Culicoides segnis and Culicoides pictipennis Biting Midges (Diptera, Ceratopogonidae), New Reported Vectors of Haemoproteus Parasites

Abstract

As bloodsuckers of birds, Culicoides biting midges (Diptera, Ceratopogonidae) play an important role in the transmission of avian haemosporidian (Haemoproteus) parasites, which are prevalent in many bird populations and cause disease, pathology, or even mortality in their hosts. Information about the role of the various Culicoides species in the transmission of Haemoproteus parasites remains insufficient. This presents an obstacle for the better understanding of the epizootiology of haemoproteosis. The aim of this study was to determine new Culicoides species involved in the transmission of Haemoproteus parasites in the wild. Biting midges were collected using UV traps on the Curonian Spit, Lithuania. Only parous Culicoides females were investigated: they were identified and were diagnosed for the presence of Haemoproteus parasites using both microscopy and PCR-based methods. We collected and dissected 420 parous Culicoides females. PCR-based screening showed that 28 parous Culicoides biting midges were infected with avian Haemoproteus parasites. Haemoproteid DNA was detected in Culicoides kibunensis, Culicoides pictipennis, Culicoides festivipennis, Culicoides segnis, Culicoides pallidicornis, and Culicoides obsoletus biting midges. The DNA of Haemoproteus palloris, genetic lineage hWW1, was found for the first time in C. pallidicornis. Haemoproteus sporozoites were detected in the salivary glands of two Culicoides segnis biting midges. According to the PCR results, one female contained Haemoproteus tartakovskyi (genetic lineage hHAWF1) DNA and another Haemoproteus majoris (genetic lineage hCCF5) DNA. The sporozoites of Haemoproteus parasites were also detected in the salivary glands of four C. pictipennis biting midges using microscopy, and this finding was confirmed by PCR as Haemoproteus parabelopolskyi DNA (genetic lineage hSYAT02) was detected in three out of the four biting midges. The obtained results supplement existing information about Culicoides biting midges as natural vectors of Haemoproteus spp. and add two new Culicoides species to the vector list, showing the low specificity of these parasites for the invertebrate hosts.

Insights into the Biology of Leucocytozoon Species (Haemosporida, Leucocytozoidae): Why Is There Slow Research Progress on Agents of Leucocytozoonosis?

“…The total number of slides to examine should be few because of the predominantly low natural prevalence of Leucocytozoon infections in wild simuliids. This method was effective for determining vectors of Haemoproteus , as well as for studying the natural feeding preferences of biting midges and black flies [ 314 , 315 , 316 , 317 ].…”

What Can Haemosporidian Lineages Found in Culicoides Biting Midges Tell Us about Their Feeding Preferences?

“…They are transmitted by Culicoides biting midges; however, little is known about their natural vectors. There are almost 180 described species of Haemoproteus parasites [1], and more than 1400 species of Culicoides worldwide [2]; however, the natural vectors of Haemoproteus are known for only a small portion of parasite species [3][4][5][6]. Further, considering only studies combining the investigation of sporozoites in salivary gland preparations and using molecular tools to confirm parasite species and lineage, this number is even smaller [3][4][5][6].…”

“…Only 14 species of biting midges have been confirmed to be PCR-positive for Haemoproteus parasite DNA in Europe [3,[5][6][7][8][9][10][11][12], which merely indicates that they had fed on infected birds, but not that the insect is a competent vector for the parasite. For this confirmation, it is necessary to prove the presence of sporozoites (the infective stage of haemosporidian parasites) in the insect salivary glands [13], which, in natural infections, was done for only six species of Haemoproteus (H. pallidus cytochrome b lineage PFC1, H. parabelopolskyi SYAT02, H. majoris CCF5, H. tartakovskyi HAWF1, H. minutus TURDUS2, and H. asymmetricus TUPHI01) and three species of Culicoides (C. kibunensis, C. pictipennis, and C. segnis) [3,5,6].…”

“…If the Culicoides species does not naturally feed upon the infected vertebrate host, it will not acquire the parasite, or transmit it. For example, the majority of these experimental studies have been conducted with C. impunctatus and C. nubeculosus [4], but so far, these two biting midge species have not been proven to be natural vectors of Haemoproteus parasites [3,5,6], probably because they are mammalophilic biting midge species, feeding on birds only opportunistically [17][18][19].…”

First report of Culicoides caucoliberensis in Spain: Exploring molecular phylogeny, host‐feeding behaviour and avian haemosporidian parasites

“…No haemosporidian parasites ( Haemoproteus or Plasmodium parasites), were detected in the pools or blood‐fed females specimens analysed. The prevalence of pathogens in field‐collected Culicoides is usually low and varies among different species (Veiga et al, 2018; Žiegytė et al, 2022). Note that the low number of samples tested in our study could have contributed to the apparent absence of haemosporidians in the sampling site.…”