Journal Article > ResearchFull Text
Lancet. 2018 May 1; Volume 391 (Issue 10133); DOI:10.1016/S0140-6736(17)33050-7
Lessler J, Moore SM, Luquero FJ, McKay H, Grais RF, et al.
Lancet. 2018 May 1; Volume 391 (Issue 10133); DOI:10.1016/S0140-6736(17)33050-7
Cholera remains a persistent health problem in sub-Saharan Africa and worldwide. Cholera can be controlled through appropriate water and sanitation, or by oral cholera vaccination, which provides transient (∼3 years) protection, although vaccine supplies remain scarce. We aimed to map cholera burden in sub-Saharan Africa and assess how geographical targeting could lead to more efficient interventions.
Journal Article > ResearchFull Text
Bull World Health Organ. 2018 September 27; Volume 96 (Issue 12); 817-825.; DOI:10.2471/BLT.17.206417
Grandesso F, Rafael F, Chipeta S, Alley I, Saussier C, et al.
Bull World Health Organ. 2018 September 27; Volume 96 (Issue 12); 817-825.; DOI:10.2471/BLT.17.206417
OBJECTIVE
To evaluate vaccination coverage, identify reasons for non-vaccination and assess satisfaction with two innovative strategies for distributing second doses in an oral cholera vaccine campaign in 2016 in Lake Chilwa, Malawi, in response to a cholera outbreak.
METHODS
We performed a two-stage cluster survey. The population interviewed was divided in three strata according to the second-dose vaccine distribution strategy: (i) a standard strategy in 1477 individuals (68 clusters of 5 households) on the lake shores; (ii) a simplified cold-chain strategy in 1153 individuals (59 clusters of 5 households) on islands in the lake; and (iii) an out-of-cold-chain strategy in 295 fishermen (46 clusters of 5 to 15 fishermen) in floating homes, called zimboweras.
FINDING
Vaccination coverage with at least one dose was 79.5% (1153/1451) on the lake shores, 99.3% (1098/1106) on the islands and 84.7% (200/236) on zimboweras. Coverage with two doses was 53.0% (769/1451), 91.1% (1010/1106) and 78.8% (186/236), in the three strata, respectively. The most common reason for non-vaccination was absence from home during the campaign. Most interviewees liked the novel distribution strategies.
CONCLUSION
Vaccination coverage on the shores of Lake Chilwa was moderately high and the innovative distribution strategies tailored to people living on the lake provided adequate coverage, even among hard-to-reach communities. Community engagement and simplified delivery procedures were critical for success. Off-label, out-of-cold-chain administration of oral cholera vaccine should be considered as an effective strategy for achieving high coverage in hard-to-reach communities. Nevertheless, coverage and effectiveness must be monitored over the short and long term.
To evaluate vaccination coverage, identify reasons for non-vaccination and assess satisfaction with two innovative strategies for distributing second doses in an oral cholera vaccine campaign in 2016 in Lake Chilwa, Malawi, in response to a cholera outbreak.
METHODS
We performed a two-stage cluster survey. The population interviewed was divided in three strata according to the second-dose vaccine distribution strategy: (i) a standard strategy in 1477 individuals (68 clusters of 5 households) on the lake shores; (ii) a simplified cold-chain strategy in 1153 individuals (59 clusters of 5 households) on islands in the lake; and (iii) an out-of-cold-chain strategy in 295 fishermen (46 clusters of 5 to 15 fishermen) in floating homes, called zimboweras.
FINDING
Vaccination coverage with at least one dose was 79.5% (1153/1451) on the lake shores, 99.3% (1098/1106) on the islands and 84.7% (200/236) on zimboweras. Coverage with two doses was 53.0% (769/1451), 91.1% (1010/1106) and 78.8% (186/236), in the three strata, respectively. The most common reason for non-vaccination was absence from home during the campaign. Most interviewees liked the novel distribution strategies.
CONCLUSION
Vaccination coverage on the shores of Lake Chilwa was moderately high and the innovative distribution strategies tailored to people living on the lake provided adequate coverage, even among hard-to-reach communities. Community engagement and simplified delivery procedures were critical for success. Off-label, out-of-cold-chain administration of oral cholera vaccine should be considered as an effective strategy for achieving high coverage in hard-to-reach communities. Nevertheless, coverage and effectiveness must be monitored over the short and long term.
