On the longevity and behaviour of microfilariae of Wuchereria bancrofti, Brugia pahangi and Dirofilaria immitis transfused to laboratory rodents

The Culicidae family is represented by approximately 3,610 species, among which many are involved in transmission of pathogens and parasites, thus presenting great medical-veterinary importance. In Brazil, the state of Pernambuco is considered an endemic area for many diseases vectored by mosquitoes, such as human and canine filariasis, caused by Wuchereria bancrofti and Dirofilaria immitis, respectively. The aim of this study was to evaluate the occurrence of immature forms of culicids, over an one-year period, in a specific area of northeastern region of Brazil. Culicids larvae were collected from traps located on the ground and in treetops, between october 2012 and september 2013. Ten different species of culicids were identified. The greatest number of larvae were collected in september 2013 and the lowest number in december 2012. Stegomyia (Stegomyia) albopicta (46.45%; 5,908/12,718), Culex (Culex) maxi (35.56%; 4,523/12,718) and Limatus durhamii (12.58%; 1,600/12,718) were the most frequent species. The human and animal populations living in the study area are exposed to culicids and transmission agents throughout the year, especially after the rains. Therefore, control and prevention measures against culicids must be adopted in the study area.

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The Use of a Membrane Feeding Technique for Infecting Mosquitoes with Filarial Worms Transported between Laboratories

Journal of Helminthology ◽

10.1017/s0022149x00000663 ◽

1971 ◽

Vol 45 (4) ◽

pp. 415-418 ◽

Cited By ~ 9

Author(s):

T. Ponnudurai ◽

D. A. Denham ◽

G. S. Nelson

Keyword(s):

Dirofilaria Immitis ◽

Brugia Malayi ◽

Wuchereria Bancrofti ◽

Feeding System ◽

Membrane Feeding ◽

Feeding Technique

SummaryBlood containing microfilariae has been successfully transported from various laboratories to London. This blood was used to infect mosquitoes with filarial parasites by means of a membrane feeding system. Brugia malayi, Wuchereria bancrofti and Dirofilaria immitis have been successfully transported in this way.

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Repeated infection of cats with Brugia pahangi: parasitological observations

Parasitology ◽

10.1017/s0031182000063666 ◽

1992 ◽

Vol 104 (3) ◽

pp. 415-420 ◽

Cited By ~ 13

Author(s):

D. A. Denham ◽

F. Medeiros ◽

C. Baldwin ◽

H. Kumar ◽

I. C. T. Midwinter ◽

...

Keyword(s):

Wuchereria Bancrofti ◽

Group Iv ◽

First Year ◽

Brugia Pahangi ◽

Group V ◽

Group Iii ◽

Group I ◽

Large Numbers ◽

Group Ii ◽

Short Time

Cats were repeatedly inoculated with infective larvae of Brugia pahangi. On parasitological grounds they could be divided into 5 groups. Group I – most cats (some 70%) became microfilaraemic (mf+) and retained high levels of microfilariae (mf) in their blood for over 2 years. In some Group I cats mf counts stabilized at high levels whilst in others mf counts continued to increase. Large numbers of fecund adult worms were recovered from their lymphatics. Adult counts were not made on the cats in the current experiments but over 100 adults have been recovered from ‘super-susceptible’ cats. Large amounts of B. pahangi adult antigen were consistently present in the serum of all Group I cats. About 30% of cats became amicrofilaraemic (mf–). In these cats the peak mf levels were seldom above 10000 mf/ml. Group II – these cats had less than 10 000 mf/ml and low antigen levels. After more than 1 year of being repeatedly infected B. pahangi adult antigen slowly declined and eventually could no longer be detected in their serum and the number of mf declined very slowly after the fall in antigen levels. This shows that in Group II cats the adult worms die and as the cats are resistant to the development of the continuing weekly inoculation of L3 no new adults can develop. Group III – these cats became mf – during the first year of infection but remained B. pahangi antigen-positive for many weeks after this and, at autopsy, had living adults in their lymphatics. Group IV – in these cats there was a sudden decline in the number of mf, usually in the first year and after they have received a relatively small number of re-infections. Circulating adult B. pahangi antigen disappeared from the serum within a short time of the loss of mf and at autopsy no adult female worms were found. Group V – these cats do not become mf+ when infected. These groups are compared to the parasitological groups seen in areas endemic for infection with Wuchereria bancrofti.

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