Measles outbreak: surveillance analysis, mortality and vaccination response planning

Yes, confirmed outbreak: 4 out of 5 cases IgM positive, rapid and continuous increase in cases. WHO suspected case definition: fever with maculopapular rash and at least one of the following: cough, runny nose (coryza) or conjunctivitis; once the outbreak is confirmed, new cases may be classified by epidemiological link without systematic sampling.

Figures: cumulative cases 3 + 2 + 6 + 14 + 31 + 58 + 96 = 210; deaths 0 + 0 + 0 + 1 + 2 + 4 + 7 = 14. Attack rate: 210 / 180,000 = 116.67 per 100,000. Case fatality rate: 14 / 210 = 6.67%, high, which points to late or inadequate case management, complications (malnutrition, diarrhoea, pneumonia) and probable under-reporting of mild cases. Cases have almost doubled every week since W39 (14, 31, 58, 96).

Line list: 5 of 12 cases under 5 years (41.7%), 6 aged 5 to 14 years (50.0%), 1 adult: 11 of 12 (91.7%) are aged between 6 months and 14 years, which justifies a campaign extended to this group. 9 of 12 (75.0%) have no documented dose (7 unvaccinated and 2 unknown); of the 3 with "1 dose", 2 are only reported. Kalonda accounts for 6 of the 12 cases and both deaths: it is the health area of the displacement site. 68% coverage and no campaign for 4 years: accumulation of susceptible individuals.

Crude mortality rate: 61 / (4,850 × 90) × 10,000 = 61 / 436,500 × 10,000 = 1.40 deaths per 10,000 people per day. Under 5: 33 / (1,020 × 90) × 10,000 = 33 / 91,800 × 10,000 = 3.59 per 10,000 per day.

Interpretation: both rates exceed the commonly used emergency thresholds of 1 per 10,000 per day for crude mortality and 2 per 10,000 per day for under-5s; Sphere also recommends comparing with the regional baseline, a situation being critical when it doubles. The site is in an emergency situation. 14 of the 33 child deaths (42%) are attributed to "fever with rash", consistent with measles; diarrhoea and malaria, often aggravated by measles and malnutrition, explain another share. Limitations: recall bias, causes reported by families, modest sample size (wide confidence interval) and unknown mid-period population.

Target: 180,000 × 43% = 77,400 children. Age range justified by the line list (91.7% of cases between 6 months and 14 years) and the absence of a campaign for 4 years.

Doses: wastage factor = 1 / (1 − 0.15) = 1.176; 77,400 / 0.85 = 91,058.8, i.e. 91,059 doses; vials: 91,059 / 10 = 9,105.9, i.e. 9,106 vials.

Supplies: auto-disable syringes 77,400; reconstitution syringes 9,106; safety boxes: (77,400 + 9,106) / 100 = 865.06, i.e. 866. In practice a reserve is added (often 10%) according to national guidelines.

Teams: 77,400 / (300 × 5) = 51.6, i.e. 52 teams.

Organisation: (1) cold chain: storage capacity, vaccine carriers and ice packs, reconstituted vaccine discarded after 6 hours or at the end of the session; (2) microplanning by health area, starting with Kalonda and the displacement site, with fixed and mobile teams; (3) community mobilisation and coordination with the Expanded Programme on Immunization; (4) surveillance of adverse events following immunization, waste management, and a rapid coverage survey after the campaign, with a target of at least 95%.

1. Free case management: vitamin A for all cases (two doses 24 hours apart, age-based dosage: 50,000 IU under 6 months, 100,000 IU from 6 to 11 months, 200,000 IU from 12 months); treatment of complications (pneumonia, diarrhoea, otitis, eye lesions); isolation of hospitalised cases.
2. Reducing case fatality: rapid training of health workers on protocols, supply of medicines, referral of complicated cases, free care to remove the financial barrier.
3. Malnutrition screening (mid-upper arm circumference) of all cases and of the children in the site, with referral to nutritional treatment.
4. Enhanced surveillance: daily line list, active case finding in the community and at the site, monitoring of case fatality by health area.
5. Risk communication: danger signs, early consultation, importance of vaccination, in liaison with community volunteers.
6. Basic care in the Kalonda site: given the mortality, access to primary health care, management of malaria and diarrhoea, and coordination with WASH and nutrition actors.

I do not fund on an inflated basis. 95,000 instead of 77,400 means 17,600 additional children (23%), i.e. about 20,706 additional doses (17,600 / 0.85) and associated allowances and supplies, without justification. I remain respectful of his authority: the campaign belongs to the ministry, and we are supporting it.

I propose: (1) to review the population data together (census, health worker headcounts, displacement site data); if an underestimate is demonstrated, we adjust with supporting evidence; (2) a transparent reserve, in line with national guidelines, rather than an inflated target; (3) for the supervisors, to fund only positions defined in the microplan, with a role, an area and supervision reports, paid at harmonised rates, with signed lists or mobile payment. I document the discussion and inform the country director. If the pressure continues, I discuss it with the other campaign partners to reach a common position, without public accusation.