• Evaluation of the stability of measles vaccine out of the cold chain under extended controlled temperature conditions.

      Juan-Giner, A; Alsalhani, A; Panunzi, I; Lambert, V; Van Herp, M; Gairola, S (Elsevier, 2020-02-08)
      Measles outbreaks occur periodically in remote and difficult to reach areas in countries such as the Democratic Republic of Congo. The possibility to keep measles vaccines at temperatures outside the cold chain for a limited period prior to administration would be an advantage for organizations such as Médecins Sans Frontières, which repeatedly respond to measles outbreaks in difficult contexts. Using stability data at 37 °C and 40 °C provided by Serum Institute of India Private Limited we applied the product release model for Extended Controlled Temperature Conditions (ECTC) to evaluate the possibility of an out of the cold chain excursion. Measles vaccine in the lyophilized form remains above the minimum required potency at the end of the shelf-life for up to 6 days at 37 °C or for 2 days at 40 °C. This evaluation supports the use of a monodose presentation of measles vaccine in ECTC. This could be an advantage for outbreak response in isolated and difficult to reach areas. However the operational advantages of this approach need to be established.
    • Field challenges to measles elimination in the Democratic Republic of the Congo

      Coulborn, RM; Nackers, F; Bachy, C; Porten, K; Vochten, H; Ndele, E; Van Herp, M; Bibala-Faray, E; Cohuet, S; Panunzi, I (Elsevier, 2020-03-17)
      BACKGROUND: During a measles epidemic, the Ministry of Public Health (MOH) of the Democratic Republic of the Congo conducted supplementary immunization activities (2016-SIA) from August 28-September 3, 2016 throughout Maniema Province. From October 29-November 4, 2016, Médecins Sans Frontières and the MOH conducted a reactive measles vaccination campaign (2016-RVC) targeting children six months to 14 years old in seven health areas with heavy ongoing transmission despite inclusion in the 2016-SIA, and a post-vaccination survey. We report the measles vaccine coverage (VC) and effectiveness (VE) of the 2016-SIA and VC of the 2016-RVC. METHODS: A cross-sectional VC cluster survey stratified by semi-urban/rural health area and age was conducted. A retrospective cohort analysis of measles reported by the parent/guardian allowed calculation of the cumulative measles incidence according to vaccination status after the 2016-SIA for an estimation of crude and adjusted VE. RESULTS: In November 2016, 1145 children (6-59 months old) in the semi-urban and 1158 in the rural areas were surveyed. Post-2016-SIA VC (documentation/declaration) was 81.6% (95%CI: 76.5-85.7) in the semi-urban and 91.0% (95%CI: 84.9-94.7) in the rural areas. The reported measles incidence in October among children less than 5 years old was 5.0% for 2016-SIA-vaccinated and 11.2% for 2016-SIA-non-vaccinated in the semi-urban area, and 0.7% for 2016-SIA-vaccinated and 4.0% for 2016-SIA-non-vaccinated in the rural area. Post-2016-SIA VE (adjusted for age, sex) was 53.9% (95%CI: 2.9-78.8) in the semi-urban and 78.7% (95%CI: 0-97.1) in the rural areas. Post 2016-RVC VC (documentation/declaration) was 99.1% (95%CI: 98.2-99.6) in the semi-urban and 98.8% (95%CI: 96.5-99.6) in the rural areas. CONCLUSIONS: Although our VE estimates could be underestimated due to misclassification of measles status, the VC and VE point estimates of the 2016-SIA in the semi-urban area appear suboptimal, and in combination, could not limit the epidemic. Further research is needed on vaccination strategies adapted to urban contexts.
    • High cholera vaccination coverage following emergency campaign in Haiti: Results from a cluster survey in three rural Communes in the South Department, 2017

