Dogs with divergent serology for visceral leishmaniasis as sources of Leishmania infection for Lutzomyia longipalpis phlebotomine sand flies – an observational study in an endemic area in Brazil

Abstract Among neglected tropical diseases, visceral leishmaniasis (VL) shows great relevance in global terms and is a serious public health concern due to the possibility of severe and lethal forms in humans. In this study, we evaluate entomological factors such as diversity and abundance of phlebotomine sand flies (Diptera:Psychodidae) and the Leishmania species circulating in these species in possible association with VL transmission in the Brazilian town Itaúna. The entomological collections were performed during three consecutive nights, always in the third week of each month, within a period of 12 mo. A total of 1,786 sand fly specimens were collected, from which 20% were collected inside houses. The influence of three local climatic variables (temperature, rainfall, relative humidity) on the population sizes of these insects was evaluated. Temperature was the most influential factor, with a significant positive correlation with the local population size of phlebotomine sand flies collected per month. Lutzomyia longipalpis (Lutz & Neiva, 1912) was the predominant species in the study area. Leishmania DNA was detected in nine out of 133 pools of sand fly females, using nested/PCR, which resulted in a minimal natural infection rate of 2.91%. DNA from Leishmania infantum Nicolle, 1908 (Kinetoplastida: Trypanosomatida), was detected in Evandromyia cortelezzii (Bréthes, 1923), Ev. evandroi (Costa, Lima & Antunes, 1936), Ev. lenti (Mangabeira, 1938), and Ev. termitophila (Martins, Falcão & Silva, 1964), besides Lu. longipalpis. Our study indicates favorable conditions for VL spreading in Itaúna due to the presence of Lu. longipalpis and Le. infantum-infected phlebotomine sand flies.

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Ecology of Lutzomyia longipalpis and Lutzomyia migonei in an endemic area for visceral leishmaniasis

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612014068 ◽

2014 ◽

Vol 23 (3) ◽

pp. 320-327 ◽

Cited By ~ 11

Author(s):

Rafaella Albuquerque Silva ◽

Fabricio Kassio Moura Santos ◽

Lindemberg Caranha de Sousa ◽

Elizabeth Ferreira Rangel ◽

Claudia Maria Leal Bevilaqua

Keyword(s):

Visceral Leishmaniasis ◽

Leishmania Infantum ◽

Indoor Environment ◽

Endemic Area ◽

Natural Infection ◽

Sampling Site ◽

Lutzomyia Longipalpis ◽

Sand Flies ◽

Sampling Points ◽

Lutzomyia Migonei

The main vector for visceral leishmaniasis (VL) in Brazil is Lutzomyia longipalpis. However, the absence of L. longipalpis in a region of autochthonous VL demonstrates the participation of other species in the transmission of the parasite. Studies conducted in La Banda, Argentina, and São Vicente Férrer, Pernambuco State, Brazil, have correlated the absence of L. longipalpisand the presence of L. migonei with autochthonous cases of VL. In São Vicente Férrer, Pernambuco, there was evidence for the natural infection of L. migonei with Leishmania infantum chagasi. Thus, the objective of this work was to assess the ecology of the sand flies L. longipalpis and L. migonei in Fortaleza, an endemic area for VL. Insect capture was conducted at 22 sampling points distributed across four regions of Fortaleza. In total, 32,403 sand flies were captured; of these, 18,166 (56%) were identified as L. longipalpis and 14,237 (44%) as L. migonei. There were significant density differences found between the vectors at each sampling site (indoors and outdoors) (p <0.0001). These findings confirm that L. migonei and L. longipalpis are distributed throughout Fortaleza, where they have adapted to an indoor environment, and suggest that L. migonei may share the role as a vector with L. longipalpis in the transmission of VL in Fortaleza.

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Assessment of sand fly (Diptera, Psychodidae) control using cypermethrin in an endemic area for visceral leishmaniasis, Montes Claros, Minas Gerais State, Brazil

Cadernos de Saúde Pública ◽

10.1590/s0102-311x2011001100005 ◽

2011 ◽

Vol 27 (11) ◽

pp. 2117-2123 ◽

Cited By ~ 8

Author(s):

Ricardo Andrade Barata ◽

Erika Monteiro Michalsky ◽

Ricardo Toshio Fujiwara ◽

João Carlos França-Silva ◽

Marília Fonseca Rocha ◽

...

