In the last few years, Zimbabwe has lost around half a million cattle to the tick-borne disease, theileriosis, better known as January disease, or in our study areas as ‘cattle covid’. This loss has had a huge impact on people’s livelihoods and their ability to farm. The severe draft power shortages across our study sites are as a result of animals having died or being sick and weak. The government has announced a ‘war on January disease’ for 2023.
Changing disease and vector ecologies
Theileriosis is spread by the brown tick (Rhipicephalus appendiculatus) and results in a swelling of the lymph nodes, running eyes, rough skin and loss of appetite and later almost certain death, especially with older, weaker animals. In periods of relatively good rainfall, as has been experienced certainly in parts of the country, tick populations explode and if they are not controlled through dipping, then the disease spreads.
In the last few years, nearly all parts of the country have been affected including in areas in the notionally drier areas where usually ticks do not survive. Climate change and animal disease is a big topic worthy of another blog, but there are important impacts, especially as weather events become more extreme, with big downpours resulting in sudden increases in tick populations as grass grows rapidly. A new distribution of tick populations and associated population dynamics – both over time and space – is being seen leading some to speculate that there may be new tick species carrying the disease. New selection pressures also change the vector and in turn the disease, making theileriosis today very different to before.
There has been much research on theileriosis and the brown tick in Zimbabwe and southern Africa more broadly. It should be an easy disease to control and indeed in the past it was so. The regular dipping programmes that were instituted across the country since colonial days kept the tick and so the disease at bay. Occasionally there were new outbreaks, but they were soon under control. The recent devastation of cattle populations is very different, and the Veterinary Department and ministers of agriculture are constantly beseeching people to dip, whether through the conventional immersion dip or through spray dipping.
As the officials point out it’s important to have the right chemicals, to ensure that animals are properly soaked, to add tick grease to parts of the body where ticks attack that are not usually dipped (such as ears) and to increase dipping frequency if the disease emerges. The 5-5-4 dipping regime is usually recommended, with dips spaced five, then four days apart. But it isn’t working and although the government is investing in vaccine development, with 20,000 already being tested, this is a costly alternative to vector control.
Why is January disease so bad these days? Some hypotheses from the field
So, what is going on? Discussions with livestock keepers as well as Vet department officials highlighted a number of hypotheses:
- The tick vectors are much more widespread and prevalent, with tick challenge high in nearly all areas. This is the result of periods of high rainfall in recent seasons with lots of grass growing. Following land reform, there is more grass, so more ticks in more places where people’s animals graze, resulting in a new distribution of ticks and disease.
- With the new configuration of land use following land reform, there are more animals spread across the country, but few dips especially in the resettlement areas. Along with the relaxation (or actually lack of implementation) of dipping regulations, animals are dipped infrequently and often not thoroughly.
- Some argue that the dip chemicals are not as good as they were with some being ‘fake’ and many being adulterated, although importers and manufacturers and Vet officials deny this. With the lack of foreign exchange, government has had to import dip chemicals from a number of sources. Senior officials in the Vet department have in the past bemoaned the lack of quality control. Whether it is the chemical or its mixing or application remains unknown, but this remains a possibility as fake drugs and chemicals are widely available in agro-supply stores (we visited one in Chiredzi and the very informed shop assistant pointed to which was which as we enquired about dipping chemicals. Not surprisingly the low efficacy alternatives were much cheaper and as he admitted the ones that sold most).
- Infrequent dipping and misapplication of dips may have resulted in resistance to dip chemicals (acaracides) by the ticks. Compared to the heavily grazed communal areas, ticks survive better in the new resettlements. In the past it was the commercial farms that suffered the disease most, but now it’s widespread. Grazing animals are exposed to ticks that survive in refuges and spread fast when sudden rainfall occurs. Others argue that there are new vectors among the wider array of ticks found in these grazing environments, extending the range of tick vectors.
