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Chikeka I, Dumler JS. Neglected bacterial zoonoses. Clin Microbiol Infect 2015; 21:404-15. [PMID: 25964152 DOI: 10.1016/j.cmi.2015.04.022] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 04/24/2015] [Accepted: 04/25/2015] [Indexed: 01/07/2023]
Abstract
Bacterial zoonoses comprise a group of diseases in humans or animals acquired by direct contact with or by oral consumption of contaminated animal materials, or via arthropod vectors. Among neglected infections, bacterial zoonoses are among the most neglected given emerging data on incidence and prevalence as causes of acute febrile illness, even in areas where recognized neglected tropical diseases occur frequently. Although many other bacterial infections could also be considered in this neglected category, five distinct infections stand out because they are globally distributed, are acute febrile diseases, have high rates of morbidity and case fatality, and are reported as commonly as malaria, typhoid or dengue virus infections in carefully designed studies in which broad-spectrum diagnoses are actively sought. This review will focus attention on leptospirosis, relapsing fever borreliosis and rickettsioses, including scrub typhus, murine typhus and spotted fever group rickettsiosis. Of greatest interest is the lack of distinguishing clinical features among these infections when in humans, which confounds diagnosis where laboratory confirmation is lacking, and in regions where clinical diagnosis is often attributed to one of several perceived more common threats. As diseases such as malaria come under improved control, the real impact of these common and under-recognized infections will become evident, as will the requirement for the strategies and allocation of resources for their control.
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Affiliation(s)
- I Chikeka
- Departments of Pathology and Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - J S Dumler
- Departments of Pathology and Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA.
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Wagemakers A, Staarink PJ, Sprong H, Hovius JWR. Borrelia miyamotoi: a widespread tick-borne relapsing fever spirochete. Trends Parasitol 2015; 31:260-9. [PMID: 25892254 DOI: 10.1016/j.pt.2015.03.008] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 02/20/2015] [Accepted: 03/20/2015] [Indexed: 11/28/2022]
Abstract
Borrelia miyamotoi is a relapsing fever spirochete that has only recently been identified as a human pathogen. Borrelia miyamotoi is genetically and ecologically distinct from Borrelia burgdorferi sensu lato, while both are present in Ixodes ticks. Over 50 patients with an acute febrile illness have been described with a B. miyamotoi infection, and two infected immunocompromised patients developed a meningoencephalitis. Seroprevalence studies indicate exposure in the general population and in specific risk groups, such as patients initially suspected of having human granulocytic anaplasmosis. Here, we review the available literature on B. miyamotoi, describing its presence in ticks, reservoir hosts, and humans, and discussing its potential impact on public health.
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Affiliation(s)
- Alex Wagemakers
- Center for Experimental and Molecular Medicine, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Pieter J Staarink
- Center for Experimental and Molecular Medicine, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands
| | - Hein Sprong
- Laboratory for Zoonoses and Environmental Microbiology, National Institute for Public Health and Environment (RIVM), Antonie van Leeuwenhoeklaan 9, PO Box 1, Bilthoven, The Netherlands
| | - Joppe W R Hovius
- Center for Experimental and Molecular Medicine, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands; Department of Internal Medicine, Division of Infectious Diseases, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands; Amsterdam Multidisciplinary Lyme Center, Academic Medical Center, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands.
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Souidi Y, Boudebouch N, Ezikouri S, Belghyti D, Trape JF, Sarih M. Borrelia crocidurae in Ornithodoros ticks from northwestern Morocco: a range extension in relation to climatic change? JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2014; 39:316-320. [PMID: 25424260 DOI: 10.1111/jvec.12106] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 06/16/2014] [Indexed: 06/04/2023]
Abstract
Tick-borne relapsing fever (TBRF) is caused by Borrelia spirochetes transmitted to humans by Argasid soft ticks of the genus Ornithodoros. We investigated the presence of Ornithodoros ticks in rodent burrows in nine sites of the Gharb region of northwestern Morocco where we recently documented a high incidence of TBRF in humans. We assessed the Borrelia infection rate by nested PCR and sequencing. All sites investigated were colonized by ticks of the Ornithodoros marocanus complex and a high proportion of burrows (38.4%) were found to be infested. Borrelia infections were observed in 6.8% of the ticks tested. Two Borrelia species were identified by sequencing: B. hispanica and B. crocidurae. The discovery in northwestern Morocco of Ornithodoros ticks infected by B. crocidurae represents a 350 km range extension of this Sahelo-Saharan spirochete in North Africa. The spread of B. crocidurae may be related to the increasing aridity of northwestern Morocco in relation to climate change.
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Affiliation(s)
- Yassine Souidi
- Institut Pasteur du Maroc, Laboratoire des Maladies Vectorielles, 1 Place Louis Pasteur, 20360 Casablanca, Morocco; Faculté des Sciences, Université Ibn Tofail, Kénitra, Morocco
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Maladjusted host immune responses induce experimental cerebral malaria-like pathology in a murine Borrelia and Plasmodium co-infection model. PLoS One 2014; 9:e103295. [PMID: 25075973 PMCID: PMC4116174 DOI: 10.1371/journal.pone.0103295] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 06/27/2014] [Indexed: 01/26/2023] Open
Abstract
In the Plasmodium infected host, a balance between pro- and anti-inflammatory responses is required to clear the parasites without inducing major host pathology. Clinical reports suggest that bacterial infection in conjunction with malaria aggravates disease and raises both mortality and morbidity in these patients. In this study, we investigated the immune responses in BALB/c mice, co-infected with Plasmodium berghei NK65 parasites and the relapsing fever bacterium Borrelia duttonii. In contrast to single infections, we identified in the co-infected mice a reduction of L-Arginine levels in the serum. It indicated diminished bioavailability of NO, which argued for a dysfunctional endothelium. Consistent with this, we observed increased sequestration of CD8+ cells in the brain as well over expression of ICAM-1 and VCAM by brain endothelial cells. Co-infected mice further showed an increased inflammatory response through IL-1β and TNF-α, as well as inability to down regulate the same through IL-10. In addition we found loss of synchronicity of pro- and anti-inflammatory signals seen in dendritic cells and macrophages, as well as increased numbers of regulatory T-cells. Our study shows that a situation mimicking experimental cerebral malaria (ECM) is induced in co-infected mice due to loss of timing and control over regulatory mechanisms in antigen presenting cells.
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Fotso Fotso A, Mediannikov O, Diatta G, Almeras L, Flaudrops C, Parola P, Drancourt M. MALDI-TOF mass spectrometry detection of pathogens in vectors: the Borrelia crocidurae/Ornithodoros sonrai paradigm. PLoS Negl Trop Dis 2014; 8:e2984. [PMID: 25058611 PMCID: PMC4109908 DOI: 10.1371/journal.pntd.0002984] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 05/14/2014] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In Africa, relapsing fever borreliae are neglected vector-borne pathogens that cause mild to deadly septicemia and miscarriage. Screening vectors for the presence of borreliae currently requires technically demanding, time- and resource-consuming molecular methods. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has recently emerged as a tool for the rapid identification of vectors and the identification of cultured borreliae. We investigated whether MALDI-TOF-MS could detect relapsing fever borreliae directly in ticks. METHODOLOGY/PRINCIPAL FINDINGS As a first step, a Borrelia MALDI-TOF-MS database was created to house the newly determined Mean Spectrum Projections for four Lyme disease group and ten relapsing fever group reference borreliae. MALDI-TOF-MS yielded a unique protein profile for each of the 14 tested Borrelia species, with 100% reproducibility over 12 repeats. In a second proof-of-concept step, the Borrelia database and a custom software program that subtracts the uninfected O. sonrai profile were used to detect Borrelia crocidurae in 20 Ornithodoros sonrai ticks, including eight ticks that tested positive for B. crocidurae by PCR-sequencing. A B. crocidurae-specific pattern consisting of 3405, 5071, 5898, 7041, 8580 and 9757-m/z peaks was found in all B. crocidurae-infected ticks and not found in any of the un-infected ticks. In a final blind validation step, MALDI-TOF-MS exhibited 88.9% sensitivity and 93.75% specificity for the detection of B. crocidurae in 50 O. sonrai ticks, including 18 that tested positive for B. crocidurae by PCR-sequencing. MALDI-TOF-MS took 45 minutes to be completed. CONCLUSIONS/SIGNIFICANCE After the development of an appropriate database, MALDI-TOF-MS can be used to identify tick species and the presence of relapsing fever borreliae in a single assay. This work paves the way for the use of MALDI-TOF-MS for the dual identification of vectors and vectorized pathogens.
