KAMPALA, UGANDA — In a significant stride toward better livestock management, NARO scientists recently successfully completed field trials for the novel anti-tick vaccine-NAROVAC1. With tick infestations causing substantial economic losses and health issues for both animals and humans, this trial could be a game-changer for farmers across the region.
The trials, conducted across various agro-ecological zones, involved over 300 cattle from farms in Mbarara, Ibanda, Masindi, Apac and Nabilatuk ditricts. Researchers monitored the vaccine’s safety and effectiveness against 3 major tick species including Brown-Ear tick (Rhipicephalus appendiculatus), African blue tick (Rhipicephalus decoloratus) and Tropical Bont tick (Amblyomma variegatum).
“The Subolesin-based vaccine has proven to be safe and effective,”
Dr. Swidiq Mugerwa, Deputy Director General-Research Coordination said
We achieved upto 93.2% effectiveness in reducing tick infestations between 167 and 196 days post-vaccination.
Uganda, ticks and tick-borne diseases (TBD) cost the agricultural sector over $1.1 billion annually. These pests are not just a nuisance; they threaten livestock health and farmers’ livelihoods. Cattle are central to Uganda’s economy, providing milk, meat, and labor. However, the rising incidence of ticks poses a severe threat, as diseases like East Coast fever and babesiosis can decimate herds, leading to financial ruin for farmers.
The results are significant. The overall integrated vaccine effectiveness was estimated at 75% – 99%, showing a strong capacity to reduce tick populations and, consequently, the risk of tick-borne diseases and associated health complications in cattle. “This vaccine not only helps prevent disease but also lessens the financial burden on farmers who currently rely on expensive and often harmful acaricides,” Dr. Mugerwa added.
Dr. Kabi Fredrick, the Project Principle Investigator also emphasized the broader implications of the vaccine:
With a personalized design based on regional tick genotypes, this approach enhances its effectiveness. By targeting local tick species, we can better control infestations and improve cattle health
The trial is particularly timely as Uganda grapples with rising acaricide resistance. Farmers have increasingly turned to chemical treatments, which can lead to environmental harm and health risks.
The overuse of chemical acaricides has created resistant tick populations, making it harder for farmers to protect their cattle,
This vaccine provides a sustainable solution to a pressing problem
The research team aims to submit their findings for regulatory approval soon. If successful, the vaccine could be commercially available in the near future. “This is a crucial step for us,” Dr. Kabi explained. “We are eager to see this vaccine registered so that farmers can start benefiting from it.”
The potential impact of the Subolesin vaccine extends beyond agriculture. Tick-borne diseases can also affect human populations, increasing the urgency for effective control measures. “Addressing tick infestations not only safeguards livestock but also protects public health,” Dr. Mugerwa said. “Reducing the risk of diseases like Crimean-Congo Hemorrhagic Fever is essential for both human and animal health.”
As Uganda moves closer to the commercialization of this innovative vaccine, the hope is palpable among farmers and researchers alike. “The Subolesin vaccine could significantly improve the livelihoods of farmers and enhance cattle health across the region,” Dr. Mugerwa concluded.
As far as safety is concerned, the vaccine is not a potential allergen; is easily degraded and metabolized in the body; is not excreted in the mammary glands of the animal; and does not alter the milk quality; leading to the conclusion that the administration of the trial vaccine is not associated with food safety risks to the consumer of animal products obtained from vaccinated cattle.
In addition, the absence of subolesin protein bands in dung is suggestive that the vaccine is easily degraded and metabolized in the body of the animal, preventing its carry-over into dung and hence alleviating possibilities for its release into the environment. This, therefore, demonstrates that the trial vaccine is safe to the environment.
This subolesin-based vaccine does not affect normal body functions; haematological picture; organ structure and functionality; as well as reproductive performance; leading to the conclusion that the administration of trial vaccine is safe for the animal. With its promising results and potential for widespread adoption, the Subolesin vaccine is a ray of hope in the fight against ticks and tick-borne diseases in Uganda and beyond.