      Sharp, A; Blake, A; Backx, J; Panunzi, I; Barrais, R; Nackers, F; Luquero, F; Deslouches, YG; Cohuet, S (Public Library of Science, 2020-01-31)
      Oral cholera vaccine (OCV) has increasingly been used as an outbreak control measure, but vaccine shortages limit its application. A two-dose OCV campaign targeting residents aged over 1 year was launched in three rural Communes of Southern Haiti during an outbreak following Hurricane Matthew in October 2016. Door-to-door and fixed-site strategies were employed and mobile teams delivered vaccines to hard-to-reach communities. This was the first campaign to use the recently pre-qualified OCV, Euvichol. The study objective was to estimate post-campaign vaccination coverage in order to evaluate the campaign and guide future outbreak control strategies. We conducted a cluster survey with sampling based on random GPS points. We identified clusters of five households and included all members eligible for vaccination. Local residents collected data through face-to-face interviews. Coverage was estimated, accounting for the clustered sampling, and 95% confidence intervals calculated. 435 clusters, 2,100 households and 9,086 people were included (99% response rate). Across the three communes respectively, coverage by recall was: 80.7% (95% CI:76.8-84.1), 82.6% (78.1-86.4), and 82.3% (79.0-85.2) for two doses and 94.2% (90.8-96.4), 91.8% (87-94.9), and 93.8% (90.8-95.9) for at least one dose. Coverage varied by less than 9% across age groups and was similar among males and females. Participants obtained vaccines from door-to-door vaccinators (53%) and fixed sites (47%). Most participants heard about the campaign through community 'criers' (58%). Despite hard-to-reach communities, high coverage was achieved in all areas through combining different vaccine delivery strategies and extensive community mobilisation. Emergency OCV campaigns are a viable option for outbreak control and where possible multiple strategies should be used in combination. Euvichol will help alleviate the OCV shortage but effectiveness studies in outbreaks should be done.
    • High cholera vaccination coverage following emergency campaign in Haiti: Results from a cluster survey in three rural Communes in the South Department, 2017

      Sharp, A; Blake, A; Backx, J; Panunzi, I; Barrais, R; Nackers, F; Luquero, F; Gaston Deslouches, Y; Cohuet, S (Public Library of Sciences, 2020-01-31)
      Oral cholera vaccine (OCV) has increasingly been used as an outbreak control measure, but vaccine shortages limit its application. A two-dose OCV campaign targeting residents aged over 1 year was launched in three rural Communes of Southern Haiti during an outbreak following Hurricane Matthew in October 2016. Door-to-door and fixed-site strategies were employed and mobile teams delivered vaccines to hard-to-reach communities. This was the first campaign to use the recently pre-qualified OCV, Euvichol. The study objective was to estimate post-campaign vaccination coverage in order to evaluate the campaign and guide future outbreak control strategies. We conducted a cluster survey with sampling based on random GPS points. We identified clusters of five households and included all members eligible for vaccination. Local residents collected data through face-to-face interviews. Coverage was estimated, accounting for the clustered sampling, and 95% confidence intervals calculated. 435 clusters, 2,100 households and 9,086 people were included (99% response rate). Across the three communes respectively, coverage by recall was: 80.7% (95% CI:76.8–84.1), 82.6% (78.1–86.4), and 82.3% (79.0–85.2) for two doses and 94.2% (90.8–96.4), 91.8% (87–94.9), and 93.8% (90.8–95.9) for at least one dose. Coverage varied by less than 9% across age groups and was similar among males and females. Participants obtained vaccines from door-to-door vaccinators (53%) and fixed sites (47%). Most participants heard about the campaign through community ‘criers’ (58%). Despite hard-to-reach communities, high coverage was achieved in all areas through combining different vaccine delivery strategies and extensive community mobilisation. Emergency OCV campaigns are a viable option for outbreak control and where possible multiple strategies should be used in combination. Euvichol will help alleviate the OCV shortage but effectiveness studies in outbreaks should be done.
    • 'When you welcome well, you vaccinate well': a qualitative study on improving vaccination coverage in urban settings in Conakry, Republic of Guinea.

      Gil Cuesta, J; Whitehouse, K; Kaba, S; Nanan-N'Zeth, K; Haba, B; Bachy, C; Panunzi, I; Venables, E (Oxford University Press, 2020-01-13)
      BACKGROUND: Recurrent measles outbreaks followed by mass vaccination campaigns (MVCs) occur in urban settings in sub-Saharan countries. An understanding of the reasons for this is needed to improve future vaccination strategies. The 2017 measles outbreak in Guinea provided an opportunity to qualitatively explore suboptimal vaccination coverage within an MVC among participants through their perceptions, experiences and challenges. METHODS: We conducted focus group discussions with caregivers (n=68) and key informant interviews (n=13) with health professionals and religious and community leaders in Conakry. Data were audio-recorded, transcribed verbatim from Susu and French, coded and thematically analysed. RESULTS: Vaccinations were widely regarded positively and their preventive benefits noted. Vaccine side effects and the subsequent cost of treatment were commonly reported concerns, with further knowledge requested. Community health workers (CHWs) play a pivotal role in MVCs. Caregivers suggested recruiting CHWs from local neighbourhoods and improving their attitude, knowledge and skills to provide information about vaccinations. Lack of trust in vaccines, CHWs and the healthcare system, particularly after the 2014-2016 Ebola epidemic, were also reported. CONCLUSIONS: Improving caregivers' knowledge of vaccines, potential side effects and their management are essential to increase MVC coverage in urban settings. Strengthening CHWs' capacities and appropriate recruitment are key to improving trust through a community involvement approach.