Journal Article > ResearchFull Text
PLOS One. 2014 December 8; Volume 9 (Issue 12); DOI:10.1371/journal.pone.0114702
Polonsky JA, Martinez-Pino I, Nackers F, Chonzi P, Manangazira P, et al.
PLOS One. 2014 December 8; Volume 9 (Issue 12); DOI:10.1371/journal.pone.0114702
Typhoid fever remains a significant public health problem in developing countries. In October 2011, a typhoid fever epidemic was declared in Harare, Zimbabwe - the fourth enteric infection epidemic since 2008. To orient control activities, we described the epidemiology and spatiotemporal clustering of the epidemic in Dzivaresekwa and Kuwadzana, the two most affected suburbs of Harare.
Journal Article > ResearchFull Text
Vaccine. 2022 June 9; Volume S0264-410X (Issue 22); 00552-7.; DOI:10.1016/j.vaccine.2022.04.093
Lightowler M, Manangazira P, Nackers F, Van Herp M, Phiri I, et al.
Vaccine. 2022 June 9; Volume S0264-410X (Issue 22); 00552-7.; DOI:10.1016/j.vaccine.2022.04.093
BACKGROUND
Zimbabwe suffers from regular outbreaks of typhoid fever (TF), worse since 2017. Most cases were in Harare and a vaccination campaign with Typhoid Conjugate Vaccine (TCV) was conducted in March 2019. The vaccine effectiveness (VE) was assessed against culture-confirmed S. Typhi in children six months to 15 years and in individuals six months to 45 years in Harare.
METHODS
A matched case-control study was conducted in three urban suburbs of Harare targeted by the TCV vaccination campaign. Suspected TF cases were enrolled prospectively in four health facilities and were matched to facility (1:1) and community (1:5) controls.
FINDINGS
Of 504 suspected cases from July 2019 to March 2020, 148 laboratory-confirmed TF cases and 153 controls confirmed-negative were identified. One hundred and five (47 aged six months to 15 years) cases were age, sex, and residence matched with 105 facility-based controls while 96 cases were matched 1:5 by age, sex, and immediate-neighbour with 229 community controls.
The adjusted VE against confirmed TF was 75% (95%CI: 1–94, p = 0.049) compared to facility controls, and 84% (95%CI: 57–94, p < 0.001) compared to community controls in individuals six months to 15 years. The adjusted VE against confirmed TF was 46% (95%CI: 26–77, p = 0.153) compared to facility controls, and 67% (95%CI: 35–83, p = 0.002) compared to community controls six months to 45 years old.
INTERPRETATION
This study confirms that one vaccine dose of TCV is effective to control TF in children between six months and 15 years old in an African setting.
Zimbabwe suffers from regular outbreaks of typhoid fever (TF), worse since 2017. Most cases were in Harare and a vaccination campaign with Typhoid Conjugate Vaccine (TCV) was conducted in March 2019. The vaccine effectiveness (VE) was assessed against culture-confirmed S. Typhi in children six months to 15 years and in individuals six months to 45 years in Harare.
METHODS
A matched case-control study was conducted in three urban suburbs of Harare targeted by the TCV vaccination campaign. Suspected TF cases were enrolled prospectively in four health facilities and were matched to facility (1:1) and community (1:5) controls.
FINDINGS
Of 504 suspected cases from July 2019 to March 2020, 148 laboratory-confirmed TF cases and 153 controls confirmed-negative were identified. One hundred and five (47 aged six months to 15 years) cases were age, sex, and residence matched with 105 facility-based controls while 96 cases were matched 1:5 by age, sex, and immediate-neighbour with 229 community controls.
The adjusted VE against confirmed TF was 75% (95%CI: 1–94, p = 0.049) compared to facility controls, and 84% (95%CI: 57–94, p < 0.001) compared to community controls in individuals six months to 15 years. The adjusted VE against confirmed TF was 46% (95%CI: 26–77, p = 0.153) compared to facility controls, and 67% (95%CI: 35–83, p = 0.002) compared to community controls six months to 45 years old.
INTERPRETATION
This study confirms that one vaccine dose of TCV is effective to control TF in children between six months and 15 years old in an African setting.
