccine use. Methods: National, active, laboratory-based surveillance for IPD was conducted in South Africa from 1 January 2003 through 31 December 2008. At 25 enhanced surveillance (ES) hospital sites, clinical data, including HIV serostatus, were collected from IPD patients ≥ 5 years of age. We compared the clinical characteristics of individuals with IPD in those HIV-infected and -uninfected using multivariable analysis. PCV was introduced into the routine South African Expanded Program on Immunization (EPI) in 2009. Results: In South Africa, from 2003–2008, 17 604 cases of IPD occurred amongst persons ≥ 5 years of age, with an average incidence of 7 cases per 100 000 person-years. Against a national HIV-prevalence of 18%, 89% (4190/4734) of IPD patients from ES sites were HIV-infected. IPD incidence in HIV-infected individuals is 43 times higher than in HIV-uninfected persons (52 per 100 000 vs. 1.2 per 100 000), with a peak in the HIV-infected elderly population of 237 per 100 000 persons. Most HIV-infected individuals presented with bacteremia (74%, 3 091/4 190). HIV-uninfected individuals were older; and had more chronic conditions (excluding HIV) than HIV-infected persons (39% (210/544) vs. 19% (790/4190), p<0.001). During the pre-PCV immunization era in South Africa, 71% of serotypes amongst HIV-infected persons were covered by PCV13 vs. 73% amongst HIV-uninfected persons, p = 0.4, OR 0.9 (CI 0.7–1.1). Conclusion: Seventy to eighty-five percent of adult IPD in the pre-PCV era were vaccine serotypes and 93% of cases had recognized risk factors (including HIV-infection) for pneumococcal vaccination. These data describe the epidemiology of IPD amongst HIV-infected and -uninfected adults during the pre-PCV era and provide a robust baseline to calculate the indirect effect of PCV in future studies.
- ItemSafety of licensed vaccines in HIV-infected persons : a systematic review protocol(BioMed Central, 2014-09) Kagina, Benjamin M.; Wiysonge, Charles S.; Lesosky, Maia; Madhi, Shabir A.; Hussey, Gregory D.Background Safety of vaccines remains a cornerstone of building public trust on the use of these cost-effective and life-saving public health interventions. In some settings, particularly Sub-Saharan Africa, there is a high prevalence of HIV infection and a high burden of vaccine-preventable diseases. There is evidence suggesting that the immunity induced by some commonly used vaccines is not durable in HIV-infected persons, and therefore, repeated vaccination may be considered to ensure optimal vaccine-induced immunity in this population. However, some vaccines, particularly the live vaccines, may be unsafe in HIV-infected persons. There is lack of evidence on the safety profile of commonly used vaccines among HIV-infected persons. We are therefore conducting a systematic review to assess the safety profile of routine vaccines administered to HIV-infected persons. Methods/Design We will select studies conducted in any setting where licensed and effective vaccines were administered to HIV-infected persons. We will search for eligible studies in PubMed, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, Africa-Wide, PDQ-Evidence and CINAHL as well as reference lists of relevant publications. We will screen search outputs, select studies and extract data in duplicate, resolving discrepancies by discussion and consensus. Discussion Globally, immunisation is a major public health strategy to mitigate morbidity and mortality caused by various infectious disease-causing agents. In general, there are efforts to increase vaccination coverage worldwide, and for these efforts to be successful, safety of the vaccines is paramount, even among people living with HIV, who in some situations may require repeated vaccination. Results from this systematic review will be discussed in the context of the safety of routine vaccines among HIV-infected persons. From the safety perspective, we will also discuss whether repeat vaccination strategies may be feasible among HIV-infected persons. Systematic review registration PROSPERO CRD42014009794.
