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Odutola A, Ota MOC, Antonio M, Ogundare EO, Saidu Y, Foster-Nyarko E, Owiafe PK, Ceesay F, Worwui A, Idoko OT, Owolabi O, Bojang A, Jarju S, Drammeh I, Kampmann B, Greenwood BM, Alderson M, Traskine M, Devos N, Schoonbroodt S, Swinnen K, Verlant V, Dobbelaere K, Borys D. Efficacy of a novel, protein-based pneumococcal vaccine against nasopharyngeal carriage of Streptococcus pneumoniae in infants: A phase 2, randomized, controlled, observer-blind study. Vaccine 2017; 35:2531-2542. [PMID: 28389097 DOI: 10.1016/j.vaccine.2017.03.071] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 03/21/2017] [Accepted: 03/22/2017] [Indexed: 01/30/2023]
Abstract
BACKGROUND Conserved pneumococcal proteins are potential candidates for inclusion in vaccines against pneumococcal diseases. In the first part of a two-part study, an investigational vaccine (PHiD-CV/dPly/PhtD-30) containing 10 pneumococcal serotype-specific polysaccharide conjugates (10VT) combined with pneumolysin toxoid and pneumococcal histidine triad protein D (30μg each) was well tolerated by Gambian children. Part two, presented here, assessed the efficacy of two PHiD-CV/dPly/PhtD formulations against pneumococcal nasopharyngeal carriage (NPC) prevalence in infants. METHODS In this phase 2, randomized, controlled, observer-blind trial, healthy infants aged 8-10weeks, recruited from a peri-urban health center, were randomized (1:1:1:1:1:1) into six groups. Four groups received PHiD-CV/dPly/PhtD (10 or 30μg of each protein), PHiD-CV, or 13-valent pneumococcal conjugate vaccine at ages 2-3-4months (3+0 infant schedule) and two groups PHiD-CV/dPly/PhtD-30 or PHiD-CV at 2-4-9months (2+1 infant schedule). The primary objective was impact on non-10VT NPC at ages 5-9-12months. Secondary objectives included confirmatory analysis of protein dose superiority and safety/reactogenicity. Impact on pneumococcal NPC acquisition, bacterial load, and ply and phtD gene sequencing were explored. RESULTS 1200 infants were enrolled between June 2011 and May 2012. Prevalences of pneumococcal (60-67%) and non-10VT (55-61%) NPC were high at baseline. Across all post-vaccination time points, efficacy of PHiD-CV/dPly/PhtD-10 and PHiD-CV/dPly/PhtD-30 against non-10VT NPC (3+0 schedule) was 1.1% (95% CI -21.5, 19.5) and 2.1% (-20.3, 20.3), respectively; efficacy of PHiD-CV/dPly/PhtD-30 (2+1 schedule) was 0.5% (-22.1, 18.9) versus PHiD-CV. No differences were observed in pneumococcal NPC acquisition, clearance, or bacterial load. Both protein-based vaccines elicited immune responses to pneumococcal proteins. CONCLUSIONS In this high carriage prevalence setting, inclusion of pneumococcal proteins in the PHiD-CV/dPly/PhtD investigational vaccine had no impact on pneumococcal NPC in infants, regardless of protein dose or schedule. Future evaluations will assess its impact against pneumococcal disease endpoints. FUNDING PATH, GlaxoSmithKline Biologicals SA. ClinicalTrials.gov identifier NCT01262872.
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Research Support, Non-U.S. Gov't |
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Bertola LD, Jongbloed H, van der Gaag KJ, de Knijff P, Yamaguchi N, Hooghiemstra H, Bauer H, Henschel P, White PA, Driscoll CA, Tende T, Ottosson U, Saidu Y, Vrieling K, de Iongh HH. Phylogeographic Patterns in Africa and High Resolution Delineation of Genetic Clades in the Lion (Panthera leo). Sci Rep 2016; 6:30807. [PMID: 27488946 PMCID: PMC4973251 DOI: 10.1038/srep30807] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 07/08/2016] [Indexed: 11/10/2022] Open
Abstract
Comparative phylogeography of African savannah mammals shows a congruent pattern in which populations in West/Central Africa are distinct from populations in East/Southern Africa. However, for the lion, all African populations are currently classified as a single subspecies (Panthera leo leo), while the only remaining population in Asia is considered to be distinct (Panthera leo persica). This distinction is disputed both by morphological and genetic data. In this study we introduce the lion as a model for African phylogeography. Analyses of mtDNA sequences reveal six supported clades and a strongly supported ancestral dichotomy with northern populations (West Africa, Central Africa, North Africa/Asia) on one branch, and southern populations (North East Africa, East/Southern Africa and South West Africa) on the other. We review taxonomies and phylogenies of other large savannah mammals, illustrating that similar clades are found in other species. The described phylogeographic pattern is considered in relation to large scale environmental changes in Africa over the past 300,000 years, attributable to climate. Refugial areas, predicted by climate envelope models, further confirm the observed pattern. We support the revision of current lion taxonomy, as recognition of a northern and a southern subspecies is more parsimonious with the evolutionary history of the lion.