- The mixing of breeds in both the communal and resettlement areas that resulted from the dispersal of commercial breeds across the country following land reform has probably meant less overall resistance to ticks and tick-borne disease. Hardy, small Mashona cattle could survive nearly anything, but this is less the case with exotic crosses, resulting in declining resistance in the population. With some investing in pure breeds as they stock their A2 farms – many succumb very quickly as farmers explained.
The problem is that these all remain conjectures, we don’t really know what’s happening. There are complex questions of evolutionary ecology, the economics and regulation of veterinary chemicals and ones of investment (in dipping infrastructure) and farmer (and veterinary) practice. What is clear is that livestock keepers and veterinarians are facing a very different challenge to before and are ill-equipped to respond.
Local response and innovation
While these questions need answering by some sustained research (which as far as I am aware is not happening at least to the extent needed given the national disaster unfolding), what are people doing now? Farmers we interviewed last year were desperate. Some had lost their whole herd; others had sick animals and were expecting the same. Those selling were getting pathetic prices, with traders coming to collect sick animals for a pittance. Cattle are vital assets – for ploughing, transport, manure, milk, meat and so on – and have great cultural and social value – as savings, foci for sharing, exchanges for bridewealth and so on, so this sort of loss is devastating.
The overall statistics that Zimbabwe has lost half a million animals worth USD$150 million over the last four years are shocking. But this still does not compute with the real consequences of loss of animals by individual households. Those we talked to did not know how they would cultivate. Many had reverted to farming just their small pfumvudwa (no till) plot, but that they said was insufficient to survive off and in the resettlement areas with around five hectares of arable land it meant that most of it was left as fallow if tractors could not be hired (see last blog). The result of course was more ticks in fallow fields and the cycle repeats itself.
As ever though Zimbabwean farmers do not give up. We discovered a huge amount of detailed epidemiological knowledge and an array of innovative practices. Some had become specialists in developing concoctions for giving to sick cattle, and they claimed it worked. One farmer had lost no animals at all, yet his neighbours had lost many. In the absence of support from elsewhere, indigenous veterinary practice had exploded. All sorts of remedies were suggested. They included feeding sick animals chibuku beer, giving them cooking oil (or combinations of beer and oil, soaking medicinal plants for infusions and administering smoke from certain plants.
Livestock keepers also had views on how to treat animals with available drugs. One had begun sharing his prescription through local WhatsApp groups. It was a complex combination of Hitet, Butachem and several antibiotics given in sequence after preventing animals from drinking. Once the treatment started extra molasses and multivitamins were offered to boost strength, he explained. He swore by it as an effective solution. It required rigorous timely application, and he complained that others were not following it well, berating the veterinarians for not experimenting and only following the standard prescriptions. As he put it, “you have to try different things out, diseases change, we cannot just follow the standard ways – that’s the colonial mindset.” Others had got dismayed by the locally available medicines and had imported alternatives from South Africa. They were expensive, headteacher observed, but they were worth it, as all his animals had survived.
A new veterinary response?
Simply beseeching people to dip properly or to administer drugs in line with recommendations is all well and good, but actually people were having to improvise and develop alternatives to the standard veterinary department recommendations. Rather like in the case of human COVID-19, the efficacy of some could be questioned, but currently we don’t know and a more collaborative enquiry into what works and doesn’t and why is urgently needed.
Local treatments give a sense of control and some hope in a desperate situation. Simply arguing, as a senior government vet did to us, that the problem lay in people’s lack of education and inability to follow recommendations, misses the point. What is needed is more research into the hypotheses outlined above, together with livestock keepers who have been living with the disease. And crucially in an engaged participatory way, taking seriously local understandings of tick ecology, livestock disease patterns and disease treatments.
Only then will a more effective veterinary response emerge. The January disease being faced now is very different to what was faced before – in terms of epidemiology as well as social-ecological dynamics – and new thinking is needed. Hoping that a tech-fix vaccine will solve the problem is insufficient.
This blog was written by Ian Scoones and first appeared on Zimbabweland