(Original source: The New Vision- Uganda's Leading Website (www.newvision.co.ug/) - 5/05/08)

Scientists Screen Reptiles to Trace Sleeping Sickness.

Kikonyogo Ngatya
Kampala

Scientists have started screening crocodiles, monitor-lizards, snakes and other reptiles to establish whether they are reservoirs for sleeping sickness and nagana disease parasites countrywide.

This follows a new study which found that domestic animals are reservoirs for sleeping sickness. The veterinary doctors have made recommendations based on this study to the Government to vaccinate all goats, pigs, cattle and sheep. sleeping sickness affects people, while nagana affects animals.

The reptile screening is on realisation that the animals harbour sleeping sickness parasites even though they do not get sick themselves. However, the disease is picked by tseflies bites and passed on to people.

Dr Loyce Okidi, the head of Sleeping Sickness Research Programme at the National Livestock Resources Research Institute (NaLIRRI) said their preliminary observations indicate that the reptiles offer blood meals to tsetse flies in the wild.

The diseases are transmitted by the flies when they suck blood from an infected host.

"Although no study has established that these parasites can thrive comfortably inside the reptiles, we are treating them suspiciously," she noted.

Okidi said their studies have indicated that there is a sharp increament in the river line tsetse flies population in almost all parts of the country's rivers and drainage network. She said it was possible that the reptiles could be playing a role in the spread of the flies following the River Nile, Kagera River Basin and Lake Kyoga to areas where they had not been recorded in the last two decades.

"The study follows an overwhelming tsetse flies population increase in the country. Over 60% of the country is now endemic. This has prompted an upsurge in sleeping sickness and nagana diseases in regions where it had not previously recorded.

Researchers said there was increased sleeping sickness and nagana cases in the Central Region, Northern and Eastern Uganda. More people are dying of the disease in rural areas when they fail to report to hospitals early enough when they self-medicate at home, confusing the disease for malaria.

Okidi said from Busoga region, the disease has spread to Apac, Amuria, Kaheramaido, Tororo and parts of Soroti district. The riverine species, Glossina f fuscipes and savanna adapted species (Glossina morsitans, G. pallidipes) were prevalent."

They have adapted extensively to the vast savanna grasslands in the cattle corridor. The corridor supports Uganda's livestock herd and wild animals. It stretches from Rakai district in southwestern Uganda to Nakapiripirit in Karamoja region.

Uganda's vulnerability is also caused by the geographical location on a plateau tilting northwards. The rivers that flow across the country make the insects spread much easier.