The History of Bancroftian Lymphatic Filariasis in Australasia and Oceania: Is There a Threat of Re-Occurrence in Mainland Australia?

Abstract

Lymphatic filariasis (LF) infects an estimated 120 million people worldwide, with a further 856 million considered at risk of infection and requiring preventative chemotherapy. The majority of LF infections are caused by Wuchereria bancrofti, named in honour of the Australian physician Joseph Bancroft, with the remainder due to Brugia malayi and B. timori. Infection with LF through the bite of an infected mosquito, can lead to the development of the condition known as elephantiasis, where swelling due to oedema leads to loss of function in the affected area and thickening of the skin, ‘like an elephant’. LF has previously been endemic in Australia, although currently, no autochthonous cases occur there. Human immigration to Australia from LF-endemic countries, including those close to Australia, and the presence of susceptible mosquitoes that can act as suitable vectors, heighten the possibility of the reintroduction of LF into this country. In this review, we examine the history of LF in Australia and Oceania and weigh up the potential risk of its re-occurrence on mainland Australia.

Lymphatic Filariasis: An Overview

“…In Tokyo, Yushitaro Matsuura found a female adult worm in an inguinal lymph node (1896). Later, a lot of work was done in defining various manifestations of filariasis and the aim of current researches is concentrated on prevalence, treatment, transmission cycles, and newly discovered species [6][7][8][9][10].…”

“…After mating, the females produce numerous microfilariae, which migrate into the lymphatic system and spread through the bloodstream (Fig. 5) [7,8,14,18,[23][24][25].…”

“…7), and limbs and hydrocele swelling (scrotal swelling or breast swelling) ( Fig. 8) and may develop to filarial abscesses [5,8,25,[28][29][30].…”

“…• Blood tests: Blood counts are done, especially the eosinophils, in to the characteristics of the stage larva (L3) in human, such as the number and position of caudal nuclei, cephalic space, and the presence or absence of sheath (Fig. 9) [5,[7][8][9]15,24,35,36]. • Identification of microfilariae in a urine and hydrocele fluid: This is done by centrifuging the fluids samples, the resulting deposits are put on a slide, and examined under the microscope [7,9,30].…”

Prediction pipeline for discovery of regulatory motifs associated with Brugia malayi molting

“…Brugia malayi is a mosquito-borne filarial nematode and one of the causative agents of lymphatic filariasis, commonly known as elephantiasis. Currently, 856 million people in 52 countries require preventative chemotherapy to stop the spread of the disease (Gordon et al 2018). Transmission occurs when the mosquito vector introduces infective third-stage larvae (L3) during their blood meal.…”