A chance conversation over a drink led Anthony Haji to become one of Tanzania's leading mosquito net manufacturers.
For 20 years the family's textile mill in the industrial quarter of Dar es Salaam had been mothballed - put out of business by the second-hand clothing market.
In 1997, learning of the need for bed nets in the fight against malaria, Haji rushed over to the factory to see whether the machines, which used to produce polyester fabrics, were capable of producing nets.
Two weeks later a sample was ready and he took his first order. In 1998, Haji, a Tanzanian national with a Swiss mother, started production with a staff of 16.
Today he employs 180 people and sells 300,000 nets a year and his Textile Manufacturers of Tanzania (TMTL) is the third player in a thriving domestic market.
Inside the factory, sewing machines whizz and whirr as dozens of stitchers put together the blue, green and white netting that has been woven on the factory's 30-year-old German looms.
TMTL's nets are typically conical or rectangular in shape and come in single, mother and baby, and family size.
Conical nets, which are easier to hang and fold up, are handy in small rooms where beds are used as seats or tables during the day. Rectangular nets hang from string or frames and take up more space.
"All the nets have a 20 centimetre rigid border which in our case is the original polyester fabric which the company used to make 20 years ago," said Haji.
"The reason for this is that most Tanzanians sleep on the floor on a mattress and they need the border of the net to tuck under their mattress.
"We also devised a very cheap brand with no border made from cut pieces of net that we would otherwise throw away. It's for the poor man on the street who can really not afford anything else but still needs to be protected from mosquitoes."
Do or dye
When the factory started its operation, it was able to use up the old stocks of polyester that had lain unused since the machines had fallen idle.
Today, the raw material comes from several countries including Thailand and India.
As for the money Haji took from his first order, he ploughed it straight back into the business, buying a dyeing machine from India.
"Blue is a best seller," he explained. "The white nets are the cheapest nets to produce because you don't really need a dye, but, of course, to be able to market a product, there isn't really a lot you can do to a net other than size and colour."
"The other practical reason for having colours is that Tanzanians actually sleep in very difficult conditions. They sleep in muddy areas, dusty areas, wet environments, so white gets dirty very quickly."
TMTL sells most of its nets in and around Dar es Salaam. Over the counter sales play an important role.
About 40 street vendors turn up each week, pay cash for a bundle of 100 nets and disappear. Others share a taxi, which they pile high with nets, before heading off in search of customers.
Tanzania is now by far the largest producer of bed nets in Africa - a far cry from the 1980s when nets were rare in Tanzania and cost between $10 and $15, assuming you could find one.
The boom began in 1994 when one factory in the northern city of Arusha, stimulated partly by a change in the tax structure and partly by changes in other textile markets, began to make ready-made nets at a moderate price for the mass market.
Sunflag's Mmbu net sold for $4.25 wholesale and $7 retail and annual sales were about quarter of a million a year.
In 1998, another Arusha manufacturer, A-Z Textile Mills entered the market and shortly afterwards TMTL joined the fray.
They were both offered a guaranteed market for a certain number of nets by Population Services International (PSI), an American NGO, which uses commercial marketing techniques to meet public health objectives - a technique known as social marketing.
Competition has brought a fall in prices and an increase in quality and diversity.
"The first net I ever provided to PSI, I sold at 5,800 shillings in 1998 and at that time the dollar to the shilling was far more favourable than it is today," recalls Haji.
"Nets today in Tanzania retail at around 3,500 shillings, which is just under $3.50, but wholesale nets are closer to $2.50 so it's a massive dip in prices but there again the volumes have significantly increased."
Although Tanzania was one of the first countries in Africa to waive tariffs on netting material, an oversight in last year's taxation reforms has led to the reintroduction of 20 per cent duty on imported raw materials for net manufacturers.
Haji and his two larger rivals have not yet passed on the extra cost to consumers but the longer they have to wait for reimbursement, the likelier this becomes.
The three factories are capable of producing up to six million nets a year for use at home and in neighbouring countries.
Between them, they sold 1.5 million nets on the domestic market last year and project even better results for 2003.
On average, one net protects two people, which means protection for about three million people a year at current rates of sale.
In an important development last October, the manufacturers agreed to package all their nets for the local market with sachets of insecticide treatment. Since then, they have sold more than half a million of these bundled nets.
"Tanzanians have a net culture but it is still a major spend for your average person," says Haji.
"Three dollars or 3,500 shillings may not sound much but for a Tanzanian it is a gamble between buying food for his family, paying bus fares to get to work or getting this really expensive piece of equipment which it is hard to believe can save lives in the long term."
swissinfo, Vincent Landon in Tanzania
In the 1980s, nets were rare in Tanzania and fetched about $10-15.
In 1994, Sunflag sold 250,000 nets at $7 each.
By 1997 sales had increased to 450,000 annually.
When A-Z and TMTL entered the market in 1998, net prices fell and quality improved.
Last year, 1.5 million nets were sold in Tanzania at about $3 each.
In October, manufacturers agreed to bundle nets with doses of insecticide.