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Clarke E, Saidu Y, Adetifa JU, Adigweme I, Hydara MB, Bashorun AO, Moneke-Anyanwoke N, Umesi A, Roberts E, Cham PM, Okoye ME, Brown KE, Niedrig M, Chowdhury PR, Clemens R, Bandyopadhyay AS, Mueller J, Jeffries DJ, Kampmann B. Safety and immunogenicity of inactivated poliovirus vaccine when given with measles-rubella combined vaccine and yellow fever vaccine and when given via different administration routes: a phase 4, randomised, non-inferiority trial in The Gambia. LANCET GLOBAL HEALTH 2016; 4:e534-47. [PMID: 27364568 DOI: 10.1016/s2214-109x(16)30075-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 04/17/2016] [Accepted: 04/27/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND The introduction of the inactivated poliovirus vaccine (IPV) represents a crucial step in the polio eradication endgame. This trial examined the safety and immunogenicity of IPV given alongside the measles-rubella and yellow fever vaccines at 9 months and when given as a full or fractional dose using needle and syringe or disposable-syringe jet injector. METHODS We did a phase 4, randomised, non-inferiority trial at three periurban government clinics in west Gambia. Infants aged 9-10 months who had already received oral poliovirus vaccine were randomly assigned to receive the IPV, measles-rubella, and yellow fever vaccines, singularly or in combination. Separately, IPV was given as a full intramuscular or fractional intradermal dose by needle and syringe or disposable-syringe jet injector at a second visit. The primary outcomes were seroprevalence rates for poliovirus 4-6 weeks post-vaccination and the rate of seroconversion between baseline and post-vaccination serum samples for measles, rubella, and yellow fever; and the post-vaccination antibody titres generated against each component of the vaccines. We did a per-protocol analysis with a non-inferiority margin of 10% for poliovirus seroprevalence and measles, rubella, and yellow fever seroconversion, and (1/3) log2 for log2-transformed antibody titres. This trial is registered with ClinicalTrials.gov, number NCT01847872. FINDINGS Between July 10, 2013, and May 8, 2014, we assessed 1662 infants for eligibility, of whom 1504 were enrolled into one of seven groups for vaccine interference and one of four groups for fractional dosing and alternative route of administration. The rubella and yellow fever antibody titres were reduced by co-administration but the seroconversion rates achieved non-inferiority in both cases (rubella, -4·5% [95% CI -9·5 to -0·1]; yellow fever, 1·2% [-2·9 to 5·5]). Measles and poliovirus responses were unaffected (measles, 6·8% [95% CI -1·4 to 14·9]; poliovirus serotype 1, 1·6% [-6·7 to 4·7]; serotype 2, 0·0% [-2·1 to 2·1]; serotype 3, 0·0% [-3·8 to 3·9]). Poliovirus seroprevalence was universally high (>97%) after vaccination, but the antibody titres generated by fractional intradermal doses of IPV did not achieve non-inferiority compared with full dose. The number of infants who seroconverted or had a four-fold rise in titres was also lower by the intradermal route. There were no safety concerns. INTERPRETATION The data support the future co-administration of IPV, measles-rubella, and yellow fever vaccines within the Expanded Programme on Immunization schedule at 9 months. The administration of single fractional intradermal doses of IPV by needle and syringe or disposable-syringe jet injector compromises the immunity generated, although it results in a high post-vaccination poliovirus seroprevalence. FUNDING Bill & Melinda Gates Foundation.
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Omoleke SA, Mohammed I, Saidu Y. Ebola Viral Disease in West Africa: A Threat to Global Health, Economy and Political Stability. J Public Health Afr 2016; 7:534. [PMID: 28299152 PMCID: PMC5349256 DOI: 10.4081/jphia.2016.534] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 08/04/2016] [Accepted: 08/15/2016] [Indexed: 11/22/2022] Open
Abstract
The West African sub-continent is currently experiencing its first, and ironically, the largest and longest Ebola viral diseases (EVD) outbreak ever documented in modern medical history. The current outbreak is significant in several ways, including longevity, magnitude of morbidity and mortality, occurrence outside the traditional niches, rapid spread and potential of becoming a global health tragedy. The authors provided explicit insights into the current and historical background, drivers of the epidemic, societal impacts, status of vaccines and drugs development and proffered recommendations to halt and prevent future occurrences. The authors reviewed mainly five databases and a hand search of key relevant literature. We reviewed 51 articles that were relevant up until the 18th of August 2014. The authors supplemented the search with reference list of relevant articles and grey literature as well as relevant Internet websites. Article searches were limited to those published either in English or French. There are strong indications that the EVD may have been triggered by increased human activities and encroachment into the forest ecosystem spurred by increasing population and poverty-driven forest-dependent local economy. Containment efforts are being hampered by weak and fragile health systems, including public health surveillance and weak governance, certain socio-anthropological factors, fast travels (improved transport systems) and globalization. The societal impacts of the EBV outbreak are grave, including economic shutdown, weakening of socio-political systems, psychological distress, and unprecedented consumption of scarce health resources. The research and development (R&D) pipeline for product against EBV seems grossly insufficient. The outbreak of Ebola and the seeming difficulty to contain the epidemic is simply a reflection of the weak health system, poor surveillance and emergency preparedness/response, poverty and disconnect between the government and the people in many West African countries. Although interventions by the United Nations and other international development agencies could ultimately halt the epidemic, local communities must be engaged to build trust and create demand for the public health interventions being implemented in the Ebola-ravaged populations. In the intermediate and long term, post-Ebola rehabilitation should focus on strengthening of health systems, improving awareness about zoonosis and health behaviors, alleviating poverty and mitigating the impact of triggering factors. Finally, national governments and international development partners should mobilize huge resources and investments to spur or facilitate R&D of disease control tools for emerging and pernicious infectious diseases (not limited to EVD).
