Seasonal activity of ticks infesting domestic dogs in Bejaia province, Northern Algeria

Association between ambient temperature and mammalian-related injuries in Guangzhou, China, 2014-2019

BACKGROUND

Meteorological factors are associated with various health outcomes. However, it remains uncertain whether ambient temperature affects animal aggressive behaviors and causes mammalian-related injuries (MRI) in humans. The study aimed to examine the effect of daily mean temperature on MRI in Guangzhou, China.

METHODS

Individual cases of MRI were obtained from Guangzhou Injury Surveillance System during 2014-2019. A combination of a distributed lag nonlinear model and conditional quasi-Poisson regression, implemented within a time-stratified case-crossover design, was employed to evaluate the association between temperature and MRI. Subgroup analyses were conducted by sex, age group, education level, and types of mammals.

RESULT

This study included 24,206 MRI cases among which 89.7 % were caused by cats or dogs. We observed a nonlinear relationship between daily mean temperature and MRI. The impact of high temperatures was most pronounced on the current day and remained statistically significant on the next day. Compared with the reference temperature with a minimum risk of injuries (9.3 °C, approximately 2nd percentile of temperature), 75th percentile of temperature (27.4 °C) exerted the greatest relative risk (RR) of injuries (RR = 1.45, 95 % CI: 1.25-1.68) over lag 0-1 days. In subgroup analyses, the effects of high temperatures among males and females were similar. Individuals aged 15-34 years and 35-59 years were more susceptible to MRI at high temperatures compared to other age groups. The risk of injuries caused by cats or dogs consistently increased with high temperatures. We did not find significant impacts of low temperatures.

CONCLUSION

Short-term heat exposure plays an important role in the occurrence of MRI. The findings highlight the importance of enhancing public awareness regarding the high temperature-associated hazards posed by mammals. There is a need for enhanced regulations and measures on the management for cats and dogs to mitigate the harm caused in hot seasons.

Synopsis of the ticks of Algeria with new hosts and localities records

Background

Ticks are obligate hematophagous arthropods with a world-wide distribution that are extremely important not only in terms of human and animal health but also economically. In Algeria, information on tick species is scarce.

Methods

A systematic literature review was performed using online databases. The information extracted from the databases was was supplemented by information from an original study. Ticks were collected from various hosts and by flagging from January 2018 to December 2019.

Results

To date, in Algeria a total of 36 valid tick species belonging to two families have been recorded: (1) family Argasidae, with three Argas species and nine Ornithodoros species recorded; and (ii) family Ixodidae, with one Dermacentor species, three Haemaphysalis species, 10 Hyalomma species, four Ixodes species and six Rhipicephalus species recorded. The geographical distribution for each species was determined and listed. Eight new tick-host associations were recorded: four for Ixodes inopinatus sensu Estrada-Peña et al. 2014, one for Rhipicephalus bursa, one for R. turanicus, one for Hyalomma marginatum and one for Hy. lusitanicum. To our best knowledge, this study is the first to report the presence of I. inopinatus sensu Estrada-Peña et al. 2014 in Algeria. We also report here for the first time all tick species (Argasidae and Ixodidae) known to be present in Algeria.

Conclusion

This article represents a tool for students and scientists who work in the field of ticks and provides important new data on the distribution of ticks in Algeria.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05424-2.

Molecular detection of tick-borne pathogens in Rhipicephalus sanguineus sensu stricto collected from dogs in the steppe and high plateau regions of Algeria