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Affiliation(s)
- Aurélien Fotso Fotso
- URMITE, UMR 6236, CNRS 7278, IRD 198, INSERM 1095, Méditerranée Infection, Faculté de Médecine, Aix-Marseille Université, Marseille, France
| | - Oleg Mediannikov
- URMITE, UMR 6236, CNRS 7278, IRD 198, INSERM 1095, Méditerranée Infection, Faculté de Médecine, Aix-Marseille Université, Marseille, France; URMITE, UMR, IRD 198, Campus IRD Ham Manisty, Dakar, Senegal
| | - Georges Diatta
- URMITE, UMR, IRD 198, Campus IRD Ham Manisty, Dakar, Senegal
| | - Lionel Almeras
- URMITE, UMR 6236, CNRS 7278, IRD 198, INSERM 1095, Méditerranée Infection, Faculté de Médecine, Aix-Marseille Université, Marseille, France
| | - Christophe Flaudrops
- Pôle de Maladies Infectieuses, Assistance Publique-Hôpitaux de Marseille, CHU Timone, Marseille, France
| | - Philippe Parola
- URMITE, UMR 6236, CNRS 7278, IRD 198, INSERM 1095, Méditerranée Infection, Faculté de Médecine, Aix-Marseille Université, Marseille, France
| | - Michel Drancourt
- URMITE, UMR 6236, CNRS 7278, IRD 198, INSERM 1095, Méditerranée Infection, Faculté de Médecine, Aix-Marseille Université, Marseille, France
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Lopez JE, Vinet-Oliphant H, Wilder HK, Brooks CP, Grasperge BJ, Morgan TW, Stuckey KJ, Embers ME. Real-time monitoring of disease progression in rhesus macaques infected with Borrelia turicatae by tick bite. J Infect Dis 2014; 210:1639-48. [PMID: 24879799 DOI: 10.1093/infdis/jiu306] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The hallmark of disease caused by tick- and louse-borne relapsing fever due to Borrelia infection is cyclic febrile episodes, which in humans results in severe malaise and may lead to death. To evaluate the pathogenesis of relapsing fever due to spirochetes in an animal model closely related to humans, disease caused by Borrelia turicatae after tick bite was compared in 2 rhesus macaques in which radiotelemetry devices that recorded body temperatures in 24-hour increments were implanted. The radiotelemetry devices enabled real-time acquisition of core body temperatures and changes in heart rates and electrocardiogram intervals for 28 consecutive days without the need to constantly manipulate the animals. Blood specimens were also collected from all animals for 14 days after tick bite, and spirochete densities were assessed by quantitative polymerase chain reaction. The complexity of disease caused by relapsing-fever spirochetes was demonstrated in the nonhuman primates monitored in real time. The animals experienced prolonged episodes of hyperthermia and hypothermia; disruptions in their diurnal patterns and repolarization of the heart were also observed. This is the first report of the characterizing disease progression with continuous monitoring in an animal model of relapsing fever due to Borrelia infection.
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Affiliation(s)
| | | | | | | | - Britton J Grasperge
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, Louisiana
| | - Timothy W Morgan
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Starkville
| | | | - Monica E Embers
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, Louisiana
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The Borrelia hermsii factor H binding protein FhbA is not required for infectivity in mice or for resistance to human complement in vitro. Infect Immun 2014; 82:3324-32. [PMID: 24866803 DOI: 10.1128/iai.01892-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The primary causative agent of tick-borne relapsing fever in North America is Borrelia hermsii. It has been hypothesized that B. hermsii evades complement-mediated destruction by binding factor H (FH), a host-derived negative regulator of complement. In vitro, B. hermsii produces a single FH binding protein designated FhbA (FH binding protein A). The properties and ligand binding activity of FhbA suggest that it plays multiple roles in pathogenesis. It binds plasminogen and has been identified as a significant target of a B1b B cell-mediated IgM response in mice. FhbA has also been explored as a potential diagnostic antigen for B. hermsii infection in humans. The ability to test the hypothesis that FhbA is a critical virulence factor in vivo has been hampered by the lack of well-developed systems for the genetic manipulation of the relapsing fever spirochetes. In this report, we have successfully generated a B. hermsii fhbA deletion mutant (the B. hermsii YORΔfhbA strain) through allelic exchange mutagenesis. Deletion of fhbA abolished FH binding by the YORΔfhbA strain and eliminated cleavage of C3b on the cell surface. However, the YORΔfhbA strain remained infectious in mice and retained resistance to killing in vitro by human complement. Collectively, these results indicate that B. hermsii employs an FhbA/FH-independent mechanism of complement evasion that allows for resistance to killing by human complement and persistence in mice.
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Elbir H, Abi-Rached L, Pontarotti P, Yoosuf N, Drancourt M. African relapsing Fever borreliae genomospecies revealed by comparative genomics. Front Public Health 2014; 2:43. [PMID: 25229054 PMCID: PMC4157404 DOI: 10.3389/fpubh.2014.00043] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 04/29/2014] [Indexed: 11/15/2022] Open
Abstract
Background: Relapsing fever borreliae are vector-borne bacteria responsible for febrile infection in humans in North America, Africa, Asia, and in the Iberian Peninsula in Europe. Relapsing fever borreliae are phylogenetically closely related, yet they differ in pathogenicity and vectors. Their long-term taxonomy, based on geography and vector grouping, needs to be re-apprised in a genomic context. We therefore embarked into genomic analyses of relapsing fever borreliae, focusing on species found in Africa. Results: Genome-wide phylogenetic analyses group Old World Borrelia crocidurae, Borrelia hispanica, B. duttonii, and B. recurrentis in one clade, and New World Borrelia turicatae and Borrelia hermsii in a second clade. Accordingly, average nucleotide identity is 99% among B. duttonii, B. recurrentis, and B. crocidurae and 96% between latter borreliae and B. hispanica while the similarity is 86% between Old World and New World borreliae. Comparative genomics indicates that the Old World relapsing fever B. duttonii, B. recurrentis, B. crocidurae, and B. hispanica have a 2,514-gene pan genome and a 933-gene core genome that includes 788 chromosomal and 145 plasmidic genes. Analyzing the role that natural selection has played in the evolution of Old World borreliae species revealed that 55 loci were under positive diversifying selection, including loci coding for membrane, flagellar, and chemotaxis proteins, three categories associated with adaption to specific niches. Conclusion: Genomic analyses led to a reappraisal of the taxonomy of relapsing fever borreliae in Africa. These analyses suggest that B. crocidurae, B. duttonii, and B. recurrentis are ecotypes of a unique genomospecies, while B. hispanica is a distinct species.
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Affiliation(s)
- Haitham Elbir
- URMITE, UMR63, CNRS 7278, IRD 198, INSERM 1095, Aix Marseille Université , Marseille , France
| | - Laurent Abi-Rached
- Equipe ATIP, Centre National de la Recherche Scientifique, Laboratoire d'Analyse, Topologie, Probabilités - Unité Mixte de Recherche 7353, Aix Marseille Université , Marseille , France
| | - Pierre Pontarotti
- Equipe EBM, Centre National de la Recherche Scientifique, Laboratoire d'Analyse, Topologie, Probabilités - Unité Mixte de Recherche 7353, Aix-Marseille Université , Marseille , France
| | - Niyaz Yoosuf
- URMITE, UMR63, CNRS 7278, IRD 198, INSERM 1095, Aix Marseille Université , Marseille , France
| | - Michel Drancourt
- URMITE, UMR63, CNRS 7278, IRD 198, INSERM 1095, Aix Marseille Université , Marseille , France
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Impact of drought on vector-borne diseases – how does one manage the risk? Public Health 2014; 128:29-37. [DOI: 10.1016/j.puhe.2013.09.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 09/05/2013] [Accepted: 09/16/2013] [Indexed: 11/22/2022]
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Mediannikov O, Diatta G, Kasongo K, Raoult D. Identification of Bartonellae in the soft tick species Ornithodoros sonrai in Senegal. Vector Borne Zoonotic Dis 2013; 14:26-32. [PMID: 24359424 DOI: 10.1089/vbz.2013.1326] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ticks, belonging to the soft ticks species Ornithodorus sonrai, have been collected from six sites in Senegal and were tested for the presence of Bartonella spp. Initial screening by PCR revealed the presence of these bacteria in ticks from two villages, Soulkhou Thissé (5/8, 62.5%) and Maka Gouye (1/24, 4.2%). Three bacterial strains were isolated from live ticks, and the genetic characterization of these strains suggests that they belong to two previously unknown species. The pathogenicity of these two new species of Bartonella is not yet known. The new isolates described here are the first strains of Bartonella spp. from soft ticks and the first isolates from any arthropod species in Africa.
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Affiliation(s)
- Oleg Mediannikov
- 1 URMITE (Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes) IRD 198, CNRS 7278, Université de la Méditerranée , Faculté de Médecine, Marseille, France and campus commun UCAD-IRD of Hann, BP 1386 CP 18524 Dakar, Senegal
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Abstract
The study of relapsing fever borreliae in Africa has long suffered from the use of non-specific laboratory tools for the direct detection of these spirochetes in clinical and vector specimens. Accordingly, Borrelia hispanica, Borrelia crocidurae, Borrelia duttonii, and Borrelia recurrentis have traditionally been distinguished on the basis of geography and vector and the unproven hypothesis that each species was exclusive to one vector. The recent sequencing of three relapsing fever Borrelia genomes in our laboratory prompted the development of more specific tools and a reappraisal of the epidemiology in Africa. Five additional potential species still need to be cultured from clinical and vector sources in East Africa to further assess their uniqueness. Here, we review the molecular evidence of relapsing fever borreliae in hosts and ectoparasites in Africa and explore the diversity, geographical distribution, and vector association of these pathogens for Africans and travelers to Africa.
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Affiliation(s)
- Haitham Elbir
- Aix Marseille Université, URMITE, UMR63 CNRS 7278, IRD 198, Inserm 1095, Marseille, France.
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Trape JF, Diatta G, Arnathau C, Bitam I, Sarih M, Belghyti D, Bouattour A, Elguero E, Vial L, Mané Y, Baldé C, Pugnolle F, Chauvancy G, Mahé G, Granjon L, Duplantier JM, Durand P, Renaud F. The epidemiology and geographic distribution of relapsing fever borreliosis in West and North Africa, with a review of the Ornithodoros erraticus complex (Acari: Ixodida). PLoS One 2013; 8:e78473. [PMID: 24223812 PMCID: PMC3817255 DOI: 10.1371/journal.pone.0078473] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 09/06/2013] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Relapsing fever is the most frequent bacterial disease in Africa. Four main vector / pathogen complexes are classically recognized, with the louse Pediculus humanus acting as vector for B. recurrentis and the soft ticks Ornithodoros sonrai, O. erraticus and O. moubata acting as vectors for Borrelia crocidurae, B. hispanica and B. duttonii, respectively. Our aim was to investigate the epidemiology of the disease in West, North and Central Africa. METHODS AND FINDINGS From 2002 to 2012, we conducted field surveys in 17 African countries and in Spain. We investigated the occurrence of Ornithodoros ticks in rodent burrows in 282 study sites. We collected 1,629 small mammals that may act as reservoir for Borrelia infections. Using molecular methods we studied genetic diversity among Ornithodoros ticks and Borrelia infections in ticks and small mammals. Of 9,870 burrows investigated, 1,196 (12.1%) were inhabited by Ornithodoros ticks. In West Africa, the southern and eastern limits of the vectors and Borrelia infections in ticks and small mammals were 13°N and 01°E, respectively. Molecular studies revealed the occurrence of nine different Ornithodoros species, including five species new for science, with six of them harboring Borrelia infections. Only B. crocidurae was found in West Africa and three Borrelia species were identified in North Africa: B. crocidurae, B. hispanica, and B. merionesi. CONCLUSIONS Borrelia Spirochetes responsible for relapsing fever in humans are highly prevalent both in Ornithodoros ticks and small mammals in North and West Africa but Ornithodoros ticks seem absent south of 13°N and small mammals are not infected in these regions. The number of Ornithodoros species acting as vector of relapsing fever is much higher than previously known.
