In Dzumeri in Limpopo in Northern province, men in blue overalls are readying themselves for the malaria season.

Armed for battle against one of Africa's deadly diseases, they brandish canisters filled with the deadly insecticide DDT.

Despite the chemical's being banned in many countries over the damage it can cause to the environment, South Africa says it has enabled the country to drastically reduce malaria incidents in the past four years.

When sprayed properly it can keep mosquitoes carrying malaria at bay for more than eight months.

In this province alone, more than a million structures, mostly homes, are sprayed every year.

At first, the people were apprehensive about having their walls sprayed and locked their doors every time the men in blue appeared

But nowadays they get a 90% coverage rate.

Their success is pinned on educational drives that include radio talk shows, posters and brochures in local languages and door-to-door campaigning.

Zatley Sekgobela, the man in charge, says they have an intensive three-week training programme to ensure they do not get the spraying wrong.

"We want them to deposit three grams per square km of insecticide. Not more or less... When they spray it must be 45 cm from the wall. We don't want to waste or spill the insecticide."

Welcome

Lydia Mhlongo is more than happy to open her doors to them.

Just last year she had to nurse her son and his friend to recovery after they fell ill with cerebral malaria.

"My son was very sick, he couldn't even recognise us - he spent more than a week in hospital and had to spent another in bed here at home."

Primary health care is at the core of the malaria programme.

In Limpopo alone, 480 clinics equipped with diagnostic tests and combination drugs for those testing positive have been built.

For people like Lydia, indoor spraying is their only weapon against the disease.

Unemployment is very high here and they cannot afford repellents or insecticide-treated nets.

The South African government is not providing nets at all but has opted for indoor residual spraying.

History

South Africa had stopped using DDT in 1996. Until then the total number of malaria cases was below 10,000 and there were seldom more than 30 deaths per year.

But in 2000, the country saw malaria cases skyrocket to 65,000 and 458 people were killed.

Provincial health minister Seaparo Sekwati defends the use of DDT, saying it saves lives.

"We have decided that as South Africa, as a developing country, we are going to use the most accessible DDT which is also cost effective because we cannot go for expensive things which we cannot afford as a country.

"We are going to continue using DDT as it has worked and has worked for those developed countries in the past."

Last year only 89 deaths were recorded.

But the disease can never be fully eradicated without neighbouring countries also jacking up their malaria control programmes.

This led to the creation of the Lubombo Spatial Development Initiative, backed by the Global Fund to Fight HIV/Aids, Malaria and TB, which has led to an 83% and 67% drop in malaria cases in Swaziland and Mozambique respectively.

South Africa is also providing resources and technical training to Zimbabwe's southern Matabeleland province and assistance to Angola.

Richard Tren, Director of Africa Fighting Malaria, describes the malaria programme as one of the best in the region. He attributes this success to the fact that it is well funded and because the government has the freedom to decide on how to intervene.

"Countries like Tanzania, and Kenya are very reliant on donors. That means they basically have to do what the donors say they must do. Donors shy away from interventions like indoor residual spraying.

"They really force them to use insecticide-treated nets. That on its own is not going to control malaria or meet the MDGs."

If the regional programme is fully implemented, South Africa and its neighbours could be well on their way to achieving the millennium goal to halt and begin to reverse malaria cases by 2015. But the key is to sustain current projects.

BBC News