Ecological and epidemiological status of species of the Phlebotomus perniciosus complex (Diptera: Psychodidae, Phlebotominae) in Morocco

Abstract

Leishmania infantum (Kinetoplastida: Trypanosomatidae) infection is transmitted by an infected female sand fly (Diptera: Psychodidae, Phlebotominae) of the subgenus Larroussius: Phlebotomus ariasi, Phlebotomus perniciosus, and Phlebotomus longicuspis in the Mediterranean basin. In Morocco, the vectorial role of P. ariasi was demonstrated, while that of P. longicuspis and P. perniciosus is not elucidated. In addition, Moroccan P. longicuspis and P. perniciosus populations present a higher morphologic and genetic variability. It was classified as P. perniciosus complex, including typical (PN) and atypical (PNA) morphs of P. perniciosus, P. longicuspis sensu stricto (LCss), and a sibling species of P. longicuspis (LCx). With the aim to study the ecological and epidemiological status of P. perniciosus complex species in Morocco, entomological surveys were carried out during three entomological seasons (2012, 2013, and 2014). We collected a total of 6298 specimens from 81 localities of northern, central, and southern Morocco. After describing the geographical distribution of P. perniciosus complex trough Morocco according to many variables (altitude, latitude, and longitude), we discuss the resulting epidemiological implications of its species. Our results highlight the geographical distribution of the two morphs of P. perniciosus through Morocco: PN is limited to the north, while PNA is widespread in northern, central, and southern Morocco. In terms of vectorial role, we hypothesize the potential involvement of PN, LCss, and LCx, at least, with P. ariasi, in the epidemiological cycle of L. infantum in Morocco.

Urbanization of human visceral leishmaniasis in Morocco

“… Zarrouk et al (2015) hypothesized the potential involvement of typical (PN) and atypical (PNA) morphs of P. perniciosus , P. longicuspis sensu stricto (LCss), and P. longicuspis (LCx), at least, with P. ariasi , in the epidemiological cycle of L. infantum in Morocco.…”

Emerging and Re-Emerging Leishmaniases in the Mediterranean Area: What Can Be Learned from a Retrospective Review Analysis of the Situation in Morocco during 1990 to 2010?

“…In Morocco, ZVL was initially confined to the northern province of Taounate but has since spread to other territories [ 10 , 41 , 42 ]. P. ariasi , P. perniciosus and P. longicuspis are vectors of L. infantum [ 40 , 43 ].…”

“…Two main clinical forms can be distinguished: visceral (VL) and cutaneous (CL) [ 8 ]. In Morocco, zoonotic visceral leishmaniasis (ZVL) is caused by Leishmania infantum with dogs as the primary reservoir, and three Phlebotomus species— P. ariasi , P. perniciosus and P. longicuspis —as vectors [ 9 , 10 ]. Cutaneous leishmaniases are caused by Leishmania major , Leishmania tropica and L. infantum .…”

Potential distributions of phlebotomine sandfly vectors of human visceral leishmaniasis caused by Leishmania infantum in Morocco

“…Data on proven and potential vector occurrences were obtained from intensive sampling across Morocco. Thus, typical (PN) and atypical (PNA) forms of P. perniciosus (Pesson et al, 2004;Zarrouk et al, 2015), P. longicuspis, P. ariasi, Phlebotomus alexandri, P. langeroni and Sergentomyia minuta (Diptera: Psychodidae) were collected from 59 localities across northern and central Morocco, where L. infantum human VL has been recorded (MMH, 2017). Sandfly sampling was conducted using Centers for Disease Control (CDC) light traps for 10 trap-nights per year per site during the leishmaniasis transmission seasons between May 2010 and September 2018.…”