Browsing by Author "Bitam, Idir"

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Acquisition and excretion of bartonella quintana by the cat flea, ctenocephalides felis felis
(John Wiley & Sons, 2014) Kernif, Tahar; Leulmi, Hamza; Socolovschi, Cristina; Berenger, Jean-Michel; Lepidi, Hubert; Bitam, Idir; Rolain, Jean-Marc; Raoult, Didier; Parola, Philippe
Body lice of homeless people reveal the presence of several emerging bacterial pathogens in northern Algeria
(Joseph M. Vinetz, University of California San Diego School of Medicine, UNITED STATES, 2018) Louni, Meriem; Mana, Nassima; Bitam, Idir; Dahmani, Mustapha; Parola, Philippe; Fenollar, Florence; Raoult, Didier; Mediannikov, Oleg
Human lice, Pediculus humanus, are obligate blood-sucking parasites. Body lice, Pediculus h. humanus, occur in two divergent mitochondrial clades (A and D) each exhibiting a particular geographic distribution. Currently, the body louse is recognized as the only vector for louse-borne diseases. In this study, we aimed to study the genetic diversity of body lice collected from homeless populations in three localities of northern Algeria, and to investigate louse-borne pathogens in these lice
Competence of cimex lectularius bed bugs for the transmission of bartonella quintana, the agent of trench fever
(Public Library of Science, 2015) Leulmi, Hamza; Bitam, Idir; Berenger, Jean Michel; Lepidi, Hubert; Rolain, Jean Marc; Almeras, Lionel; Raoult, Didier; Parola, Philippe
Bartonella quintana, the etiologic agent of trench fever and other human diseases, is transmitted by the feces of body lice. Recently, this bacterium has been detected in other arthropod families such as bed bugs, which begs the question of their involvement in B. quintana transmission. Although several infectious pathogens have been reported and are suggested to be transmitted by bed bugs, the evidence regarding their competence as vectors is unclear. Bed bugs at the adult and instar developmental stages were fed three successive human blood meals inoculated with B. quintana bacterium from day one (D1) to D5; subsequently they were fed with pathogen-free human blood until the end of the experiment. Bed bugs and feces were collected in time series, to evaluate their capacities to acquire, multiply and expel viable B. quintana using molecular biology, immunohistochemistry and cultures assays. B. quintana was detected molecularly in 100% of randomly selected experimentally infected bed bug specimens (D3). The monitoring of B. quintana in bed bug feces showed that the bacterium was detectable starting on the 3rd day post-infection (pi) and persisted until day 18±1 pi. Although immunohistochemistry assays localized the bacteria to the gastrointestinal bed bug gut, the detection of B. quintana in the first and second instar larva stages suggested a vertical non-transovarial transmission of the bacterium. The present work demonstrated for the first time that bed bugs can acquire, maintain for more than 2 weeks and release viable B. quintana organisms following a stercorarial shedding. We also observed the vertical transmission of the bacterium to their progeny. Although the biological role of bed bugs in the transmission of B. quintana under natural conditions has yet to be confirmed, the present work highlights the need to reconsider monitoring of these arthropods for the transmission of human pathogens
Contribution to the Monitoring of Leptospira in Wild Animals (Hedgehog of Bouira District)
(2021) Aouadi, Nawal; Mensah Tonyi, Raouf; Abbas, Sadjia; Bitam, Idir; Arab, Karim
Leptospirosis is an anthropozoonotique disease of worldwide distribution with tropical dominance. It is caused by a pathogenic bacterium Leptospira interrogans which her primary reservoirs are rodents that shed the bacteria in the urine. Leptospira is wide- spread in the environment (freshwater, moist soil, sludge...). This study was carried out at Pasteur Institute of Algiers PIA’s laboratory, the ecology of vector systems department in different regions of Bouira district focused on the detection of leptospira spp in different samples: blood, organs, and urine of wild-caught animals (hedgehogs). After analysis of various samples (9 hedgehogs) in regions M'chedallah, Raffour, and Ahl- el –Ksar in 2012, we were able to iso- late leptospira by the bacteriological test (culture of urine, liver, and kidney) 22.22% of positivity, Test of thermo- resistant antigen (33.33% of positivity) and Microscopic-Agglutination-Test (0%). These diagnostic approaches appear to be complementary
Detection of bacterial pathogens in clade E head lice collected from Niger’s refugees in Algeria