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Journal Article |
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Roca A, Afolabi MO, Saidu Y, Kampmann B. Ebola: a holistic approach is required to achieve effective management and control. J Allergy Clin Immunol 2015; 135:856-867. [PMID: 25843598 PMCID: PMC4382328 DOI: 10.1016/j.jaci.2015.02.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/12/2015] [Accepted: 02/17/2015] [Indexed: 01/07/2023]
Abstract
The current Ebola outbreak in West Africa has already caused substantial mortality and dire human and economic consequences. It continues to represent an alarming public health threat in the region and beyond and jeopardizes the provision of health care and other services in the affected countries. The scale of the epidemic has accelerated research efforts for diagnostics, treatment, and prevention galvanized through increased availability of funding. Our knowledge relating to the virus, disease pathogenesis, risk factors, dynamics of transmission, and epidemic control is increasing, and sociocultural factors have emerged as critical determinants for the success and failure of control efforts. However, there is a long way to go. In this review we summarize the current knowledge, examine the sociocultural context in West Africa, and outline priority areas for future research.
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Review |
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Foma MA, Saidu Y, Omoleke SA, Jafali J. Awareness of diabetes mellitus among diabetic patients in the Gambia: a strong case for health education and promotion. BMC Public Health 2013; 13:1124. [PMID: 24304618 PMCID: PMC3913398 DOI: 10.1186/1471-2458-13-1124] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 11/26/2013] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Awareness of various aspects of Diabetes Mellitus (DM) is essential for the prevention, management and control of the disease. However, several studies have consistently shown that awareness of DM in the general population is low. None of these studies, however, was conducted in The Gambia, even though the condition constitutes a major public health problem in the country. In this paper, we assessed the awareness of DM among diabetic patients attending the Medical Out-Patient Department (MOPD) of Royal Victoria Teaching Hospital (RVTH), Banjul. METHODS We interviewed 200 patients attending the MOPD of RVTH. We used a tool containing questions on patient's demographic characteristics and awareness of various aspects of DM including general knowledge on DM, causes, complications, management and prevention. RESULTS Of the 199 patients who were aware of their condition, only 47% said they knew what DM is. Similarly, 53% of the study participants had no knowledge of the causes of DM and about 50% were not aware of the methods of prevention. 67% knew that DM can result to loss of sight while 46.5% knew that DM can cause poor wound healing. Few respondents knew that DM can lead to kidney failure (13.5%), skin sepsis (12.0%), heart failure (5.5%) and stroke (4.5%). Close to 50% of the respondent did not know how DM can be prevented. Level of education, duration of illness and knowledge of a family member with diabetes were important predictors of knowledge in our study. CONCLUSION Our study shows that the majority of patients attending the MOPD have poor knowledge on several aspects of DM. Hence, there is need for conscious efforts towards improving the level of awareness through health education and promotion, not limited to the hospital but also within the general population, as part of strategies to prevent, manage and control DM.
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Odutola A, Ota MOC, Antonio M, Ogundare EO, Saidu Y, Owiafe PK, Worwui A, Idoko OT, Owolabi O, Kampmann B, Greenwood BM, Alderson M, Traskine M, Swinnen K, Verlant V, Dobbelaere K, Borys D. Immunogenicity of pneumococcal conjugate vaccine formulations containing pneumococcal proteins, and immunogenicity and reactogenicity of co-administered routine vaccines - A phase II, randomised, observer-blind study in Gambian infants. Vaccine 2019; 37:2586-2599. [PMID: 30975570 DOI: 10.1016/j.vaccine.2019.03.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 03/15/2019] [Accepted: 03/16/2019] [Indexed: 01/04/2023]
Abstract
BACKGROUND Two conserved pneumococcal proteins, pneumolysin toxoid (dPly) and pneumococcal histidine triad protein D (PhtD), combined with 10 polysaccharide conjugates from the pneumococcal non-typeable Haemophilus influenzae protein D-conjugate vaccine (PHiD-CV) in two investigational pneumococcal vaccine (PHiD-CV/dPly/PhtD) formulations were immunogenic and well-tolerated when administered to Gambian children. Here, we report immunogenicity of the polysaccharide conjugates, and immunogenicity and reactogenicity of co-administered routine vaccines. METHODS In this phase II, controlled, observer-blind, single-centre study, healthy infants aged 8-10 weeks were randomised (1:1:1:1:1:1) to six groups. Four groups received 3+0 schedule (2-3-4 months [M]) of PHiD-CV/dPly/PhtD (10 or 30 µg of each protein), PHiD-CV, or 13-valent pneumococcal conjugate vaccine; and two groups received 2+1 schedule (2-4-9 M) of PHiD-CV/dPly/PhtD (30 µg of each protein) or PHiD-CV. All infants received diphtheria-tetanus-whole cell pertussis-hepatitis B-Haemophilus influenzae type b (DTPw-HBV/Hib) and oral trivalent polio vaccines (OPV) at 2-3-4 M, and measles, yellow fever, and OPV vaccines at 9 M. We evaluated immune responses at 2-5-9-12 M; and reactogenicity 0-3 days post-vaccination. RESULTS 1200 infants were enrolled between June 2011 and May 2012; 1152 completed the study. 1 M post-primary vaccination, for each PHiD-CV serotype except 6B and 23F, ≥97.4% (3+0 schedule) and ≥96.4% (2+1 schedule) of infants had antibody concentrations ≥0.2 μg/mL. Immune responses were comparable between groups within the same vaccination schedules. Observed antibody geometric mean concentrations (GMCs) increased by 1 M post-primary vaccination compared to pre-vaccination. In the following months, GMCs and opsonophagocytic activity titres waned, with an increase post-booster for the 2+1 schedule. Immune responses to protein D and, DTPw-HBV/Hib, OPV, measles, and yellow fever vaccines were not altered by co-administration with pneumococcal proteins. Reactogenicity of co-administered vaccines was comparable between groups and did not raise concerns. CONCLUSION Immune responses to the 10 PHiD-CV polysaccharide conjugates and co-administered vaccines were not altered by addition of dPly and PhtD. ClinicalTrials.gov identifier NCT01262872.
