An outbreak of measles has been reported at a refugee camp in Calais, northern France, in a setting that public health experts consider especially vulnerable to the rapid spread of the highly contagious virus.
An outbreak of measles has been identified at a refugee camp in Calais, the northern French port city that has hosted large numbers of migrants and refugees for years, many of them living in temporary camps or informal settlements while attempting to reach the United Kingdom. Health experts have long warned that settings of this kind are particularly susceptible to outbreaks of measles and other vaccine-preventable diseases, given the combination of overcrowding, limited sanitation, frequent population movement and uneven vaccination coverage typically found in such camps.
Why measles spreads so easily in camp settings
Measles is one of the most contagious viral diseases known, with a single infected person capable of transmitting the virus to as many as 18 susceptible people in close-contact environments. The virus spreads through airborne respiratory droplets and can remain infectious in the air, or on surfaces, for up to two hours after an infected person has left the area. Making outbreaks harder to contain, those infected are contagious from around four days before their characteristic rash appears until four days afterwards, meaning the virus can spread well before many people realise they are unwell. Symptoms typically begin with a high fever, cough, runny nose and red, watery eyes, followed several days later by a red rash that spreads across the body. In more serious cases, measles can lead to complications including pneumonia, encephalitis, blindness and death, with young children, pregnant women and people with weakened immune systems at greatest risk.
How outbreaks are typically contained
The World Health Organization recommends rapid vaccination campaigns whenever measles outbreaks are identified in displaced populations or refugee settlements, given how quickly the virus can spread in such conditions. Public health responses generally combine vaccination with isolation of suspected cases, contact tracing and health education, in an effort to contain outbreaks as early as possible. The standard MMR vaccine, which protects against measles, mumps and rubella, is highly effective, with two doses providing around 97 per cent protection against measles infection.
Médecins Sans Frontières (MSF) has extensive experience responding to measles outbreaks in refugee camps, conflict zones and other humanitarian emergencies around the world, and organisations of this kind are often central to outbreak response efforts in settings where local healthcare infrastructure is limited or overstretched.
A longstanding concern in Calais
Calais has hosted significant migrant and refugee populations for years, with many people living in temporary camps while attempting onward journeys to the UK. Humanitarian organisations have repeatedly warned that limited access to healthcare and immunisation among displaced populations in such settings increases the risk of outbreaks of vaccine-preventable diseases, including measles, underscoring longstanding calls for improved access to healthcare and vaccination services for people living in informal camps of this kind.