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Affiliation(s)
- Jean-François Trape
- Institut de recherche pour le développement, Laboratoire de Paludologie Et Zoologie Médicale, Dakar, Senegal
| | - Georges Diatta
- Institut de recherche pour le développement, Laboratoire de Paludologie Et Zoologie Médicale, Dakar, Senegal
| | - Céline Arnathau
- Institut de Recherche pour le Développement, UMR (CNRS IRD) MIVEGEC, Montpellier, France
| | - Idir Bitam
- Institut Pasteur d’Algérie, Laboratoire d’Écologie des Systèmes Vectoriels, Algiers, Algeria
| | - M’hammed Sarih
- Institut Pasteur du Maroc, Laboratoire des Maladies Vectorielles, Casablanca, Morocco
| | - Driss Belghyti
- Université Ibn Tofail, Département de Biologie, Faculté des Sciences, Kénitra, Morocco
| | - Ali Bouattour
- Institut Pasteur de Tunis, Service d’Entomologie Médicale, Tunis, Tunisia
| | - Eric Elguero
- Institut de Recherche pour le Développement, UMR (CNRS IRD) MIVEGEC, Montpellier, France
| | - Laurence Vial
- Institut de recherche pour le développement, Laboratoire de Paludologie Et Zoologie Médicale, Dakar, Senegal
- Institut de Recherche pour le Développement, UMR (CNRS IRD) MIVEGEC, Montpellier, France
| | - Youssouph Mané
- Institut de recherche pour le développement, Laboratoire de Paludologie Et Zoologie Médicale, Dakar, Senegal
| | - Cellou Baldé
- Institut Pasteur de Guinée, Laboratoire d’Entomologie Médicale et de Vénimologie, Kindia, Guinea
| | - Franck Pugnolle
- Institut de Recherche pour le Développement, UMR (CNRS IRD) MIVEGEC, Montpellier, France
| | - Gilles Chauvancy
- Institut de recherche pour le développement, Laboratoire de Paludologie Et Zoologie Médicale, Dakar, Senegal
| | - Gil Mahé
- Institut de Recherche pour le Développement, UMR Hydrosciences, Montpellier, France
| | - Laurent Granjon
- Institut de Recherche pour le Développement, Centre de Biologie et de Gestion des Populations, Dakar, Senegal
| | - Jean-Marc Duplantier
- Institut de Recherche pour le Développement, Centre de Biologie et de Gestion des Populations, Dakar, Senegal
| | - Patrick Durand
- Institut de Recherche pour le Développement, UMR (CNRS IRD) MIVEGEC, Montpellier, France
| | - François Renaud
- Institut de Recherche pour le Développement, UMR (CNRS IRD) MIVEGEC, Montpellier, France
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Rustenhoven-Spaan I, Melkert P, Nelissen E, van Roosmalen J, Stekelenburg J. Maternal mortality in a rural Tanzanian hospital: fatal Jarisch-Herxheimer reaction in a case of relapsing fever in pregnancy. Trop Doct 2013; 43:138-41. [PMID: 23976777 DOI: 10.1177/0049475513497477] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Relapsing fever is a disease caused by one of the species of Borrelia. It is often misdiagnosed as malaria and can have fatal complications such as the Jarisch-Herxheimer reaction (JHR) after the commencement of treatment with antibiotics. A 19-year-old Tanzanian woman was admitted after a term home delivery that day. She presented with a 2 day history of fever, headache, general body malaise and vomiting. She was misdiagnosed as having severe malaria and was treated with quinine. The blood slide showed Borrelia duttoni. The patient continued treatment with procaine penicillin fortified for relapsing fever. Several hours later the woman died, probably due to JHR. This case of a patient with relapsing fever who died from a JHR stresses the importance of adequate diagnosis and treatment which should include careful monitoring, especially for the first hours after starting antibiotics.
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Moemenbellah-Fard MD, Benafshi O, Rafinejad J, Ashraf H. Tick-borne relapsing fever in a new highland endemic focus of western Iran. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2013; 103:529-37. [DOI: 10.1179/136485909x451852] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Goutier S, Ferquel E, Pinel C, Bosseray A, Hoen B, Couetdic G, Bourahoui A, Lapostolle C, Pelloux H, Garnier M, Sertour N, Pelloux I, Pavese P, Cornet M. Borrelia crocidurae meningoencephalitis, West Africa. Emerg Infect Dis 2013; 19:301-4. [PMID: 23347436 PMCID: PMC3559064 DOI: 10.3201/eid1902.121325] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Borrelia crocidurae–associated relapsing fever is endemic to West Africa and is considered benign. We report 4 patients with B. crocidurae–associated neurologic symptoms; 2 of their cases had been misdiagnosed. Frequency and severity of this disease could be underestimated; molecular methods and serodiagnostic tests for Lyme disease might be helpful in its detection.
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Stanke C, Kerac M, Prudhomme C, Medlock J, Murray V. Health effects of drought: a systematic review of the evidence. PLOS CURRENTS 2013; 5:ecurrents.dis.7a2cee9e980f91ad7697b570bcc4b004. [PMID: 23787891 PMCID: PMC3682759 DOI: 10.1371/currents.dis.7a2cee9e980f91ad7697b570bcc4b004] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Introduction. Climate change projections indicate that droughts will become more intense in the 21 century in some areas of the world. The El Niño Southern Oscillation is associated with drought in some countries, and forecasts can provide advance warning of the increased risk of adverse climate conditions. The most recent available data from EMDAT estimates that over 50 million people globally were affected by drought in 2011. Documentation of the health effects of drought is difficult, given the complexity in assigning a beginning/end and because effects tend to accumulate over time. Most health impacts are indirect because of its link to other mediating circumstances like loss of livelihoods. Methods. The following databases were searched: MEDLINE; CINAHL; Embase; PsychINFO, Cochrane Collection. Key references from extracted papers were hand-searched, and advice from experts was sought for further sources of literature. Inclusion criteria for papers summarised in tables include: explicit link made between drought as exposure and human health outcomes; all study designs/methods; all countries/contexts; any year of publication. Exclusion criteria include: drought meaning shortage unrelated to climate; papers not published in English; studies on dry/arid climates unless drought was noted as an abnormal climatological event. No formal quality evaluation was used on papers meeting inclusion criteria. Results. 87 papers meeting the inclusion criteria are summarised in tables. Additionally, 59 papers not strictly meeting the inclusion criteria are used as supporting text in relevant parts of the results section. Main categories of findings include: nutrition-related effects (including general malnutrition and mortality, micronutrient malnutrition, and anti-nutrient consumption); water-related disease (including E coli, cholera and algal bloom); airborne and dust-related disease (including silo gas exposure and coccidioidomycosis); vector borne disease (including malaria, dengue and West Nile Virus); mental health effects (including distress and other emotional consequences); and other health effects (including wildfire, effects of migration, and damage to infrastructure). Conclusions. The probability of drought-related health impacts varies widely and largely depends upon drought severity, baseline population vulnerability, existing health and sanitation infrastructure, and available resources with which to mitigate impacts as they occur. The socio-economic environment in which drought occurs influences the resilience of the affected population. Forecasting can be used to provide advance warning of the increased risk of adverse climate conditions and can support the disaster risk reduction process. Despite the complexities involved in documentation, research should continue and results should be shared widely in an effort to strengthen drought preparedness and response activities.
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Affiliation(s)
- Carla Stanke
- Extreme Events and Health Protection Section, Health Protection Agency, London, UK
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Chappuis F, Alirol E, d’Acremont V, Bottieau E, Yansouni C. Rapid diagnostic tests for non-malarial febrile illness in the tropics. Clin Microbiol Infect 2013; 19:422-31. [DOI: 10.1111/1469-0691.12154] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 12/21/2012] [Accepted: 01/07/2013] [Indexed: 11/30/2022]
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Ratmanov P, Mediannikov O, Raoult D. Vectorborne diseases in West Africa: geographic distribution and geospatial characteristics. Trans R Soc Trop Med Hyg 2013; 107:273-84. [PMID: 23479360 DOI: 10.1093/trstmh/trt020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
This paper provides an overview of the methods in which geographic information systems (GIS) and remote sensing (RS) technology have been used to visualise and analyse data related to vectorborne diseases (VBD) in West Africa and to discuss the potential for these approaches to be routinely included in future studies of VBDs. GIS/RS studies of diseases that are associated with a specific geographic landscape were reviewed, including malaria, human African trypanosomiasis, leishmaniasis, lymphatic filariasis, Loa loa filariasis, onchocerciasis, Rift Valley fever, dengue, yellow fever, borreliosis, rickettsioses, Buruli ulcer and Q fever. RS data and powerful spatial modelling methods improve our understanding of how environmental factors affect the vectors and transmission of VBDs. There is great potential for the use of GIS/RS technologies in the surveillance, prevention and control of vectorborne and other infectious diseases in West Africa.
