Does lymphatic filariasis still occur in the Solomon Islands?

Monday, 19 January, 2015
Elephantiasis of right foot - Outer Shortland Islands

Solomon Islands was declared free of lymphatic filariasis (LF) by the World Health Organization in 2011. Elephantiasis is the disfiguring end stage disease of LF (image). However, ongoing surveillance is required to ensure that a country remains LF-free. A team from the Atoifi Health Research Group, in response to requests from residents, visited the Outer Shortland Islands last week to follow-up rumours of elephantiasis.

The team was led by Humpress Harrington (Atoifi Adventist Hospital) and included Dr David MacLaren (James Cook University), Eileen Otuona (a nurse from Atoifi Adventist Hospital and Outer Shortland islander) and me (Rick Speare).

How do you find LF? First, inform the community. We gave four presentations to raise awareness about LF. This allowed people with signs and symptoms or concerns to present for testing. Second, do a rapid card test that detects antigens of the causative worm, Wuchereria bancrofti (Wb). This test gives a result in 10 minutes and can be done at any time of the day. Third, if anyone has Wb antigen, test the blood for microfilaria after 10 PM. Finally, perform confirmatory tests in the JCU laboratory.

The end result of chasing rumours? We found one case of elephantiasis, but this person's worms were dead and they are not an infection risk. We found no evidence of current infection with W. bancrofti in 47 people. The Outher Shortland communities are now much better informed about LF and its transmission. Concepts of elephantiasis being due to witchcraft seem to have been adequately addressed.

The Atoifi team proposed an algorithm to investigate possible cases of LF in countries that have eliminated LF (Harringtom et al 2013). This approach seems to be feasible and effective. Our Outer Shortland Island survey was based on this.

This study was funded by a grant from the School of Medicine and Dentistry, JCU, underpined by a grant from TDR, the Special Programme for Research and Training in Tropical Diseases, cosponsored by United Nations Children’s Fund, United Nations Development Programme, the World Bank and WHO (grant 1–811001688),

Harrington H, Asugeni A, Jimuru C, Gwalaa J, Ribeyro E, Bradbury R, Joseph H, Melrose W, MacLaren D, Speare R. A practical strategy for responding to a case of lymphatic filariasis post-elimination in Pacific Islands. Parasites and Vectors 2013;6:218.

Posted by Rick Speare