Cholera outbreak: epidemiological indicators, projection and needs of a treatment centre

Facility case fatality rate: 4 / 183 = 2.19% (an approximation, since the exact denominator would be the number of patients treated in facilities).

Interpretation: the overall CFR of 6.01% is far above the usual target of less than 1% with adequate case management. It mainly reflects an access problem: 7 of the 11 deaths occur at home, and the CFR is highest in the posts far from the CTC (Itoculo and Netia), where there is no ORP. The facility CFR (2.19%) also exceeds 1%, which raises the question of the quality of case management (triage, rehydration, overcrowding). The small numbers in Netia (16 cases, 2 deaths) make its rate very unstable. The highest attack rate is in Monapo-Sede, but Itoculo is growing faster.

Weekly totals: W36 0; W37 4; W38 14; W39 29; W40 53; W41 83. Ratios: W39/W38 = 2.07; W40/W39 = 1.83; W41/W40 = 1.57. The epidemic is growing rapidly; growth is slowing slightly but remains above + 50% per week. Spread: started in Monapo-Sede (W37), then Itoculo (W38) and Netia (W39); Itoculo went from 15 to 28 cases (x 1.87) in one week.

Projection: W42 = 83 × 1.3 = 107.9, i.e. 108 cases; W43 = 108 × 1.3 = 140.4, i.e. 140 cases; total 248 cases over two weeks.

Prudence: the + 30% assumption is lower than the observed growth (+ 57% last week): it risks underestimating needs. I would also present a high scenario (for example + 50%: 125 then 188 cases) and revise orders every week. Conversely, under-reporting is likely in the posts without an ORP.

Cases (248): plan C 25% = 62; plan B 45% = 111.6, i.e. 112; plan A 30% = 74.4, i.e. 74 (total 248).

Ringer's lactate: 62 × 8 = 496 bags; × 1.2 = 595.2, i.e. 596 bags of 1 L.

ORS: 62 × 6 + 112 × 8 + 74 × 4 = 372 + 896 + 296 = 1,564; × 1.2 = 1,876.8, i.e. 1,877 sachets.

Doxycycline: 62 × 3 = 186; × 1.2 = 223.2, i.e. 224 tablets.

Beds: 70% of cases are admitted (plans B and C). W42: 108 × 0.7 = 75.6 admissions, i.e. 10.8 per day × 2 days = 22 beds; W43 (peak): 140 × 0.7 = 98, i.e. 14 per day × 2 days = 28 beds. The CTC has only 20 beds and is already almost full (18 patients and 3 on mats): at least 8 additional beds are needed from W42, and preferably 35 beds to allow for the high scenario, with the corresponding staff, chlorinated water and space. Cholera beds (cots with a hole and bucket) are needed to monitor losses.

1. Bring treatment closer to patients: open at least one ORP in Itoculo and one in Netia, and a cholera treatment unit (CTU) in Itoculo; indicator: time between onset of symptoms and rehydration, community CFR.
2. Quality of case management at the CTC: triage at entry, rehydration according to WHO plans, expansion to 35 beds, staffing ratios; indicator: facility CFR below 1%.
3. Surveillance and community alert: case definition disseminated, community volunteers trained in referral and home use of ORS, line list kept up to date, mapping of cases by village; indicator: completeness and timeliness of notification.
4. Case-area targeted water and hygiene interventions (with the WASH team): chlorination of water points, distribution of water treatment products and soap to case households and their neighbours, measurement of free residual chlorine; indicator: % of case households reached within 48 hours.
5. Risk communication, prevention and safe and dignified burials, and preparation, with the Ministry of Health, of a request for oral cholera vaccine to the International Coordinating Group (ICG); indicators: number of sessions and people reached, request submitted.

I understand the administrator's concern, but I cannot keep the name of the disease quiet: cholera is a notifiable disease, reported by the Ministry of Health under the International Health Regulations (2005); vague communication delays care-seeking and prevents people from adopting the right practices (ORS, treated water, hygiene, safe burials). Hiding the epidemic would cost the population's trust when the truth comes out. Public communication on confirmation is the responsibility of the Ministry of Health: I do not bypass it, but I do not spread false information. I propose calm, practical communication, prepared with the health authorities and community leaders: what the disease is, that it can be treated, where to get treatment. For the market, I propose measures (handwashing points, checks on water and food sold) rather than closure. I inform my manager of the request.