Care of Onchocercal Skin Disease
--------------------------------
Source: tdr-scientists@who.ch
This is an other article from the new TDR Newsletter - Issue 55.
Best regards,
Jocelyne Bruyere,
TDR Communications
mailto:bruyerej@who.ch
--
New Light Shed on the Importance and Care of Onchocercal Skin Disease
Onchocercal skin disease and itching has, until fairly recently, been
given little attention. But following the demonstration of its public
health and social importance in 1994 (document TDR/AFR/RP/95.1), the
Task Force on Onchocerciasis Operational Research (now superseded by
the Task Force on Community Directed Treatment of Lymphatic Filariasis
and Onchocerciasis) was requested to try and assess its economic im-
pact. A multicountry study was consequently undertaken in Ethiopia, Su-
dan and Nigeria, with the aim of determining the effect of onchocercal
skin disease on labour input and the effect of severe reactive skin
disease in the household on school attendance by children. This study
has now been completed and the results were analysed during a recent
workshop in Accra, Ghana.
One of the most remarkable findings of the study concerned the rela-
tionship between school attendance of a child and skin disease status
of the head-of-household. Where the head-of-household had onchocercal
skin disease (OSD), children were twice as likely to drop out of school
compared to other children of the same age from the same community. The
relationship was especially strong among girls, who were 2.6 times as
likely to drop out of school if the head-of-household had OSD than if
the head-of household did not have OSD. Given that OSD is very preva-
lent in endemic areas, it can be concluded that onchocerciasis is also
an important obstacle to educational development.
With regard to direct costs, it was found that people with OSD spend
US$ 20 more each year on health-related expenditures than do people
without OSD. This represents some 15% of their annual income. And fur-
thermore, there are substantial `time costs' too. Those with severe OSD
were found to make significantly more visits to health care facilities
and to spend more time seeking health care than those without severe
OSD. People with severe OSD therefore spend significantly less time on
productive activities than do people without OSD.
Another study was aimed at determining the effect of ivermectin treat-
ment on onchocercal skin disease. This entailed carrying out a double-
blind, placebo-controlled trial of the effect of three-monthly, six-
monthly and annual ivermectin treatment on perceived and observed on-
chocercal skin disease and itching. Four sites were involved in the
trial (Uganda, Ghana and two sites in Nigeria) and the field work was
completed in February 1997.
The results were analysed during a workshop held in April. A decline of
40-50% in the prevalence of severe itching after ivermectin treatment
as compared to placebo, sustained for up to 12 months after the first
treatment, was apparent. The effect was similar for three-monthly, six-
monthly and annual ivermectin treatment. There was also a statistically
significant decline in the prevalence of reactive skin lesions follow-
ing ivermectin treatment as compared to placebo, mainly a decline in
early-stage skin lesions; there was no significant difference between
the various ivermectin treatment regimens in this respect. An in-depth,
blinded analysis of serial skin photographs taken during the trial,
which is yet to be completed, will provide further information about
the effect of ivermectin treatment on skin lesions.
Because of the demonstrated immediate effect of ivermectin treatment,
in addition to the long-term preventive effect of repeated treatment,
the researchers strongly recommended that the use of ivermectin for the
control of onchocercal skin disease be intensified.
--
Send mail for the `AFRO-NETS' conference to `afro-nets@usa.healthnet.org'.
Mail administrative requests to `majordomo@usa.healthnet.org'.
For additional assistance, send mail to: `owner-afro-nets@usa.healthnet.org'.