Journal Article > ResearchFull Text
Vaccine. 2022 August 2; Volume 12; 100201.; DOI:10.1016/j.jvacx.2022.100201
Poncin M, Marembo J, Chitando P, Sreenivasan N, Makwara I, et al.
Vaccine. 2022 August 2; Volume 12; 100201.; DOI:10.1016/j.jvacx.2022.100201
INTRODUCTION
Typhoid fever is a public-health problem in Harare, the capital city of Zimbabwe, with seasonal outbreaks occurring annually since 2010. In 2019, the Ministry of Health and Child Care (MOHCC) organized the first typhoid conjugate vaccination campaign in Africa in response to a recurring typhoid outbreak in a large urban setting.
METHODS
As part of a larger public health response to a typhoid fever outbreak in Harare, Gavi approved in September 2018 a MOHCC request for 340,000 doses of recently prequalified Typbar-TCV to implement a mass vaccination campaign. To select areas for the campaign, typhoid fever surveillance data from January 2016 until June 2018 was reviewed. We collected and analyzed information from the MOHCC and its partners to describe the vaccination campaign planning, implementation, feasibility, administrative coverage and financial costs.
RESULTS
The campaign was conducted in nine high-density suburbs of Harare over eight days in February-March 2019 and targeted all children aged 6 months-15 years; however, the target age range was extended up to 45 years in one suburb due to the past high attack rate among adults. A total of 318,698 people were vaccinated, resulting in overall administrative coverage of 85.4 percent. More than 750 community volunteers and personnel from the MOHCC and the Ministry of Education were trained and involved in social mobilization and vaccination activities. The MOHCC used a combination of vaccination strategies (i.e., fixed and mobile immunization sites, a creche and school-based strategy, and door-to-door activities). Financial costs were estimated at US$ 2.39 per dose, including the vaccine and vaccination supplies (US$ 0.79 operational costs per dose excluding vaccine and vaccination supplies).
CONCLUSIONS
A mass targeted campaign in densely populated urban areas in Harare, using the recently prequalified typhoid conjugate vaccine, was feasible and achieved a high overall coverage in a short period of time.
Typhoid fever is a public-health problem in Harare, the capital city of Zimbabwe, with seasonal outbreaks occurring annually since 2010. In 2019, the Ministry of Health and Child Care (MOHCC) organized the first typhoid conjugate vaccination campaign in Africa in response to a recurring typhoid outbreak in a large urban setting.
METHODS
As part of a larger public health response to a typhoid fever outbreak in Harare, Gavi approved in September 2018 a MOHCC request for 340,000 doses of recently prequalified Typbar-TCV to implement a mass vaccination campaign. To select areas for the campaign, typhoid fever surveillance data from January 2016 until June 2018 was reviewed. We collected and analyzed information from the MOHCC and its partners to describe the vaccination campaign planning, implementation, feasibility, administrative coverage and financial costs.
RESULTS
The campaign was conducted in nine high-density suburbs of Harare over eight days in February-March 2019 and targeted all children aged 6 months-15 years; however, the target age range was extended up to 45 years in one suburb due to the past high attack rate among adults. A total of 318,698 people were vaccinated, resulting in overall administrative coverage of 85.4 percent. More than 750 community volunteers and personnel from the MOHCC and the Ministry of Education were trained and involved in social mobilization and vaccination activities. The MOHCC used a combination of vaccination strategies (i.e., fixed and mobile immunization sites, a creche and school-based strategy, and door-to-door activities). Financial costs were estimated at US$ 2.39 per dose, including the vaccine and vaccination supplies (US$ 0.79 operational costs per dose excluding vaccine and vaccination supplies).
CONCLUSIONS
A mass targeted campaign in densely populated urban areas in Harare, using the recently prequalified typhoid conjugate vaccine, was feasible and achieved a high overall coverage in a short period of time.
Conference Material > Abstract
Ronoh Y, Some D, Ortuno R, Kuwenyi K, Mupepe T, et al.
MSF Scientific Days International 2020: Research. 2020 May 20
INTRODUCTION
Cervical cancer is now largely a preventable disease; however, implementation of highly sensitive molecular screening technologies in low-resource settings is partly hindered by the need for intensive investment in equipment and highly trained, skilled laboratory personnel. Resource limitations often preclude the possibility of same-day screening and treatment, as recommend by WHO. We sought to assess the diagnostic accuracy of self-collected versus nurse-collected high vaginal samples (HVS) for human papillomavirus (HPV) screening using GeneXpert, for within-country validation and to further inform its scale-up within routine point-of-care testing in primary healthcare systems.