(BMS, 2018) Louni, Meriem; Amanzougaghene, Nadia; Mana, Nassima; Fenollar, Florence; Raoult, Didier; Bitam, Idir
Background: Head lice, Pediculus humanus capitis, are obligate blood-sucking parasites. Phylogenetically, they occur in five divergent mitochondrial clades (A, D, B, C and E), each having a particular geographical distribution. Recent studies have revealed that head lice, as is the case of body lice, can act as a vector for louse-borne diseases. Here, we aimed to study the genetic diversity of head lice collected from Niger’s refugees (migrant population) arriving in Algeria, northern Africa, and to look for louse-borne pathogens. Comparative head lice samples collected from indigenous population of schoolchildren (non-immigrant) were also analyzed to frame the study. Results: In this study, 37 head lice samples were collected from 31 Nigerien refugees, as well as 45 head lice from 27 schoolchildren. The collection was established in three localities of eastern Algiers, north Algeria. Quantitative real-time PCR screening of pathogens bacteria and the genetic characterisation of the head lice satut were performed. Through amplification and sequencing of the cytb gene, results showed that all head lice of Nigerien refugees 37/82 (45.12%) belonged to clade E with the presence of four new haplotypes, while, of the 45 head lice of schoolchildren, 34/82 lice (41.46%) belonged to clade A and 11/82 (13.41%) belonged to clade B. Our study is the first to report the existence of clade E haplogroup in Nigerien head lice. DNA of Coxiella burnetii was detected in 3/37 (8.10%) of the head lice collected from 3 of the 31 (9.67%) migrant population. We also revealed the presence of Acinetobacter DNA in 20/37 (54.05%) of head lice collected from 25/31 (80.64%) of the Nigerien refugees, and in 25/45 (55.55%) head lice collected from 15/27 (55.55%) schoolchildren. All positive Nigerien-head lice for Acinetobacter spp. were identified as A. baumannii, while positive schoolchildren-head lice were identified as A. johnsonii 15/25 (60%), A. variabilis 8/25 (32%) and A. baumannii 2/25 (8%). Conclusions: Based on these findings from head lice collected on migrant and non-migrant population, our results show, for the first time, that head lice from Niger belong to haplogroup E, and confirm that the clade E had a west African distribution. We also detected, for the first time, the presence of C. burnetii and A. baumannii in these Nigerien head lice. Nevertheless, further studies are needed to determine whether the head lice can transmit these pathogenic bacteria from one person to another
Detection of rickettsia felis, rickettsia typhi, bartonella species and yersinia pestis in fleas (siphonaptera) from Africa
(Public Library of Science, 2014) Leulmi, Hamza; Socolovschi, Cristina; Laudisoit, Anne; Houemenou, Gualbert; Davoust, Bernard; Bitam, Idir; Raoult, Didier; Parola, Philippe
Little is known about the presence/absence and prevalence of Rickettsia spp, Bartonella spp. and Yersinia pestis in domestic and urban flea populations in tropical and subtropical African countries. Fleas collected in Benin, the United Republic of Tanzania and the Democratic Republic of the Congo were investigated for the presence and identity of Rickettsia spp., Bartonella spp. and Yersinia pestis using two qPCR systems or qPCR and standard PCR. In Xenopsylla cheopis fleas collected from Cotonou (Benin), Rickettsia typhi was detected in 1% (2/199), and an uncultured Bartonella sp. was detected in 34.7% (69/199). In the Lushoto district (United Republic of Tanzania), R. typhi DNA was detected in 10% (2/20) of Xenopsylla brasiliensis, and Rickettsia felis was detected in 65% (13/20) of Ctenocephalides felis strongylus, 71.4% (5/7) of Ctenocephalides canis and 25% (5/20) of Ctenophthalmus calceatus calceatus. In the Democratic Republic of the Congo, R. felis was detected in 56.5% (13/23) of Ct. f. felis from Kinshasa, in 26.3% (10/38) of Ct. f. felis and 9% (1/11) of Leptopsylla aethiopica aethiopica from Ituri district and in 19.2% (5/26) of Ct. f. strongylus and 4.7% (1/21) of Echidnophaga gallinacea. Bartonella sp. was also detected in 36.3% (4/11) of L. a. aethiopica. Finally, in Ituri, Y. pestis DNA was detected in 3.8% (1/26) of Ct. f. strongylus and 10% (3/30) of Pulex irritans from the villages of Wanyale and Zaa. Most flea-borne infections are neglected diseases which should be monitored systematically in domestic rural and urban human populations to assess their epidemiological and clinical relevance. Finally, the presence of Y. pestis DNA in fleas captured in households was unexpected and raises a series of questions regarding the role of free fleas in the transmission of plague in rural Africa, especially in remote areas where the flea density in houses is high
