Overview of Onchocerciasis infection in Nigeria: The way forward Anidi MaryStella, MPH Student Walden University PH6165-4 Environmental Health Instructor:

Overview of Onchocerciasis infection in Nigeria: The way

forward

Anidi MaryStella, MPH Student Walden University

PH6165-4 Environmental HealthInstructor: Dr. Raymond Thron

4TH Term, 2009

Objectives• At the end of this presentation, we would have:At the end of this presentation, we would have:

– Increased understanding of onchocerciaisis.

– Increased understanding of the devastating impact of onchocerciasis on rural dwellers in Nigeria.

– Increase our knowledge about best practices and translate such practices into a national strategy for effective prevention and control measures.

– Increase our knowledge about sustainable strategies for controlling the diseases.

Onchocerciasis

• Also known as river blindness• A chronic disease caused by a filarial

nematode Onchocerca volvolus• O. volvolus is transmitted to humans by blood-

sucking blackflies- Simulium damnosum. • O. volvolus infests the eyes and epidermal

tissues of humans with microfilaria.

Alonso, L., Murdoch, M., Jefre-Bonet. (2009). Psycho-social economic evaluation of onchocerciasis: a literature review. Social medicine. 4(1)8-31.

Overview of onchocerciasis• Blackflies- Simulium damnosum breed only in

well oxygenated river especially fast flowing rivers.

• The larvae requires aquatic life to complete its life cycle.

• Infective larvae gains entrance to humans via exposed wounded skin.

• Larvae moves to subcutaneous tissues where they become encapsulated and form nodules.

World Health Organization. (2009). Onchocerciasis. Retrieved from http://www.who.int/topics/onchocerciasis/en/

Overview of onchocerciasis contd.

• The microfilariae found in the infected humans fluid and blood are transferred to the fly during blood meal.

• The larvae immobilizes the hosts cellular immune response.

• The host immune response to the dead microfilariae results in the formation of nodules.

Onwujekwe, O., Shi, E., Nwagbo, D., Akpala, C., Okonkwo, P. (1998). Willingness to pay for community-based ivermectin distribution: A study of three onchocerciasis-endemic communities in Nigeria. Tropical Medicine and International Health. 3(10):802-808.

Overview – life cycle

Center for Disease Prevention and Control. (2009). Onchocerciasis. Retrieved from http://www.dpd.cdc.gov/dpdx/hTML/ImageLibrary/A-F/Filariasis/body_Filariasis_il20.htm

Epidemiology• According to WHO, (2009) ‘Onchocerciasis is the

world’s second leading infectious cause of blindness’ (WHO, 2009).

• An estimate of 18 million people are infected with Onchocerciasis (Alonso et al, 2009).

• 99% of infected persons live in Africa (Alonso et al, 2009).

Reference1. Alonso, L., Murdoch, M., Jefre-Bonet. (2009). Psycho-social economic evaluation of onchocerciasis: a literature review. Social medicine. 4(1)8-31.

2. Special Programme for Research & Training in Tropical Diseases (TDR). (2009). Onchocerciasis. Retrieved from http://www.who.int/tdr/svc/diseases/onchocerciasis

Epidemiology• Globally, 270,000 preventable blindness

resulted in this infection (Alonso et al, 2009).• Globally, 500, 000 people are visually impaired

as a result of this infection (Alonso et al, 2009).

• About 40, 000 people become blind annually because of this infection (Alonso et al, 2009).

Alonso, L., Murdoch, M., Jefre-Bonet. (2009). Psycho-social economic evaluation of onchocerciasis: a literature review. Social medicine. 4(1)8-31.

Epidemiology contd.• Globally, an estimate of 80 million are at risk

(Abanobi, O., Anosike, J., 2000).• Approximately 40 million persons are at risk in

Nigeria (Abanobi, O., Anosike, J., 2000).• Current estimates indicates that 7 million

Nigerians are infected (Abanobi, et al., 2000).• > 120,000 Nigerians are suffering from

onchocerciasis related blindness.Abanobi, O., Anosike, J. (2000). Control of onchocerciasis in Nzerem-Ikem, Nigeria: baseline prevalence and mass distribution of ivermectin. Public Health. 114: 402-406

The figures in Nigeria

• > 1,000,000 adults Nigerians are blind • An estimate of 3,000,000 are visually impaired• Number targeted for therapeutic

onchocerciasis treatment 29, 509, 353 (WHO, 2009).

ReferenceSight saver. (2009). Important new data about blindness in Nigeria. Retrieved from http://www.sightsavers.org/our_work/around_the_world/west_africa/nigeria/9858.html

World Health Organization. (2009). Nigeria. Retrieved from http://www.who.int/apoc/countries/nga/en/

Stratification of national endemicity

• Mesoendemic zones are the savannah zones of the country.– Within the mesoendemic zones some areas have

high disease burden.