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Research Support, Non-U.S. Gov't |
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Afolabi MO, Wariri O, Saidu Y, Otu A, Omoleke SA, Ebenso B, Adebiyi A, Ooko M, Ahinkorah BO, Ameyaw EK, Seidu AA, Agogo E, Nomhwange T, Salami K, Mohammed NI, Yaya S. Tracking the uptake and trajectory of COVID-19 vaccination coverage in 15 West African countries: an interim analysis. BMJ Glob Health 2021; 6:e007518. [PMID: 34906987 PMCID: PMC8718349 DOI: 10.1136/bmjgh-2021-007518] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 10/28/2021] [Indexed: 11/04/2022] Open
Abstract
The African Union Bureau of Heads of State and Government endorsed the COVID-19 Vaccine Development and Access Strategy to vaccinate at least 60% of each country's population with a safe and efficacious vaccine by 2022, to achieve the population-level immunity needed to bring the pandemic under control. Using publicly available, country-level population estimates and COVID-19 vaccination data, we provide unique insights into the uptake trends of COVID-19 vaccinations in the 15 countries that comprise the Economic Community of West Africa States (ECOWAS). Based on the vaccination rates in the ECOWAS region after three months of commencing COVID-19 vaccinations, we provide a projection of the trajectory and speed of vaccination needed to achieve a COVID-19 vaccination coverage rate of at least 60% of the total ECOWAS population. After three months of the deployment of COVID-19 vaccines across the ECOWAS countries, only 0.27% of the region's total population had been fully vaccinated. If ECOWAS countries follow this trajectory, the sub-region will have less than 1.6% of the total population fully vaccinated after 18 months of vaccine deployment. Our projection shows that to achieve a COVID-19 vaccination coverage of at least 60% of the total population in the ECOWAS sub-region after 9, 12 and 18 months of vaccine deployment; the speed of vaccination must be increased to 10, 7 and 4 times the current trajectory, respectively. West African governments must deploy contextually relevant and culturally acceptable strategies for COVID-19 vaccine procurements, distributions and implementations in order to achieve reasonable coverage and save lives, sooner rather than later.
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Review |
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Sabir AA, Bilbis LS, Saidu Y, Jimoh A, Iwuala SO, Isezuo SA, Kaoje AU, Abubakar SA. Oxidative stress among subjects with metabolic syndrome in Sokoto, North-Western Nigeria. Niger J Clin Pract 2016; 19:128-32. [DOI: 10.4103/1119-3077.173705] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Saidu Y, Vouking M, Njoh AA, Bachire HB, Tonga C, Mofor R, Bayiha C, Ewane L, Cornelius C, Mbida NDD, Abizou MB, Njie VM, Nzuobontane D. The effect of the ongoing civil strife on key immunisation outcomes in the North West and South West regions of Cameroon. Confl Health 2021; 15:8. [PMID: 33568157 PMCID: PMC7877013 DOI: 10.1186/s13031-021-00341-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 01/15/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Civil strife has long been recognized as a significant barrier in the fight against vaccine preventable diseases in several parts of the world. However, little is known about the impact of the ongoing civil strife on the immunisation system in the Northwest (NW) and Southwest (SW) regions of Cameroon, which erupted in late 2016. In this paper, we assessed the effect of the conflict on key immunisation outcomes in the North West and South West regions of Cameroon. METHODS Data were obtained from the standard EPI data reporting tool, the District Vaccine and Data Management Tool (DVDMT), from all the districts in the two regions. Completed forms were then reviewed for accuracy prior to data entry at central level. Summary statistics were used to estimate the variables of interest for each region for the years 2016 (pre-conflict) and 2019 (during conflict). RESULTS In the two regions, the security situation has deteriorated in almost all districts, which in turn has disrupted basic healthcare delivery in those areas. A total of 26 facilities were destroyed and 11 healthcare workers killed in both regions. Reported immunisation coverage rates for key antigens including, BCG, DPT-3 and MR, witnessed a dramatic decline between 2016 and 2019, ranging from 22% points decline for BCG in the NW and to 42% points decline for DPT-3 in the SW. Similarly, the proportion of districts with DPT-3 coverage of at least 80% dropped from 75% in 2016 to 11% in 2019 in the NW. In the SW this proportion dropped from 16% in 2016 to 0 % in 2019. CONCLUSION Our data demonstrates the marked negative impact of the ongoing civil strife on key immunisation outcomes in the two regions and the country at large. This decline could amplify the risk of vaccine preventable diseases vaccine preventable diseases outbreaks in the two regions. Besides the ongoing actions to contain the crises, effective strategies for reaching children in the conflict zones as well as the internally displaced population are needed. There is also the need to rebuild destroyed facilities as well as to protect health facilities and staff from targeted violence.