First account of arthropods in the nest of the white stork, ciconia ciconia, in Algeria, including the flea ctenocephalides felis
(Societe Zoologique de France, 2014) Mammeria, Aicha Beya; Bitam, Idir; Kernif, Tahar
Genomic insights into a new citrobacter koseri strain revealed gene exchanges with the Virulence-Associated yersinia pestis pPCP1 plasmid
(Frontiers Media, 2016) Armougom, Fabrice; Bitam, Idir; Croce, Olivier; Merhej, Vicky; Barassi, Lina; Ti-Thien, Nguyen; La Scola, Bernard; Raoult, Didier
The history of infectious diseases raised the plague as one of the most devastating for human beings. Far too often considered an ancient disease, the frequent resurgence of the plague has led to consider it as a reemerging disease in Madagascar, Algeria, Libya, and Congo. The genetic factors associated with the pathogenicity of Yersinia pestis, the causative agent of the plague, involve the acquisition of the pPCP1 plasmid that promotes host invasion through the expression of the virulence factor Pla. The surveillance of plague foci after the 2003 outbreak in Algeria resulted in a positive detection of the specific pla gene of Y. pestis in rodents. However, the phenotypic characterization of the isolate identified a Citrobacter koseri. The comparative genomics of our sequenced C. koseri URMITE genome revealed a mosaic gene structure resulting from the lifestyle of our isolate and provided evidence for gene exchanges with different enteric bacteria. The most striking was the acquisition of a continuous 2 kb genomic fragment containing the virulence factor Pla of the Y. pestis pPCP1 plasmid; however, the subcutaneous injection of the CKU strain in mice did not produce any pathogenic effect. Our findings demonstrate that fast molecular detection of plague using solely the pla gene is unsuitable and should rather require Y. pestis gene marker combinations. We also suggest that the evolutionary force that might govern the expression of pathogenicity can occur through the acquisition of virulence genes but could also require the loss or the inactivation of resident genes such as antivirulence genes
Human head lice and pubic lice reveal the presence of several Acinetobacter species in Algiers, Algeria
(Elsevier, 2017) Manaa, Nassima; Louni, Meriem; Parola, Philippe; Bitam, Idir
There are two majorspecies of medically important lice that parasitize humans: Phthirus pubis, found in pubic hair, and Pediculus humanus. Pediculus humanus consists of two eco types that live in specific niches on the human host: body lice (Pediculus humanus humanus), found on the human body and clothing, and head lice (Pediculus humanus capitis), found on the scalp. To date, only body lice are known to be vectors of human disease; however, it has recently been reported that the DNA of several bacterial agents has been detected in head lice, raising questions about their role in the transmission of pathogens. This issue caught our attention, in addition to the fact that the pathogenic bacteria associated with P. pubis and P. humanus capitis have never been investigated in Algeria. To investigate this,molecular techniques (real-time PCR) were used to screen for the presence of Acinetobacter spp., Bartonella spp., Borrelia spp. and Rickettsia prowazekii DNA from P. humanus capitis (64 lice) collected from schoolchildren,and P. pubis (4 lice),collected from one adultman living in Algiers. Positive samples for Acinetobacter spp.were identified by sequencing therpoBgene. Conventional PCR targeting the partial Cytb gene was used to determine the phylogenetic clade of the collected lice. Of the 64 samples collected, Acinetobacter spp. DNA was detected in 17/64 (27%) of head lice, identified as: A. baumannii (14%), A. johnsonii (11%) and A. variabilis (2%). Of the four P. pubissamples, 2(50%) were positive for A. johnsonii. The phylogenetic tree based on the Cytb gene revealed that P. humanus capitis were grouped into clades A and B. In this study, we report andidentify for the first time Acinetobacter spp.in Algerian P. pubis and P. humanus capitis. The detection of the genus Acinetobacter in lice should not be underestimated, especially in P. humanus capitis, which is distributed worldwide. However, additional epidemiological data are required to determine if human lice may act as an environmental reservoir and are actively involved in the propagation of these bacteria to humans
Immunodominant IgE epitopes of Der p 5 allergen
