Adverse reactions from community directed treatment with ivermectin (CDTI ) for onchocerciasis and loiasis in Ondo State, Nigeria

Onchocerciasis is an endemic disease in Ondo state, Nigeria. Community directed distribution of ivermectin is currently on-going in some local government areas of the state. Randomly selected persons (2 331 males and 2 469 females) were interviewed using a modified rapid assessment procedure for Loa loa (RAPLOA) to assess community directed treatment with ivermectin. The retrospective study evaluated the coverage, impacts and adverse reactions to the drug treatment. A questionnaire was administered by house-to-house visit in six local government areas, implementing community directed treatment with ivermectin (CDTI) in this bioclimatic zone. A total of 2,398 respondents were reported to have participated in the treatment. The overall ivermectin coverage of 49.96% was recorded (range 0 - 52% in different communities). Adverse reactions from ivermectin administration were experienced in 38% of individuals. Diverse adverse reactions experienced included predominantly itching (18.50%); oedema, especially of the face and the limbs (8.2%); rashes (3.4%) and body weakness (2.4%). Expulsion of intestinal worms occurred in 0.96% of the respondents. The occurrence of adverse reactions in relation to age categories was statistically significant. Neither fatal nor severe adverse reactions were reported by respondents. Significantly, despite experienced adverse reactions, continued participation, acceptability and compliance to ivermectin treatment was expressed by the various communities. This attitude is in consonance with the African Programme for Onchocerciasis Control (APOC) objectives. Rev. Biol. Trop. 56 (4): 1635-1643. Epub 2008 December 12.

La oncocercosis es endémica en el estado Ondo, Nigeria. Se seleccionaron 4 800 personas al azar para evaluar con encuesta retrospectiva la cobertura, efectos y reacciones al tratamiento farmacológico con ivermectina administrado por la misma comunidad. La cobertura global de ivermectina fue 50 % con reacciones adversas en 38 % de los individuos. Estas fueron comezón picazón (18%), edema, especialmente de la cara y las extremidades (8%), erupciones cutáneas (3%) y debilidad (2%); dependieron de la edad y no hubo reacciones más graves. La expulsión de las lombrices intestinales se produjo en 96% de los encuestados. A pesar de las reacciones adversas, hubo continuidad, aceptación y cumplimiento del tratamiento con ivermectina, en consonancia con los objetivos del Programa Africano para el Control de Oncocercosis (APOC).

Prevalences of loiasis in Ondo state, Nigeria, as evaluated by the rapid assessment procedure for loiasis (RAPLOA).

The rapid assessment procedure for loiasis (RAPLOA) was used to assess the prevalences of loiasis among 4800 subjects in 60 villages in Ondo state, south-western Nigeria. Coverages for community-directed treatment with ivermectin (CDTI) were assessed in the same communities, which were located in the Owo, Akure North, Ifedore, Akure South, Ondo East and Ondo West local government areas (LGA). In addition, fingerprick blood samples were collected from 80 individuals in each of six villages (i.e. one village in each LGA investigated) and checked for Loa loa microfilaraemia. Microfilaraemias were only detected in three of the villages where blood samples were collected and then only at low prevalences (1.25%-5.0%) and intensities (267-1600 microfilariae/ml). No serious adverse events were or ever had been related to the CDTI but mild or moderate adverse reactions were quite common, especially in Akure North (55.0%) and Owo (40.2%). A female subject was more likely to report an history of eye worm than a male subject (20.3%-35.7% v. 20.8%-26.5%, according to LGA). Although the subjects aged 41-50 years formed the age-group most likely to report an history of eye worm (32.7%), the highest CDTI coverage was recorded in the subjects aged 61-70 years (54.7%). The results indicated that CDTI had helped to reduce the prevalence and intensity of Loa microfilaraemia and that ivermectin can continue to be used for mass administrations in Ondo state with little risk of serious adverse events.

Adverse reactions from community directed treatment with ivermectin (CDTI) for onchocerciasis and loiasis in Ondo State, Nigeria.

Onchocerciasis is an endemic disease in Ondo state, Nigeria. Community directed distribution of ivermectin is currently on-going in some local government areas of the state. Randomly selected persons (2331 males and 2469 females) were interviewed using a modified rapid assessment procedure for Loa loa (RAPLOA) to assess community directed treatment with ivermectin. The retrospective study evaluated the coverage, impacts and adverse reactions to the drug treatment. A questionnaire was administered by house-to-house visit in six local government areas, implementing community directed treatment with ivermectin (CDTI) in this bioclimatic zone. A total of 2,398 respondents were reported to have participated in the treatment. The overall ivermectin coverage of 49.96% was recorded (range 0-52% in different communities). Adverse reactions from ivermectin administration were experienced in 38% of individuals. Diverse adverse reactions experienced included predominantly itching (18.50%); oedema, especially of the face and the limbs (8.2%); rashes (3.4%) and body weakness (2.4%). Expulsion of intestinal worms occurred in 0.96% of the respondents. The occurrence of adverse reactions in relation to age categories was statistically significant. Neither fatal nor severe adverse reactions were reported by respondents. Significantly, despite experienced adverse reactions, continued participation, acceptability and compliance to ivermectin treatment was expressed by the various communities. This attitude is in consonance with the African Programme for Onchocerciasis Control (APOC) objectives. Rev. Biol.

