International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya.
Quantitative Veterinary Epidemiology, Wageningen University & Research, Wageningen, The Netherlands.
PLoS One. 2022 Aug 16;17(8):e0272865. doi: 10.1371/journal.pone.0272865. eCollection 2022.
Ticks and tick-borne diseases cause substantial economic losses to the livestock industry in sub-Saharan Africa. Mazao Tickoff is a novel bioacaricide developed for tick control and is based on the entomopathogenic fungus Metarhizium anisopliae sensu lato (s.l.) isolate ICIPE 7. To date, no randomized controlled study has been undertaken to demonstrate the efficacy of this bioacaricide in reducing natural tick infestation on cattle. To this end, this field trial is designed to evaluate the anti-tick efficacy of Mazao Tickoff on cattle in coastal Kenya compared to a standard chemical tick control protocol. In this prospective, multi-center randomized controlled trial, eligible herds will be randomized by the herd size to the intervention arm in a 1:1:1 ratio to either Triatix® (active ingredient: amitraz); Mazao Tickoff (active ingredient: M. anisopliae ICIPE 7); or placebo (excipients of the Mazao Tickoff), with a total enrollment target of 1,077 cattle. Treatments will be dispensed on Day 0 (defined individually as the day each animal receives the first treatment) and thereafter every two weeks until Day 182. Ticks will be counted on every animal in each herd (herds to be included have at least one animal bearing at least one tick on Day 0), and thereafter on bi-weekly intervals until Day 182. The primary efficacy assessments of Mazao Tickoff will be based on the mean percentage reduction in tick counts at each post-treatment follow-up visit compared to the placebo group and the Triatix® arm. Further, the effect of Mazao Tickoff on the prevalence of common cattle pathogens, Anaplasma marginale and Theileria parva, will be determined by assessing incidence and seroprevalence at four different time points. This protocol describes the first rigorous evaluation of the efficacy of Mazao Tickoff and its potential as a viable alternative non-chemical acaricide tool for tick control in Kenya and elsewhere.
在撒哈拉以南非洲，蜱虫和蜱传疾病给畜牧业造成了巨大的经济损失。Mazao Tickoff 是一种新型的杀蜱生物农药，用于蜱虫防治，其基础是昆虫病原真菌金龟子绿僵菌广义种（s.l.）分离株 ICIPE 7。迄今为止，尚未进行随机对照研究来证明这种生物杀蜱剂在降低牛自然蜱虫感染方面的功效。为此，本现场试验旨在评估 Mazao Tickoff 在肯尼亚沿海地区控制牛蜱虫方面的抗蜱虫功效，并与标准化学蜱虫防治方案进行比较。在这项前瞻性、多中心随机对照试验中，合格的牛群将根据牛群规模，通过随机分配到干预组，以 1:1:1 的比例分配到 Triatix®（有效成分：双甲脒）、Mazao Tickoff（有效成分：M. anisopliae ICIPE 7）或安慰剂（Mazao Tickoff 的赋形剂），总入组目标为 1077 头牛。在第 0 天（定义为每只动物接受第一次治疗的当天）开始进行治疗，此后每两周一次，直到第 182 天。将对每个牛群中的每只动物进行蜱虫计数（包括的牛群至少有一只动物在第 0 天有至少一只蜱虫），此后每两周一次，直到第 182 天。Mazao Tickoff 的主要疗效评估将基于与安慰剂组和 Triatix®组相比，每个治疗后随访时蜱虫计数的平均百分比减少情况。此外，通过在四个不同时间点评估 Anaplasma marginale 和 Theileria parva 等常见牛病原体的发病率和血清流行率，来确定 Mazao Tickoff 对它们的影响。本方案描述了首次对 Mazao Tickoff 的功效进行严格评估，以及其作为肯尼亚和其他地区可行的非化学杀蜱替代工具的潜力。
