Surveillance, epidemics and coordination

1The early warning system (EWARN)

EWARN (Early Warning, Alert and Response Network) is a simplified surveillance system, set up when the national system is no longer functioning. It is based on:

• a short list of priority diseases (acute watery diarrhoea, bloody diarrhoea, measles, malaria, meningitis, acute flaccid paralysis, haemorrhagic fever, acute jaundice);
• standard case definitions, simple and known to all health workers;
• a weekly report from all facilities, including a "zero report" when no cases are seen;
• alert thresholds: a single suspected case of cholera, measles, flaccid paralysis or haemorrhagic fever triggers an immediate alert;
• verification of each alert within 24 hours and a rapid investigation.

Two quality indicators: the completeness and timeliness of reports, ideally at least 80%. A system that receives only one report in two does not see epidemics.

2Responding to cholera

Cholera can kill within hours through dehydration, but the case fatality rate must remain below 1% with good case management. The response combines:

• case management: oral rehydration points (ORS) in the community, cholera treatment units and centres (CTUs, CTCs) for intravenous rehydration with Ringer's lactate for severe cases, antibiotics according to recommendations;
• confirmation by rapid diagnostic tests followed by laboratory culture;
• WASH: water chlorination, disinfection of case households, targeting of the "rings" around cases (CATI), hygiene, safe burials;
• oral cholera vaccine (OCV), requested from the International Coordinating Group (ICG);
• risk communication and community engagement to counter rumours.

A case fatality rate above 1% signals delayed treatment, insufficient access or quality of care that needs to be corrected, often by more ORS points as close as possible to households.

3Responding to measles and other epidemics

In a camp, a single confirmed case of measles justifies a response. Cases are isolated and treated (vitamin A, treatment of complications, nutritional monitoring), the vaccination campaign is launched or completed and active case finding is carried out. For any epidemic, the approach is the same: confirm the outbreak, define cases, describe by time, place and person (epidemic curve, map, age), formulate hypotheses, put control measures in place and monitor the evolution every day.

The International Health Regulations (2005) require States to notify WHO of certain events. NGOs send their alerts to the Ministry of Health and the cluster, never to the media first. Preparedness stocks (cholera kits, rapid tests, vaccines via the ICG) are prepositioned before the high-risk season.

4Health Cluster, HeRAMS and protection of health care

The Health Cluster, led by WHO at global level, coordinates with the Ministry of Health: joint risk analysis, 4W mapping, harmonisation of protocols and medicine lists, response plan, monitoring of gaps and advocacy. The HeRAMS system (Health Resources and Services Availability Monitoring System) records, facility by facility, what is really working: building, staff, equipment, services available, reasons for unavailability. It prevents opening a health post next to a centre that is already working.

Attacks on health care (strikes on hospitals, violence against health workers, obstruction of ambulances, looting) are prohibited by international humanitarian law, as recalled by Security Council resolution 2286 (2016). WHO documents them in its Surveillance System for Attacks on Health Care (SSA). For an NGO: report every incident, protect staff and patients, respect neutrality (no weapons in facilities) and do not suspend care without a continuity plan.