Leptospira spp . AND Toxoplasma gondii ANTIBODIES IN VAMPIRE BATS ( Desmodus rotundus ) IN BOTUCATU REGION , SP ,

The destruction of natural ecosystems has caused several problems to humans and other animals; herein we investigate the close relationship among vampire bats, humans and domestic animals. Toxoplasma gondii and Leptospira spp. infections are two worldwide zoonoses that provoke serious damage to animals. To determine the prevalence of bats seropositive for toxoplasmosis and leptospirosis in the Botucatu region, 204 serum samples of vampire bats (Desmodus rotundus) were tested for T. gondii antibodies by modified agglutination test (MAT-t) and for Leptospira spp. by microscopic agglutination test (MAT-l). No animal was tested positive for T. gondii while leptospiral positivity was 7.8% for Pyrogenes, Shermani and Javanica serovars, with titers varying from 100 to 1,600. Thus, it was verified that D. rotundus does not play a relevant role in toxoplasmosis epidemiology. However, these bats can be important in the maintenance of Leptospira spp. in the environment.


INTRODUCTION
Chiropterans are one of the most distinct mammals that play an important role in nature spreading seeds, pollinating flowers and controlling the insect population (1,2).D. rotundus individuals are found in colonies of 20 to 100 that may use caves, tree holes, abandoned mines, house basements, drainpipes, etc. as roosts (3,4).
The presence of vampire bats near residences and livestock in the Botucatu municipality, favored by the creation of several embankments during the construction of Castelo Branco highway with many areas of water drainage pipes, has contributed to the dissemination of many infectious diseases, including toxoplasmosis and leptospirosis, thus constituting a great public health problem (5).
Toxoplasmosis is a parasitic zoonosis caused by Toxoplasma gondii protozoan that presents a worldwide distribution.Moreover, a great part of the human and animal populations is infected by T. gondii (6,7).Chiropterans may be infected by ingestion of oocysts present in the environment, food or water contaminated by feces of infected felids; by consumption of bradyzoites present in tissue of infected intermediate hosts; and also by the transmission of tachyzoites via the transplacental route.
Leptospiral infection is another global zoonosis caused by a spirochaeta, namely, Leptospira spp.(8).This bacterium colonizes the kidneys of reservoir animals and is eliminated in their urine.Humans and other animals get infected either directly or indirectly, through skin, oral, nasal or conjunctiva mucosae; however, humans represent a dead-end as accidental hosts (9,10).The most common transmission routes are water, soil and food contaminated with urine of infected animals.Contaminated bats constitute a significant infection source since they can carry leptospires (11,12).Matthias et al. (13) reported that renal infection rates may differ among bat genera, and that parasitic burden was most frequent in the kidneys of Promops, Desmodus and Myotis that tested positive by PCR in the following respective percentages: 100%, 50% and 33%.These animals excrete the agent in urine, thus contaminating the environment or even their victims (animals or humans), as they have the habit of urinating while feeding, because wounds caused by vampire bats are a gateway for this bacterium.The possibility that D. rotundus may feed on blood of a leptospiremic animal and therefore get infected, should also be considered.Regarding toxosplasmosis, modified agglutination test (MAT-t) was performed according to Desmonts and Remington (15).
All serum samples were negative to toxoplasmosis and 7.84% reacted to different leptospiral serovars, with titers ranging from 100 to 1600 (Table 1).The toxoplasmosis results agree with Smith and Frenkel ( 16), who while studying the occurrence of antibodies against T. gondii in insectivorous bats, verified also negative results to Sabin-Feldman dye test in one big brown bat (Eptesicus fuscus), one red bat (Lasiurus borealis), and two evening bats (Nycticeius humeralis).These findings indicate that bats may be infected, but with lower probability than other mammals.
The negative results concerning T. gondii were probably due to the fact that vampire bats do not usually have any contact with the soil, where infectious oocysts are found.They only ingest their prey blood and have no contact with bradyzoites DNA suggests that leptospires are more prevalent in flying fox populations than would be expected for a species that is not a carrier.
Thus, the results allow us to conclude that D. rotundus, and probably all other bat species, do not play a leading role in the maintenance or transmission of T. gondii to humans and to other animals.Further studies should be conducted to establish the role of these animals as Leptospira spp.reservoirs.

Table 1 .
MAT-l results of the studied Desmodus rotundus, with respective serovars and reactive titers N.: number of animals; MAT-l: microscopic agglutination test for Leptospira spp.
(18)n CB et al.Leptospira spp.And Toxoplasma gondii antibodies in vampire bats (Desmodus rotundus) in Botucatu region, SP, Brazil.J Venom Anim Toxins incl Trop Dis.2009;15(3):550present in cysts.Thus, infection would only be possible by ingesting blood of an animal at an acute stage of the disease with flowing tachyzoites, which rarely occurs because toxoplasmosis is mostly a chronic disease.In a study conducted by Smythe et al.(17)in Australia, 28% of the frugivorous or nectarivorous bats belonging to the genus Pteropus exhibited antibodies for Cox et al.(18)studying Australian flying foxes (Pteropus spp.), found in 11% of kidney samples Leptospira spp., which indicates that flying foxes, known as fruit bats, are carriers of this pathogen.The identification of one in ten animals with leptospiral