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Affiliation(s)
- Pavel Ratmanov
- Aix Marseille Université, URMITE, UMR CNRS 7278, IRD 198, INSERM 1095, 27 Boulevard Jean Moulin, 13385 Marseille cedex 05, France
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Elbir H, Henry M, Diatta G, Mediannikov O, Sokhna C, Tall A, Socolovschi C, Cutler SJ, Bilcha KD, Ali J, Campelo D, Barker SC, Raoult D, Drancourt M. Multiplex real-time PCR diagnostic of relapsing fevers in Africa. PLoS Negl Trop Dis 2013; 7:e2042. [PMID: 23390560 PMCID: PMC3561136 DOI: 10.1371/journal.pntd.0002042] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 12/15/2012] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND In Africa, relapsing fever borreliae are neglected arthropod-borne pathogens causing mild to deadly septicemia and miscarriage. The closely related Borrelia crocidurae, Borrelia duttonii, Borrelia recurrentis and Borrelia hispanica are rarely diagnosed at the species level, hampering refined epidemiological and clinical knowledge of the relapsing fevers. It would be hugely beneficial to have simultaneous detection and identification of Borrelia to species level directly from clinical samples. METHODOLOGY/PRINCIPAL FINDINGS We designed a multiplex real-time PCR protocol targeting the 16S rRNA gene detecting all four Borrelia, the glpQ gene specifically detecting B. crocidurae, the recN gene specifically detecting B. duttonii/B. recurrentis and the recC gene specifically detecting B. hispanica. Compared to combined 16S rRNA gene and flaB gene sequencing as the gold standard, multiplex real-time PCR analyses of 171 Borrelia-positive and 101 Borrelia-negative control blood specimens yielded 100% sensitivity and specificity for B. duttonii/B. recurrentis and B. hispanica and 99% sensitivity and specificity for B. crocidurae. CONCLUSIONS/SIGNIFICANCE The multiplex real-time PCR developed in this study is a rapid technique for both molecular detection and speciation of relapsing fever borreliae from blood in Africa. It could be incorporated in point-of-care laboratory to confirm diagnosis and provide evidence of the burden of infection attributed to different species of known or potentially novel relapsing fever borreliae.
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Affiliation(s)
- Haitham Elbir
- Aix Marseille Université, URMITE, UMR63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
| | - Mireille Henry
- Aix Marseille Université, URMITE, UMR63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
| | | | - Oleg Mediannikov
- Aix Marseille Université, URMITE, UMR63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
- URMITE, UMR IRD 198 CNRS 7278, Dakar, Senegal
| | | | | | - Cristina Socolovschi
- Aix Marseille Université, URMITE, UMR63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
| | - Sally J. Cutler
- School of Health, Sports and Bioscience, University of East London, London, United Kingdom
| | - Kassahum D. Bilcha
- College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Jemal Ali
- College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Dayana Campelo
- Parasitology Section, School of Chemistry and Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Steven C. Barker
- Parasitology Section, School of Chemistry and Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Didier Raoult
- Aix Marseille Université, URMITE, UMR63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
| | - Michel Drancourt
- Aix Marseille Université, URMITE, UMR63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
- * E-mail:
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Point-of-care laboratory of pathogen diagnosis in rural Senegal. PLoS Negl Trop Dis 2013; 7:e1999. [PMID: 23350001 PMCID: PMC3547848 DOI: 10.1371/journal.pntd.0001999] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 11/21/2012] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND In tropical Africa, where the spectrum of the bacterial pathogens that cause fevers is poorly understood and molecular-based diagnostic laboratories are rare, the time lag between test results and patient care is a critical point for treatment of disease. METHODOLOGY/PRINCIPAL FINDINGS We implemented POC laboratory in rural Senegal to resolve the time lag between test results and patient care. During the first year of the study (February 2011 to January 2012), 440 blood specimens from febrile patients were collected in Dielmo and Ndiop villages. All samples were screened for malaria, dengue fever, Borrelia spp., Coxiella burnetii, Tropheryma whipplei, Rickettsia conorii, R. africae, R. felis, and Bartonella spp. CONCLUSIONS/SIGNIFICANCE We identified DNA from at least one pathogenic bacterium in 80/440 (18.2%) of the samples from febrile patients. B. crocidurae was identified in 35 cases (9.5%), and R. felis DNA was found in 30 cases (6.8%). The DNA of Bartonella spp. was identified in 23/440 cases (4.3%), and DNA of C. burnetii was identified in 2 cases (0.5%). T. whipplei (0.2%) was diagnosed in one patient. No DNA of R. africae or R. conorii was identified. Among the 7 patients co-infected by two different bacteria, we found R. felis and B. crocidurae in 4 cases, B. crocidurae and Bartonella spp. in 2 cases, and B. crocidurae and C. burnetii in 1 case. Malaria was diagnosed in 54 cases. In total, at least one pathogen (bacterium or protozoa) was identified in 127/440 (28.9%) of studied samples. Here, the authors report the proof of concept of POC in rural tropical Africa. Discovering that 18.2% of acute infections can be successfully treated with doxycycline should change the treatment strategy for acute fevers in West Africa.
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Schwan TG, Anderson JM, Lopez JE, Fischer RJ, Raffel SJ, McCoy BN, Safronetz D, Sogoba N, Maïga O, Traoré SF. Endemic foci of the tick-borne relapsing fever spirochete Borrelia crocidurae in Mali, West Africa, and the potential for human infection. PLoS Negl Trop Dis 2012; 6:e1924. [PMID: 23209863 PMCID: PMC3510061 DOI: 10.1371/journal.pntd.0001924] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 10/12/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Tick-borne relapsing fever spirochetes are maintained in endemic foci that involve a diversity of small mammals and argasid ticks in the genus Ornithodoros. Most epidemiological studies of tick-borne relapsing fever in West Africa caused by Borrelia crocidurae have been conducted in Senegal. The risk for humans to acquire relapsing fever in Mali is uncertain, as only a few human cases have been identified. Given the high incidence of malaria in Mali, and the potential to confuse the clinical diagnosis of these two diseases, we initiated studies to determine if there were endemic foci of relapsing fever spirochetes that could pose a risk for human infection. METHODOLOGY/PRINCIPAL FINDINGS We investigated 20 villages across southern Mali for the presence of relapsing fever spirochetes. Small mammals were captured, thin blood smears were examined microscopically for spirochetes, and serum samples were tested for antibodies to relapsing fever spirochetes. Ornithodoros sonrai ticks were collected and examined for spirochetal infection. In total, 11.0% of the 663 rodents and 14.3% of the 63 shrews tested were seropositive and 2.2% of the animals had active spirochete infections when captured. In the Bandiagara region, the prevalence of infection was higher with 35% of the animals seropositive and 10% infected. Here also Ornithodoros sonrai were abundant and 17.3% of 278 individual ticks tested were infected with Borrelia crocidurae. Fifteen isolates of B. crocidurae were established and characterized by multi-locus sequence typing. CONCLUSIONS/SIGNIFICANCE The potential for human tick-borne relapsing fever exists in many areas of southern Mali.
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Affiliation(s)
- Tom G. Schwan
- Laboratory of Zoonotic Pathogens, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, United States of America
- * E-mail:
| | - Jennifer M. Anderson
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Twinbrook, Maryland, United States of America
| | - Job E. Lopez
- Laboratory of Zoonotic Pathogens, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, United States of America
| | - Robert J. Fischer
- Laboratory of Zoonotic Pathogens, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, United States of America
| | - Sandra J. Raffel
- Laboratory of Zoonotic Pathogens, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, United States of America
| | - Brandi N. McCoy
- Laboratory of Zoonotic Pathogens, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, United States of America
| | - David Safronetz
- Laboratory of Virology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, United States of America
| | - Nafomon Sogoba
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Ousmane Maïga
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Sékou F. Traoré
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
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Jori F, Vial L, Penrith ML, Pérez-Sánchez R, Etter E, Albina E, Michaud V, Roger F. Review of the sylvatic cycle of African swine fever in sub-Saharan Africa and the Indian ocean. Virus Res 2012; 173:212-27. [PMID: 23142551 DOI: 10.1016/j.virusres.2012.10.005] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 10/05/2012] [Accepted: 10/06/2012] [Indexed: 11/17/2022]
Abstract
African swine fever (ASF) is a major limiting factor for pig production in most of the countries in Sub-Saharan Africa and the Indian Ocean. In the absence of vaccine, a good understanding of the ecology and epidemiology of the disease is fundamental to implement effective control measures. In selected countries of Southern and East Africa, the association between Ornithodoros moubata ticks and warthogs has been described in detail in the literature. However, for many other countries in the region, information related to the sylvatic cycle is lacking or incomplete. In West African countries, for instance, the role of wild pigs in the epidemiology of ASF has never been demonstrated and the existence and potential impact of a sylvatic cycle involving an association between soft ticks and warthogs is questionable. In other countries, other wild pig species such as the bushpigs (Potamochoerus spp.) can also be asymptomatically infected by the virus but their role in the epidemiology of the disease is unclear and might differ according to geographic regions. In addition, the methods and techniques required to study the role of wild hosts in ASF virus (ASFV) epidemiology and ecology are very specific and differ from the more traditional methods to study domestic pigs or other tick species. The aim of this review is (i) to provide a descriptive list of the methodologies implemented to study the role of wild hosts in African swine fever, (ii) to compile the available knowledge about the sylvatic cycle of ASFV in different regions of Sub-Saharan Africa and the Indian Ocean in addition to the one that has been described for East and Southern Africa, and (iii) to discuss current methodologies and available knowledge in order to identify new orientations for further field and experimental surveys.
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Affiliation(s)
- F Jori
- Cirad, AGIRs Research Unit, Campus International de Baillarguet, 34398 Montpellier, France.
