Power point presentation on river blindness

River blindness

1. ONCHOCERCIASIS (River Blindness) BY DR. ONYEBI JOHN 23 rd August 2024

2. Introduction of Onchocerciasis (River Blindness) Onchocerciasis is a n eye and skin disease also a vector-borne disease caused by the filarial worm parasite Onchocerca volvulus. Transmitted by blackflies ( Simulum demnosum ) which breed in fertile fast flowing rivers. Also known as River Blindness due to its most extreme manifestation and the breeding site of the blackfly .

3. Host and Mode of Transmission Female blackflies bites an infected human host and sucks up larvae of O. volulus Larvae become infective as it develops within the blackfly Infects another human during blood meal Infective larvae migrate and form nodules as they mature Female worm reproduces generating ~1000 microfilariae per day Causes debilitating skin and eye lesions as they migrate and die

4. Mode of Transmission Source: River Blindness: A forgotten Disease, The Carter Center. Retrieved from http://www.cartercenter.org/news/documents/doc2217.html

5. Magnitude of Onchocerciasis Globally: - second leading cause of blindness - approximately 90 million are at risk of infection - 37 million are infected with the parasite - 500,000 are blind & 1.5 million visually impaired - endemic regions include Africa, Latin America and Yemen In Africa: - 99% of cases present in 27 sub-saharan African countries

6. Magnitude of Onchocerciasis ( Contd ) In Nigeria : - Majority are infected with onchocerciasis - 35, 014 hyper-endemic communities - Approximately 28 million individuals reside in these communities

7. Morbidity Patterns Skin inflammatory response to motile microfilaria causes itching and rashes. Debilitating and disfiguring skin conditions including skin, nodules, hanging groin, leopard skin, thinning of the skin and more. Severe cases impair vision and causes blindness.

8. Morbidity Patterns (contd.) Skin Nodules - appear when microfilariae forms clusters under the skin - as microfilariae die off, it causes itching within the upper layer of the skin Image Source: FiLARiA -EU Onchocerciasis Symptoms . Retrieved from http://www.filaria.eu/treat/treat/oncho/symptoms.html

9. Morbidity Patterns (contd.) Hanging groin - results when microfilariae invades the lymph nodes - destroys skin elasticity as worms migrate to the groin area - this causes loose & hanging folds -more common in men than women Image source: The Filarial Genome Network (2011). Onchocerca volvulus: The Causative Agent of River Blindness.

10. Morbidity Patterns ( contd ) Leopard skin - prominent in the lower limbs -intense itching - skin loses elasticity and pigmentation Image Source: APOC. Retrieved from http://www.who.int/apoc/onchocerciasis/disease/en/index.html

11. Ocular Implications Onchocerciasis also leads to Impairment of vision and blindness - occurs in severe cases when lesions develop in the eye - determined by microfilariae worm load near the eye Image Source: OCP: African Programme for Onchocerciasis Control. Retrieved from https://apps.who.int/ocp/slides/index.htm

12. Ocular Implications ( contd ) This lesions could lead to Corneal Opacifications (sclerosis, keratitis) Secondary angle closure glaucoma and Open angle glaucoma Cataracts Chorioretinitis Optic atrophy

13. Social Consequences of Onchocerciasis Disruption of family life and relationships - Desertion of from rural to urban parts - affects sexual life of affected couples Limited social interaction - Onset of symptoms reduces self-esteem, reputation - Stigmatization

14. Social Consequences of Onchocerciasis ( contd ) Impact on women and children - affects the age of marriage in young women - their choice of their partners - lessens bonding between new mother and child Educational impact on children - children drop out from school to lead blind family members Image Source: OCP: African Programme for Onchocerciasis Control. Retrieved from https://apps.who.int/ocp/slides/index.htm

15. Economic Consequences of Onchocerciasis Direct Costs - include health care costs of rehabilitation Indirect Costs - include costs stemming from the loss of productivity

16. Economic Consequences of Onchocerciasis Reduces work productivity - individuals afflicted with disabling skin conditions are unable to work - work activities in these communities include farming, fishing, handicraft, trading etc. Urban migration and slum development - unable to access and secure employment - experience extreme poverty and become beggars on the streets - settle in shanty towns and resort to living in slums

17. Control of Onchocerciasis : Strategies, Techniques and Challenges Vector Control: - ground application or aerial spraying of larvicide in breeding waters of the blackflies Limitations -expensive - concern of the effect of chemicals on the environment including vegetation, aquatic life and the air. Image Source: OCP: African Programme for Onchocerciasis Control. Retrirved from https://apps.who.int/ocp/slides/index.htm

