The number of cases of diphtheria among asylum seekers who have recently arrived in the UK has risen to more than 50, the BBC understands.
It comes after it was confirmed that one migrant who died after being held at Manston processing centre in Kent had contracted the disease.
The Home Office said it takes the welfare of those in its care seriously.
This week, health officials are set to confirm there have been more than 50 diphtheria cases among asylum seekers this year, the BBC understands.
In 2021, there were three of the same strain, according to government data.
Diphtheria is a highly contagious infection that affects the nose, throat and sometimes cause ulcers on the skin.
According to the NHS website, it's spread by coughs and sneezes or through close contact with someone who is infected, and in serious cases can be fatal.
Babies and children in the UK are vaccinated against diphtheria, meaning cases are rare. However, the infection is potentially dangerous to migrants who come from countries where this is not the case.