Tiny assassin, we're coming for you

Ahead of the biennial South African Association of Veterinary Technologies conference in October, we take a look at important work being done on how DNA is tracking the tsetse fly’s commute in high risk corridors in South Africa. 

Think of Kruger or Hluhluwe-iMfolozi, and it's the Big Five that comes to mind. But right now, scientists from the Agricultural Research Council (ARC) and Onderstepoort are tracking a much smaller, far more dangerous predator across these borders: the tsetse fly. 

Known for spreading a devastating livestock disease called Nagana, the tsetse is a major threat to agriculture. To stop them, scientists first need to figure out exactly who they are and where they are going – and they are using some cool molecular biology to do it. 

Insect ancestry and facial recognition

Are South African tsetse flies mingling with flies from the rest of the continent, or are they a secluded local clan? To find out, researchers are looking at two things: wing morphometrics and mitochondrial COI markers. 

In plain English? They are combining physical profiling (measuring the intricate, microscopic vein patterns on a fly’s wing like a fingerprint) with ancestry DNA testing (reading the specific cellular barcodes passed down from the mother). The early data suggests something fascinating: South Africa’s tsetse flies might actually be completely isolated from the rest of Africa. 

The wildlife-to-farm commute

If these flies are an isolated clan, what are their daily flight paths? A huge portion of tsetse territory overlaps with our biggest nature reserves. To find out if these flies are commuting out of the parks to bite livestock on nearby farmlands, the ARC team is using a technique called metabarcoding. 

Instead of trying to physically track individual flies, metabarcoding allows scientists to analyse complex environmental DNA samples to map the exact movement – or flux – of these insects between wild animals and domestic herds. At the same time, ARC’s bioinformatics team is sequencing the DNA of resistant super-flies that survive insecticides to map out their genetic weaknesses. 

So, what is the ultimate endgame?

South Africa is without an official roadmap for managing Nagana. By mapping these microscopic flight paths and decoding the DNA of insecticide-resistant flies, researchers hope to design eco-friendly, surgical eradication strategies. That means no blanketing of regions with broad-spectrum chemicals, instead they are targeting problem populations that commute to nearby farms. Ultimately, it’s about using molecular data to protect the livelihoods of rural cattle farmers while keeping the delicate ecosystems of our most famous national parks completely intact.

The Celtic connection

You can't trace a microscopic fly's ancestry, sequence its resistance genes, or run complex environmental metabarcoding without world-class molecular tools.

To pull off this kind of high-level disease tracking, research facilities rely on rapid PCR technology. This is where Celtic Molecular Diagnostics steps in. Through its strategic partnership with YouSeq, Celtic Molecular Diagnostics designs, develops, and manufactures custom qPCR kits tailored for almost any molecular diagnostic application, including veterinary diagnostics, environmental monitoring and research applications, creating solutions that meet specific performance and workflow requirements.

Celtic Molecular Diagnostics is an official sponsor of the upcoming South African Association of Veterinary Technologies (SAAVT) Congress 2026 from 30 September to 01 October 2026 at the Krystal Beach Hotel in Gordon's Bay, Western Cape.