Cypermethrin and ivermectin resistance in field populations of Rhipicephalus sanguineus sensu lato (Latrielle, 1806) collected from dogs in south India

Abstract

The abuse of acaricides for control of Rhipicephalus sanguineus sensu lato ticks led to a strong selection pressure for acaricide resistance. Data on acaricide resistance in R. sanguineus s.l. populations from India is meager though veterinarians frequently report treatment failures. The present study was aimed to characterize the level of resistance in R. sanguineus s.l. against most commonly used drugs, cypermethrin and ivermectin in Andhra Pradesh, south India. Fourteen adult female tick populations were collected from naturally infested dogs at veterinary clinics, residence and stray dog in nine state municipal corporations/municipalities. Information on the history of dog treatment with acaricides was obtained by interviewing dog owners. The larval packet test (LPT) and larval immersion test (LIT) were used on the larvae of ticks to test for resistance to cypermethrin and ivermectin, respectively. Mortality data of each tick population was analyzed by probit analysis. Corresponding to the most susceptible population, thirteen (92.6%) and six (42.9%) tick populations were regarded as resistant to cypermethrin and ivermectin, respectively. The phenotypic level of cypermethrin (resistance ratios at LC50% varied from 1.55 to 13.29) and ivermectin (resistance ratios at LC50% ranged from 1.16 to 4.79) resistance varied distinctly between the populations. Additionally, all the populations were tested using PCR to demonstrate the frequency of the point mutation in sodium channel gene that corresponds with resistance of R. sanguineus s.l. to cypermethrin. A nucleotide substitution (T2134C) on domain III segment VI of the sodium channel gene was noticed in phenotypically resistant tick populations on DNA sequencing. Ivermectin resistance in the brown dog ticks is reported for the rst time from India.

Detection of ivermectin and fipronil resistance in Rhipicephalus sanguineus sensu lato in Maha Sarakham, Thailand

“…The RR of brown dog ticks to ivermectin in this study was similar to those recorded in Brazil (RR = 1.54–2.97) and India (RR = 1.16–4.79) [ 16 , 29 ] but lower than those recorded in Mexico (RR ≤ 30.5) and Argentina (RR = 1–18.33) [ 15 , 30 ]. These differences in resistance might be related to the frequency of acaricide exposure in each region.…”

An investigation of the acaricidal activity of benzyl alcohol on Rhipicephalus annulatus and Rhipicephalus sanguineus and its synergistic or antagonistic interaction with commonly used acaricides

“…The addition of BA to cypermethrin resulted in a synergistic effect with an LC 50 of 0.16 mL/L, whereas the LC 50 of cypermethrin alone was 1.78 mL/L. Similarly, Sunkara et al (2022) and Rodriguez‐Vivas et al (2017) found cypermethrin resistance in R. sanguineus populations obtained from dogs in South India and Mexico, respectively. Amrutha et al (2021) also reported resistance to deltamethrin in populations of R. sanguineus in South India.…”

Monitoring of evolution of resistance to commercial acaricidal products in Rhipicephalus sanguineus sensu lato (Latreille, 1806) (Acari: Ixodidae) from Goiânia, Goiás State, Brazil

“…27 Resistance developed by this ixodid to ivermectin was evidenced in Mexico, 28 and also in India, in addition to the fact that resistance to Deltamethrin and Cypermethrin was also observed in this country. 4,29 In view of this, an alternative measure to synthetic chemical acaricides, to be added to a rational integrated system of ticks control measures, 50 is the development of anti-tick vaccines. There are vaccines on the market (Bm86) with antigens related to intestinal membrane proteins of the cattle tick, however, they have low lethality at adult stages (20-30%) and are still costly for the producer.…”

“…Brazil, Uruguay, Argentina, Chile, Mexico, United States, Portugal, Spain, Italy, France, Switzerland, Mozambique, India, among others countries. [1][2][3][4] Despite parasitizing mainly domestic dogs, being the most prevalent tick on these hosts in urbanized areas of Brazil and other American countries, this ixodid can, however, parasitize other mammals, birds and reptiles, which partly explains its wide dispersion. [5][6][7] Different strains of R. sanguineus complex are involved in the transmission of various pathogens to their hosts, such as Babesia canis, B. gibsoni, B. caballi, Ehrlichia canis, Hepatozoon canis, Haemobartonella canis, Theileria equi, and Rickettsia spp.…”

“…6,[22][23][24][25] More recently, the development of tolerance or resistance to different acaricide bases in different populations of Rhipicephalus sanguineus has been reported in other locations around the world. 4,[26][27][28][29] The accomplishment of regional studies to monitoring the susceptibility or resistance of R. sanguineus to chemical acaricides is of fundamental importance to guide local communities in choosing more efficient acaricide products, with a view to the health of domestic dogs, the reduction of the environmental impact with the rational use of these toxic products, and the decrease in the occurrence of cases of emerging tick-borne diseases in humans.…”