Facility capacity and provider knowledge for cholera surveillance and diarrhoea case management in cholera hotspots in the Democratic Republic of Congo - a mixed-methods study

BACKGROUND

Wider healthcare-strengthening interventions are recommended in cholera hotspots and could benefit other types of diarrhoeal diseases which contribute to greater mortality than cholera.

OBJECTIVE

Describe facility capacity and provider knowledge for case management of diarrhoea and cholera surveillance in cholera hotspots in the Democratic Republic of Congo (DRC) among health facilities, drug shops, and traditional health practitioners.

METHODS

We conducted a sequential exploratory mixed-method study, using focus group discussions, facility audits, and provider knowledge questionnaires during September and October 2022 in North Kivu and Tanganyika provinces, Eastern DRC. Content analysis was used for qualitative data. Quantitative data were summarised by facility level and healthcare provider type. Audit and knowledge scores (range 0-100) were generated. Multivariable linear regression estimated association between scores and explanatory factors. Qualitative and quantitative data were triangulated during interpretation.

RESULTS

Overall, 244 facilities and 308 providers were included. The mean audit score for health facilities was 51/100 (SD: 17). Private facilities had an -11.6 (95% CI, -16.7 to -6.6) lower adjusted mean score compared to public. Mean knowledge score was 59/100 (95% CI, 57 to 60) for health facility personnel, 46/100 (95% CI, 43 to 48) for drug shop vendors and 37/100 (95% CI, 34 to 39) for traditional health practitioners. Providers had particularly low knowledge concerning when to check for low blood sugar, use of nasogastric tubes, and dosing schedules. Knowledge about case definitions for cholera was similar between groups (range 41-58%) except for traditional health practitioners for the definition during an outbreak 15/73 (21%).

CONCLUSIONS

Increasing awareness of cholera case definitions in this context could help improve cholera surveillance and control. Increased support and supervision, especially for private providers, could help ensure facilities are equipped to provide safe care. More nuanced aspects of case management should be emphasised in provider training.

Effectiveness of one dose of killed oral cholera vaccine in an endemic community in the Democratic Republic of the Congo: a matched case-control study

BACKGROUND

A global shortage of cholera vaccines has increased the use of single-dose regimens, rather than the standard two-dose regimen. There is sparse evidence on single-dose protection, particularly in children. In 2020, a mass vaccination campaign was conducted in Uvira, an endemic urban setting in eastern Democratic Republic of the Congo, resulting in largely single-dose coverage. We examined the effectiveness of a single-dose of the oral cholera vaccine Euvichol-Plus in this high-burden setting.

METHODS

In this matched case-control study, we recruited individuals with medically attended confirmed cholera in the two cholera treatment facilities in the city of Uvira. The control group consisted of age-matched, sex-matched, and neighbourhood-matched community individuals. We recruited across two distinct periods: Oct 14, 2021, to March 10, 2022 (12-17 months after vaccination), and Nov 21, 2022, to Oct 18, 2023 (24-36 months after vaccination). Study staff administered structured questionnaires to all participants to capture demographics, household conditions, potential confounding variables, and vaccination status. The odds of vaccination for the case and control groups were contrasted in conditional logistic regression models to estimate unadjusted and adjusted vaccine effectiveness.

FINDINGS

We enrolled 658 individuals with confirmed cholera and 2274 matched individuals for the control group. 99 (15·1%) individuals in the case group were younger than 5 years at the time of vaccination. The adjusted single-dose vaccine effectiveness was 52·7% (95% CI 31·4 to 67·4) 12-17 months after vaccination and 44·7% (24·8 to 59·4) 24-36 months after vaccination. Although protection in the first 12-17 months after vaccination was similar for children aged 1-4 years and older individuals, the estimate of protection in children aged 1-4 years appeared to wane during the third year after vaccination (adjusted vaccine effectiveness 32·9%, 95% CI -30·7 to 65·5), with CIs spanning the null.