METHODS
Consenting women presenting for routine cervical screening in selected health facilities in Gutu District, Zimbabwe, were asked to provide three HVS obtained at the same time on a single visit; the first, self-collected, and the following two, nurse-collected. Nurse-collected HVS were tested with GeneXpert (Cepheid, Sunnyvale, USA) and Cobas HPV (Roche, Pleasanton, USA; used as the reference test), whilst self-collected HVS were tested only using GeneXpert. Those testing positive on the reference test were offered visual inspection with acetic acid and cervicography (VIAC). Women with a positive VIAC examination were offered cryotherapy or loop electrosurgical excision procedure.
ETHICS
This study was approved by the MSF Ethics Review Board.
RESULTS
279 participants consented to provide HVS; none reported discomfort or side effects during or after swabbing. Among nurse-collected HVS, 11/279 participants were found positive on genotyping for HPV-16 using Cobas HPV, and nine of 279 were positive using GeneXpert. Eight out of 279 were identified on genotyping for HPV-18/45 using both platforms. The sensitivities of testing for HPV-16 and 18/45 using GeneXpert as compared to the reference test, Cobas, were 89% (95%CI 53-100) and 63% (95%CI 25-92) respectively. The sensitivity of self- and nurse-collected HVS for HPV-16 tested using GeneXpert, as compared to the reference test, was 89% (eight of nine; 95%CI 52-100). Specificity was 100% (95%CI 97-100), with a positive predictive value of 89% (95%CI 52-100), and negative predictive value of 100% (95%CI 97-100). However, sensitivity for detection of HPV-18/45 was 68.3% (95%CI 34-100).
CONCLUSION
Performance of cervical cancer screening using self-collected HVS tested with GeneXpert is comparable to that with nurse-collected HVS. Integrated GeneXpert platforms are already in wide use, enabling rapid diagnosis of tuberculosis, detection of HIV viral load, and early infant diagnosis of HIV, using a single piece of equipment. Deploying GeneXpert for HPV screening using self-collected HVS could help to provide timely results, especially in settings where VIAC is unavailable.
Cervical cancer is now largely a preventable disease; however, implementation of highly sensitive molecular screening technologies in low-resource settings is partly hindered by the need for intensive investment in equipment and highly trained, skilled laboratory personnel. Resource limitations often preclude the possibility of same-day screening and treatment, as recommend by WHO. We sought to assess the diagnostic accuracy of self-collected versus nurse-collected high vaginal samples (HVS) for human papillomavirus (HPV) screening using GeneXpert, for within-country validation and to further inform its scale-up within routine point-of-care testing in primary healthcare systems.
METHODS
Consenting women presenting for routine cervical screening in selected health facilities in Gutu District, Zimbabwe, were asked to provide three HVS obtained at the same time on a single visit; the first, self-collected, and the following two, nurse-collected. Nurse-collected HVS were tested with GeneXpert (Cepheid, Sunnyvale, USA) and Cobas HPV (Roche, Pleasanton, USA; used as the reference test), whilst self-collected HVS were tested only using GeneXpert. Those testing positive on the reference test were offered visual inspection with acetic acid and cervicography (VIAC). Women with a positive VIAC examination were offered cryotherapy or loop electrosurgical excision procedure.
ETHICS
This study was approved by the MSF Ethics Review Board.
RESULTS
279 participants consented to provide HVS; none reported discomfort or side effects during or after swabbing. Among nurse-collected HVS, 11/279 participants were found positive on genotyping for HPV-16 using Cobas HPV, and nine of 279 were positive using GeneXpert. Eight out of 279 were identified on genotyping for HPV-18/45 using both platforms. The sensitivities of testing for HPV-16 and 18/45 using GeneXpert as compared to the reference test, Cobas, were 89% (95%CI 53-100) and 63% (95%CI 25-92) respectively. The sensitivity of self- and nurse-collected HVS for HPV-16 tested using GeneXpert, as compared to the reference test, was 89% (eight of nine; 95%CI 52-100). Specificity was 100% (95%CI 97-100), with a positive predictive value of 89% (95%CI 52-100), and negative predictive value of 100% (95%CI 97-100). However, sensitivity for detection of HPV-18/45 was 68.3% (95%CI 34-100).