(Bentham Science Publishers, 2018) Lahiani, Sadjia; Dumez, Marie-Eve; Bouaziz, Ahlem; Djenouhat, Kamel; Khemili, Souad; Bitam, Idir; Gilis, Dimitri; Galleni, Moreno
Microorganisms associated with the North African hedgehog Atelerix algirus and its parasitizing arthropods in Algeria
(Elsevier, 2022) Aouadi, Nawal; Benkacimi, Linda; Zan Diarra, Adama; Laroche, MaureenLaroche; Bérenger, Jean-Michel; Bitam, Idir; Parola, Philippe
Hedgehogs are small mammals. They are potential reservoirs of various zoonotic agents. This study was conducted in Bouira, a north-central region of Algeria. A total of 21 Atelerix algirus corpses were picked up on roadsides and gardens. Hedgehog kidneys, spleens and ectoparasites were collected. Twelve hedgehogs were infested with ectoparasites, including Archaeopsylla erinacei, Rhipicephalus sanguineus s.l. and Haemaphysalis erinacei. Hedgehog organs and randomly selected arthropods were screened for microorganisms using molecular methods. Coxiella burnetii was detected in kidneys, spleens, A. erinacei, Hae. erinacei and Rh. sanguineus s.l. Leptospira interrogans was detected in kidneys. Rickettsia felis and Rickettsia massiliae were detected respectively in A. erinacei and in Rh. sanguineus s.l. DNA of an uncultivated Rickettsia spp. was found in Hae. erinacei. Wolbachia spp. DNA was detected in fleas. The DNA of potential new Bartonella and Ehrlichia species were found respectively in fleas and ticks. This study highlights the presence of DNA from a broad range of microorganisms in hedgehogs and their ectoparasites that may be responsible for zoonoses in Algeria
Molecular detection of Leishmania infantum DNA and host blood meal identification in Phlebotomus in a hypoendemic focus of human leishmaniasis in northern Algeria
(Gabriele SchoÈnian, ChariteÂ University Medicine Berlin, GERMANY, 2018) Bennai, Kahina; Tahir, Djamel; Lafri, Ismail; Bendjaballah-Laliam, Amina; Bitam, Idir; Parola, Philippe
Leishmania parasites are transmitted by female phlebotomine sand flies that maintain the enzootic cycle by circulating between sylvatic and domestic mammals. Humans are part of this cycle as accidental hosts due to the vector's search for a source of blood. In Algeria, Human Leishmaniases (HL) are endemic and represent a serious public health problem because of their high annual incidence and their spread across the country. The aim of this study is to identify sand fly species fauna (vectors of Leishmania), determine their infection rate and identify their feeding preferences using molecular tools in a hypoendemic focus of HL located in the province of Tipaza, northern Algeria.
Molecular Surveillance of Yersinia pestis from Stray Dogs and Cats and their Fleas in Algiers
(Razi Vaccine and Serum Research Institute, 2024) Zaidi, Sara; Bessas, Amina; Hezil, Djamila; Benseghir, H.; Bitam, Idir
In recent years, plague has re-emerged in several countries around the world and remains endemic in some regions. In a natural environment, and in contact with rodents and their fleas, stray carnivores are most at risk of catching the disease and maintaining the spread of the bacillus. The objective of this study is to demonstrate the presence or absence of Yersinia pestis in stray dogs and cats in the Algiers region by molecular methods and thus contribute their role in epidemiology of this disease. Molecular research of Yersinia pestis has also been conducted on fleas from these carnivores. Preliminary identification of ectoparasites to genus and species level was performed. Real-time polymerase chain reaction targeting Yersinia pestis pla gene was used to survey the plague agent in fleas and carnivores captured as stray animals in Algiers (Algeria). Positive qPCR results were tested by PCR sequencing using glpD gene. Among 327 fleas captured from 107 dogs and 365 fleas from 140 cats, prevalence of Ctenocephalides felis was higher in cats (86,96%), whereas that of Ctenocephalides canis and Xenopsylla cheopis was higher in dogs (90,57% and 92,63% respectively). While internal and external PCR positive controls were positive, none of the 107 dogs spleen and 140 cat spleens and none of the 256 analyzed fleas were positive for Y. pestis. These results suggest that stray cats and dogs are unlikely sources for plague in Algeria contrary to that has been reported in other plague-endemic countries. This observation illustrates that plague epidemiological chain varies from one region to another
Potential of Artesunate in the treatment of visceral leishmaniasis in dogs naturally infected by Leishmania infantum: Efficacy evidence from a randomized field trial
