Surveys of Canine Filarioids In Nigeria: The Path Travelled and the Way Forward

Filarioid worms infecting dogs have recently received increased attention globally because of their zoonotic potential. In Africa and, particularly, in Nigeria, however, where there is preponderance of the risk factors for vector-borne diseases transmission, there are few reports of the disease in the canid and felid definitive hosts, the wild/domestic reservoirs and humans. Thus, the epidemiology of the disease in Nigeria remains sketchy and needs to be investigated. A retrospective analysis of reported canine filarioids in Nigeria was undertaken with the view to highlight what has been done and reported, existing gaps in knowledge, what needs to be done to bridge the gap and possibly how it could be done. Thirteen published works on canine filarioids using classical laboratory methods in Nigeria, reported the finding of Dirofilaria immitis (0.4–15.1%), Dirofilaria repens (0.1–9.4%), Acanthocheilonema reconditum (0.4–9.2%) and a case of A. dracunculoides in an unspecified dog population. In most instances, the species identification of the filarioids reported was not conclusive due to limitation of the diagnostic methods employed. No human infection due to any zoonotic canine filarioid has been reported in Nigeria. Suggestions for prospective filarioids research in Nigeria were made. Keywords: Filarioids, dog, zoonosis, diagnosis, Nigeri

Demonstration of vermicules of Babesia species in haemolymph smears of Amblyomma variegatum in Nigeria

The present study was conducted to investigate the presence of developmental stage (s) of Babesia species in Amblyomma variegatum. A total of 137 Amblyomma variegatum ticks (85 males and 52 females) were examined by haemolymph smears. Out of the examined male ticks, there were 41 nymphs and 44 adults. The female ticks were 23 nymphs and 29 engorged adults. Sixteen adult males and nine nymphs were positive for vermicules of Babesia species but only eight femalesshowed structures similar to Babesia vermicules. The present study recommends conducting molecular and experimental studies to confirm the type of Babesia parasite in Amblyomma variegatum tick

Molekularni dokaz filarija u pasa u Nigeriji, zapadna Afrika

The filarioid worm Dirofilaria repens has long been reported in dogs in Nigeria. Recent studies however, did not only report increased prevalence of D. repens but also the presence of Dirofilaria immitis. The classical diagnostic methods used in these studies have low sensitivity. Therefore, we screened 197 canine blood samples from seven states in Nigeria, using a highly sensitive and specific High Resolution Melt Real Time PCR and sequencing, to determine the prevalence and species of filarial worms infecting Nigerian dogs. Only one (0.5%) of the 197 samples screened was positive and showed a melt curve similar to Acanthocheilonema reconditum. Nevertheless, the sequence of this positive sample had only 94% similarity to its first GenBank match, a A. reconditum (JF461460.1). This could be a new filarioid species or a variant of an existing species and deserves further investigation. The low prevalence reported herein is in discrepancy with previous reports that showed the frequent presence of canine filariasis in Nigeria. A large scale survey is needed of filarioids infecting dogs in Nigeria, using highly sensitive and specific methods, to identify the present species and provide a baseline data on their national prevalence and geographic distribution.O parazitu Dirofilaria repens u pasa u Nigeriji odavno postoje podaci. Novija istraživanja, međutim, ne pokazuju samo povećanu prevalenciju D. repens nego i prisutnost D. immitis. Klasične dijagnostičke metode primijenjene u ovom istraživanju imaju nisku osjetljivost. Stoga smo ispitali 197 uzoraka pseće krvi iz sedam pokrajina u Nigeriji koristeći se visokoosjetljivom i visokospecifičnom metodom High Resolution Melt Real Time PCR i sekvenciranjem kako bismo odredili prevalenciju i vrste filarija koje invadiraju pse u Nigeriji. Samo je jedan (0,5 %) od 197 uzoraka bio pozitivan i pokazao je krivulju sličnu krivulji za parazita Acanthocheilonema reconditum. Sekvencija tog pozitivnog uzorka imala je samo 94 % sličnosti s prvom podudarnom sekvencijom iz banke gena, A. reconditum (JF461460.1). To bi mogla biti nova vrsta filarija ili varijanta postojećih vrsta i zahtijeva daljnja istraživanja. Opisana niska prevalencija u ovome radu odstupa od prijašnjih izvješća koja pokazuju čest nalaz psećih filarija u Nigeriji. Kako bi se dokazale postojeće vrste i pružili referentni podaci o prevalenciji i zemljopisnoj raširenosti filarija u pasa u Nigeriji, potrebno je provesti opsežnija istraživanja