18. Control of Onchocerciasis : Strategies, Techniques and Challenges (contd.) Ivermectin ( Mectizan ®) - Potent and cost- effective - one oral dose annually for 16 – 18 years - gradually destroys and inactivates microfilariae - suppresses reproduction of adult Image Source: WHO, (2011) Ivermectin . Retrieved from http://www.who.int/apoc/cdti/ivermectin/en/index.html

19. Control of Onchocerciasis : Strategies, Techniques and Challenges (contd.) Ivermectin benefits - effective against other intestinal parasites - relieves itching, improves skin texture and less ill health - increase physical vitality and performance

20. Status of Onchocerciasis Control in Nigeria Initial launch of community-directed treatment with ivermectin (CDTI) project was in 1997 As of 2007, 27 active CDTI projects present Only a single national onchocerciasis task force (NOTF)-secretariat supported projects No vector elimination projects

21. Status of Onchocerciasis Control in Nigeria ( contd ) Ivermectin distribution (as of 2007) - treatment target was 35 339, and so far 33 924 communities have been treated with ivermectin . - covering 96% of endemic communities in 2006 Therapeutic coverage (as of 2007) - treatment target was 29 509 353 people, so far 23 464 448 people have been treated with ivermectin - covering 79.5% of the infected population Training (as of 2007) - 91 278 are trained or retrained community-directed distributors - 323 people per community-directed distributor -22982 trained or retrained health workers

22. Profile of Onchocerciasis in Nigeria Image source: WHO, (2011) African Programme for Onchocerciasis Control (APOC). Retrieved from http://www.who.int/apoc/countries/ng_web.jpg

23. Role of International NGOs APOC and OCP by the WHO - Promote control strategies via aerial spraying and donation of Mectizan - Empowering communities in delivery of ivermectin in endemic regions - Work with the government and community leaders in educating and training health workers

24. Role of Nigerian Federal and State Governments Federal and State Government - Commit, allocate, and manage resources including financial and human resources - Form collaborations and partnerships with NGOs to achieve success - Educate and train health workers in the distribution of ivermectin - Inform local government and community leaders of goals and plans

25. Role of Local Government and Community Leaders Mobilize community members and health workers in the mass distribution of ivermectin Organize training workshops managed by NGOs and ministries of health Inform community members when ivermectin distribution will take place. Develop self-reliance and self-efficacy of implementing the program Ensure sustainability and local control of programs

26. Conclusion Successful control of Onchocerciasis possible due to: - the use of a comprehensive regional approach - community participation and empowerment -sustained long-term partnerships (Levine, 2006) More efforts needed: - sustainability of control programs - improvement in the county’s health care system

27. REFERENCES Abanobi , O.C., Anosike , J.C., Edungbola , L.D., (1993). Observation on the Deworming Effect of Mectizan on Gastro-intestinal Helminths during Onchocerciasis Mass Treatment in Imo State Nigeria. Nig. J. Parasitology 14, 11-16. Akogun , O. B., Akogun , M. K., Audu , Z., (2000). Community-Perceived Benefits of Ivermectin Treatment in North-Eastern Nigeria. Social Science & Medicine 50: 1451-1456 CDC, (2011) Parasites – Onchocerciasis . Retrieved from http://www.cdc.gov/parasites/onchocerciasis/epi.html Levine, R., (2007). Case Studies in Global Health: Millions Saved. Sudbury, MA: Jones and Bartlett Opara , K. N., Fagbemi O. B., Ekwe , A., Okenu D.M.N., (2005). Status of Forest nchocerciasis in the Lower Cross River Basin, Nigeria: Entomologic Profile after Five Years of Ivermectin Intervention. Am. J. Trop. Med. Hyg ., 73(2), 371–37. Ubachukwu , P. O., (2006). Socio-Economic Impact Of Onchocerciasis With Particular Reference To Females And Children: A Review. Animal Research International; 3(2)

28. REFERENCES ( contd ) Ubachukwu , P. O., (2006). Socio-Economic Impact Of Onchocerciasis With Particular Reference To Females And Children: A Review. Animal Research International; 3(2), 494-504 WHO, (2011). Onchocerciasis Control Programme in West Africa (OCP). Retrieved from http://www.who.int/apoc/onchocerciasis/ocp/en/index.html WHO, (2011a). Afican Programme for Onchocerciasis Control (APOC) Nigeria: Onchocerciasis status. Retrieved from http://www.who.int/apoc/countries/nga/en/index.html WHO, (2011b). APOC: Life Cycle of Onchocerca volvulus. Retrieved from http://www.who.int/apoc/onchocerciasis/lifecycle/en/index.html WHO, (2011c). APOC: Ivermectin . Retrieved from http://www.who.int/apoc/cdti/ivermectin/en/