Febre maculosa no município de Pedreira - Estado de São Paulo - Brasil - relação entre ocorrência de casos e parasitismo humano por ixodídeos

Lima, Victor Luiz de Souza; Figueiredo, A C; Pignatti, Marta Gislene; Módolo, Marcelo

doi:10.1590/s0037-86821995000200010

Cited by 23 publications

(20 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…acts as the primary vector in parts of the Southwest. Conversely, in Central and South America several species of the genus Amblyomma act as vectors and reservoirs of the pathogen (Bustamante and Varela, 1946; de Rodaniche, 1953; Lima et al, 1995; de Lemos et al, 1997; Pinter and Labruna, 2006; Labruna et al, 2008; Paddock et al, 2008; Labruna, 2009; Dzul-Rosado et al, 2013). …”

Section: Discussionmentioning

confidence: 99%

Vector competence of Amblyomma americanum (Acari: Ixodidae) for Rickettsia rickettsii

Levin

Zemtsova

Killmaster

et al. 2017

Ticks and Tick-borne Diseases

View full text Add to dashboard Cite

Rickettsia rickettsii – the etiologic agent of Rocky Mountain spotted fever (RMSF) – is widely spread across the Americas. In the US, Dermacentor spp. ticks are identified as primary vectors of R. rickettsii and Rhipicephalus sanguineus s.l. has been implicated in transmission of this pathogen in several locations in the Southwest. Conversely, ticks of the genus Amblyomma are recognized vectors of RMSF in Central and South America, but not in the US. A. americanum is one of the most aggressive human-biting ticks in the US, whose geographical range overlaps with that of reported RMSF cases. Despite sporadic findings of R. rickettsii DNA in field-collected A. americanum and circumstantial association of this species with human RMSF cases, its vector competence for R. rickettsii has not been appropriately studied. Therefore, we assessed the ability of A. americanum to acquire and transmit two geographically distant isolates of R. rickettsii. The Di-6 isolate of R. rickettsii used in this study originated in Virginia and the AZ-3 isolate originated in Arizona. Under laboratory conditions, A. americanum demonstrated vector competence for both isolates, although the efficiency of acquisition and transovarial transmission was higher for Di-6 than for AZ-3 isolate. Uninfected larvae acquired the pathogen from systemically infected guinea pigs, as well as while feeding side by side with Rickettsia-infected ticks on non-rickettsiemic hosts. Once acquired, R. rickettsii was successfully maintained through the tick molting process and transmitted to susceptible animals during subsequent feedings. Guinea pigs and dogs infested with infected A. americanum developed fever, scrotal edema and dermatitis or macular rash. R. rickettsii DNA was identified in animal blood, skin, and internal organs. The prevalence of infection within tick cohorts gradually increased due to side-by-side feeding of infected and uninfected individuals from 33 to 49% in freshly molted nymphs to 71–98% in engorged females. Moreover, R. rickettsii was transmitted transovarially by approximately 28% and 14% of females infected with Di-6 and AZ-3 isolates, respectively. Hence, A. americanum is capable of acquiring, maintaining and transmitting R. rickettsii isolates originating from two different geographical regions of the US, at least under laboratory conditions. Its role in ecology and epidemiology of RMSF in the US deserves further investigation.

show abstract

Section: Discussionmentioning

confidence: 99%

Vector competence of Amblyomma americanum (Acari: Ixodidae) for Rickettsia rickettsii

Levin

Zemtsova

Killmaster

et al. 2017

Ticks and Tick-borne Diseases

View full text Add to dashboard Cite

show abstract

“…Up until that moment, there had been no records of the condition in the region 16 . From 1986 onward, cases of BSF have been confirmed in other cities of the region, with the progressive notification of cases after 1996 as well as the amplification of the transmission area; then it became a compulsory notification disease.…”

Section: Introductionmentioning

confidence: 99%

Urbanization of Brazilian spotted fever in a municipality of the southeastern region: epidemiology and spatial distribution

Nasser

Lana²,

Silva³

et al. 2015

Rev. bras. epidemiol.

View full text Add to dashboard Cite

Introduction: Brazilian spotted fever is an emerging zoonosis notified mainly in the Southeast of Brazil, especially due to its high level of lethality. Objective: To analyze the epidemiological and spatial pattern of the disease in the municipality of Valinhos (106,793 inhabitants), São Paulo, Southeastern region of Brazil, in the period between 2001 and 2012. Methods: All laboratory-confirmed cases with likely site of infection in the city (n = 49) notified in the Brazilian Case Registry Database were studied. Sites were geocoded using the cartographic base of the city and Google Earth (geographic coordinates) with correction according to the Brazilian Geodetic System. We used the Kernel estimator to analyze the density of the cases on the map. Land cover and distance to basins of all cases were analyzed. Information about tick species and primary hosts were obtained from reports of the Superintendence of Control of Endemic Diseases. Results: Seasonality of the disease was observed with the highest incidence from June to November, and in 2005 and 2011. The most affected groups were men (79.6%) aged 20-49 years old (49%). Lethality was found to be 42.9%. Maps showed the progressive registration of cases in the urban area. Capybaras were reported as the main primary host, and Amblyomma cajennense was identified in probable sites of infection during field investigation. The likely sites of infection were mostly located near basins, dirty pastures, and bordering woods. Conclusions: The transmission pattern of Brazilian spotted fever in Valinhos is similar to that in other cities in the region, where capybara is the main primary host and an amplifier of R. rickettsii. Over the years, a higher occurrence of cases has been identified in the urban area of the city.

show abstract

“…The disease was described for the first time in 1929, in the states of São Paulo and Minas Gerais. One of the theories for explaining the incidence of this disease was a growth in the population of the natural reservoirs of rickettsia (protected by the hunting prohibition, principally for capybara) contributing to the infestation of infected ticks disseminating the disease around areas inhabited by humans and domestic animals [27]. During the period of 1995 to 2003, 241 cases were confirmed.…”

mentioning

confidence: 99%

Emerging and reemerging diseases in Brazil: data of a recent history of risks and uncertainties

Cardoso¹,

Navarro²

2007

Braz J Infect Dis

View full text Add to dashboard Cite

This article discusses the emergence and reemergence of infectious diseases on the basis of a review of the literature. It shows the critical situations faced worldwide and in special Brazil's susceptible position due to its complexity, mostly represented by the mega-biodiversity of the country and its socio-economic problems directly affecting public health. It approaches the discussions around the issue with emphasis to the recommended investments in the health sector, directed to surveillance and to strengthening the epidemiological, laboratorial and clinical bases and centered on preventive and control measures in the affected areas including Biosafety.

show abstract

Febre maculosa no município de Pedreira - Estado de São Paulo - Brasil - relação entre ocorrência de casos e parasitismo humano por ixodídeos

Abstract: A febre maculosa foi identificada no Estado de Sâo Paulo e Minas Gerais na primeira metade deste século38914.

Cited by 23 publications

References 5 publications

Vector competence of Amblyomma americanum (Acari: Ixodidae) for Rickettsia rickettsii

Vector competence of Amblyomma americanum (Acari: Ixodidae) for Rickettsia rickettsii

Urbanization of Brazilian spotted fever in a municipality of the southeastern region: epidemiology and spatial distribution

Emerging and reemerging diseases in Brazil: data of a recent history of risks and uncertainties

Contact Info

Product

Resources

About