Nine kilograms. That was the daily difference in tea leaves picked by a Kenyan tea plucker with AIDS in the last three months of his or her life and a healthy worker.

In a painstaking study, presented at a recent conference organised by the Health Economics and HIV/AIDS Research division (Heard) of the University of Natal, researchers from Boston University’€™s Centre for International Health tracked the daily outputs of 54 tea pluckers who had died of AIDS-related illnesses in the last three years of their lives. They compared these with the outputs of 216 healthy workers.

The study not only managed to quantify what AIDS is costing the Rift Valley tea estates in lost productivity but also gives employers involved in similar labour intensive agricultural ventures an idea of how the epidemic could affect them economically.

Two years before their death, workers were already picking 3.3kg less tea a day. One year before death, the gap widened to 5.1kg. In the last three months, the baskets of the pluckers with AIDS were 9.3kg lighter than their healthy co-workers, who usually plucked 41.8kg each day.

“This is possibly an underestimate as workers are allowed to bring informal ‘€˜helpers’€™ with them,” Professor Jon Simon told delegates at the conference.

There are approximately 18 000 workers on the tea estates in the Rift Valley. Last year, 164 workers died, triple the deaths in 1997. Workers with AIDS were also absent for 31 more days than healthy co-workers and had 22 more days on light duty in the last year of their lives.

Simon said the challenge now was to “measure the impact of prevention, treatment and care” on the workforce.

Simon’€™s colleague, Prof Sydney Rosen, told the Heard conference that there was a “systematic under-investment by employers in HIV/AIDS prevention and treatment”.

In a study of the impact of HIV/AIDS on six large enterprises in the retail, agricultural, media, mining and heavy industry sectors in South Africa and Botswana, Rosen found costs varied considerably. The cost per HIV infection of an unskilled worker ranged from $2094 to $15 000 (2001 prices), while the cost of a manager ranged from $8 736 to $65 000.

Costs measured were both direct, such as benefit payments, medical treatment and recruitment, and indirect, such as reduced productivity and increased absenteeism.

In the last year of service, workers with HIV/AIDS took 35 days’€™ more leave than healthy colleagues. When at work, they were 38% less productive and each took about 14 days of their supervisors’€™ time.

“The biggest variables in cost were the death and disability benefits,” said Rosen. “Low risk firms had capped premiums and their employees were treated in public hospitals or company clinics.”

She urged companies to “do their maths” before assuming that prevention and treatment campaigns were bad investments.

If an effective prevention campaign could be run for around $5 to $10 (between R80 and R100 a month) per employee, a financial case could be made for investing in prevention, she said.

If anti-retroviral drugs could prolong an employee’€™s working life by five years and allow full production, companies may also find that they were a profitable investment ‘€“ depending on drug costs and company profits, said Rosen.

While it is too early for Anglo American to quantify the impact of its anti-retroviral programme, which only started five months ago, the corporation’€™s senior vice-president, Dr Brian Brink, said that “there is no doubt the impact of the treatment is profound”.

“You just need to look at the difference in the faces of the people getting it. We have taken away the message of death,” said Brink. Some 160 employees are getting the drugs at present, and this number is expected to rise to 3 000 by the end of the year.

Over the next five years, Aurum Health Research and the London School of Hygiene and Tropical Medicine will assist Anglo to measure the impact of HIV/AIDS on its companies and evaluate the provision of anti-retroviral drugs.

However, it is already clear that HIV/AIDS is having a serious and debilitating effect, with AIDS-related costs were as high as 9% of some firm’€™s profits. About 12 600 gold workers (28% of the workforce) and 11 200 platinum workers (25%) are estimated to be HIV positive.

Aurum’€™s Gavin Churchyard told the conference that in the corporation, deaths from tuberculosis were now double those of mine accidents.

“HIV positive workers are three times more likely than HIV negative workers to be hospitalised, more than twice as likely to be readmitted, and their mortality rate is almost 10 times higher,” said Churchyard.

TB and pneumonia were the leading causes of hospitalisation, while crytococcocal disease was the leading cause of death.

Anglo has been criticised for not extending anti-retroviral treatment to the partners of their workers. However, Brink stressed that Anglo intended to take treatment to communities as it “does not want to create little islands of privilege”. However, for this to happen there needs to be a partnership with international donors and government, he said.