Effects of Parasitic Infections on Erythrocyte Indices of Camels in Nigeria

This study was conducted to determine the prevalence and effect of parasitic infection on erythrocyte indices in trade camels slaughtered in Maiduguri, Nigeria. Two hundred adult one humped camels comprised of 87 (43.5 %) males and 113 (56.5 %) females were examined for helminths and hemoparasites at their slaughter time according to the standard procedures. An overall prevalence of 79 % for single and mixed infections was observed. Examination of faecal samples from camels shows 82 (41 %) were harbouring different nematodes, mostly Strongyle, Strongyloides and Hemonchus species. Buffy coat and thin smear examination of blood samples showed Babesia and Anaplasma species. More females (44.5 %) than males (34.5 %) were positive for various parasitic infections. But the percentage was not statistically significant (P > 0.05). Packed cell volume (PCV), mean haemoglobin concentration (MCH), mean corpuscular haemoglobin concentration (MCHC) and red blood cell counts were significantly (P < 0.01) affected in the infected camels compared to the non-infected ones. Parasite infection in camels leads to macrocytic anaemia

Detection of Alpha- and Betacoronaviruses in Frugivorous and Insectivorous Bats in Nigeria

The rise of bat-associated zoonotic viruses necessitates a close monitoring of their natural hosts. Since the detection of severe acute respiratory syndrome coronavirus (SARS-CoV), it is evident that bats are vital reservoirs of coronaviruses (CoVs). In this study, we investigated the presence of CoVs in multiple bat species in Nigeria to identify viruses in bats at high-risk human contact interfaces. Four hundred and nine bats comprising four bat species close to human habitats were individually sampled from five states in Nigeria between 2019 and 2021. Coronavirus detection was done using broadly reactive consensus PCR primers targeting the RNA-dependent RNA polymerase (RdRp) gene of CoVs. Coronavirus RNA was detected in 39 samples (9.5%, CI 95%: [7.0, 12.8]), of which 29 were successfully sequenced. The identified CoVs in Nigerian bats were from the unclassified African alphacoronavirus lineage and betacoronavirus lineage D (Nobecovirus), with one sample from Hipposideros ruber coinfected with alphacoronavirus and betacoronavirus. Different bat species roosting in similar or other places had CoVs from the same genetic lineage. The phylogenetic and evolutionary dynamics data indicated a high CoV diversity in Nigeria, while host switching may have contributed to CoV evolution. Robust sentinel surveillance is recommended to enhance our knowledge of emerging and re-emerging coronaviruses

Effects of Tectonics and Large Scale Climatic Changes On the Evolutionary History of \u3ci\u3eHyalomma\u3c/i\u3e ticks

Hyalomma Koch, 1844 are ixodid ticks that infest mammals, birds and reptiles, to which 27 recognized species occur across the Afrotropical, Palearctic and Oriental regions. Despite their medical and veterinary importance, the evolutionary history of the group is enigmatic. To investigate various taxonomic hypotheses based on morphology, and also some of the mechanisms involved in the diversification of the genus, we sequenced and analysed data derived from two mtDNA fragments, three nuclear DNA genes and 47 morphological characters. Bayesian and Parsimony analyses based on the combined data (2242 characters for 84 taxa) provided maximum resolution and strongly supported the monophyly of Hyalomma and the subgenus Euhyalomma Filippova, 1984 (including H. punt Hoogstraal, Kaiser and Pedersen, 1969). A predicted close evolutionary association was found between morphologically similar H. dromedarii Koch, 1844, H. somalicum Tonelli Rondelli, 1935, H. impeltatum Schulze and Schlottke, 1929 and H. punt, and together they form a sister lineage to H. asiaticum Schulze and Schlottke, 1929, H. schulzei Olenev, 1931 and H. scupense Schulze, 1919. Congruent with morphological suggestions, H. anatolicum Koch, 1844, H. excavatum Koch, 1844 and H. lusitanicum Koch, 1844 form a clade and so also H. glabrum Delpy, 1949, H. marginatum Koch, 1844, H. turanicum Pomerantzev, 1946 and H. rufipes Koch, 1844. Wide scale continental sampling revealed cryptic divergences within African H. truncatum Koch, 1844 and H. rufipes and suggested that the taxonomy of these lineages is in need of a revision. The most basal lineages in Hyalomma represent taxa currently confined to Eurasia and molecular clock estimates suggest that members of the genus started to diverge approximately 36.25 million years ago (Mya). The early diversification event coincides well with the collision of the Indian and Eurasian Plates, an event that was also characterized by large scale faunal turnover in the region. Using S-Diva, we also propose that the closure of the Tethyan seaway allowed for the genus to first enter Africa approximately 17.73 Mya. In concert, our data supports the notion that tectonic events and large scale global changes in the environment contributed significantly to produce the rich species diversity currently found in the genus Hyalomma