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Nde CJ, Raymond A, Saidu Y, Cheng NI, Nzuobontane D, Atemnkeng JT, Mbacham WF. Reaching Universal Health Coverage by 2035: Is Cameroon on Track? ACTA ACUST UNITED AC 2019. [DOI: 10.13189/ujph.2019.070304] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Onu A, Saidu Y, Ladan MJ, Bilbis LS, Aliero AA, Sahabi SM. Effect of Aqueous Stem Bark Extract of Khaya senegalensis on Some Biochemical, Haematological, and Histopathological Parameters of Rats. J Toxicol 2013; 2013:803835. [PMID: 24348549 PMCID: PMC3852576 DOI: 10.1155/2013/803835] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 09/19/2013] [Indexed: 11/23/2022] Open
Abstract
The subchronic effect of aqueous stem bark extract of Khaya senegalensis on some biochemical, haematological, and histopathological parameters of rats was investigated. The rats were divided into six groups of five rats per group. Groups I to VI were administered graded doses of 0, 400, 800, 1200, 1600, and 2000 mg/kg bw, respectively. The result of study revealed that administration of the Khaya senegalensis for twenty-eight days at the experimental dose resulted in significant (P < 0.05) increase in urea, electrolytes (Na(+), K(+)), and creatinine levels. The extract also significantly (P < 0.05) increased serum activity of ALT, AST, and ALP. The levels of protein, albumin, and bilirubin were significantly changed when compared to their control values, but they were not dose dependent. The hematological indices assayed in this study were not significantly affected at the experimental dose when compared to the control values. Histological studies of the liver showed cellular degeneration and necrosis and bile duct hyperplasia and fibrosis with lymphocytic infiltration of the hepatocyte, providing supportive evidence for discussing the biochemical findings, indicative of functional derangement. The histological architecture of the kidney and that of the heart were however preserved. The result of this study indicates that the aqueous stem bark extract of K. senegalensis may affect the cellular integrity of vital organs of the body.
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Idoko OT, Owolabi OA, Odutola AA, Ogundare O, Worwui A, Saidu Y, Smith-Sanneh A, Tunkara A, Sey G, Sanyang A, Mendy P, Ota MOC. Lessons in participant retention in the course of a randomized controlled clinical trial. BMC Res Notes 2014; 7:706. [PMID: 25298043 PMCID: PMC4200120 DOI: 10.1186/1756-0500-7-706] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Accepted: 09/26/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Clinical trials are increasingly being conducted as new products seek to enter the market. Deployment of such interventions is based on evidence obtained mainly from the gold standard of randomized controlled clinical trials (RCCT). A crucial factor in the ability of RCCTs to provide credible and generalisable data is sample size and retention of the required number of subjects at completion of the follow-up period. However, recruitment and retention in clinical trials are hindered by prevalent peculiar challenges in Africa that need to be circumvented. This article shares experiences from a phase II trial that recorded a high retention rate at 14 months follow-up at a new clinical trial site. METHODS Mothers bringing children less than two months of age to the health facility were given information and invited to have their child enrolled if the inclusion criteria were fulfilled. Participants were enrolled over 8 months. Trial procedures, duration and risks/benefits were painstakingly and sequentially explained to the communities, parents and relevant relatives before and during the trial period. The proportions of participants that completed or did not complete the trial were analyzed including the reasons for failure to complete all trial procedures. RESULTS 1044 individuals received information regarding the trial of which 371 returned for screening. 300 (81%) of them who fulfilled the inclusion criteria and did not meet any exclusion criteria were enrolled and 94% of these completed the trial. Consent withdrawal was the main reason for not completing the trial largely (75%) due to the father not being involved at the point of consenting or parents no longer being comfortable with blood sampling. CONCLUSIONS Participant retention in clinical trials remains a crucial factor in ensuring generalisability of trial data. Appropriate measures to enhance retention should include continuous community involvement in the process, adequate explanation of trial procedures and risks/benefits; and innovative tracing of participants adapted for the setting.
