In all, 318 cases were identified of which 280 died.
Three new cases a day are still being identified, on average.
In the same period last year, the department identified 416 new cases.
Less than 100 cases have been identified since its discovery.
In 1981, one case was identified; by 1986 this had grown to 60 a month.
The first cases were identified in 1997 and its cause is not fully understood.
A third brother did not develop symptoms, and no other cases have been identified among others in the community.
Since the first case was identified in 1990, the number of infections has continued to grow.
It appears that for these types of conditions few new cases are identified in later life.
As of June 8, 195 cases caused by the other two had been identified worldwide.