INTERPRETATION

A single dose of Euvichol-Plus provided substantial protection against medically attended cholera for at least 36 months after vaccination in this cholera-endemic setting. Although the evidence provides support for similar levels of protection in young children and others in the short term, protection among children younger than 5 years might wane significantly during the third year after vaccination.

FUNDING

Wellcome Trust and Gavi, the Vaccine Alliance.

Enhanced cholera surveillance to improve vaccination campaign efficiency

Systematic testing for Vibrio cholerae O1 is rare, which means that the world's limited supply of oral cholera vaccines (OCVs) may not be delivered to areas with the highest true cholera burden. Here we used a phenomenological model with subnational geographic targeting and fine-scale vaccine effects to model how expanding V. cholerae testing affected impact and cost-effectiveness for preventive vaccination campaigns across different bacteriological confirmation and vaccine targeting assumptions in 35 African countries. Systematic testing followed by OCV targeting based on confirmed cholera yielded higher efficiency and cost-effectiveness and slightly fewer averted cases than status quo scenarios targeting suspected cholera. Targeting vaccine to populations with an annual incidence rate greater than 10 per 10,000, the testing scenario averted 10.8 (95% prediction interval (PI) 9.4-12.6) cases per 1,000 fully vaccinated persons while the status quo scenario averted 6.9 (95% PI 6.0-7.8) cases per 1,000 fully vaccinated persons. In the testing scenario, testing costs increased by US$31 (95% PI 25-39) while vaccination costs reduced by US$248 (95% PI 176-326) per averted case compared to the status quo. Introduction of systematic testing into cholera surveillance could improve efficiency and reach of global OCV supply for preventive vaccination.

Exploring different health care providers´ perceptions on the management of diarrhoea in cholera hotspots in the Democratic Republic of Congo: A qualitative content analysis

Global cholera guidelines support wider healthcare system strengthening interventions, alongside vertical outbreak responses, to end cholera. Well-trained healthcare providers are essential for a resilient health system and can create synergies with childhood diarrhoea, which has higher mortality. We explored how the main provider groups for diarrhoea in cholera hotspots interact, decide on treatment, and reflect on possible limiting factors and opportunities to improve prevention and treatment. We conducted focus group discussions in September 2022 with different healthcare provider types in two urban and two rural cholera hotspots in the North Kivu and Tanganyika provinces in the Eastern Democratic Republic of Congo. Content analysis was used with the same coding applied to all providers. In total 15 focus group discussions with medical doctors (n = 3), nurses (n = 4), drug shop vendors (n = 4), and traditional health practitioners (n = 4) were performed. Four categories were derived from the analysis. (i) Provider dynamics: scepticism between all cadres was prominent, whilst also acknowledging the important role all provider groups have in current case management. (ii) Choice of treatment: affordability and strong caregiver demands shaped by cultural beliefs strongly affected choice. (iii) Financial consideration on access: empathy was strong, with providers finding innovative ways to create access to treatment. Concurrently, financial incentives were important, and providers asked for this to be considered when subsiding treatment. (iv) How to improve: the current cholera outbreak response approach was appreciated however there was a strong wish for broader long-term interventions targeting root causes, particularly community access to potable water. Drug shops and traditional health practitioners should be considered for inclusion in health policies for cholera and other diarrhoeal diseases. Financial incentives for the provider to improve access to low-cost treatment and investment in access to potable water should furthermore be considered.

Genomic Microevolution of Vibrio cholerae O1, Lake Tanganyika Basin, Africa

Africa's Lake Tanganyika basin is a cholera hotspot. During 2001-2020, Vibrio cholerae O1 isolates obtained from the Democratic Republic of the Congo side of the lake belonged to 2 of the 5 clades of the AFR10 sublineage. One clade became predominant after acquiring a parC mutation that decreased susceptibility to ciprofloxacin.