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Randomized Controlled Trial |
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Hassan S, Lawal M, Muhammad B, Umar R, Bilbis L, Saidu Y. Effects of Anthraquinone Glycosides and Aqueous Ethanol Extracts of Ficus sycomorus L. (Moraceae) on Rat Liver and Kidney Functions. ACTA ACUST UNITED AC 2007. [DOI: 10.3923/ajb.2007.136.141] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Njoh AA, Mboke E, Ndoula ST, Bachir HB, Nembot R, Chebo C, Aman A, Saidu Y. COVID-19 in a region of Cameroon hit by armed conflict. Pan Afr Med J 2022; 41:32. [PMID: 35382043 PMCID: PMC8956904 DOI: 10.11604/pamj.2022.41.32.32587] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 12/14/2021] [Indexed: 12/16/2022] Open
Abstract
INTRODUCTION the emergence of more transmissible SARS-CoV-2 variants like Delta and Omicron have triggered the next wave of COVID-19 in many parts of the world. Here we report a surge in COVID-19 cases and deaths in the Northwest (NW) Region of Cameroon, which is plagued with low immunization coverage and armed conflict. METHODS a cross-sectional study was conducted in September 2021 and data on COVID-19 cases and vaccination were reviewed from the Ministry of Health database from January 1st, 2020 to September 4th, 2021. The security situation of the region was obtained from the districts and regional health managers. Data were analyzed with MS Excel and results presented as trends and proportions. RESULTS since the onset of COVID-19 pandemic, there is an increasing prevalence in cases in the NW. Between epidemiological week 34-35 of 2021, there was a surge in COVID-19 cases in the NW. More than 70% of all COVID-19 related deaths reported in the country during epidemiological week-35 were recorded in this region. Despite this high mortality, COVID-19 vaccine uptake remains very low in the region. Indeed, just 0.6% of the 962,036-target population 18-years and above are fully immunized after 6-months of vaccination. CONCLUSION though the country´s epi-curve does not suggest a third wave currently, the NW is experiencing a steady COVID-19 case surge amid insecurity and the circulation of the Delta variant. There is therefore a need to adopt innovative strategies to improve immunization and strengthen other SARS-CoV-2 preventive measures in this region.
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Saidu Y, . ML, . SI, . RS, . DS, . LB. Partial Purification and Elucidation of Mechanism of Hypoglycaemic Agent of Aqueous Leaf Extract of Albizzia chevalieri Harms (Leguminosae). ACTA ACUST UNITED AC 2007. [DOI: 10.3923/jpt.2007.513.523] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Scotney S, Snidal S, Saidu Y, Ojumu A, Ngatia A, Bagana M, Mutuku F, Sobngwi J, Efe-Aluta O, Roper J, LeTallec Y, Kang'ethe A. Succeeding in New Vaccine Introduction: Lessons Learned From the Introduction of Inactivated Poliovirus Vaccine in Cameroon, Kenya, and Nigeria. J Infect Dis 2017; 216:S130-S136. [PMID: 28838156 PMCID: PMC5853243 DOI: 10.1093/infdis/jiw544] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Introducing a new vaccine is a large-scale endeavor that can face many challenges, resulting in introduction delays and inefficiencies. The development of national task teams and tools, such as prelaunch trackers, for the introduction of new vaccines (hereafter, "new vaccine introductions" [NVIs]) can help countries implement robust project management systems, front-load critical preparatory activities, and ensure continuous communication around vaccine supply and financing. In addition, implementing postlaunch assessments to take rapid corrective action accelerates the uptake of the new vaccines. NVIs can provide an opportunity to strengthen routine immunization, through strengthening program management systems or by reinforcing local immunization managers' abilities, among others. This article highlights key lessons learned during the introduction of inactivated poliovirus vaccine in 3 countries that would make future NVIs more successful. The article concludes by considering how the Immunization Systems Management Group of the Global Polio Eradication Initiative has been useful to the NVI process and how such global structures could be further enhanced.
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Bibby J, Saidu Y, Umesi A, Moneke-Anyanwoke N, Bashorun AO, Hydara MB, Adigweme I, Adetifa JU, Okoye M, Roberts E, Clemens R, Bandyopadhyay AS, Muhammad AK, Mulwa S, Royals M, Jarrahian C, Jeffries D, Kampmann B, Clarke E. The Immunogenicity of Fractional Intradermal Doses of the Inactivated Poliovirus Vaccine Is Associated With the Size of the Intradermal Fluid Bleb. Clin Infect Dis 2017; 65:851-854. [PMID: 28444156 PMCID: PMC5850454 DOI: 10.1093/cid/cix381] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 04/21/2017] [Indexed: 11/13/2022] Open
Abstract
The immunogenicity of fractional (one-fifth, 0.1 mL) intradermal doses of the inactivated poliovirus vaccine (ID fIPV) is positively correlated with the size of the intradermal fluid bleb. Training of vaccinators for campaign and routine ID fIPV administration should focus on generating an 8- to 10-mm bleb with each injection. Clinical Trials Registration NCT01847872.
