Public health priorities in emergencies

1Why people die in emergencies

In the first weeks of a crisis, excess deaths are rarely due to injuries themselves. They come mainly from preventable and treatable diseases: diarrhoea (including cholera), acute respiratory infections, measles and malaria, made worse by acute malnutrition. Added to these are complications of pregnancy and childbirth, neonatal deaths and the interruption of treatment for chronic diseases (diabetes, hypertension, HIV, tuberculosis).

Risk factors combine: overcrowding, lack of water and sanitation, inadequate shelter, low vaccination coverage, collapse of health services, insecurity. As a result, the health response is not limited to health facilities. It also relies on water, sanitation, nutrition and shelter.

2Measuring mortality: CMR and U5MR

The crude mortality rate (CMR) is the most important indicator of a crisis. It is expressed as deaths per 10,000 people per day:

• CMR = number of deaths ÷ (population × number of days) × 10,000.
• The under-5 mortality rate (U5MR) is calculated in the same way, for children under 5 only.

Example: 30 deaths in 15 days in a camp of 20,000 people give 30 ÷ (20,000 × 15) × 10,000 = 1 death per 10,000 per day. Sources include home death surveillance by community workers, health facility registers, gravediggers and religious leaders, and retrospective mortality surveys (SMART method).

3Sphere emergency thresholds

Sphere compares observed mortality with the region's baseline mortality before the crisis:

• An emergency is declared when the CMR reaches or exceeds double the baseline mortality.
• If the baseline mortality is not known, the threshold of 1 death per 10,000 per day is used for the CMR and 2 deaths per 10,000 per day for the U5MR.
• The aim of the response is to bring the CMR below 1/10,000/day and, ideally, below double the baseline mortality.

Above 2/10,000/day, the situation is out of control; above 5/10,000/day, it is catastrophic. A U5MR rising faster than the CMR often signals a measles or diarrhoea outbreak, or a worsening of malnutrition.

4Initial assessment and priorities

The rapid assessment (often in the form of a multi-cluster initial rapid assessment, MIRA, or a cluster health assessment) answers simple questions within a few days: how many people, what mortality, which diseases, what nutritional status, which services are still functional (HeRAMS), which shortages, which epidemic risks.

The classic priorities of the first weeks: measles vaccination with vitamin A, water and sanitation (at least 15 litres per person per day), screening and treatment of malnutrition, access to primary health care with essential medicines, management of diarrhoea, pneumonia and malaria, the Minimum Initial Service Package for reproductive health, an early warning system. These priorities are decided with the Ministry of Health and the Health Cluster, based on data.