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Penrith ML, Vosloo W, Jori F, Bastos ADS. African swine fever virus eradication in Africa. Virus Res 2012; 173:228-46. [PMID: 23142552 DOI: 10.1016/j.virusres.2012.10.011] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 10/07/2012] [Accepted: 10/08/2012] [Indexed: 12/15/2022]
Abstract
African swine fever was reported in domestic pigs in 26 African countries during the period 2009-2011. The virus exists in an ancient sylvatic cycle between warthogs (Phacochoerus africanus) and argasid ticks of the Ornithodoros moubata complex in many of the countries reporting outbreaks and in two further countries in the region. Eradication of the virus from the countries in eastern and southern Africa where the classic sylvatic cycle occurs is clearly not an option. However, the virus has become endemic in domestic pigs in 20 countries and the great majority of outbreaks in recent decades, even in some countries where the sylvatic cycle occurs, have been associated with movement of infected pigs and pig meat. Pig production and marketing and ASF control in Africa have been examined in order to identify risk factors for the maintenance and spread of ASF. These include large pig populations, traditional free-range husbandry systems, lack of biosecurity in semi-intensive and intensive husbandry systems, lack of organisation in both pig production and pig marketing that results in lack of incentives for investment in pig farming, and ineffective management of ASF. Most of these factors are linked to poverty, yet pigs are recognised as a livestock species that can be used to improve livelihoods and contribute significantly to food security. The changes needed and how they might be implemented in order to reduce the risk of ASF to pig producers in Africa and to the rest of the world are explored.
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Affiliation(s)
- Mary-Louise Penrith
- Department of Veterinary Tropical Diseases, 0110 University of Pretoria, South Africa.
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Changing malaria epidemiology and diagnostic criteria for Plasmodium falciparum clinical malaria. PLoS One 2012; 7:e46188. [PMID: 23029433 PMCID: PMC3460864 DOI: 10.1371/journal.pone.0046188] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 08/30/2012] [Indexed: 11/21/2022] Open
Abstract
Background In tropical Africa, where malaria is highly endemic, low grade infections are asymptomatic and the diagnosis of clinical malaria is usually based on parasite density. Here we investigate how changes in malaria control and endemicity modify diagnostic criteria of Plasmodium falciparum attacks. Methods and Findings Parasitological and clinical data from the population of Dielmo, Senegal, monitored during 20 years, are analyzed in a random-effect logistic regression model to investigate the relationship between the level of parasitemia and risk of fever. Between 1990 and 2010, P. falciparum prevalence in asymptomatic persons declined from 85% to 1% in children 0–3 years and from 34% to 2% in adults ≥50 years. Thresholds levels of parasitemia for attributing fever episodes to malaria decreased by steps in relation to control policies. Using baseline threshold during following periods underestimated P. falciparum attacks by 9.8–20.2% in children and 18.9–40.2% in adults. Considering all fever episodes associated with malaria parasites as clinical attacks overestimated P. falciparum attacks by 42.2–68.5% in children and 45.9–211.7% in adults. Conclusions Malaria control modifies in all age-groups the threshold levels of parasitemia to be used for the assessment of malaria morbidity and to guide therapeutic decisions. Even under declining levels of malaria endemicity, the parasite density method must remain the reference method for distinguishing malaria from other causes of fever and assessing trends in the burden of malaria.
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Abstract
We announce the draft genome sequence of Borrelia crocidurae (strain Achema). The 1,557,560-bp genome (27% GC content) comprises one 919,477-bp linear chromosome and 638,083-bp plasmids that together carry 1,472 open reading frames, 32 tRNAs, and three complete rRNAs, with almost complete colinearity between B. crocidurae and Borrelia duttonii chromosomes.
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Diatta G, Souidi Y, Granjon L, Arnathau C, Durand P, Chauvancy G, Mané Y, Sarih M, Belghyti D, Renaud F, Trape JF. Epidemiology of tick-borne borreliosis in Morocco. PLoS Negl Trop Dis 2012; 6:e1810. [PMID: 23029574 PMCID: PMC3441398 DOI: 10.1371/journal.pntd.0001810] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 07/25/2012] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The presence in Morocco of Argasid ticks of the Ornithodoros erraticus complex, the vector of tick-borne relapsing fever (TBRF) in North Africa, has been known since 1919, but the disease is rarely diagnosed and few epidemiological data are available. METHODOLOGY/PRINCIPAL FINDINGS Between 2006 and 2011, we investigated the presence of Ornithodoros ticks in rodent burrows in 34 sites distributed across Morocco. We also collected small mammals in 10 sites and we investigated TBRF in febrile patients in Kenitra district. The prevalence of Borrelia infections was assessed by nested PCR amplification in ticks and the brain tissue of small mammals, and by evaluation of thick blood films in patients. A high proportion of burrows were infested with ticks of the O. erraticus complex in all regions of Morocco, with a mean of 39.5% for the whole country. Borrelia infections were found in 39/382 (10.2%) of the ticks and 12/140 (8.6%) of the rodents and insectivores studied by PCR amplification, and 102 patients tested positive by thick blood film. Five small mammalian species were found infected: Dipodillus campestris, Meriones shawi, Gerbillus hoogstrali, Gerbillus occiduus and Atelerix algirus. Three Borrelia species were identified in ticks and/or rodents: B. hispanica, B. crocidurae and B. merionesi. CONCLUSIONS/SIGNIFICANCE Tick populations belonging to O. erraticus complex are widely distributed in Morocco and a high proportion of ticks and small mammals are infected by Borrelia species. Although rarely diagnosed, TBRF may be a common cause of morbidity in all regions of Morocco.
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Affiliation(s)
- Georges Diatta
- Institut de Recherche pour le Développement, Laboratoire de Paludologie et de Zoologie Médicale, UMR 198, BP 1386, Dakar, Senegal
| | - Yassine Souidi
- Faculté des Sciences de Kénitra, Université Ibn Tofail, Kénitra, Morocco
- Institut Pasteur du Maroc, Casablanca, Morocco
| | - Laurent Granjon
- Institut de Recherche pour le Développement, Centre de Biologie et de Gestion des Populations, UMR 22, BP 1386, Dakar, Senegal
| | - Céline Arnathau
- Institut de Recherche pour le Développement, UMR 5290 MIVEGEC IRD/CNRS/UM, BP 64501, Montpellier, France
| | - Patrick Durand
- Institut de Recherche pour le Développement, UMR 5290 MIVEGEC IRD/CNRS/UM, BP 64501, Montpellier, France
| | - Gilles Chauvancy
- Institut de Recherche pour le Développement, Laboratoire de Paludologie et de Zoologie Médicale, UMR 198, BP 1386, Dakar, Senegal
| | - Youssouph Mané
- Institut de Recherche pour le Développement, Laboratoire de Paludologie et de Zoologie Médicale, UMR 198, BP 1386, Dakar, Senegal
| | | | - Driss Belghyti
- Faculté des Sciences de Kénitra, Université Ibn Tofail, Kénitra, Morocco
| | - François Renaud
- Institut de Recherche pour le Développement, Centre de Biologie et de Gestion des Populations, UMR 22, BP 1386, Dakar, Senegal
| | - Jean-François Trape
- Institut de Recherche pour le Développement, Laboratoire de Paludologie et de Zoologie Médicale, UMR 198, BP 1386, Dakar, Senegal
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Bottieau E, Verbruggen E, Aubry C, Socolovschi C, Vlieghe E. Meningoencephalitis complicating relapsing fever in traveler returning from Senegal. Emerg Infect Dis 2012; 18:697-8. [PMID: 22469185 PMCID: PMC3309691 DOI: 10.3201/eid1804.111771] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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Socolovschi C, Honnorat E, Consigny PH, Dougados J, Passeron A, Parola P, Raoult D. Tick-borne relapsing fever with cutaneous eschar and radiculopathy, Ethiopia. J Travel Med 2012; 19:261-3. [PMID: 22776391 DOI: 10.1111/j.1708-8305.2012.00625.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report the first confirmed case of tick-borne borreliosis by molecular tools in a French traveler returning from Ethiopia with unusual presentation: the presence of cutaneous eschar after a hard tick-bite suggesting firstly to clinicians a diagnosis of tick-borne rickettsiosis.
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Affiliation(s)
- Cristina Socolovschi
- Unité de recherche en maladies infectieuses et tropicales emergentes UMR 6236, CNRS-IRD 198, Faculté de Médecine, Aix-Marseille Université, Marseille, France
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Phylogenetic analysis of the spirochete Borrelia microti, a potential agent of relapsing fever in Iran. J Clin Microbiol 2012; 50:2873-6. [PMID: 22718931 DOI: 10.1128/jcm.00801-12] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report a role for Borrelia microti as a cause of relapsing fever in Iran supported by robust epidemiological evidence. The molecular identity of this spirochete and its relation with other relapsing fever borreliae have, until now, been poorly delineated. We analyzed an isolate of B. microti, obtained from Ornithodoros erraticus ticks, by sequencing four loci (16S rRNA, flaB, glpQ, intragenic spacer [IGS]) and comparing these sequences with those of other relapsing fever borreliae. Phylogenetic analysis using concatenated sequences of 16S rRNA, flaB, and glpQ grouped B. microti alongside three members of the African group, B. duttonii, B. recurrentis, and B. crocidurae, which are distinct from B. persica, the most prevalent established cause of tick-borne relapsing fever in Iran. The similarity values for 10 concatenated sequences totaling 2,437 nucleotides ranged from 92.11% to 99.84%, with the highest homologies being between B. duttonii and B. microti and between B. duttonii and B. recurrentis. Furthermore, the more discriminatory IGS sequence analysis corroborated the close similarity (97.76% to 99.56%) between B. microti and B. duttonii. These findings raise the possibility that both species may indeed be the same and further dispel the one-species, one-vector theory that has been the basis for classification of relapsing fever Borrelia for the last 100 years.