CONCLUSION
Performance of cervical cancer screening using self-collected HVS tested with GeneXpert is comparable to that with nurse-collected HVS. Integrated GeneXpert platforms are already in wide use, enabling rapid diagnosis of tuberculosis, detection of HIV viral load, and early infant diagnosis of HIV, using a single piece of equipment. Deploying GeneXpert for HPV screening using self-collected HVS could help to provide timely results, especially in settings where VIAC is unavailable.
Journal Article > CommentaryFull Text
Morbidity and Mortality Weekly Report. 2018 May 18; Volume 67 (Issue 19); 560-561.; DOI:10.15585/mmwr.mm6719a6
McAteer JB, Danda S, Nhende T, Manamike P, Parayiwa T, et al.
Morbidity and Mortality Weekly Report. 2018 May 18; Volume 67 (Issue 19); 560-561.; DOI:10.15585/mmwr.mm6719a6
Journal Article > ReviewAbstract Only
J Antimicrob Chemother. 2020 December 21; Volume 76 (Issue 5); 1160-1167.; DOI:10.1093/jac/dkaa519
Mashe T, Leekitcharoenphon P, Mtapuri-Zinyowera S, Kingsley RA, Robertson V, et al.
J Antimicrob Chemother. 2020 December 21; Volume 76 (Issue 5); 1160-1167.; DOI:10.1093/jac/dkaa519
BACKGROUND
Typhoid fever, caused by S. enterica ser. Typhi, continues to be a substantial health burden in developing countries. Little is known of the genotypic diversity of S. enterica ser. Typhi in Zimbabwe, but this is key for understanding the emergence and spread of this pathogen and devising interventions for its control.
OBJECTIVES
To report the molecular epidemiology of S. enterica ser. Typhi outbreak strains circulating from 2012 to 2019 in Zimbabwe, using comparative genomics.
METHODS
A review of typhoid cases records from 2012 to 2019 in Zimbabwe was performed. The phylogenetic relationship of outbreak isolates from 2012 to 2019 and emergence of antibiotic resistance was investigated by whole-genome sequence analysis.
RESULTS
A total 22 479 suspected typhoid cases, 760 confirmed cases were reported from 2012 to 2019 and 29 isolates were sequenced. The majority of the sequenced isolates were predicted to confer resistance to aminoglycosides, β-lactams, phenicols, sulphonamides, tetracycline and fluoroquinolones (including qnrS detection). The qnrS1 gene was associated with an IncN (subtype PST3) plasmid in 79% of the isolates. Whole-genome SNP analysis, SNP-based haplotyping and resistance determinant analysis showed that 93% of the isolates belonged to a single clade represented by multidrug-resistant H58 lineage I (4.3.1.1), with a maximum pair-wise distance of 22 SNPs.
CONCLUSIONS
This study has provided detailed genotypic characterization of the outbreak strain, identified as S. Typhi 4.3.1.1 (H58). The strain has reduced susceptibility to ciprofloxacin due to qnrS carried by an IncN (subtype PST3) plasmid resulting from ongoing evolution to full resistance.
Typhoid fever, caused by S. enterica ser. Typhi, continues to be a substantial health burden in developing countries. Little is known of the genotypic diversity of S. enterica ser. Typhi in Zimbabwe, but this is key for understanding the emergence and spread of this pathogen and devising interventions for its control.
OBJECTIVES
To report the molecular epidemiology of S. enterica ser. Typhi outbreak strains circulating from 2012 to 2019 in Zimbabwe, using comparative genomics.
METHODS
A review of typhoid cases records from 2012 to 2019 in Zimbabwe was performed. The phylogenetic relationship of outbreak isolates from 2012 to 2019 and emergence of antibiotic resistance was investigated by whole-genome sequence analysis.
RESULTS
A total 22 479 suspected typhoid cases, 760 confirmed cases were reported from 2012 to 2019 and 29 isolates were sequenced. The majority of the sequenced isolates were predicted to confer resistance to aminoglycosides, β-lactams, phenicols, sulphonamides, tetracycline and fluoroquinolones (including qnrS detection). The qnrS1 gene was associated with an IncN (subtype PST3) plasmid in 79% of the isolates. Whole-genome SNP analysis, SNP-based haplotyping and resistance determinant analysis showed that 93% of the isolates belonged to a single clade represented by multidrug-resistant H58 lineage I (4.3.1.1), with a maximum pair-wise distance of 22 SNPs.
