'The security of our staff, who are being intimidated by parties to the conflict, is a non-negotiable prerequisite for our presence' the ICRC said.
In the first three months of 2018, hospitals and clinics recorded 184 cases, with the actual number of measles infections thought to be higher.
A low-cost prosthetics production centre in Irbid has been helping those who lost limbs in the region's wars regain mobility.
Yemen's Ministry of Public Health has been working with international organisations to provide vaccinations and treatment in Ibb province.
The planned opening of a wastewater treatment plant in Zahle is a positive step, but much more must be done to clean up the river.
Preventive measures that include mosquito fumigation, education and monitoring are being conducted in the six most-affected provinces.
The number of cholera cases continues to rise, with the UN now warning that by the end of August, 300,000 people could become infected.
With the disease killing nearly one person every hour, Yemeni and international officials warn that not enough is being done to curb its spread.
The massive influx of Syrian refugees has strained the water infrastructure and created unsanitary conditions that must be addressed, officials say.
Medical teams in Lebanon and Jordan are stationed near the border with Syria to treat people with injuries caused by the armed conflict.