Epidemiology and distributions of canine tick-borne diseases as well as their veterinary and zoonotic significance are poorly understood in Algeria. The present study describes a molecular investigation of important tick-borne pathogens in Rhipicephalus sanguineus sensu stricto collected from domestic dogs in steppe and high plateau areas of central and eastern Algeria. In total, 1,043 ticks were collected from 147 domestic dogs, including 756 ticks from 124 dogs in the steppe region of Djelfa, and 287 ticks from 23 dogs in the high plateau area of Bordj Bou Arreridj. Ticks were divided into 384 pools (309 pools from Djelfa and 75 pools from Bordj Bou Arreridj) and tested for genomic materials of Crimean-Congo hemorrhagic fever virus (CCHFV) as well as DNA for Anaplasma phagocytophilum, Anaplasma platys, Ehrlichia canis, Rickettsia spp., Babesia spp., and Hepatozoon spp. using PCR, sequencing and phylogenetic analysis. Hepatozoon spp. was most prevalent, with 160 positive pools (41.70%), and 12 of these were sequenced and identified as Hepatozoon canis. Babesia spp. was detected in 50 samples (13.0%), of which 11 were sequenced and identified as Babesia vogeli. A. platys and E. canis were detected in 92 (24.0%) and 15 (3.9%) of tested samples, respectively. Rickettsia spp. were detected in 24 (6.3%) samples, including 11 samples identified as R. massiliae, 6 samples identified as R. conorii conorii, and 7 samples could not be identified to species level. All 384 pools tested negative for CCHFV and A. phagocytophilum. In addition to detection of R. conorii conorii, R. massiliae, and E. canis, the present study provides the first molecular data for occurrence of A. platys, B. vogeli, and H. canis in Rh. sanguineus s.s. infesting dogs in Algeria. Further large scale studies should be conducted to better understand the epidemiology, distributions and importance of canine tick-borne pathogens in Algeria.

Molecular characterisation of Rhipicephalus sanguineus sensu lato ticks from domestic dogs in Nigeria

Rhipicephalus sanguineus is the most widely reported tick in the world. Molecular characterisation is important to verify its taxonomic status in the different parts of the world. In this study, we provide information on the molecular characterisation of R. sanguineus tick of dogs collected from Nigeria. Ticks were collected from 62 of 93 sampled dogs. The collected ticks were subjected to morphological identification with the aid of appropriate entomological keys. Deoxyribonucleic acid (DNA) was extracted from the most prevalent tick species (R. sanguineus) and was subjected to further molecular characterisation protocols. The partial mitochondrial 16S rRNA gene sequences (∼300 bp) were obtained from representative specimens. Data were statistically analysed using the chi‐square (χ²) test. Phylogenetic analysis was performed including different lineages of R. sanguineus (sl) from Africa, Asia, Europe and America, and other species belonging to the R. sanguineus ‘tropical lineage’ (R. linnaei) as well as Rhipicephalus turanicus and Ixodes ricinus. Results of this study showed that R. sanguineus was the most abundant ticks of dogs with a prevalence of 61.8% (68/110; 95% CI = 52.5–70.54), followed by Amblyomma variegatum (20.0%) and Haemaphysalis leachi (18.2%). The molecular analysis shows that they are genetically different from the temperate strains but closely related to those from other West African countries. There is a need to establish the vector competence of this common Nigerian dog tick.

A Survey of Potentially Pathogenic-Incriminated Arthropod Vectors of Health Concern in Botswana

Arthropod vectors play a crucial role in the transmission of many debilitating infections, causing significant morbidity and mortality globally. Despite the economic significance of arthropods to public health, public knowledge on vector biology, ecology and taxonomic status remains anecdotal and largely unexplored. The present study surveyed knowledge gaps regarding the biology and ecology of arthropod vectors in communities of Botswana, across all districts. Results showed that communities are largely aware of individual arthropod vectors; however, their 'potential contribution' in disease transmission in humans, livestock and wildlife could not be fully attested. As such, their knowledge was largely limited with regards to some aspects of vector biology, ecology and control. Communities were strongly concerned about the burden of mosquitoes, cockroaches, flies and ticks, with the least concerns about fleas, bedbugs and lice, although the same communities did not know of specific diseases potentially vectored by these arthropods. Knowledge on arthropod vector control was mainly limited to synthetic chemical pesticides for most respondents, regardless of their location. The limited knowledge on potentially pathogen-incriminated arthropod vectors reported here has large implications for bridging knowledge gaps on the bio-ecology of these vectors countrywide. This is potentially useful in reducing the local burden of associated diseases and preventing the risk of emerging and re-emerging infectious diseases under global change.