- ItemTreatment and outcomes in children with multidrug-resistant tuberculosis : a systematic review and individual patient data meta-analysis.(Public Library of Science, 2018-07-11) Harausz, Elizabeth P.; Garcia-Prats, Anthony J.; Law, Stephanie; Schaaf, H. Simon; Kredo, Tamara; Seddon, James A.; Menzies, Dick; Turkova, Anna; Achar, Jay; Amanullah, Farhana; Barry, Pennan; Becerra, Mercedes; Chan, Edward D.; Chan, Pei Chun; Chiotan, Domnica Ioana; Crossa, Aldo; Drobac, Peter C.; Fairlie, Lee; Falzon, Dennis; Flood, Jennifer; Gegia, Medea; Hicks, Robert M.; Isaakidis, Petros; Kadri, S. M.; Kampmann, Beate; Madhi, Shabir A.; Marais, Else; Mariandyshev, Andrei; Mendez-Echevarria, Ana; Moore, Brittany Kathryn; Nargiza, Parpieva; Ozere, Iveta; Padayatchi, Nesri; Ur-Rehman, Saleem; Rybak, Natasha; Santiago-Garcia, Begona; Shah, N. Sarita; Sharma, Sangeeta; Shim, Tae Sun; Skrahina, Alena; Soriano-Arandes, Antoni; Van Den Boom, Martin; Van Der Werf, Marieke J.; Van Der Werf, Tjip S.; Williams, Bhanu; Yablokova, Elena; Yim, Jae-Joon; Furin, Jennifer; Hesseling, Anneke C.Background: An estimated 32,000 children develop multidrug-resistant tuberculosis (MDR-TB; Mycobacterium tuberculosis resistant to isoniazid and rifampin) each year. Little is known about the optimal treatment for these children. Methods and findings: To inform the pediatric aspects of the revised World Health Organization (WHO) MDR-TB treatment guidelines, we performed a systematic review and individual patient data (IPD) meta-analysis, describing treatment outcomes in children treated for MDR-TB. To identify eligible reports we searched PubMed, LILACS, Embase, The Cochrane Library, PsychINFO, and BioMedCentral databases through 1 October 2014. To identify unpublished data, we reviewed conference abstracts, contacted experts in the field, and requested data through other routes, including at national and international conferences and through organizations working in pediatric MDR-TB. A cohort was eligible for inclusion if it included a minimum of three children (aged <15 years) who were treated for bacteriologically confirmed or clinically diagnosed MDR-TB, and if treatment outcomes were reported. The search yielded 2,772 reports; after review, 33 studies were eligible for inclusion, with IPD provided for 28 of these. All data were from published or unpublished observational cohorts. We analyzed demographic, clinical, and treatment factors as predictors of treatment outcome. In order to obtain adjusted estimates, we used a random-effects multivariable logistic regression (random intercept and random slope, unless specified otherwise) adjusted for the following covariates: age, sex, HIV infection, malnutrition, severe extrapulmonary disease, or the presence of severe disease on chest radiograph. We analyzed data from 975 children from 18 countries; 731 (75%) had bacteriologically confirmed and 244 (25%) had clinically diagnosed MDR-TB. The median age was 7.1 years. Of 910 (93%) children with documented HIV status, 359 (39%) were infected with HIV. When compared to clinically diagnosed patients, children with confirmed MDR-TB were more likely to be older, to be infected with HIV, to be malnourished, and to have severe tuberculosis (TB) on chest radiograph (p < 0.001 for all characteristics). Overall, 764 of 975 (78%) had a successful treatment outcome at the conclusion of therapy: 548/731 (75%) of confirmed and 216/244 (89%) of clinically diagnosed children (absolute difference 14%, 95% confidence interval [CI] 8%±19%, p < 0.001). Treatment was successful in only 56% of children with bacteriologically confirmed TB who were infected with HIV who did not receive any antiretroviral treatment (ART) during MDR-TB therapy, compared to 82% in children infected with HIV who received ART during MDR-TB therapy (absolute difference 26%, 95% CI 5%±48%, p = 0.006). In children with confirmed MDR-TB, the use of second-line injectable agents and high-dose isoniazid (15± 20 mg/kg/day) were associated with treatment success (adjusted odds ratio [aOR] 2.9, 95% CI 1.0±8.3, p = 0.041 and aOR 5.9, 95% CI 1.7±20.5, p = 0.007, respectively). These findings for high-dose isoniazid may have been affected by site effect, as the majority of patients came from Cape Town. Limitations of this study include the difficulty of estimating the treatment effects of individual drugs within multidrug regimens, only observational cohort studies were available for inclusion, and treatment decisions were based on the clinician's perception of illness, with resulting potential for bias. Conclusions: This study suggests that children respond favorably to MDR-TB treatment. The low success rate in children infected with HIV who did not receive ART during their MDR-TB treatment highlights the need for ART in these children. Our findings of individual drug effects on treatment outcome should be further evaluated.