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Haitham E, Gimenez G, Sokhna C, Bilcha KD, Ali J, Barker SC, Cutler SJ, Raoult D, Drancourt M. Multispacer sequence typing relapsing fever Borreliae in Africa. PLoS Negl Trop Dis 2012; 6:e1652. [PMID: 22679518 PMCID: PMC3367985 DOI: 10.1371/journal.pntd.0001652] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 04/09/2012] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND In Africa, relapsing fevers are neglected arthropod-borne infections caused by closely related Borrelia species. They cause mild to deadly undifferentiated fever particularly severe in pregnant women. Lack of a tool to genotype these Borrelia organisms limits knowledge regarding their reservoirs and their epidemiology. METHODOLOGY/PRINCIPAL FINDINGS Genome sequence analysis of Borrelia crocidurae, Borrelia duttonii and Borrelia recurrentis yielded 5 intergenic spacers scattered between 10 chromosomal genes that were incorporated into a multispacer sequence typing (MST) approach. Sequencing these spacers directly from human blood specimens previously found to be infected by B. recurrentis (30 specimens), B. duttonii (17 specimens) and B. crocidurae (13 specimens) resolved these 60 strains and the 3 type strains into 13 species-specific spacer types in the presence of negative controls. B. crocidurae comprised of 8 spacer types, B. duttonii of 3 spacer types and B. recurrentis of 2 spacer types. CONCLUSIONS/SIGNIFICANCE Phylogenetic analyses of MST data suggested that B. duttonii, B. crocidurae and B. recurrentis are variants of a unique ancestral Borrelia species. MST proved to be a suitable approach for identifying and genotyping relapsing fever borreliae in Africa. It could be applied to both vectors and clinical specimens.
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Affiliation(s)
- Elbir Haitham
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), UMR CNRS 6236 IRD 198, Faculté de Médecine, Méditerranée Infection, Aix-Marseille Université, Marseille, France
| | - Gregory Gimenez
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), UMR CNRS 6236 IRD 198, Faculté de Médecine, Méditerranée Infection, Aix-Marseille Université, Marseille, France
| | - Cheikh Sokhna
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), UMR CNRS 6236 IRD 198, Méditerranée Infection, Aix-Marseille Université, Dakar, Senegal
| | | | - Jemal Ali
- College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Stephen C. Barker
- Parasitology Section, School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Sally J. Cutler
- School of Health, Sports and Bioscience, University of East London, London, United Kingdom
| | - Didier Raoult
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), UMR CNRS 6236 IRD 198, Faculté de Médecine, Méditerranée Infection, Aix-Marseille Université, Marseille, France
| | - Michel Drancourt
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), UMR CNRS 6236 IRD 198, Faculté de Médecine, Méditerranée Infection, Aix-Marseille Université, Marseille, France
- * E-mail:
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Yansouni CP, Bottieau E, Chappuis F, Phoba MF, Lunguya O, Ifeka BB, Jacobs J. Rapid diagnostic tests for a coordinated approach to fever syndromes in low-resource settings. Clin Infect Dis 2012; 55:610-1; author reply 611-2. [PMID: 22563019 DOI: 10.1093/cid/cis466] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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Nieto NC, Teglas MB, Stewart KM, Wasley T, Wolff PL. Detection of Relapsing Fever Spirochetes (Borrelia hermsiiandBorrelia coriaceae) in Free-Ranging Mule Deer (Odocoileus hemionus) from Nevada, United States. Vector Borne Zoonotic Dis 2012; 12:99-105. [DOI: 10.1089/vbz.2011.0716] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Nathan C. Nieto
- Department of Animal Biotechnology, University of Nevada, Reno, Nevada
| | - Mike B. Teglas
- Department of Animal Biotechnology, University of Nevada, Reno, Nevada
| | - Kelley M. Stewart
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada
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Keita AK, Bassene H, Tall A, Sokhna C, Ratmanov P, Trape JF, Raoult D, Fenollar F. Tropheryma whipplei: a common bacterium in rural Senegal. PLoS Negl Trop Dis 2011; 5:e1403. [PMID: 22206023 PMCID: PMC3243712 DOI: 10.1371/journal.pntd.0001403] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 09/29/2011] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Tropheryma whipplei is known as the cause of Whipple's disease, but it is also an emerging pathogen, detected in stool, that causes various chronic localized infections without histological digestive involvement and is associated with acute infections, including gastroenteritis and bacteremia. METHODS/PRINCIPAL FINDINGS We conducted a study in 2008 and 2009 using 497 non-diarrheic and diarrheic stool samples, 370 saliva samples, 454 sera samples and 105 samples obtained from water samples in two rural Sine-Saloum villages (Dielmo and Ndiop) in Senegal. The presence of T. whipplei was investigated by using specific quantitative PCR. Genotyping was performed on positive samples. A serological analysis by western blotting was performed to determine the seroprevalence and to detect seroconversion. Overall, T. whipplei was identified in 31.2% of the stool samples (139/446) and 3.5% of the saliva samples (13/370) obtained from healthy subjects. The carriage in the stool specimens was significantly (p<10(-3)) higher in children who were between 0 and 4 years old (60/80, 75%) compared to samples obtained from individuals who were between 5 to 10 years old (36/119, 30.2%) or between 11 and 99 years old (43/247, 17.4%). The carriage in the stool was also significantly more common (p = 0.015) in subjects with diarrhea (25/51, 49%). We identified 22 genotypes, 16 of which were new. Only one genotype (#53) was common to both villages. Among the specific genotypes, one (#52) was epidemic in Dielmo (15/28, 53.4%, p<10(-3)) and another (#49) in Ndiop (27.6%, p = 0.002). The overall seroprevalence was estimated at 72.8% (291/400). Seroconversion was detected in 66.7% (18/27) of children for whom PCR became positive in stools between 2008 and 2009. CONCLUSIONS/SIGNIFICANCE T. whipplei is a common bacterium in the Sine-Saloum area of rural Senegal that is contracted early in childhood. Epidemic genotypes suggest a human transmission of the bacterium.
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Affiliation(s)
- Alpha Kabinet Keita
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Université de la Méditerranée, Faculté de Médecine, Marseille, France
| | - Hubert Bassene
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Institut de Recherche pour le Développement (IRD), Campus commun UCAD-IRD of Hann, BP 1386, CP 18524, Dakar, Senegal
| | - Adama Tall
- Unité d'Epidémiologie, BP 220, Institut Pasteur de Dakar, Dakar, Senegal
| | - Cheikh Sokhna
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Institut de Recherche pour le Développement (IRD), Campus commun UCAD-IRD of Hann, BP 1386, CP 18524, Dakar, Senegal
| | - Pavel Ratmanov
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Université de la Méditerranée, Faculté de Médecine, Marseille, France
- Department of Public Health and Health Services Management, Far Eastern State Medical University, Khabarovsk, Russia
| | - Jean-François Trape
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Institut de Recherche pour le Développement (IRD), Campus commun UCAD-IRD of Hann, BP 1386, CP 18524, Dakar, Senegal
| | - Didier Raoult
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Université de la Méditerranée, Faculté de Médecine, Marseille, France
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Institut de Recherche pour le Développement (IRD), Campus commun UCAD-IRD of Hann, BP 1386, CP 18524, Dakar, Senegal
| | - Florence Fenollar
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Université de la Méditerranée, Faculté de Médecine, Marseille, France
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, URMITE CNRS-IRD 198 UMR 6236, Institut de Recherche pour le Développement (IRD), Campus commun UCAD-IRD of Hann, BP 1386, CP 18524, Dakar, Senegal
- * E-mail:
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Cotransmission of divergent relapsing fever spirochetes by artificially infected Ornithodoros hermsi. Appl Environ Microbiol 2011; 77:8494-9. [PMID: 21965393 DOI: 10.1128/aem.05830-11] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The soft tick Ornithodoros hermsi, which ranges in specific arboreal zones of western North America, acts as a vector for the relapsing fever spirochete Borrelia hermsii. Two genomic groups (genomic group I [GGI] and GGII) of B. hermsii are differentiated by multilocus sequence typing yet are codistributed in much of the vector's range. To test whether the tick vector can be infected via immersion, noninfected, colony-derived O. hermsi larvae were exposed to reduced-humidity conditions before immersion in culture suspensions of several GGI and GGII isolates. We tested for spirochetes in ticks by immunofluorescence microscopy and in mouse blood by quantitative PCR of the vtp locus to differentiate spirochete genotypes. The immersed larval ticks were capable of spirochete transmission to mice at the first nymphal feeding. Tick infection with mixed cultures of isolates DAH (vtp-6) (GGI) and MTW-2 (vtp-5) (GGII) resulted in ticks that caused spirochetemias in mice consisting of MTW-2 or both DAH and MTW-2. These findings show that this soft tick species can acquire B. hermsii by immersion in spirochete suspensions, that GGI and GGII isolates can coinfect the tick vector by this method, and that these spirochetes can be cotransmitted to a rodent host.
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85
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Multiplex 5' nuclease-quantitative PCR for diagnosis of relapsing fever in a large Tanzanian cohort. J Clin Microbiol 2011; 49:3245-9. [PMID: 21775542 DOI: 10.1128/jcm.00940-11] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Relapsing fever (RF) is caused by tick- and louse-borne Borrelia spp., is characterized by recurrent fever, and is often misdiagnosed as malaria. Because of submicroscopic bacteremia, microscopy can be insensitive between febrile bouts. We designed a multiplex quantitative PCR (qPCR) assay to distinguish RF Borrelia from Plasmodium falciparum and P. vivax. The assay specifically (100%) amplified pathogenic RF Borrelia (1 copy/reaction). We then tested blood from participants within a Tanzanian cohort assessed at scheduled intervals and with fever. Among 8,617 blood samples from 2,057 participants surveyed routinely, 7 (0.08%) samples and 7 (0.3%) participants had RF DNA (median, 4.4 × 10(3) copies/ml). Of 382 samples from 310 febrile persons, 15 (3.9%) samples from 13 (4.2%) participants had RF DNA (median, 7.9 × 10(2) copies/ml). Five (1.3%) samples from 4 (1.3%) participants were found to harbor Borrelia by microscopy. We conclude that multiplex qPCR holds promise for improved clinical diagnosis and epidemiologic assessment of RF.