Keyword(s):

Visceral Leishmaniasis ◽

Endemic Area ◽

Residual Effect ◽

Minas Gerais ◽

Sand Fly ◽

Lutzomyia Longipalpis ◽

Sand Flies ◽

Light Traps ◽

Minas Gerais State ◽

Transmission Area

Montes Claros in Minas Gerais State, Brazil, was considered an intense transmission area for visceral leishmaniasis. This study evaluated sand fly fauna after insecticide application. Captures were performed in 10 districts from September 2005 to August 2006 with CDC light traps inside and outside each residence. Cypermethrin was sprayed in two cycles during November/2005 and May/2006. The 636 specimens collected, belonging to 10 species, were predominantly Lutzomyia longipalpis (79%), and most frequently males (70%). The highest percentage of specimens were captured in areas surrounding domiciles (85.8%). The main species were observed to be sensitive to treatment with the insecticide. The results showed a reduction in the number of sand flies collected after use of cypermethrin in homes and annexes, and with residual effect lasting from two to four months.

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Lutzomyia longipalpis naturally infected by Leishmania (L.) chagasi in Várzea Grande, Mato Grosso State, Brazil, an area of intense transmission of visceral leishmaniasis

Cadernos de Saúde Pública ◽

10.1590/s0102-311x2010001200020 ◽

2010 ◽

Vol 26 (12) ◽

pp. 2414-2419 ◽

Cited By ~ 10

Author(s):

Nanci A. Missawa ◽

Érika Monteiro Michalsky ◽

Consuelo Latorre Fortes-Dias ◽

Edelberto Santos Dias

Keyword(s):

Visceral Leishmaniasis ◽

Polymerase Chain Reaction Amplification ◽

Natural Infection ◽

Rflp Analysis ◽

Lutzomyia Longipalpis ◽

Sand Flies ◽

Mato Grosso ◽

Phlebotomine Sand Flies ◽

Leishmania Spp ◽

Reaction Amplification

The American visceral leishmaniasis (AVL) is caused by parasites belonging to the genus Leishmania (Trypanosomatidae) and is transmitted to humans through the bite of certain species of infected phlebotomine sand flies. In this study, we investigated the natural infection ratio of Lutzomyia longipalpis, the main vector species of AVL in Brazil, in Várzea Grande, Mato Grosso State. Between July 2004 and June 2006, phlebotomine sand flies were captured in peridomestic areas using CDC light-traps. Four hundred and twenty (420) specimens of Lu. longipalpis were captured. 42 pools, containing 10 specimens of Lu. longipalpis each, were used for genomic DNA extraction and PCR (polymerase chain reaction) amplification. Leishmania spp. DNA was detected in three out of the 42 pools tested, resulting in a minimal infection ratio of 0.71%. Restriction fragment length polymorphism (RFLP) analysis indicated that Leishmania (L.) chagasi was the infective agent in the positive pools.

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Sexual and vertical transmission of visceral leishmaniasis

The Journal of Infection in Developing Countries ◽

10.3855/jidc.4108 ◽

2014 ◽

Vol 8 (04) ◽

pp. 403-407 ◽

Cited By ~ 17

Author(s):

Andreia P Turchetti ◽

Tayse D Souza ◽

Tatiane A Paixão ◽

Renato L. Santos

Keyword(s):

Visceral Leishmaniasis ◽

Vertical Transmission ◽

Leishmania Infantum ◽

Vertebrate Host ◽

Domestic Dog ◽

Sand Flies ◽

Phlebotomine Sand Flies

Visceral leishmaniasis (VL) is an important zoonosis caused by Leishmania infantum, which has in the domestic dog its principal vertebrate host. VL is usually transmitted by phlebotomine sand flies, however atypical routes of transmission have been described. In this review we discuss the the role of sexual and vertical transmissions, and their role in the maintenance of VL in canine populations.

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Study of Phlebotomine Sand Flies (Diptera: Psychodidae) Collected in a Leishmania-Endemic Area of the Metropolitan Region of Belo Horizonte, Brazil

Journal of Medical Entomology ◽

10.1603/me09127 ◽

2010 ◽

Vol 47 (6) ◽

pp. 972-976 ◽

Cited By ~ 16

Author(s):

Gustavo M. L. Carvalho ◽

Célia M. F. Gontijo ◽

Alda L. Falcão ◽

José D. Andrade Filho

Keyword(s):

Endemic Area ◽

Metropolitan Region ◽

Sand Flies ◽

Phlebotomine Sand Flies ◽

Belo Horizonte

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USE OF THE POLYMERASE CHAIN REACTION FOR THE DIAGNOSIS OF ASYMPTOMATIC Leishmania INFECTION IN A VISCERAL LEISHMANIASIS-ENDEMIC AREA

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652013000200006 ◽

2013 ◽

Vol 55 (2) ◽

pp. 101-104 ◽

Cited By ~ 17

Author(s):

Luciana Almeida Silva ◽

Héctor Dardo Romero ◽

Aline Fagundes ◽

Nédia Nehme ◽

Otávio Fernandes ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Visceral Leishmaniasis ◽

