A child, not yet four years of age, scratches listlessly at the lesions on his legs and arms. His father, eyes sunken in their sockets, sinks back in his crib. The boy's mother is dead, taken by the virus, and her son will follow shortly.
Tinashe is an AIDS "orphan", one of more than 500,000 children in Zimbabwe who have lost their mothers to the deadly disease. Worse, the virus was passed on in her blood and Tinashe too is infected.
Children are the saddest victims of this African holocaust, which is ripping the heart out of families throughout the continent. Shunned by their own society, which is so fearful of the new plague in its midst, their plight is also ignored by the West, which seems to have lost interest in AIDS.
On her regular visit to his oneroom home in Mbare, a slum district of Harare, Sister Eileen Clear blesses Tinashe with aroma therapy oil and prays with his father for his wellbeing. With her colleagues in the Mashambanzou Care Trust, she fights the disease with nothing stronger than a bottle of oil and a message of hope.
"In our view, the power of love and the power of affirmation can be stronger than AZT [the drug used in the West to treat HIV patients]," she says. "If people know they're loved, they respond and their immune system responds."
Nearby, the nuns run a creche for AIDS orphans. Smiling faces and full bellies cannot hide a mountain of tragedies. Twins Collettea and Colliwe are only three years of age, but have lost both their parents and live with their grandfather.
Tafadzwa still has her father, but he is deaf and dumb. "Her uncles were making a woman out of her - and they gave her the virus," explains the co-ordinator, Ms Dorothy Abdul. Tafadzwa is four.
Up to three-quarters of these children will turn out to be HIV positive, but until they reach the age of 18 months, it is not possible to be certain that their mothers have infected them.
The nuns feed them well, and give them the love and attention they never get from their relatives. Those who make it to school go to the top of their classes.
"By taking good care of them, they become normal. But then the virus explodes when they start to get periods or sexual urges," says Abdul. Few of those infected will live to be teenagers.
The spread of the epidemic has foisted parental duties on mere children. At Epworth, Sister Eileen visits Rumbi (16), who looks after four younger children in a single-room mud hut. Rumbi's mother died of AIDS, as did an older, mentally-handicapped sister who was raped. Her father remarried, leaving his first family to tend for itself.
Just being a teenager is a trauma in itself. But Rumbi is missing school because of her duties, and she has to cope with the sneers of neighbours.
"They look down on us because we need welfare," she tells Sister Eileen, tears streaming down her face.
Back at the Mashambanzou care centre, a 24-year-old woman has died during the night. A nine-year-old girl, the victim of a rape, is admitted. The local staff who care for the sufferers are HIV positive themselves.
The centre was founded by two Irish nuns of the Little Company of Mary, who had grown tired of tending to the wealthy in a private hospital in Harare. The nuns have cobbled together financial support from a variety of donors to bring succour to AIDS sufferers. The then president, Mrs Mary Robinson, visited them in 1994, and Princess Diana also came on a private visit.
Sister Noreen Nolan acknowledges their work is "only a drop in the ocean". The death toll from AIDS in Zimbabwe is the equivalent of four large plane crashes every week.
The disease has cut a swathe through all areas of life. Coffinmakers are short of wood; employers are losing workers. Many of those affected are young and highly qualified, and their deaths are an incalculable loss to the economy.
An Irish civil engineer tells me four of his colleagues have died of AIDS in the past year: "They're at their desks one day, and gone the next. No-one speaks about what happened to them."
Official figures show that life expectancy in Zimbabwe has dropped from 61 years in 1990 to only 49 years today. A further drop, to 30 years, is predicted.
Decades of investment and development have been wiped out as AIDS patients overburden the health system. Eighty per cent of hospital beds are occupied by sufferers, and 20 per cent of health spending goes on terminal care for their last year of life.
Zimbabwe's tragedy is being repeated in most states in sub-Saharan Africa. As the incidence of HIV and AIDS drops in western countries, Africa accounts for 20 million out of a total of 30 million cases worldwide.
AIDS is now mainly a poor person's disease, like malaria. And as in the case of malaria, the poor in Africa will have to wait a long time for the West to find a cheap cure. New drug cocktails have been developed to extend the life of wealthy HIV sufferers in the West, but these cost £10,000 per patient per year. Many developing countries spend less than £5 per patient per year.
Everywhere, prevention is better than cure. In Africa, prevention is the only solution. Zimbabwe has managed to cut by half the level of sexually-transmitted diseases among miners and in the army by distributing free condoms. In stores, "Protector", the most common brand of condom, is sold openly alongside school jotters and pencils.
But educating for change in a culture of male permissiveness and female acceptance will not be easy. Sister Noreen believes that AIDS is a social problem, not a health one. Tackling the disease means tackling the social circumstances, such as poverty and overcrowding, in which the disease thrives.
Lifeskills programmes for schools which were developed by Unicef and funded by Irish Aid are explicit about the dangers of unprotected sex.
But cultural habits die hard. Men are unwilling to use condoms. As one worker reports: "They say it's like eating a sweet with the paper on."