Market survey of loiasis: prevalence and adverse reactions to ivermectin using a rapid procedure for loiasis.

OBJECTIVES: 1. To assess the levels of endemicity of loiasis in a total of 30 selected villages covering an area of 5.2 sq km in Owo, Akure North, Akure South, Ondo East, Ondo West and Ifedore local governments in Ondo State, Nigeria, using Rapid Assessment for loiasis technique. 2. To obtain information on adverse reactions which occurred during previous administrations of the drug ivermectin used for the treatment of loiasis and onchocerciasis in the study area. METHODS: Consent was obtained from the chairman of each local government village head and individuals were co-opted into the study. A total of 480 individuals were interviewed, 80 from each of the six local governments, during the regular scheduled community market days. Survey for Loa loa was carried out according to specifications in "Guidelines for rapid Assessment of Loa loa (TDR, 2002). RESULTS: Among the 480 respondents, 80 (16.7%) reported having had a history of loiasis while 11 (2.3%) had recent occurrence of the disease. The local name given to the disease in all the villages studied is "aran oju". Respondents in Ondo East local government had an eyeworm history of 23 (28.8%) and occurrence of loiasis was 02 (2.5%), these were the highest figures recorded. Using the SPSS version 10 package for data analysis, demographic factors of age and gender were not significant determinants of prevalence (> 0.05). Ondo East and Ifedore local governments had significant levels of loiasis prevalence (p < 0.05). Adverse reactions from the retrospective ivermectin administration was 04 (0.83%). This was statistically insignificant (p > 0.05). CONCLUSION: Market surveys in rural communities were considered to be cost effective and rapid in the determination of prevalence of any disease. Since less than 40% of the respondents in the study area reported having had a history of eyeworm, the entire area was classified as "low risk" as regards the administration of ivermectin.

Behaviour and population dynamics of the major anopheline vectors in a malaria endemic area in southern Nigeria.

BACKGROUND & OBJECTIVES: Anopheline mosquitoes consist of a large number of species each of which differs from another in population, resting and feeding behaviour in relation to the prevailing conditions in the locality. A longitudinal study was carried out to investigate the population dynamics, resting and feeding behaviour of the major anopheline species found in a rain forest zone of Nigeria. METHODS: Mosquitoes resting and biting indoors were collected using WHO standard techniques and supplemented with outdoor-biting collections in the study areas between January and December 2004. Samples were sorted and identified microscopically for morphological features while molecular identification was carried out using polymerase chain reaction (PCR) techniques. RESULTS: PCR-based tests showed that both indoor and outdoor collections constitute three groups of Anopheles mosquitoes, An. gambiae s.l. Giles (68.6%), An. funestus Giles (30.7%) and An. moucheti Evans (0.7%). Of the 1342 female Anopheles mosquitoes collected indoors, 799 were caught resting and 543 were caught biting. The outdoor-biting population accounted for 28.8% of the total collections (n=1885). There was no significant difference (p > 0.05) in the biting activities (indoors and outdoors) of these species in four villages. However, An. arabiensis and An. moucheti were more exophagic with >60% of their biting occurring outdoors while An. gambiae and An. funestus were more endophagic with >55% of their biting occurring indoors. The human-vector contact with An. gambiae and An. funestus (indoors) was about 73.3 and 66.7%, respectively as against 27.7% in An. arabiensis and 25.3% in An. moucheti. This gave the corresponding man-biting rates (MBR) of 17.5 bites/man/night for An. gambiae, 14.6 bites/man/night for An. funestus, 6.7 bites/man/night for An. arabiensis and 4.3 bites/man/night for An. moucheti. Moreover, the number of An. gambiae and An. funestus caught resting indoors was significantly higher than the other two species (p < 0.05). The wet season collections showed thatAn. gambiae caught were more than 67% of the total catch while An. arabiensis was predominant in the dry season (chi2 = 75.44, df = 3, p < 0.01). INTERPRETATION & CONCLUSION: The present study highlights some aspects of the behaviour of anopheline mosquitoes in southern Nigeria which is an important component of epidemiological study of malaria. This information provides basis to the understanding of the role played by the identified anopheline species in malaria transmission and a baseline to formulate malaria control programme.