• Hyperednemicity zone for Onchocerciasis is within the rain forest zone of the country.– Some areas within this zone have low disease

burden.

Abanobi, O., Anosike, J. (2000). Control of onchocerciasis in Nzerem-Ikem, Nigeria: baseline prevalence and mass distribution of ivermectin. Public Health. 114: 402-406

Climatic map of Nigeria

Climate Map of Nigeria

Climate of map. (2009). Retrieved from http://www.onlinenigeria.com/maps/climateMap.asp

Trend of infection in Nigeria

• The concentration of the infection is highest in rural agricultural communities.

• Rural dwellers flee from this plaque and migrate to urban cities disrupting the socioeconomic development in their communities.

Reference1 Alonso, L., Murdoch, M., Jefre-Bonet. (2009). Psycho-social economic evaluation of onchocerciasis: a literature review. Social medicine. 4(1)8-31.

2. Abanobi, O., Anosike, J. (2000). Control of onchocerciasis in Nzerem-Ikem, Nigeria: baseline prevalence and mass distribution of ivermectin. Public Health. 114: 402-406

Implication of onchocerciasis infection

• Health– Infects multiple organs. Presence of other co-

infections like malaria, typhoid, and other tropical diseases can be debilitating .

– Psychosocial imbalance.– Psychological trauma– Big burden on the national health system.

• Socioeconomic consequences– Increases the national poverty level.

Impact of onchocerciasis on rural dwellers• Underdevelopment.• Social marginalization.• Sociocultural stigmatization.• Settlement.• Increased mortality of affected people due to negligence and

lack of proper medical care.• Lack of resourceful individuals to advocate for the cause of

the community.• Economic loss

Reference1 Alonso, L., Murdoch, M., Jefre-Bonet. (2009). Psycho-social economic evaluation of onchocerciasis: a literature review. Social medicine. 4(1)8-31.

2. Abanobi, O., Anosike, J. (2000). Control of onchocerciasis in Nzerem-Ikem, Nigeria: baseline prevalence and mass distribution of ivermectin. Public Health. 114: 402-406

Impact on onchocerciasis on the economy

• The socioeconomic development of fertile lands zones is low thereby affecting the productive of cash crops.

• Gross National Productivity is low.• The cumulative average of the national GDP will be

less than $2 (US dollar).• The poor communities will solely depend on the

average and rich communities for their livelihood and sustenance.

Onwujekwe, O., Shu, E., Nwagbo, D., Akpala, O., Okonkwo, P., (1998). Willingness to pay for community-based ivermectin distribution: A study of three onchocerciasis-endemic communities in Nigeria. Tropical Medicine and International Health 3(10):802- 808

Impact of onchocerciasis on the health system

• The rural health and medical system is in dire need of help.

• The most affected communities are medically underserved.

• They presence of co-infection rapidly depletes the limited allocated funds for treating other related illness.

• This constitutes huge burden of the health system- burden includes cost of treatment, care, and support.

• Healthcare providers are easily overwhelmed by this infection leading to huge gaps in service delivery.

Evidence based practice• Village-level education sessions has been proven to be the best

practice in addressing tropical diseases because of the following:– It empowers villagers with information about disease trend and

transmission.– It reduces the psychosocial stress and stigma associated with

infection.– It enables villagers to be actively involved in prevention measures

thereby minimizing the burden of the disease.

This is important because donor funds allocated for prevention is limited and has no therapeutic funds that will enable people to address the psychological and social effect of infection.

Evidence based practice

• The prophylactic distribution and administration of ivermectin to villagers and communities in endemic areas is one evidence that reduces the burden of the disease.

• Treatment adherence is evidentially achievable through proper village-level education.

Shu, E., Onwujekwe, O., Lokili, P., Okonkwo, P., (2000). A health club for a community school in south-eastern Nigeria: influence on adult perception of onchocerciasis and compliance with community-based ivermectin therapy. Tropical Medicine and International Health . 5(3):222-226.

Evidence based practice

• The use of community-directed treatment with ivermectin (CDTI) adopted to eliminated onchocerciasis as a disease of public health importance in tropical regions have been proven to treat millions of people and avert blindness.

• Evidentially effective use CDTI will be the only profitable approach to eliminate onchocerciasis in Nigeria.

Adeboye, G., Akinsanya, B., Otubanjo, A., Ibidapo, C., Atalabi, T., Okwuzu, J., Adejai, E., Braide, E. (2008). Prevalence of loiasis in Ondo State, Nigeria, as evaluated by the rapid assessment procedure for loiasis (RAPLOA). Annal sof Tropical Medicine and Parasitology. 102(3):215-227.

Evidence based practice

• Effective interruption of transmission of the parasite requires intermittent repeated treatment for many years with the dose of ivermectin rather than an annual dose.

