HISTORIA CLÍNICA

• Mayo de 2010: un cliente de Pina de Ebro (comarca Ribera Baja del

Ebro, Zaragoza), solicita la asistencia del Servicio de Diagnóstico

Clínico de Rumiantes de la Facultad de Veterinaria de Zaragoza.

• Observa:– Intranquilidad anormal del rebaño cuando sale a los pastos próximos a

la orilla del río.

– Los animales apenas comen.

– Pérdida de condición corporal del rebaño.

VISITA A LA EXPLOTACIÓNLos animales:

• Están intranquilos y se agrupan en exceso.

• Sufren espantadas.

• Presentan pataleos continuados y muy acentuados.

• Producen una nube de polvo cuando descansaban en terreno seco.

• Presentan movimientos desmesurados de orejas y rabo.

• Algunos presentan postración esternal, quedando apartados del rebaño .

Además:

• Una densa nube de insectos rodea al rebaño.

• Durante la visita sufrimos las picaduras de estos “mosquitos”.

• Habitantes del pueblo habían acudido al médico como consecuencia de “picaduras”.

EXPLORACIÓN FÍSICA

• “Mordeduras”, especialmente en cabeza, cuello, extremidades, zona mamaria, zona perianal y testicular, bajo vientre.

• Zonas afectadas: reacción inflamatoria local, en ocasiones muy importante, con un punto central (a veces sangrante).

• Presencia de insectos succionando sangre. Se capturaron para su identificación.

SEGUNDA VISITA A LA EXPLOTACIÓN

• Se buscan estadios puparios y larvarios, en las plantas de la orilla del río Ebro (corriente de agua).

• Se toman muestras para su clasificación.

RESULTADOS DE LA IDENTIFICACIÓN

• Insectos de la familia Simuliidae (“Mosca negra”).– En algunas especies: hembras hematófagas.

– Hábitos diurnos (picaduras durante el día).

• La especie se determina por la observación de los estadios puparios.

SEGUNDA VISITA A LA EXPLOTACIÓN

• Búsqueda de los estadios puparios y larvarios en las plantas de la orilla del río Ebro (corriente de agua).

• Se tomaron muestras para hacer una clasificación.

Se detectaron tres especies diferentes:

• Simulium (Wihelmia) equinum.

• Simulium (Wihelmia) sergenti.

• Simulium (Boophthora) erytrocephalum.

Queda confirmada la presencia de la mosca negra en el tramo medio

del río Ebro, a escasos kilómetros de Zaragoza capital (riesgo para

la población).

RESULTADOSDE LA CLASIFICACIÓN

RECOMENDACIONES

• Pastoreo nocturno.

• Insecticidas-repelentes “pour on” para minimizar el número de ataques.

• Uso de repelentes para evitar las picaduras a los humanos.

BIBLIOGRAFÍA RECOMENDADA• Shelley AJ, Hernández LM, Davies JB. Blackflies (Diptera: Simuliidae) of Southern

Guyana with keys for the identification of adults and pupae-a review. 2004. Mem Inst

Oswaldo Cruz, 99:443-470.

Abstract

A revision is made of the previously poorly studied blackfly fauna from the south-western

border of Guyana with Brazil. Notes on the biosystematics of the species found are

provided, together with keys and illustrations based on their morphology. Of the 14

species recorded, eight are anthropophilic and two of these (Simulium oyapockense

s.l. and S. guianense s.l.) are proven vectors of human onchocerciasis in the nearby

Amazonia focus of the disease in neighbouring Brazil.

• Myburgh E, Nevill EM. Review of blackfly (Diptera: Simuliidae) control in South Africa.

2003. Onderstepoort J Vet Res, 70:307-316.

AbstractThe medical, veterinary and economic importance of blackflies in South Africa, and the historical development

of blackfly control programmes in various South African rivers, are reviewed in this paper. In 1996 it was

estimated that blackflies can cause more than R 88 million damages per annum along the middle and

lower Orange River where Simulium chutteri is considered the main pest species. A clear link between

the construction of dams and the spread of the blackfly problem was shown. Four phases characterize

the development of blackfly control in South Africa: (1) during the 1960s blackflies in the Vaal River were

controlled with DDT; (2), during the 1970s and into the 1980s blackflies were controlled using water-flow

manipulation; (3) when used at strategic times, water-flow manipulation could be used to enhance the

effect of natural predator populations; and (4) during the 1990s the organophosphate temephos and

toxins produced by the bacterium Bacillus thuringiensis var. israelensis were tested for their efficacy

against blackflies. The larvicides temephos and B. thuringiensis proved to be effective and are still used

in several control programmes. The latest research focuses on the factors that influence adult blackfly

survival and annoyance, as well as the development of methods that can be used to protect sheep from

blackfly attacks.

