Rapid assessment method for prevalence and intensity of Loa loa infection.
OBJECTIVE
To assess the validity of observations on eye worm and Calabar swellings for the rapid assessment of the prevalence and intensity of loiasis at the community level.


METHODS
A total of 12895 individuals over the age of 15 years living in 102 communities in Cameroon and Nigeria took part in the study. A standardized questionnaire was administered to participants from whom finger-prick blood samples were collected and examined for Loa loa microfilariae. Rapid assessments of the prevalence and intensity of loiasis were made on the basis of a history of eye worm or Calabar swellings.


RESULTS
There was a strong correlation between the indices of the rapid assessment procedures and the parasitological indices of L. loa endemicity. The rapid assessment indices were effective in diagnosing high-risk communities (sensitivity 94-100%; specificity 66-92%). The highest sensitivity (100%) and specificity (92%) were obtained with a rapid assessment procedure based on a history of eye worm lasting 1-7 days together with confirmation by the guided recognition of a photograph of adult L. loa in the eye.


CONCLUSIONS
Rapid assessment of the prevalence and intensity of loiasis at the community level can be achieved using a procedure based on the history of eye worm lasting 1-7 days together with confirmation by the guided recognition of a photograph of an adult L. loa in the eye.
Takougang
Innocent
I
Department of Public Health, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, Cameroon. itakoug@hotmail.com
Meremikwu
Martin
M
Wandji
Samuel
S
Yenshu
Emmanuel V
EV
Aripko
Ben
B
Lamlenn
Samson B
SB
Eka
Braide L
BL
Enyong
Peter
P
Meli
Jean
J
Kale
Oladele
O
Remme
Jan H
JH
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002163:Cameroon / Q000453:epidemiology; D019353:Endemic Diseases; D005369:Filaricides / Q000009:adverse effects / Q000627:therapeutic use; D006801:Humans; D007559:Ivermectin / Q000009:adverse effects / Q000627:therapeutic use; D008117:Loa / Q000302:isolation & purification / Q000469:parasitology*; D008118:Loiasis / Q000097:blood* / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009549:Nigeria / Q000453:epidemiology; D019370:Observation; D017181:Onchocerca volvulus / Q000302:isolation & purification / Q000469:parasitology; D009855:Onchocerciasis / Q000097:blood* / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology; D011237:Predictive Value of Tests; D015995:Prevalence; D012307:Risk Factors; D011795:Surveys and Questionnaires
D005369:Filaricides; D007559:Ivermectin