Emukah, G., Enyinnanya, U., Olaniran, N., Akpan, E., Hopkins, D., Miri, E., Amazigo, U., Okoronkwo, C., Stanley, A., Rakers, L., Richards, F., Katabarwa, M. (2008Factors affecting the attrition of community-directed distributors of ivermectin, in an onchocerciasis-control programme in the Imo and Abia states of south-eastern Nigeria. Annals of Tropical Medicine and Parasitology. 102(1):45-51.

National treatment coverage

World Health Organization. (2009). Rapid epidemiological mapping of onchocerciasis in Nigeria. Retrieved from http://www.who.int/apoc/countries/ng_web.jpg

Significance of onchocerciasis infection

• The national treatment coverage indicates that most areas are not covered.

• In 2003 it was reported that ivermectin coverage reached its national peak of 70%.

• This rapidly declined in 2004 to 60.7%.• This rapid decline is significantly high and indicates that

coverage needs to be sustained

Adeboye, G., Akinsanya, B., Otubanjo, A., Ibidapo, C., Atalabi, T., Okwuzu, J., Adejai, E., Braide, E. (2008). Prevelance of loiasis in Ondo State, Nigeria, as evaluated by the rapid assessment procedure for loiasis (RAPLOA). Annal of Tropical Medicine and Parasitology. 102(3):215-227.

Significance of onchocerciasis infection

• The national treatment coverage indicates that most areas are not covered.

• This is significantly important because it gives an insight of the estimated cost required to cover such areas.

• It also indicates the urgency required in reaching the uncovered areas to avoid spread and treatment relapse/resistance.

• This most importantly signifies that government needs to act immediately.

Sustainability of CDTI: the way forward

• The government can provide incentives for communities and CDTI to sustain the activity.

• Incentives helps heals and compensates burn out.• Structure a formal channel of supervision for the

CDTI and support from the health system.• Impact the CDTIs with skills in other public health

areas .• This community development approach will

empower them to be useful resources in addressing other tropical diseases.

Sustainability of CDTI: the way forward

• Empowering the CDTI with a multitiered approach to address other tropical co-infections.

Food for thought

• Collaboratively we can work together to sustain the CDTI initiative.

• The amalgamation of all approaches and our efforts will lead to the elimination of onchocerciasis as a disease of public health importance in Nigeria

Conclusion

• We can make a difference in Nigeria.• Nigeria can be recreated to become a safe

haven for the future generation.• Lets work together to make this happen

Questions

Reference• Abanobi, O., Anosike, J. (2000). Control of onchocerciasis in

Nzerem-Ikem, Nigeria: baseline prevalence and mass distribution of ivermectin. Public Health. 114: 402-406.

• Adeboye, G., Akinsanya, B., Otubanjo, A., Ibidapo, C., Atalabi, T., Okwuzu, J., Adejai, E., Braide, E. (2008). Prevelance of loiasis in Ondo State, Nigeria, as evaluated by the rapid assessment procedure for loiasis (RAPLOA). Annals of Tropical Medicine and Parasitology. 102(3):215-227.

• Alonso, L., Murdoch, M., Jefre-Bonet. (2009). Psycho-social economic evaluation of onchocerciasis: a literature review. Social medicine. 4(1)8-31.

Reference• Emukah, G., Enyinnanya, U., Olaniran, N., Akpan, E., Hopkins, D.,

Miri, E., Amazigo, U., Okoronkwo, C., Stanley, A., Rakers, L., Richards, F., Katabarwa, M. (2008Factors affecting the attrition of community-directed distributors of ivermectin, in an onchocerciasis-control programme in the Imo and Abia states of south-eastern Nigeria. Annals of Tropical Medicine and Parasitology. 102(1):45-51.

• Center for Disease Prevention and Control. (2009). Onchocerciasis. Retrieved from

http://www.dpd.cdc.gov/dpdx/hTML/ImageLibrary/A-F/Filariasis/body_Filariasis_il20.htm

.

Reference• Onwujekwe, O., Shu E., Nwagbo, D., Akpala, C., Okonkwo,

P. (1998). Willingness to pay for community-based ivermectin distribution: A study of three onchocerciasis-endemic communities in Nigeria. Tropical Medicine and International Health. 3(10):802-808

• Shu, E., Onwujekwe, O., Lokili, P., Okonkwo, P., (2000). A health club for a community school in south-eastern Nigeria: influence on adult perception of onchocerciasis and compliance with community-based ivermectin therapy. Tropical Medicine and International Health . 5(3):222-226.

Reference

• Special Programme for Research & Training in Tropical Diseases (TDR). (2009). Onchocerciasis. Retrieved from http://www.who.int/tdr/svc/diseases/onchocerciasis.

• World Health Organization. (2009). Onchocerciasis. Retrieved from http://www.who.int/topics/onchocerciasis/en/

• World Health Organization. (2009). Rapid epidemiological mapping of onchocerciasis in Nigeria. Retrieved from http://www.who.int/apoc/countries/ng_web.jpg