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Saidu Y, Di Mattei P, Nchinjoh SC, Edwige NN, Nsah B, Muteh NJ, Ndoula ST, Abdullahi R, Zamir CS, Njoh AA, Adidja A, Ndiaye S, Wiwa O, Montomoli E, Clemens SAC. The Hidden Impact of the COVID-19 Pandemic on Routine Childhood Immunization Coverage in Cameroon. Vaccines (Basel) 2023; 11:645. [PMID: 36992229 PMCID: PMC10058217 DOI: 10.3390/vaccines11030645] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 02/16/2023] [Accepted: 02/27/2023] [Indexed: 03/15/2023] Open
Abstract
Background: The third round of the global pulse survey demonstrated that the abrupt and rapid progression of the COVID-19 pandemic significantly disrupted childhood immunization in many countries. Although Cameroon has reported over 120,000 COVID-19 cases, the reported national childhood vaccination coverage during the pandemic seems to have increased compared to that during the pre-COVID-19 period. Indeed, the first dose of the diphtheria, tetanus, and pertussis-containing vaccine (DTP-1) coverage increased from 85.4% in 2019 to 87.7% in 2020, and DTP-3 coverage increased from 79.5% in 2019 to 81.2% in 2020. The paucity of literature on the impact of COVID-19 on childhood vaccination in COVID-19 hotspot regions poses a challenge in developing a context-specific immunization recovery plan, hence the need to conduct this study. Methodology: We conducted a cross-sectional study using 2019 (pre-pandemic period) and 2020 (pandemic period) district childhood immunization data from the DHIS-2 database, weighted using completeness for each data entry against regional data completeness in 2020. Based on COVID-19 incidence, two hotspot regions were selected, with all districts (56/56) included in the final analysis. The Chi-square test was used to compare DTP-1 and DTP-3 coverage during the pre-pandemic and pandemic periods. Results: In the two hotspot regions, 8247 children missed DTP-1, and 12,896 children did not receive DTP-3 vaccines in the pandemic period compared to the results from the pre-pandemic period. Indeed, there was a significant drop in DTP-1 and DTP-3 coverage of 0.8% (p = 0.0002) and 3.1% (p = 0.0003), respectively, in the Littoral Region. Moreover, the Centre Region reported a 5.7% (p < 0.0001) and 7.6% (p < 0.0001) drop in DTP-1 and DTP-3 coverage, respectively. Most districts in the hotspot regions reported a decline in childhood immunization access (62.5%) and utilization (71.4%). Indeed, in the Littoral Region, 46% (11/24) and 58% (14/24) of districts experienced decreased vaccination access and utilization, respectively. Meanwhile, 75% (24/32) and 81% (26/32) of districts in the Centre Region experienced a drop in vaccination access and utilization, respectively. Conclusion: This study reported a situation where the national immunization indicators mask the impact of COVID-19 on childhood immunization in heavily hit regions. Therefore, this study presents valuable information for ensuring continuous vaccination service delivery during public health emergencies. The findings could also contribute to developing an immunization recovery plan and informing policy on future pandemic preparedness and response.
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Saidu Y, Angelis DD, Aiolli S, Gonnelli S, Georges AM. A Review of Regulatory Mechanisms Used by the WHO, EU, and US to Facilitate Access to Quality Medicinal Products in Developing Countries With Constrained Regulatory Capacities. Ther Innov Regul Sci 2013; 47:268-276. [PMID: 30227518 DOI: 10.1177/2168479012474281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Adequate medicine regulation requires nations to establish robust regulatory agencies that will subject all pharmaceutical products to pre- and postmarketing evaluation. These agencies are essential for any country wishing to ensure that the medicinal products it authorizes for use in its territory meet internationally agreed standards of safety, quality, and efficacy. Many developing nations, however, lack regulatory systems that can guarantee this set of requirements. As a result, almost all of these nations tend to rely on regulatory decisions made by well-resourced institutions, particularly the US Food and Drug Administration, the European Medicines Agency, and the World Health Organization. In this paper, the authors review the objectives, strengths, and weaknesses of some key regulatory initiatives instituted by these bodies to facilitate product registration in developing countries with constrained regulatory capacities.
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Habibullah S, Bilbis L, Ladan M, Ajagbonna O, Saidu Y. Aqueous Extract of Hibiscus sabdariffa Calyces Reduces Serum Triglycerides but Increases Serum and Egg Yolk Cholesterol of Shika Brown Laying Hens. ACTA ACUST UNITED AC 2006. [DOI: 10.3923/ajb.2007.42.49] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Njoh AA, Saidu Y, Bachir HB, Ndoula ST, Mboke E, Nembot R, Tambasho AC, Abizou MB, Seungue J, Mbanga C, Mbome VN. Impact of periodic intensification of routine immunization within an armed conflict setting and COVID-19 outbreak in Cameroon in 2020. Confl Health 2022; 16:29. [PMID: 35655226 PMCID: PMC9161648 DOI: 10.1186/s13031-022-00461-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 05/19/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Introduction
Cameroon’s Southwest Region (SW) has been hit by an armed conflict for over half a decade now, negatively affecting the region’s routine immunization and disease surveillance activities. This negative effect was further acerbated by the COVID-19 pandemic, which alongside the conflict, caused thousands of children to miss out on life-saving vaccinations. Herein, we present the contribution of periodic intensification of routine immunization in improving immunization and surveillance activities amid crises.
