Onchocerciasis, also known as river blindness, is a neglected tropical disease caused by the parasitic worm Onchocerca volvulus (1). The larvae of the worm called microfilariae are transmitted by bites of infected blackflies (genus Simulium) which breed in highly oxygenated bodies of water, such as fast flowing rivers and streams (2). Clinical indicators/symptoms of onchocerciasis include nodules on the skin containing the adult worms, intense itching and rashes that can lead to leopard skin, and scaring of the eyes leading to blindness caused by the larval microfilaria. These symptoms take 2–3 years to manifest themselves depending on the individual. Although these symptoms are not life-threatening, they can cause long term chronic pain and disability in affected people (3).

The World Health Organization (WHO) approximates that 25 million people are infected with onchocerciasis worldwide, 90% of whom reside in sub-Saharan Africa (4). More specifically, onchocerciasis remains a significant public health crisis in Ghana as the country has the highest endemicity in western Africa (5). Agriculture is the second largest employment sector in Ghana, with 38.3% of residents supporting their livelihoods through agriculture (6). Rural agricultural communities in southern Ghana are close to rivers that are known to be active breeding grounds for blackflies and for onchocerciasis disease transmission (7).

Vector control activities conducted by the Onchocerciasis Control Program (OCP) from 1974 to 2002, along with treatment using ivermectin beginning in 1997 have diminished the transmission of onchocerciasis in Ghana (7). However, while these strategies significantly reduced the number of cases of the disease, transmission of onchocerciasis by blackflies remains a public health concern within endemic areas. Despite the introduction of community-directed treatment with ivermectin (CDTI), inadequate funding and ineffective management have resulted in uneven distribution of the drug, lowering the effectiveness of the treatment and limiting ivermectin coverage in endemic communities (7). Additionally, lack of community awareness regarding the availability and benefits of mass drug administration (MDA), has hindered community participation. Oftentimes, mass distribution of ivermectin would take place during workdays when community members were working on their farms and unable to participate (8).

Studies conducted on knowledge, attitude and prevention practices regarding onchocerciasis in endemic areas of countries in Africa have shown that although approximately 50-57% of respondents had adequate knowledge of onchocerciasis (9–11), the majority of residents lacked accurate knowledge of the causative agent, the vector, transmission, and symptoms of the disease (10–13). Accurate knowledge of these key features of the disease, and proper understanding of the disease risk, and the ensuing disability are important for residents to implement and sustain practices that decrease disease transmission and burden. In these reported studies, appropriate attitude ranged from 9-42% of participants and good prevention practices ranged from 14-47% (9–11). Regarding factors associated with onchocerciasis prevention practices, one study found that participants with good knowledge were more likely to have positive attitudes and good preventive practices (11) and another study found that knowledge of the mode of transmission, consequences of the disease, and preventive measures were significantly associated with prevention practices (10). This educational intervention was conducted in onchocerciasis endemic communities of southern Ghana to investigate its suitability as an effective tool to provide accurate knowledge and promote positive attitude and effective prevention practices that could lead to decreasing disease transmission in the communities.

The study showed that important aspects of knowledge and prevention of onchocerciasis, such as the organisms that cause and transmit the disease, the breeding places of the vector, symptoms of the disease, the drug used in prevention, and frequency of administration, was poor to average among residents in the communities prior to the intervention, and that the intervention was effective in significantly improving participants’ knowledge and understanding in these areas. These significant increases are important in that, with accurate knowledge of the agent and vector of the disease and of the benefit of MDAs, community members will be better able to prevent infection. An important factor is that nearly one third of participants believed that the infection is transmitted by the mosquito. With the existence of malaria and other vector-borne infections in these areas, residents do not have a clear understanding of the different disease vectors. Similar to this finding, the mosquito and various other modes of transmission were given in studies conducted in other countries (10, 11, 13). Another interesting finding is that only small proportions of participants in our study and other studies identified blindness as a symptom of onchocerciasis (10, 13). Blindness due to onchocerciasis occurs after many years if the disease is untreated (17). With the significant reduction in cases of blindness as a result of onchocerciasis control programs and community distribution of ivermectin (18), residents in these communities with ongoing onchocerciasis transmission are unaware of blindness as a debilitating and incapacitating effect of the disease. Members of these communities need to be reminded of the devastating effect of vision loss and blindness in order to increase their militancy in preventing onchocerciasis infection.

A very striking finding in this study is that prior to the educational intervention, none of the participants knew of the breeding sites of the blackflies, with more than half believing that the flies breed in dirty or stagnant water, and the remainder reporting animal waste or did not know. This finding may be due to the fact that participants knew that some mosquitoes breed in pools of stagnant water and think that this was the same for blackflies. Although participants reported that their main water sources for household use were wells or centralized tap systems, their interactions with highly oxygenated bodies of water such as fast flowing rivers and streams occurred during agricultural and domestic activities such as washing clothes, recreation, and bathing. After the intervention it was gratifying to see that most participants selected fast flowing rivers/streams as the correct breeding sites.

