1 The little pigs and the big bad trypanosome Lucas J Cunningham

2 African Trypanosomiasis (Sleeping Sickness) Neglected Tropical Diseases, fatal if untreated 66 million people at risk in 36 African countries Single cell parasites called trypanosomes Transmitted by the bite of a tsetse fly Causes serious disease in animals Animal African Trypanosomiasis is responsible for a loss of U.S. $4.5 billion per year across sub Saharan Africa m_evasion_in_Trypanosoma_brucei

3 Importance of Human African Trypanosomiasis (HAT) Elimination 2020

4 African Trypanosomiasis Images: South Sudan Gambiense (chronic) sleeping sickness Rhodesiense (acute) sleeping sickness There are three species in the brucei group Trypanosoma brucei gambiense Trypanosoma brucei rhodesiense Trypanosoma brucei brucei

5 Can animals be a reservoir for gambiense? Past experiments have shown that pigs can be readily infected with gambiense sleeping sickness Recently more importance has been placed on the possibility of animal reservoirs influencing the transmission of the disease

6 Pig Sampling in Uganda Rhodesiense sleeping sickness Gambiense sleeping sickness DRC South Sudan

7 Pig sampling method

8 Analysis of pig blood for trypanosomes General test for species of interest Highly sensitive Targets an area of DNA with 10,000 copies per parasite Specific tests for species limited Targets an area of DNA with 1 copy per parasite

9 766 pigs were screened with the general test SiteTotal pigsInfected% infected Wiliffi Duku Tondolo Ngalabia Muttee Drimveni Inia Perego Opiro Moipi Kendi Goopi Kuleni Results 3.26% infection of T. brucei sl overall Arua Moyo 25 out of 400 were infected, 6.25% in Arua

10 Map

11 Do we have the big bad trypanosome? 25 positive samples re-screened for gambiense infections So far none of the pigs appear to be positive for the big bad trypanosome, this could be good news for the farmers But… Not all the tests have been finished, issue with sensitivity, plus the pigs still have animal trypanosomiasis

12 Conclusions 25 out of 766 pigs positive for trypanosomes of interest 20 out of 25 cases came from just two sample sites The issue with the sensitivity needs to be ruled out Secondary tests will need to follow to determine exact species present Why is Arua a hot spot and why isn’t Moyo? Is the big bad trypanosome still at large, not yet concluded

13 Thanks to: Stephen Torr (LSTM and Warwick NTD) Jessica Lingley (LSTM, Vector Group) Ugandan field technicians Ugandan vets Ugandan farmers Lee Haines (LSTM, Vector Group) Johan Esterhuizen (LSTM, Vector Group) Inaki Tirados (LSTM, NTD) Hannah Betts (LSTM, Vector Group) Liam Morrison (Roslin Institute, University of Edinburgh)

14 Impact of finding gambiense in pigs Target and screen animals- requires more accurate field diagnostics Identifying areas of transmission- disease is very focal, mass screening of the flies for the parasite maybe in conjunction with human and animal screening Integration of controls- will probably require a number of control strategies to eliminate the disease Disease eradication challenging