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Genetic transformation of the relapsing fever spirochete Borrelia hermsii: stable integration and expression of green fluorescent protein from linear plasmid 200. J Bacteriol 2011; 193:3241-5. [PMID: 21551306 DOI: 10.1128/jb.05037-11] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tick-borne relapsing fever (TBRF) is a spirochetal disease caused by at least 15 different Borrelia species. It is a serious human health concern in regions of endemicity throughout the world. Transmission to humans occurs through the bites of infected Ornithodoros ticks. In North America, the primary Borrelia species associated with human disease are B. hermsii and B. turicatae. Direct demonstration of the role of putative TBRF spirochete virulence factors in the disease process has been hindered by the lack of a genetic manipulation system and complete genome sequences. Expanding on recent developments in these areas, here we demonstrate the successful generation of a clone of B. hermsii YOR that constitutively produces green fluorescent protein (GFP) (B. hermsii YOR::kan gfp). This strain was generated through introduction of a kan-gfp cassette into a noncoding region of the 200-kb B. hermsii linear plasmid lp200. Genetic manipulation did not affect the growth rate or trigger the loss of native plasmids. B. hermsii YOR::kan gfp retained infectivity and elicited host seroconversion. Stable production of GFP was demonstrated both in vitro and in vivo. This study represents a significant step forward in the development of tools that can be employed to study the virulence mechanisms of TBRF spirochetes.
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Parola P, Diatta G, Socolovschi C, Mediannikov O, Tall A, Bassene H, Trape JF, Raoult D. Tick-borne relapsing fever borreliosis, rural senegal. Emerg Infect Dis 2011; 17:883-5. [PMID: 21529402 PMCID: PMC3321757 DOI: 10.3201/eid1705.100573] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Detecting spirochetes remains challenging in cases of African tick-borne relapsing fever. Using real-time PCR specific for the 16S rRNA Borrelia gene, we found 27 (13%) of 206 samples from febrile patients in rural Senegal to be positive, whereas thick blood smear examinations conducted at dispensaries identified only 4 (2%) as positive.
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88
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Socolovschi C, Mediannikov O, Sokhna C, Tall A, Diatta G, Bassene H, Trape JF, Raoult D. Rickettsia felis-associated uneruptive fever, Senegal. Emerg Infect Dis 2010; 16:1140-2. [PMID: 20587190 PMCID: PMC3321914 DOI: 10.3201/eid1607.100070] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
During November 2008–July 2009, we investigated the origin of unknown fever in Senegalese patients with a negative malaria test result, focusing on potential rickettsial infection. Using molecular tools, we found evidence for Rickettsia felis–associated illness in the initial days of infection in febrile Senegalese patients without malaria.
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Affiliation(s)
- Cristina Socolovschi
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, 13385 Marseille, France
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Mediannikov O, Diatta G, Fenollar F, Sokhna C, Trape JF, Raoult D. Tick-borne rickettsioses, neglected emerging diseases in rural Senegal. PLoS Negl Trop Dis 2010; 4:e821. [PMID: 20856858 PMCID: PMC2939048 DOI: 10.1371/journal.pntd.0000821] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Accepted: 08/12/2010] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Rickettsioses are one of the most important causes of systemic febrile illness among travelers from developed countries, but little is known about their incidence in indigenous populations, especially in West Africa. METHODOLOGY/PRINCIPAL FINDINGS Overall seroprevalence evaluated by immunofluorescence using six rickettsial antigens (spotted fever and typhus group) in rural populations of two villages of the Sine-Saloum region of Senegal was found to be 21.4% and 51% for spotted fever group rickettsiae for Dielmo and Ndiop villages, respectively. We investigated the role of tick-borne rickettsiae as the cause of acute non-malarial febrile diseases in the same villages. The incidence of rickettsial DNA in 204 blood samples from 134 (62M and 72F) febrile patients negative for malaria was studied. DNA extracted from whole blood was tested by two qPCR systems. Rickettsial DNA was found in nine patients, eight with Rickettsia felis (separately reported). For the first time in West Africa, Rickettsia conorii was diagnosed in one patient. We also tested 2,767 Ixodid ticks collected in two regions of Senegal (Niakhar and Sine-Saloum) from domestic animals (cows, sheep, goats, donkeys and horses) by qPCR and identified five different pathogenic rickettsiae. We found the following: Rickettsia aeschlimannii in Hyalomma marginatum rufipes (51.3% and 44.8% in Niakhar and Sine-Saloum region, respectively), in Hyalomma truncatum (6% and 6.8%) and in Rhipicephalus evertsi evertsi (0.5%, only in Niakhar); R. c. conorii in Rh. e. evertsi (0.4%, only in Sine-Saloum); Rickettsia massiliae in Rhipicephalus guilhoni (22.4%, only in Niakhar); Rickettsia sibirica mongolitimonae in Hyalomma truncatum (13.5%, only in Sine-Saloum); and Rickettsia africae in Rhipicephalus evertsi evertsi (0.7% and 0.4% in Niakhar and Sine-Saloum region, respectively) as well as in Rhipicephalus annulatus (20%, only in Sine-Saloum). We isolated two rickettsial strains from H. truncatum: R. s. mongolitimonae and R. aeschlimannii. CONCLUSIONS/SIGNIFICANCE We believe that together with our previous data on the high prevalence of R. africae in Amblyomma ticks and R. felis infection in patients, the presented results on the distribution of pathogenic rickettsiae in ticks and the first R. conorii case in West Africa show that the rural population of Senegal is at risk for other tick-borne rickettsioses, which are significant causes of febrile disease in this area.
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Affiliation(s)
- Oleg Mediannikov
- URMITE, UMR IRD 198/CNRS 6236, Medical Faculty, Mediterranean University, Marseille, France and Dakar, Senegal
| | - Georges Diatta
- URMITE, UMR IRD 198/CNRS 6236, Medical Faculty, Mediterranean University, Marseille, France and Dakar, Senegal
| | - Florence Fenollar
- URMITE, UMR IRD 198/CNRS 6236, Medical Faculty, Mediterranean University, Marseille, France and Dakar, Senegal
| | - Cheikh Sokhna
- URMITE, UMR IRD 198/CNRS 6236, Medical Faculty, Mediterranean University, Marseille, France and Dakar, Senegal
| | - Jean-François Trape
- URMITE, UMR IRD 198/CNRS 6236, Medical Faculty, Mediterranean University, Marseille, France and Dakar, Senegal
| | - Didier Raoult
- URMITE, UMR IRD 198/CNRS 6236, Medical Faculty, Mediterranean University, Marseille, France and Dakar, Senegal
- * E-mail:
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90
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Pages F, Faulde M, Orlandi-Pradines E, Parola P. The past and present threat of vector-borne diseases in deployed troops. Clin Microbiol Infect 2010; 16:209-24. [PMID: 20222896 DOI: 10.1111/j.1469-0691.2009.03132.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
From time immemorial, vector-borne diseases have severely reduced the fighting capacity of armies and caused suspension or cancellation of military operations. Since World War I, infectious diseases have no longer been the main causes of morbidity and mortality among soldiers. However, most recent conflicts involving Western armies have occurred overseas, increasing the risk of vector-borne disease for the soldiers and for the displaced populations. The threat of vector-borne disease has changed with the progress in hygiene and disease control within the military: some diseases have lost their military significance (e.g. plague, yellow fever, and epidemic typhus); others remain of concern (e.g. malaria and dengue fever); and new potential threats have appeared (e.g. West Nile encephalitis and chikungunya fever). For this reason, vector control and personal protection strategies are always major requirements in ensuring the operational readiness of armed forces. Scientific progress has allowed a reduction in the impact of arthropod-borne diseases on military forces, but the threat is always present, and a failure in the context of vector control or in the application of personal protection measures could allow these diseases to have the same devastating impact on human health and military readiness as they did in the past.
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Affiliation(s)
- F Pages
- Institut de Recherche Biomédicale des Armées, antenne de Marseille, Marseille, France.
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91
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Bouattour A, Garnier M, M'Ghirbi Y, Sarih M, Gern L, Ferquel E, Postic D, Cornet M. Borrelia crocidurae infection of Ornithodoros erraticus (Lucas, 1849) ticks in Tunisia. Vector Borne Zoonotic Dis 2010; 10:825-30. [PMID: 20420529 DOI: 10.1089/vbz.2009.0151] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Tick-borne relapsing fever (TBRF) is caused by Borrelia species transmitted to humans by infected Ornithodoros sp. ticks. The disease has been rarely described in North Africa, and in Tunisia the local transmission of TBRF seems to have disappeared or is undiagnosed. A longitudinal study was conducted in 14 sites located in four different bioclimatic zones of Tunisia to assess both the distribution of Ornithodoros sp. and their infection rate with the relapsing fever Borrelia sp. Three polymerase chain reaction methods targeting the 16S rRNA, the intergenic spacer, and the fla (flagellin) genes were used and phylogenetic analyses were carried out. Three hundred and fifty-eight specimens of Ornithodoros were collected: O. erraticus (previously termed "small variety") (n = 190) and O. normandi (n = 168). Borrelia crocidurae DNA was detected in 15.1% of O. erraticus (small variety) (24 out of the 159 randomly selected for testing) collected in rodent burrows situated in the arid and Saharan areas in southern Tunisia. Molecular analysis targeting the 16S rRNA gene and the noncoding intergenic spacer domain showed good resolution for this Borrelia sp., although no molecular polymorphism was evidenced according to location. In contrast, none of the 133 O. normandi, also randomly selected for testing, was infected by Borrelia sp. and these ticks were restricted to the subhumid and semiarid zones in northern Tunisia. Both O. erraticus (small variety) and O. normandi were found in Tunisia and the high B. crocidurae infection rate found in O. erraticus highlights the risk of TBRF transmission in the southern part of the country.
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Affiliation(s)
- Ali Bouattour
- Service d'Entomologie Médicale, Institut Pasteur de Tunis, Tunis, Tunisia.