Journal Article > ResearchAbstract Only
Science. 2017 November 10; Volume 358 (Issue 6364); 785-789.; DOI:10.1126/science.aad5901
Weill FX, Domman D, Njamkepo E, Tarr C, Rauzier J, et al.
Science. 2017 November 10; Volume 358 (Issue 6364); 785-789.; DOI:10.1126/science.aad5901
The seventh cholera pandemic has heavily affected Africa, although the origin and continental spread of the disease remain undefined. We used genomic data from 1070 Vibrio cholerae O1 isolates, across 45 African countries and over a 49-year period, to show that past epidemics were attributable to a single expanded lineage. This lineage was introduced at least 11 times since 1970, into two main regions, West Africa and East/Southern Africa, causing epidemics that lasted up to 28 years. The last five introductions into Africa, all from Asia, involved multidrug-resistant sublineages that replaced antibiotic-susceptible sublineages after 2000. This phylogenetic framework describes the periodicity of lineage introduction and the stable routes of cholera spread, which should inform the rational design of control measures for cholera in Africa.
Journal Article > ResearchFull Text
N Engl J Med. 2014 May 29; Volume 370 (Issue 22); 2111-2120.; DOI:10.1056/NEJMoa1312680
Luquero FJ, Grout L, Ciglenecki I, Sakoba K, Traore B, et al.
N Engl J Med. 2014 May 29; Volume 370 (Issue 22); 2111-2120.; DOI:10.1056/NEJMoa1312680
BACKGROUND
The use of vaccines to prevent and control cholera is currently under debate. Shanchol is one of the two oral cholera vaccines prequalified by the World Health Organization; however, its effectiveness under field conditions and the protection it confers in the first months after administration remain unknown. The main objective of this study was to estimate the short-term effectiveness of two doses of Shanchol used as a part of the integrated response to a cholera outbreak in Africa.
METHODS
We conducted a matched case-control study in Guinea between May 20 and October 19, 2012. Suspected cholera cases were confirmed by means of a rapid test, and controls were selected among neighbors of the same age and sex as the case patients. The odds of vaccination were compared between case patients and controls in bivariate and adjusted conditional logistic-regression models. Vaccine effectiveness was calculated as (1-odds ratio)×100.
RESULTS
Between June 8 and October 19, 2012, we enrolled 40 case patients and 160 controls in the study for the primary analysis. After adjustment for potentially confounding variables, vaccination with two complete doses was associated with significant protection against cholera (effectiveness, 86.6%; 95% confidence interval, 56.7 to 95.8; P=0.001).
CONCLUSIONS
In this study, Shanchol was effective when used in response to a cholera outbreak in Guinea. This study provides evidence supporting the addition of vaccination as part of the response to an outbreak. It also supports the ongoing efforts to establish a cholera vaccine stockpile for emergency use, which would enhance outbreak prevention and control strategies. (Funded by Médecins sans Frontières.).
The use of vaccines to prevent and control cholera is currently under debate. Shanchol is one of the two oral cholera vaccines prequalified by the World Health Organization; however, its effectiveness under field conditions and the protection it confers in the first months after administration remain unknown. The main objective of this study was to estimate the short-term effectiveness of two doses of Shanchol used as a part of the integrated response to a cholera outbreak in Africa.
METHODS
We conducted a matched case-control study in Guinea between May 20 and October 19, 2012. Suspected cholera cases were confirmed by means of a rapid test, and controls were selected among neighbors of the same age and sex as the case patients. The odds of vaccination were compared between case patients and controls in bivariate and adjusted conditional logistic-regression models. Vaccine effectiveness was calculated as (1-odds ratio)×100.
RESULTS
Between June 8 and October 19, 2012, we enrolled 40 case patients and 160 controls in the study for the primary analysis. After adjustment for potentially confounding variables, vaccination with two complete doses was associated with significant protection against cholera (effectiveness, 86.6%; 95% confidence interval, 56.7 to 95.8; P=0.001).
