Let’s not drop guard, January disease is still lurking out there
THE metaphorical statement ‘We have scorched the snake, not killed it…’ that William Shakespeare uses to sum up Macbeth’s potentially explosive situation in the play Macbeth (Act 3, Scene 2) just after he murders Banquo, aptly describes the situation we face as a country in our push to eradicate January disease (Theileriosis).
While we revel in the successes that we have scored so far in containing the scourge, it is vital to remember that there are still active pockets of the problem that can easily explode and once again plunge us back into that unforgettable era that saw us losing cattle in the region of more than half a million or so to tick-borne diseases, particularly Theileriosis, commonly known as January disease.
The disease earned itself the name January disease because it is common between December and March although of late it has come to occur all year-round.
The highest number of cases of the disease, however, tends to be recorded in January when traditionally the rainfall activity will be high.
It is caused by protozoa called Theileria parva bovis, which destroys white blood cells in the lymphatic system and the lungs.
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, the disease spreads.
In the last few years, nearly all parts of the country have been affected including in areas in the drier areas where usually ticks do not survive.
As the country stands on the threshold of yet another fresh summer season, the possibilities of the disease making a comeback are very firm given that a number of sporadic outbreaks have been reported in different parts of the country in recent times.
Latest such reports are coming from Guruve in Mashonaland Central province where farmers say they are at risk of losing all their animals if no urgent action is taken to contain the situation.
The Department of Veterinary Services (DVS) has been actively involved in the fight to save the national herd and even introduced the strict 5-4-4 dipping schedule in which farmers are expected to dip their cattle after every five days then after every four days.
Government on the other end introduced the tick grease programme that allowed farmers to get over 2 million kilogrammes of tick grease distributed to stock owners countrywide.
Experts say regular dipping helps to intensify the killing of nymphs before they grow into adults and ensures that animals are totally soaked for best results.
As the country enters the 2023/24 rainfall season, it is therefore critical for farmers to practise intensive dipping and apply tick grease thereafter.
This treatment has since proved effective with mortalities dropping significantly in a development that even saw the national herd recording some growth to the current 5,6 million.
DVS went further to rehabilitate 500 plunge dips that had been lying idle.
They now have over 4 000 dip tanks in use countrywide while Government also drilled boreholes close to each dip tank to ensure there are no water shortages to frustrate the dipping efforts.
It is refreshing to note that Government did not end there but went on to revive the production of the Theileriosis vaccine BOLVAC, which was first produced by Zimbabwe’s Central Veterinary Laboratory (CVL) in 1989 using Zimbabwe’s own Theileria parva vaccine strain, isolated from Boleni Farm in Goromonzi district, hence the name BOLVAC vaccine.
Production of the BOLVAC vaccine was gradually discontinued in the late 1990s mainly due to high technical staff turnover and inadequate financing.
A total of 20 000 doses of BOLVAC vaccine was produced in August 2022, while a subsequent batch of 92 000 doses were produced in December 2022, which marked a successful breakthrough after several years of hard work.
The country can produce vaccines against three out of the four major tick-borne diseases (TBDs) prevalent in the country.
With this production capacity, the country is now ready to roll-out its Integrated Ticks and Tick-Borne Disease Control Strategy (ITTBDCS) composed of three main components namely dipping, acaricide resistance monitoring and the use of TBD vaccines.
All these efforts can, however, go to nought if farmers do not play their part to compliment Government through working with DVS.
Farmers need to follow dipping schedules religiously and respond positively if there are vaccination programmes being rolled out.
It is a fact that ticks cannot be totally eradicated but the successful suppression of their activities stems from the full implementation of all prescribed tick containment measures.
It is a fact that cattle share pastures but there is no guarantee that they are all clean in terms of carrying ticks on their bodies, which later spread to new hosts upon leaving their initial carriers.
The situation is also exacerbated by the fact that the bulk of the cattle are owned by communal farmers who do not have the capacity to either establish their own dipping structures or paddocks to avoid sharing pastures so the problem will remain a time bomb awaiting detonation.
At the moment there is no vaccine for the treatment of Theileriosis but there are tools that can be used to prevent an incursion into cattle herds.
The only meaningful solution at the moment is compliance to dipping and vaccination programmes and nothing else.
In fact, farmers can help their cause through the adoption of general biosecurity principles such as avoiding bringing in animals from known hotspots into their herds, as this provides a platform for the transfer of the pest from one animal to the other.
In the event that a farmer has imported animals from another region, the idea of quarantining them and intensively dipping them while applying tick grease or even vaccinating them, is not a bad one.
The farmer should have the confidence to use acaricides to minimise the tick burden among his animals and graze susceptible pastures with other species.
In some cases, the farmer can realise his mistake when its already late but still has to act to ensure the affected animals are properly taken care of.
The farmer has to desist from stressing the animals suspected of being infected with January disease to prevent compromising the movement of oxygen in their bodies any further.
Some of the measures farmers can use include avoiding too much movement and ensuring that the animals have enough water and good feed availed to them.