- ItemUpdated recommendations for the management of upper respiratory tract infections in South Africa(Health & Medical Publishing Group, 2015) Brink, Adrian J.; Cotton, Mark F.; Feldman, Charles; Finlayson, Heather; Friedman, Ray L.; Green, Robin; Hendson, Willy; Hockman, Maurice H.; Maartens, Gary; Madhi, Shabir A.; Reubenson, Gary; Silverbauer, Eddie J.; Zietsman, Inge L.Background. Inappropriate use of antibiotics for non-severe upper respiratory tract infections (URTIs), most of which are viral, significantly adds to the burden of antibiotic resistance. Since the introduction of pneumococcal conjugate vaccines in South Africa in 2009, the relative frequency of the major bacterial pathogens causing acute otitis media (AOM) and acute bacterial rhinosinusitis (ABRS) has changed. Recommendations. Since URTIs are mostly viral in aetiology and bacterial AOM and ABRS frequently resolve spontaneously, these recommendations include diagnostic criteria to assist in separating viral from bacterial causes and hence select those patients who do not require antibiotics. Penicillin remains the drug of choice for tonsillopharyngitis and amoxicillin the drug of choice for both AOM and ABRS. A dose of 90 mg/kg/d is recommended for children, which should be effective for pneumococci with high-level penicillin resistance and will also cover most infections with Haemophilus influenzae. Amoxicillin-clavulanate (in high-dose amoxicillin formulations available for both children and adults) should be considered the initial treatment of choice in patients with recent antibiotic therapy with amoxicillin (previous 30 days) and with resistant H. influenzae infections pending the results of studies of local epidemiology (β-lactamase production ≥15%). The macrolide/azalide class of antibiotics is not recommended routinely for URTIs and is reserved for β-lactam-allergic patients. Conclusion. These recommendations should facilitate rational antibiotic prescribing for URTIs as a component of antibiotic stewardship. They will require updating when new information becomes available, particularly from randomised controlled trials and surveillance studies of local aetiology and antibiotic susceptibility patterns.
- ItemUtility of clinical parameters to identify HIV infection in infants below ten weeks of age in South Africa : a prospective cohort study(BioMed Central, 2011-11) Jaspan, Heather B.; Myer, Landon; Madhi, Shabir A.; Violari, Avy; Gibb, Diana M.; Stevens, Wendy S.; Dobbels, Els; Cotton, Mark F.ABSTRACT: Background: As HIV-infected infants have high mortality, the World Health Organization now recommends initiating antiretroviral therapy as early as possible in the first year of life. However, in many settings, laboratory diagnosis of HIV in infants is not readily available. We aimed to develop a clinical algorithm for HIV presumptive diagnosis in infants < 10 weeks old using screening data from the Children with HIV Early Antiretroviral therapy (CHER) study in South Africa. HIV-infected and HIV-uninfected exposed infants < 10 weeks of age were identified through Vertical Transmission Prevention programs. Clinical and laboratory data were systematically recorded, groups were compared using Kruskal-Wallis, analysis of variance (ANOVA), and Fisher's exact tests. Receiver Operating Characteristic (ROC) curves were compiled using combinations of clinical findings. Results 417 HIV-infected and 125 HIV-exposed, uninfected infants, median age 46 days (IQR 38-55), were included. The median CD4 percentage in HIV-infected infants was 34 (IQR 28-41)%. HIV-infected infants had lower weight-for-age, more lymphadenopathy, oral thrush, and hepatomegaly than exposed uninfected infants (Adjusted Odds Ratio 0.51, 8.8, 5.6 and 23.5 respectively; p < 0.001 for all). Sensitivity of individual signs was low (< 20%) but specificity high (98-100%). If any one of oral thrush, hepatomegaly, splenomegaly, lymphadenopathy, diaper dermatitis, weight < 50th centile are present, sensitivity for HIV infection amongst HIV-exposed infants was 86%. These algorithms performed similarly when used to predict severe immune suppression. Conclusions A combination of physical findings is helpful in identifying infants most likely to be HIV-infected. This may inform management algorithms and provide guidance for focused laboratory testing in some settings, and should be further validated in these settings and elsewhere.