Importation of Ticks on Companion Animals and the Risk of Spread of Tick-Borne Diseases to Non-Endemic Regions in Europe

Increased human mobility elevates the risk of exposure of companion animals travelling with their owners or imported from other regions to tick attacks. In this study, we highlight the potential role of dogs and cats taken for tourist trips or imported animals in the spread of ticks and tick-borne pathogens. The Rhipicephalus sanguineus tick, which is a vector of numerous pathogens causing diseases in animals and humans, is imported most frequently from endemic areas to many European countries. Additionally, alien tick species with high epizootic and epidemiological importance can be imported on dogs from other continents. Companion animals play an even greater role in the spread of autochthonous tick species and transmission of tick pathogens to other animals and humans. Although the veterinary and medical effects of the parasitism of ticks carried by companion animals travelling with owners or imported animals are poorly assessed, these animals seem to play a role in the rapid spread of tick-borne diseases. Development of strategies for protection of the health of companion animals in different geographic regions should take into account the potential emergence of unknown animal tick-borne diseases that can be transmitted by imported ticks.

Hematological and Oxidative Status Parameters in Domestic Dogs Naturally Infested by Rhipicephalus Sp

The present study was aimed to evaluate hematological and oxidative stress parameters in domestic dogs infested naturally (n=10) by Rhipicephalus sp. to compare with non-infested dogs (n=10). All blood samples were collected from brachial vein into tubes EDTA for the hematological analysis such as red blood cells (RBCs), white blood cells (WBCs), hemoglobin (HGB) and platelets (PLT). Serum was rapidly separated after centrifugation and stored at -20 °C until it was used for malondialdehyde (MDA) and 2,2’-Azinobis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) inhibition measurements. HGB in non-infested dogs was significantly higher than in infested dogs (P<0.05). There was no significant difference in RBCs, WBCs and PLT between both groups (P>0.05). The mean of MDA concentration was high in infested dogs (0.92±0.62 nmol/ml) compared to non-infested dogs (0.75±0.25 nmol/ml). On the other hand, the percentage of ABTS inhibition was similar in both groups (P=0.71). High tick number seems significantly affected WBCs (P<0.0001) and HGB (P<0.001) in infested dogs. Concerning oxidative status, there was no significant differences (P>0.05) between low and high infested dogs, neither in the amount of MDA nor in the ABTS inhibition. In conclusion, infested dogs induced RBCs alterations, which coincided with the oxidative damage, as evidenced by MDA serum levels. Also, there was a relationship between the tick number in infested dogs and the hematological parameters.

Mitochondrial 16S rRNA gene analysis reveals occurrence of Rhipicephalus sanguineus sensu stricto from steppe and high plateaus regions, Algeria

The present study aims to perform comparative genetic characterization for R. sanguineus s.l. infesting Algerian dogs living in steppe and high plateau regions based on mitochondrial 16S rRNA gene sequencing and phylogenetic analysis. In total, 1043 ticks were collected from 147 infested dogs, including 756 ticks from 124 dogs in Djelfa and 287 ticks from 23 dogs in Bordj-Bou-Arreridj. All ticks were morphologically identified as R. sanguineus s.l., and 87 specimens were randomly selected for molecular analysis. Sequences obtained from selected ticks clustered with sequences of R. sanguineus s.l. from France, Germany, Portugal, and Spain, all of which belong to R. sanguineus s.s. The occurrence of R. sanguineus s.s. in Algeria is an interesting result given that most R. sanguineus in Africa cluster among the tropical lineage. This finding should prompt further investigation by exhaustive studies across Algerian territory. Such data can be useful to understand the dispersal route of R. sanguineus s.s. from Europe to North Africa, or whether their occurrence in Algeria is a result of historical biogeography.