(2020) Medkour, Hacène; Bitam, Idir; Laidoudi, Younes; Lafri, Ismail; Lounas, Abdelaziz; Hamidat, Hamza Karim; Mekroud, Abdeslam; Varloud, Marie; Bernard, Davoust; Oleg, Mediannikov
Leishmaniasis is among the world’s most neglected diseases. Dogs are the main reservoirs/hosts of Leishmania infantum, causative agent of both canine and human visceral leishmaniosis. Canine leishmaniasis (CanL) represents a public health problem as one of the most prevalent zoonotic diseases worldwide. Current therapeutics present drawbacks; thus, there is a need for more effective, safer, and cheaper drugs. The aim of this study was to evaluate and to compare the efficacy of oral administration of artesunate or meglumine antimoniate/allopurinol in dogs with clinical leishmaniasis. Forty-two dogs with naturally occurring clinical leishmaniasis were included in this open-label, simple randomized positive-control clinical field trial with 6 months of follow-up. Dogs received meglumine antimoniate 100 mg/kg/day and allopurinol 30 mg/kg/day for 28 days (control group, n = 26) or artesunate 25 mg/kg/day for 6 days (test group, n = 16). The animals were evaluated for their clinical evolution, parasite load (by qPCR) and humoral response at different time points: 0, 30, 90, and 180 days after treatment. Data analyses showed a significant improvement in both groups in clinical scores, parasitemia and antibody titers after treatment. Compared to the control group, the artesunate group showed significantly lower clinical score (P = 0.0001), lower parasitemia (P = 0.0001) and antibody titers after 6 months of follow-up. Compared to baseline values, a rapid, significant reduction (P < 0.012) in antibody levels, 2.28- versus 3.04-fold for the control versus artesunate groups, respectively, was observed 30 days after treatment. Antibody levels continued to decrease further in the artesunate group, where 58% of cases became seronegative at the 6-month follow-up. All qPCR-positive dogs were negative after treatment with artesunate, while 14.3% remained positive with the appearance of two new cases in the control group. Artesunate was well tolerated, and no side effects were recorded. Treatment failures were similar in both groups with 27.27% (6/22), including 18.18% (4/22) mortality in the control group, versus 26.66% (4/15), including 13.33% (2/15) mortality in the artesunate group. This is the first report showing the potential of artesunate in the treatment of dogs with clinical leishmaniasis. Artesunate showed higher efficacy than the current first-line treatment for CanL without any adverse effects. It could be a good alternative chemotherapy for CanL, and may be considered for further studies in human leishmaniases. Further clinical trials are needed to confirm these findings, to determine if there are relapses after treatment and if dogs remain infective to sandflies, to define the ideal therapeutic dosage and duration of treatment with artesunate.
Update on tick-borne rickettsioses around the world : a geographic approach
(American Society for Microbiology, 2013) Parola, Philippe; Paddock, Christopher D.; Socolovschi, Cristina; Labruna, Marcelo B.; Mediannikov, Oleg; Kernif, Tahar; Abdad, Mohammad Yazid; Stenos, John; Bitam, Idir; Fournier, Pierre-Edouard; Raoult, Didier
Tick-borne rickettsioses are caused by obligate intracellular bacteria belonging to the spotted fever group of the genus Rickettsia. These zoonoses are among the oldest known vector-borne diseases. However, in the past 25 years, the scope and importance of the recognized tick-associated rickettsial pathogens have increased dramatically, making this complex of diseases an ideal paradigm for the understanding of emerging and reemerging infections. Several species of tick-borne rickettsiae that were considered nonpathogenic for decades are now associated with human infections, and novel Rickettsia species of undetermined pathogenicity continue to be detected in or isolated from ticks around the world. This remarkable expansion of information has been driven largely by the use of molecular techniques that have facilitated the identification of novel and previously recognized rickettsiae in ticks. New approaches, such as swabbing of eschars to obtain material to be tested by PCR, have emerged in recent years and have played a role in describing emerging tick-borne rickettsioses. Here, we present the current knowledge on tick-borne rickettsiae and rickettsioses using a geographic approach toward the epidemiology of these diseases
The white stork Ciconia ciconia in the northeast of Algeria, and its relation with climatic change between 1996 and 2014
(Elsevier, 2017) Mammeria, Aicha Beya; Triplet, Patrick; Bitam, Idir