Straw-colored fruit bats (Eidolon helvum) and their bat flies (Cyclopodia greefi) in Nigeria host viruses with multifarious modes of transmission

8 páginas, 4 figurasBackground: Bat flies (Diptera: Hippoboscoidea: Nycteribiidae and Streblidae) are increasingly appreciated as hosts of "bat-associated" viruses. We studied straw-colored fruit bats (Eidolon helvum) and their nycteribiid bat flies (Cyclopodia greefi) in Nigeria to investigate the role of bat flies in vectoring or maintaining viruses. Methods: We captured bats and bat flies across northern Nigeria. We used metagenomics to identify viruses in 40 paired samples (20 flies from 20 bats). We characterized viruses using genomic and phylogenetic methods, and we compared infection frequencies in bats and their bat flies. Results: In 20 bats, we detected two individuals (10%) infected with eidolon helvum parvovirus 1 (BtPAR4) (Parvoviridae; Tetraparvovirus), previously described in Ghana, and 10 bats (50%) with a novel parvovirus in the genus Amdoparvovirus (Parvoviridae). The amdoparvoviruses include Aleutian disease virus of mink and viruses of other carnivores but have not previously been identified in bats or in Africa. In 20 paired bat flies (each fly from 1 bat) all (100%) were infected with a novel virus in the genus Sigmavirus (Rhabdoviridae). The sigmaviruses include vertically transmitted viruses of dipterans. We did not detect BtPAR4 in any bat flies, and we did not detect the novel sigmavirus in any bats. However, we did detect the novel amdoparvovirus in 3 out of 20 bat flies sampled (15%), including in 2 bat flies from bats in which we did not detect this virus. Discussion: Our results show that bats and their bat flies harbor some viruses that are specific to mammals and insects, respectively, and other viruses that may transmit between bats and arthropods. Our results also greatly expand the geographic and host range of the amdoparvoviruses and suggest that some could be transmitted by arthropods. Bat flies may serve as biological vectors, mechanical vectors, or maintenance hosts for "bat-associated" viruses.This project was funded by the University-Wisconsin, Madison John D. MacArthur Professorship Chair (to T.L.GPeer reviewe

Prevalence and diversity of Gastro-intestinal parasites in captive wild animals in Northern Nigeria

9 páginas, 2 tablasCopro-parasitological survey of 217 captive wild animals belonging to 17 orders from northern Nigeria was conducted. Faecal samples were collected from the wild animals in zoological gardens in four states and analysed using the flotation and simple sedimentation techniques. Overall, parasite eggs or cysts were detected in 47% (n=102) of the animals examined. High parasite prevalence, 80%, 75%, 71%, 60 % and 50% were recorded for members of the orders Testudines, Perissodactyla, Artiodactyla, Primates and Rodentia respectively. Multiple infections involving two or three parasite taxa were recorded in some of the captive wild animals examined with a significant association (p<0.05) between the animals and nematode eggs, Taenia eggs and Eimeria oocysts. Others helminth species such as Ascaris, Hookworm, Enterobius, Entamoeba, Trichuris and Strongyloides were also detected. This calls for caution as the wild animals may serve as source of infection to attendants and visitors to the zoosPeer reviewe