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92
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Mediannikov O, Fenollar F, Socolovschi C, Diatta G, Bassene H, Molez JF, Sokhna C, Trape JF, Raoult D. Coxiella burnetii in humans and ticks in rural Senegal. PLoS Negl Trop Dis 2010; 4:e654. [PMID: 20386603 PMCID: PMC2850317 DOI: 10.1371/journal.pntd.0000654] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Accepted: 03/02/2010] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Q fever is a worldwide zoonotic disease caused by Coxiella burnetii. Epidemiologically, animals are considered reservoirs and humans incidental hosts. METHODOLOGY/PRINCIPAL FINDINGS We investigated Q fever in rural Senegal. Human samples (e.g., sera, saliva, breast milk, feces) were screened in the generally healthy population of two villages of the Sine-Saloum region. Ticks were collected in four regions. Seroprevalence was studied by immunofluorescence, and all other samples were tested by two qPCR systems for detection of C. burnetii. Positive samples were genotyped (multispacer typing) by amplification and sequencing of three spacers. Strains were isolated by cell culture. We found that the seroprevalence may be as high as 24.5% (59 of 238 studied) in Dielmo village. We identified spontaneous excretion of C. burnetii by humans through faeces and milk. Hard and soft ticks (8 species) were infected in 0-37.6%. We identified three genotypes of C. burnetii. The previously identified genotype 6 was the most common in ticks in all studied regions and the only one found in human samples. Three strains of genotype 6 of C. burnetii were also recovered from soft tick Ornithodoros sonrai. Two other genotypes found in ticks, 35 and 36, were identified for the first time. CONCLUSIONS/SIGNIFICANCE Q fever should be considered a significant public health threat in Senegal. Humans, similar to other mammals, may continuously excrete C. burnetii.
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Affiliation(s)
- Oleg Mediannikov
- URMITE, UMR IRD 198/CNRS 6236, Mediterranean University, Medical Faculty, Marseille, France
| | - Florence Fenollar
- URMITE, UMR IRD 198/CNRS 6236, Mediterranean University, Medical Faculty, Marseille, France
| | - Cristina Socolovschi
- URMITE, UMR IRD 198/CNRS 6236, Mediterranean University, Medical Faculty, Marseille, France
| | | | | | | | | | | | - Didier Raoult
- URMITE, UMR IRD 198/CNRS 6236, Mediterranean University, Medical Faculty, Marseille, France
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94
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Concomitant infection decreases the malaria burden but escalates relapsing fever borreliosis. Infect Immun 2010; 78:1924-30. [PMID: 20145098 DOI: 10.1128/iai.01082-09] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
About 500 million cases of malaria occur annually. However, a substantial number of patients who actually have relapsing fever (RF) Borrelia infection can be misdiagnosed with malaria due to similar manifestations and geographic distributions of the two diseases. More alarmingly, a high prevalence of concomitant infections with malaria and RF Borrelia has been reported. Therefore, we used a mouse model to study the effects of such mixed infection. We observed a 21-fold increase in spirochete titers, whereas the numbers of parasitized erythrocytes were reduced 15-fold. This may be explained by polarization of the host immune response toward the intracellular malaria parasite, resulting in unaffected extracellular spirochetes and hosts that succumb to sepsis. Mixed infection also resulted in severe malaria anemia with low hemoglobin levels, even though the parasite counts were low. Overall, coinfected animals had a higher fatality rate and shorter time to death than those with either malaria or RF single infection. Furthermore, secondary malaria infection reactivated a quiescent RF brain infection, which is the first evidence of a clinically and biologically relevant cue for reactivation of RF Borrelia infection. Our study highlights the importance of investigating concomitant infections in vivo to elucidate the immune responses that are involved in the clinical outcome.
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95
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Sarih M, Garnier M, Boudebouch N, Bouattour A, Rihani A, Hassar M, Gern L, Postic D, Cornet M. Borrelia hispanica relapsing fever, Morocco. Emerg Infect Dis 2010; 15:1626-9. [PMID: 19861058 PMCID: PMC2866405 DOI: 10.3201/eid1510.090403] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We found that 20.5% of patients with an unexplained fever in northwestern Morocco had tick-borne relapsing fever. Molecular detection specific for the 16S rRNA gene identified Borrelia hispanica. The noncoding intergenic spacer sequence domain showed high sensitivity and good resolution for this species.
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96
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Warrell DA. Relapsing fevers. Infect Dis (Lond) 2010. [DOI: 10.1016/b978-0-323-04579-7.00125-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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97
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Abstract
PURPOSE OF REVIEW Relapsing fever has the highest incidence of any bacterial disease in Africa and a massive epidemic potential due to current political turmoil in the Horn of Africa. This review focuses on recent advances in diagnostics, molecular biology and host-pathogen interactions. RECENT FINDINGS Complete relapsing fever genomes have recently been published, and the first site-specific genetic knockout complementation has been performed. Relapsing fever has gone from being a neglected disease to garnering interest in aspects such as tissue invasion, membrane biochemistry and complement evasion. Relapsing fever symptoms are variable, and the disease is commonly misdiagnosed as, for example, malaria. Although relapsing fever is considered a transient disease, it persists as a residual infection in the brain, which can be reactivated on immunosuppression. Therefore, single-dose antibiotic treatment should be avoided. Instead, treatment should cover a longer period, similar to the recommended regime for Lyme disease. Relapsing fever is a common cause of pregnancy complications such as intrauterine growth retardation and placental damage with spirochaetes crossing the maternal-foetal barrier, resulting in congenital infection. SUMMARY Although relapsing fever remains a big problem, recently described host-pathogen interactions, diagnostics and molecular biology advances such as completed genome sequences and the dawn of genetic tools have brought relapsing fever research into the 21st century.
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98
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Sánchez‐Vizcaíno JM, Martínez‐López B, Martínez‐Avilés M, Martins C, Boinas F, Vialc L, Michaud V, Jori F, Etter E, Albina E, Roger F. Scientific review on African Swine Fever. ACTA ACUST UNITED AC 2009. [DOI: 10.2903/sp.efsa.2009.en-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
| | | | | | - Carlos Martins
- Faculdade de Medicina Veterinaria, Universidade Técnica de Lisboa, (FMV‐UTL)
| | - Fernando Boinas
- Faculdade de Medicina Veterinaria, Universidade Técnica de Lisboa, (FMV‐UTL)
| | - Laurence Vialc
- Centre de Cooperation Internationale en Recherche Agronomique pour le Développement (CIRAD)
| | - Vincent Michaud
- Centre de Cooperation Internationale en Recherche Agronomique pour le Développement (CIRAD)
| | - Ferran Jori
- Centre de Cooperation Internationale en Recherche Agronomique pour le Développement (CIRAD)
| | - Eric Etter
- Centre de Cooperation Internationale en Recherche Agronomique pour le Développement (CIRAD)
| | - Emmanuel Albina
- Centre de Cooperation Internationale en Recherche Agronomique pour le Développement (CIRAD)
| | - François Roger
- Centre de Cooperation Internationale en Recherche Agronomique pour le Développement (CIRAD)
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Fenollar F, Trape JF, Bassene H, Sokhna C, Raoult D. Tropheryma whipplei in fecal samples from children, Senegal. Emerg Infect Dis 2009; 15:922-4. [PMID: 19523292 PMCID: PMC2727305 DOI: 10.3201/eid1506.090182] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We tested fecal samples from 150 healthy children 2–10 years of age who lived in rural Senegal and found the prevalence of Tropherymawhipplei was 44%. Unique genotypes were associated with this bacterium. Our findings suggest that T. whipplei is emerging as a highly prevalent pathogen in sub-Saharan Africa.
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Hotez PJ, Kamath A. Neglected tropical diseases in sub-saharan Africa: review of their prevalence, distribution, and disease burden. PLoS Negl Trop Dis 2009; 3:e412. [PMID: 19707588 PMCID: PMC2727001 DOI: 10.1371/journal.pntd.0000412] [Citation(s) in RCA: 736] [Impact Index Per Article: 49.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The neglected tropical diseases (NTDs) are the most common conditions affecting the poorest 500 million people living in sub-Saharan Africa (SSA), and together produce a burden of disease that may be equivalent to up to one-half of SSA's malaria disease burden and more than double that caused by tuberculosis. Approximately 85% of the NTD disease burden results from helminth infections. Hookworm infection occurs in almost half of SSA's poorest people, including 40-50 million school-aged children and 7 million pregnant women in whom it is a leading cause of anemia. Schistosomiasis is the second most prevalent NTD after hookworm (192 million cases), accounting for 93% of the world's number of cases and possibly associated with increased horizontal transmission of HIV/AIDS. Lymphatic filariasis (46-51 million cases) and onchocerciasis (37 million cases) are also widespread in SSA, each disease representing a significant cause of disability and reduction in the region's agricultural productivity. There is a dearth of information on Africa's non-helminth NTDs. The protozoan infections, human African trypanosomiasis and visceral leishmaniasis, affect almost 100,000 people, primarily in areas of conflict in SSA where they cause high mortality, and where trachoma is the most prevalent bacterial NTD (30 million cases). However, there are little or no data on some very important protozoan infections, e.g., amebiasis and toxoplasmosis; bacterial infections, e.g., typhoid fever and non-typhoidal salmonellosis, the tick-borne bacterial zoonoses, and non-tuberculosis mycobaterial infections; and arboviral infections. Thus, the overall burden of Africa's NTDs may be severely underestimated. A full assessment is an important step for disease control priorities, particularly in Nigeria and the Democratic Republic of Congo, where the greatest number of NTDs may occur.
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Affiliation(s)
- Peter J. Hotez
- Department of Microbiology, Immunology, and Tropical Medicine, The George Washington University, Washington, D.C., United States of America
- Sabin Vaccine Institute, Washington, D.C., United States of America
- * E-mail: or (PJH)
| | - Aruna Kamath
- Department of Microbiology, Immunology, and Tropical Medicine, The George Washington University, Washington, D.C., United States of America
- Sabin Vaccine Institute, Washington, D.C., United States of America
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