Endemic Area ◽

Asymptomatic Infection ◽

Control Measures ◽

Skin Tests ◽

Leishmania Infection ◽

Chain Reaction ◽

Serological Tests ◽

Polymerase Chain

The diagnosis of asymptomatic infection with Leishmania (Leishmania) chagasi has become more important over recent years. Expansion of visceral leishmaniasis might be associated with other routes of transmission such as transfusion, congenital or even vector transmission, and subjects with asymptomatic infection are potential reservoirs. Moreover, the identification of infection may contribute to the management of patients with immunosuppressive conditions (HIV, transplants, use of immunomodulators) and to the assessment of the effectiveness of control measures. In this study, 149 subjects living in a visceral leishmaniasis endemic area were evaluated clinically and submitted to genus-specific polymerase chain reaction (PCR), serological testing, and the Montenegro skin test. Forty-nine (32.9%) of the subjects had a positive PCR result and none of them developed the disease within a follow-up period of three years. No association was observed between the results of PCR, serological and skin tests. A positive PCR result in subjects from the endemic area did not indicate a risk of progression to visceral leishmaniasis and was not associated with a positive result in the serological tests.

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Importance of Lutzomyia longipalpis in the dynamics of transmission of canine visceral leishmaniasis in the endemic area of Porteirinha Municipality, Minas Gerais, Brazil

Veterinary Parasitology ◽

10.1016/j.vetpar.2005.05.006 ◽

2005 ◽

Vol 131 (3-4) ◽

pp. 213-220 ◽

Cited By ~ 35

Author(s):

João C. França-Silva ◽

Ricardo A. Barata ◽

Roberto T. da Costa ◽

Érika Michalsky Monteiro ◽

George L. L. Machado-Coelho ◽

...

Keyword(s):

Visceral Leishmaniasis ◽

Endemic Area ◽

Minas Gerais ◽

Lutzomyia Longipalpis ◽

Canine Visceral Leishmaniasis

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Odour of domestic dogs infected with Leishmania infantum is attractive to female but not male sand flies: evidence for parasite manipulation

10.1101/2020.11.09.374207 ◽

2020 ◽

Author(s):

Monica E. Staniek ◽

James G.C. Hamilton

Keyword(s):

Visceral Leishmaniasis ◽

Leishmania Infantum ◽

Feeding Activity ◽

Blood Feeding ◽

Human Infection ◽

T Test ◽

Domestic Dogs ◽

Lutzomyia Longipalpis ◽

Sand Flies ◽

Paired T Test

AbstractGlobally visceral leishmaniasis (VL) causes thousands of human deaths every year. In South America, the etiologic agent, Leishmania infantum, is transmitted from an infected canine reservoir to human hosts by the blood-feeding activity of the sand fly vector, predominantly, Lutzomyia longipalpis. Previous evidence from model rodent systems have suggested that the odour of infected hosts is altered by the parasite making them more attractive to the vector leading to an increased biting rate and improved transmission prospects for the pathogen. However, the effect of Le. infantum infection on the attractiveness of naturally infected dogs which are integral to human infection, has not been assessed.Hair collected from infected and uninfected dogs residing in a VL endemic city in Brazil. was entrained to collect the volatile chemical odours present in the headspace. Female and male Lu. longipalpis sand flies were offered a choice of infected or uninfected odour in a series of behavioural experiments. Control experiments established that female and male Lu. longipalpis were equally attracted to uninfected dog odour, female Lu. longipalpis were significantly more attracted to infected dog odour than uninfected dog odour in all 15 experimental replicates (average 45.7±0.87 females attracted to infected odour; 23.9±0.82 to uninfected odour; paired T-test, P=0.000). Male Lu. longipalpis did not significantly prefer either infected or uninfected odour (average 36.1±0.4 males to infected odour; 35.7±0.6 to uninfected odour; paired T-test, P=0.722). A significantly greater proportion of females chose the infected dog odour compared to the males (paired T-test, P=0.000).The results show that dogs infected with Le. infantum are significantly more attractive to blood-feeding female than male sand flies. This is strong evidence for parasite manipulation of the host odour in a natural transmission system and indicates that infected dogs may have a disproportionate significance in maintaining infection in canine and human infection.Author SummaryVisceral leishmaniasis (VL) is a disease caused by the Protist parasite Leishmania infantum. In Brazil and other South and Central American countries, the parasite is transmitted by the blood-feeding activity of infected female Lutzomyia longipalpis sand flies. The disease leads to thousands of human cases and deaths every year. Domestic dogs are the reservoir of infection for humans therefore understanding the effect of infection on dogs is important in developing an understanding of the epidemiology of the disease. Although previous studies on rodent models of Le. infantum infection have shown that infected Golden Hamsters are more attractive to Lu. longipalpis the attractiveness of naturally infected dogs to the insect vector has not been previously been investigated. In this study we showed that the odour of infected dogs is significantly more attractive to female sand flies which can transmit the pathogen than to male sand flies which do not. This clear-cut difference in attraction of female and males suggests that the females are preferentially attracted by parasite infected hosts and may lead to enhanced infection and transmission opportunities for the parasite.

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