Table 2.

Estimated costs and benefits after the first year of three models of screening blood donors for human T cell leukaemia/lymphoma virus in Sweden. In the first model all donations were tested; in the second model only new donors were tested and then retested after 5 years; in the third model donors were only tested at the time of their first donation

	Model
	Every donation tested	New donors tested and then retested after 5 years	Only new donors tested
Costs each year ($ million)	3.02	0.32	0.17
Total costs ($ million) for:
Each positive donor identified	1.90	0.22	0.13
Each transmission prevented	5.59	0.70	0.44
Each case of disease prevented	222	25	15
Each death prevented	540	63	36
No of donors identified as positive each year*	0.54	0.46	0.39
No of events prevented each year:
Transmission of the virus†	1.59	1.47	1.35
Cases of disease	0.0136	0.0126	0.0116
Deaths (incidence)	0.0056 (1/180 years)	0.0051 (1/195 years)	0.0047 (1/210 years)

^*Infected new donors (0.39) + newly infected old donors.  

^†No of donations prevented (including future donations) × transfusion/donation ratio × donors identified as positive × transmission risk.