• Braverman Y. Nematocera (Ceratopogonidae, Psychodidae, Simuliidae and Culicid)

and control methods. 1994. Rev Sci Tech, 13:1175-1199.

AbstractThe biology, veterinary importance and control of certain Nematocera are described and discussed.

Culicoides spp. (family Ceratopogonidae) transmit the arboviruses of bluetongue (BT), African horse sickness (AHS), bovine ephemeral fever (BEF) and Akabane. Some other arboviruses have been isolated from these species, while fowl pox has been transmitted experimentally by Culicoides. These insects are vectors of the parasitic protozoans Leucocytozoon caulleryi and Haemoproteus nettionis, and the parasitic nematodes Onchocerca gutturosa, O. gibsoni and O. cervicalis. They also cause recurrent summer hypersensitivity in horses, ponies, donkeys, cattle and sheep. Farm animals can die as a result of mass attack by Simulium spp., which are also vectors of Leucocytozoon simondi, L. smithi and the filariae O. gutturosa, O. linealis and O. ochengi. Venezuelan equine encephalomyelitis (VEE) and Rift Valley fever (RVF) have been isolated from simuliids, and vesicular stomatitis virus New Jersey strain has been replicated in Simulium vittatum. Simuliids are well known as vectors of O. volvulus, the cause of human onchocercosis (river blindness). The family Psychodidae includes the genera Phlebotomus and Lutzomyia (subfamily Phlebotominae), vectors of Leishmania spp. in humans, dogs and other mammals. Vesicular stomatitis virus Indiana strain has been regularly isolated from phlebotomine sandflies. Mass attack by mosquitoes can also prove fatal to farm animals. Mosquitoes are vectors of the viruses of Akabane, BEF, RVF, Japanese encephalitis, VEE, western equine encephalomyelitis, eastern equine encephalomyelitis and west Nile meningoencephalitis, secondary vectors of AHS and suspected vectors of Israel turkey meningoencephalitis. The viruses of hog cholera, fowl pox and reticuloendotheliosis, the rickettsiae Eperythrozoon ovis and E. suis, and the bacterium Borrelia anserina are mechanically transmitted by mosquitoes. These insects also induce allergic dermatitis in horses. They transmit several filarial worms of both animals and humans, and are of great medical importance as vectors of major human diseases, including malaria, yellow fever, dengue fever and many more diseases caused by arboviruses.

• Beaucournu JC, Beaucournu-Saguez F, Chevrier S. Human simuliidosis in France: antiquity, anthropophilic species. 1992. Ann Parasitol Hum Comp., 67:202-208.

Abstract

The problem of the human Simuliidosis (caused by black flies) is

reviewed for the France: important and, perhaps, relatively

recent increase from the known human attacks by black flies.

Countries and anthropophilic species are cited.

• Niesiołowski S.Sanitary and economic significance of black flies

(Simuliidae, Diptera) and the current state of research on these

insects in poland. 1980. Wiad Parazytol, 26:663-677.

AbstractA review is presented of studies in Poland on the medical and veterinary

importance of Simuliidae in the transmission of disease and losses of

livestock caused by their bites. The most harmful simuliids occurring in

Poland are Simulium erythrocephalum (Deg.) (Boophthora

erythrocephala), S. pusillum Fries (Schoenbaueria pusilla), Simulium

equinum (L.) (Wilhelmia equina), S. lineatum (Mg.) (W. salopiensis

(Edw.)), S. ornatum Mg. (Odagmia ornata) and S. galeratum Edw. Their

control is also discussed.

AUTORES• Borobia, Marta• Figueras, Luis• Ruiz, Ignacio• Lacasta, Delia

• Revisado por Juan José Ramos y Aurora Ortín:Departamento de Patología Animal. Facultad de Veterinaria. Universidad de Zaragoza.