CONCLUSIONS
In this study, Shanchol was effective when used in response to a cholera outbreak in Guinea. This study provides evidence supporting the addition of vaccination as part of the response to an outbreak. It also supports the ongoing efforts to establish a cholera vaccine stockpile for emergency use, which would enhance outbreak prevention and control strategies. (Funded by Médecins sans Frontières.).
Journal Article > ResearchFull Text
Vaccine. 2019 September 10; Volume 38 Suppl 1; A132-A140.; DOI:10.1016/j.vaccine.2019.08.086
Pezzoli L, Cavailler P, Mengel M, Matzger H, Lorenson T, et al.
Vaccine. 2019 September 10; Volume 38 Suppl 1; A132-A140.; DOI:10.1016/j.vaccine.2019.08.086
Vaccination is a key intervention to prevent and control cholera in conjunction with water, sanitation and hygiene activities. An oral cholera vaccine (OCV) stockpile was established by the World Health Organization (WHO) in 2013. We reviewed its use from July 2013 to all of 2018 in order to assess its role in cholera control. We computed information related to OCV deployments and campaigns conducted including setting, target population, timelines, delivery strategy, reported adverse events, coverage achieved, and costs. In 2013–2018, a total of 83,509,941 OCV doses have been requested by 24 countries, of which 55,409,160 were approved and 36,066,010 eventually shipped in 83 deployments, resulting in 104 vaccination campaigns in 22 countries. OCVs had in general high uptake (mean administrative coverage 1st dose campaign at 90.3%; 2nd dose campaign at 88.2%; mean survey-estimated two-dose coverage at 69.9%, at least one dose at 84.6%) No serious adverse events were reported. Campaigns were organized quickly (five days median duration). In emergency settings, the longest delay was from the occurrence of the emergency to requesting OCV (median: 26 days). The mean cost of administering one dose of vaccine was 2.98 USD. The OCV stockpile is an important public health resource. OCVs were generally well accepted by the population and their use demonstrated to be safe and feasible in all settings. OCV was an inexpensive intervention, although timing was a limiting factor for emergency use. The dynamic created by the establishment of the OCV stockpile has played a role in the increased use of the vaccine by setting in motion a virtuous cycle by which better monitoring and evaluation leads to better campaign organization, better cholera control, and more requests being generated. Further work is needed to improve timeliness of response and contextualize strategies for OCV delivery in the various settings.
Journal Article > ResearchFull Text
PLOS Med. 2013 September 10; Volume 10 (Issue 9); 1001512.; DOI:10.1371/journal.pmed.1001512
Ciglenecki I, Sakoba K, Luquero FJ, Heile M, Itama C, et al.
PLOS Med. 2013 September 10; Volume 10 (Issue 9); 1001512.; DOI:10.1371/journal.pmed.1001512
• Oral cholera vaccines are safe and effective, and in 2010 were added to WHO recommendations for cholera outbreak control. However, doubts about feasibility, timeliness, and acceptability by the population, and the fear of diverting resources from other preventive interventions, have discouraged their use during epidemics.
• We report on the first large-scale use of oral cholera vaccine as an outbreak control measure in Africa; this was also the first time Shanchol vaccine was used in Africa.
• We administered 312,650 doses of vaccine during two vaccination rounds in two coastal districts in Guinea. The feasibility, timeliness of implementation, and delivery cost were similar to those of other mass vaccination campaigns.
• The campaign was well accepted by the population, and high vaccination coverage was achieved despite the short time available for preparation, the two-dose schedule, the remote rural setting, and the highly mobile population.
• Oral cholera vaccines are a promising new tool in the arsenal of cholera control measures, alongside efforts to improve provision of safe water and sanitation.
• We report on the first large-scale use of oral cholera vaccine as an outbreak control measure in Africa; this was also the first time Shanchol vaccine was used in Africa.
• We administered 312,650 doses of vaccine during two vaccination rounds in two coastal districts in Guinea. The feasibility, timeliness of implementation, and delivery cost were similar to those of other mass vaccination campaigns.
• The campaign was well accepted by the population, and high vaccination coverage was achieved despite the short time available for preparation, the two-dose schedule, the remote rural setting, and the highly mobile population.
• Oral cholera vaccines are a promising new tool in the arsenal of cholera control measures, alongside efforts to improve provision of safe water and sanitation.