Method
Periodic intensification of routine immunization (PIRI) and disease surveillance were carried out in three rounds per health district. Before the intervention, the security profile of each district involved was reviewed. Data for this study was extracted on vaccination and surveillance activities from the District Health Information Software and monthly regional reports for 2019 and 2020 from the SW delegation of health.
Results
54,242 persons were vaccinated in the SW following these interventions. An increase in performance was observed in all 18 health districts in 2020 compared to 2019. Both DPT-HebB-Heb-3 vaccine and OPV-3 coverage rose by 28% points. Similarly, the proportion of health districts that investigated at least a case of acute flaccid paralysis increased by 83%, rising from just three districts in 2019 to all 18 in 2020.
Conclusion
PIRI was a practical approach to improving vaccination coverage and surveillance indicators in this region amidst the ongoing armed conflict and COVID-19 pandemic.
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Ross JC, Saidu Y, Nzuobontane D, Voukings MZ, Embrey SR. Application of the remaining vaccine vial monitor life calculation to field temperature monitoring data to improve visibility into cold chain equipment performance. Vaccine 2020; 38:7683-7687. [PMID: 33082013 DOI: 10.1016/j.vaccine.2020.09.078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 09/22/2020] [Accepted: 09/26/2020] [Indexed: 10/23/2022]
Abstract
Vaccine Vial Monitors (VVM) are used to estimate if a vaccine has been exposed to excessive hot temperatures. This endpoint measurement is useful in determining if a vaccine is safe to be administered to a patient, but it does not pinpoint where in the cold chain a vaccine was exposed to excessive heat. With the expansion and technological advancement of cold chain equipment temperature monitoring, it is now possible to remotely estimate VVM status as a vaccine moves through the cold chain. In the present study, we examine the application of the mathematical principles backing VVMs on real, continuous, temperature monitoring data in Africa. Results suggest that exposure to short bursts of hot temperature or long power outages may still allow for safe distribution of affected vaccines. The remaining VVM life calculation could improve managerial visibility into cold chain equipment performance allowing for better data-driven planning and maintenance decisions.
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Mapoko BSE, Frambo A, Saidu Y, Mbassi EDB, Atenguena E, Azemafac K, Kobayashi E, Tabola L, Nkeng G, Sango A, Maison AM, Noa SA, Ntama A, Mapenya RRM, Tayou R, Kouya F, Mbah G, Douanla P, Fonkwa C, Biwole ME, Sando Z, Sone AM, Ndom P. Assessment of barriers to optimal cancer control in adult cancer treatment centres in Cameroon. Ecancermedicalscience 2023; 17:1601. [PMID: 37799946 PMCID: PMC10550327 DOI: 10.3332/ecancer.2023.1601] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Indexed: 10/07/2023] Open
Abstract
Approximately 20,745 new cases of cancer were registered annually with 13,199 (64%) deaths in 2020 in Cameroon. Despite the increasing cancer burden, there is a paucity of reliable data that can enhance decision-making for cancer control in Cameroon. This assessment was, therefore, designed to generate data that may enable stakeholders, policymakers and funders to make data-driven decisions on cancer control. We conducted a cross-sectional survey in July 2020, which enabled us to collect data on key cancer variables from six adult cancer treatment centres in Cameroon. The key components of the assessment included case detection, service availability, human resource capacity, cost of chemotherapy and radiotherapy, the safety of chemotherapy sessions, data systems, patient education, palliative care, funding for chemotherapy and chemotherapy stock. Data were compiled and analysed using Microsoft Excel 2016. Data from four of the 6 sites show that 1,636 new cases were recorded representing an annual case detection rate of 11.8%. All the six assessed facilities offered chemotherapy services, 5/6 (83.3%) offered surgery for cancers, while just 1 (16.7%) offered radiotherapy services. In addition, none offered nuclear medicine services for cancer care and treatment. Similarly, none of the facilities had the WHO-recommended number of human resources for optimal cancer care. Overall, there were only 6 medical oncologists, 2 surgical oncologists, 3 radiation oncologists and 14 oncology nurses providing services across the 6 cancer treatment centres. Treatment services are expensive for an average national, with a complete course of chemotherapy followed by radiotherapy costing ~XAF 1,240,000 (~$2,480). None of the survey facilities had a recommended safe biosafety cabinet and clean room for the preparation of chemotherapies, rendering the preparation of chemotherapies suboptimal and hazardous. Data collection tools were manual, relatively available and very different across all the surveyed sites and the interval for data collection and transmission was collectively undefined. Optimal cancer care in adult cancer treatment centres is limited by several health systems and socio-economic factors. The identification of these barriers has enabled the formulation of action-oriented interventions, leveraging on the recently adopted national strategy for the prevention and control of cancers in the country.
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Mainasara A, Isa S, Dandare A, Ladan M, Saidu Y, Rabiu S. Blood pressure profile and insulin resistance in salt-induced hypertensive rats treated with camel milk. MEDITERRANEAN JOURNAL OF NUTRITION AND METABOLISM 2016. [DOI: 10.3233/mnm-160060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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