CONCLUSIONS
This study has provided detailed genotypic characterization of the outbreak strain, identified as S. Typhi 4.3.1.1 (H58). The strain has reduced susceptibility to ciprofloxacin due to qnrS carried by an IncN (subtype PST3) plasmid resulting from ongoing evolution to full resistance.
Conference Material > Poster
Ngwa W, Manangazira P, Some D, Ortuno R, Ronoh Y, et al.
MSF Scientific Days International 2021: Research. 2021 May 18
Conference Material > Slide Presentation
Ronoh Y, Some D, Ortuno R, Kuwenyi K, Mupepe T, et al.
MSF Scientific Days International 2020: Research. 2020 May 13
Other > Pre-Print
medRxiv. 2022 March 31; DOI:10.1101/2022.03.28.22273032
Lightowler M, Manangazira P, Nackers F, Van Herp M, Phiri I, et al.
medRxiv. 2022 March 31; DOI:10.1101/2022.03.28.22273032
BACKGROUND
Zimbabwe suffers from regular outbreaks of typhoid fever (TF), worse since 2017. Most cases were in Harare and a vaccination campaign with Typhoid Conjugate Vaccine (TCV) was conducted in March 2019. The vaccine effectiveness (VE) was assessed against culture-confirmed S. Typhi in children six months to 15 years and in individuals six months to 45 years in Harare.
METHODS
A matched case-control study was conducted in three urban suburbs of Harare targeted by the TCV vaccination campaign. Suspected TF cases were enrolled prospectively in four health facilities and were matched to facility (1:1) and community (1:5) controls.
FINDINGS
Of 504 suspected cases from July 2019 to March 2020, 148 laboratory-confirmed TF cases and 153 controls confirmed-negative were identified. One hundred and five (47 aged six months to 15 years) cases were age, sex, and residence matched with 105 facility-based controls while 96 cases were matched 1:5 by age, sex, and immediate-neighbour with 229 community controls.
The adjusted VE against confirmed TF was 75% (95%CI: 1–94, p=0.049) compared to facility controls, and 84% (95%CI: 57–94, p<0.001) compared to community controls in individuals six months to 15 years. The adjusted VE against confirmed TF was 46% (95%CI: 26–77, p=0.153) compared to facility controls, and 67% (95%CI: 35–83, p=0.002) compared to community controls six months to 45 years old.
INTERPRETATION
This study confirms that one vaccine dose of TCV is effective to control TF in children between six months and 15 years old in an African setting.
Zimbabwe suffers from regular outbreaks of typhoid fever (TF), worse since 2017. Most cases were in Harare and a vaccination campaign with Typhoid Conjugate Vaccine (TCV) was conducted in March 2019. The vaccine effectiveness (VE) was assessed against culture-confirmed S. Typhi in children six months to 15 years and in individuals six months to 45 years in Harare.
METHODS
A matched case-control study was conducted in three urban suburbs of Harare targeted by the TCV vaccination campaign. Suspected TF cases were enrolled prospectively in four health facilities and were matched to facility (1:1) and community (1:5) controls.
FINDINGS
Of 504 suspected cases from July 2019 to March 2020, 148 laboratory-confirmed TF cases and 153 controls confirmed-negative were identified. One hundred and five (47 aged six months to 15 years) cases were age, sex, and residence matched with 105 facility-based controls while 96 cases were matched 1:5 by age, sex, and immediate-neighbour with 229 community controls.
The adjusted VE against confirmed TF was 75% (95%CI: 1–94, p=0.049) compared to facility controls, and 84% (95%CI: 57–94, p<0.001) compared to community controls in individuals six months to 15 years. The adjusted VE against confirmed TF was 46% (95%CI: 26–77, p=0.153) compared to facility controls, and 67% (95%CI: 35–83, p=0.002) compared to community controls six months to 45 years old.
INTERPRETATION
This study confirms that one vaccine dose of TCV is effective to control TF in children between six months and 15 years old in an African setting.