There were no significant changes in respondents’ selection of the season that blackflies are most abundant or the time of day that blackflies feed from the pre-test to the post-test. Most responded that blackflies were more abundant during the wet season on both tests and similar proportions believed that the flies were more likely to feed both day and night (evening) or only in the daytime. A research study conducted in Ghana reported higher monthly biting rates of blackflies in the wet season ​ (19). Similarly, participants in a study from Nigeria reported increased biting activities in the wet seasons ​ (20)​. Contrary to these studies, however, a study conducted in the Bono East region of Ghana (250–342 kilometers outside of our study sites), reported that the highest abundance and biting rates of blackflies occurred in the drier months ​ (21). Therefore, a specific study on blackfly abundance would need to be conducted in our study area to resolve this issue. Prior research suggests that blackflies generally feed during the daytime (22), and that peak hours for feeding are typically between 8:00 AM and 11:00 AM (23). It has also been reported that different species of blackflies display different biting patterns with some species such as S. damnosum showing bimodal biting activity, while other species such as S. squamosum displaying unimodal (afternoon) biting peaks (19). Therefore, the reports of community members may be accurate, and specific research would have to be conducted in the communities to identify any discrepancies.

Regarding measures to prevent blackfly bites, there was a significant increase from pre-test to post-test in participants’ choice of long-sleeved clothing. However, there was a slight decrease regarding the use of insect repellent despite this method being stressed in the presentation. It is important to note that spray-on insect repellants are not readily available or affordable in many rural areas of Ghana. Instead, individuals living in rural and/or financially limited areas are more likely to utilize mosquito coils, a cost friendly option, to protect themselves from vector-borne diseases (24). With regard to local means of treating onchocerciasis, some participants said that they knew of medicinal plants that could potentially treat onchocerciasis. A small portion of participants believed that herbal remedies such as Acheampong leaves (Chromolaena odorata), and elephant grass (Cenchrus purpureus, synonym Pennisetum purpureum) could help to protect them against the disease. Acheampong leaves, which is an anti-inflammatory (25), would be useful in treating the body’s inflammatory response to dead microfilariae, providing some alleviation of symptoms in infected persons. Additionally, elephant grass is an anti-parasitic that can counteract ocular disease by targeting infectious microfilariae that migrate to the eye and can also help treat subcutaneous parasitic infections (26). Citronella oil, which is derived from different species of Cymbopogon, is a natural occurring pesticide that can repel pests such as blackflies, mosquitoes, and ticks (27). This was not mentioned by participants but can be explored in future prevention interventions. In a study conducted in Cameroon, small proportions of participants reported using topical application of plant extracts such as palm oil and lemon juice as repellants (12). Using local remedies can be cost effective and aid in both disease prevention and treatment (28).

After the intervention, almost all participants felt that they were better prepared in treating and preventing onchocerciasis and better equipped with the knowledge to educate their peers on the disease. Participants’ attitudes towards participating in ivermectin treatment remained highly positive and increased slightly after the intervention. However, ivermectin distribution has become extremely limited as efforts to eliminate the disease have faltered in Ghana (29). Financial constraints in the country, and hence in the communities, result in decline in ivermectin distribution and treatment. Community health workers/drug distributors are not well compensated for their work. This is demotivating in their attempts to provide ivermectin, further limiting collective efforts of eradicating onchocerciasis (30).

We found significant increases in participants’ knowledge, attitude, and prevention scores as a result of this onchocerciasis educational intervention. This shows that a culturally appropriate, community-based educational intervention addressing gaps in KAP of onchocerciasis can be effective in improving KAP of residents in the short term, and could be an effective tool for improving onchocerciasis literacy and prevention practices in vulnerable communities. Addressing gaps in knowledge of the cause, vector, and symptoms (especially blindness) of the disease, and clearing up misconceptions about the breeding sites of the blackfly are crucial in controlling transmission. The highly significant increases in participants’ attitude and prevention practices scores after the intervention indicate that participants were better prepared in preventing onchocerciasis and in educating others in the community. We recommend a longer term follow-up of the intervention to assess sustainability of knowledge and implementation of prevention practices, as well as, repeating this educational intervention in other endemic communities. The presentation should be updated to include information on the occurrence of the temporary and self-limiting side effects of ivermectin (itching, edema, musculoskeletal pains, and worsening rash) due to the acute inflammatory response (Mazzotti Reaction) from the drug’s microfilaricidal effect (31, 32) as well as the more serious adverse events such as postural hypertension (31, 32) and neurological events (33) and their management. Emphasizing the length of survival of the adult worms in the skin and the need for recurrent long-term administration of ivermectin to clear the infection and prevent serious disease manifestations is important in helping community members understand the need for continued biannual participation in MDAs.

There are limitations of this study that should be considered in interpreting the results. The study recruited a convenience sample and so the findings are not generalizable to all members of the communities. Also, community members who were away from their homes or at their farms during the times the study was conducted could not participate, limiting the generalizability of results. Further, residents who self-selected to participate in the study may differ from non-participants in ways significant to the research and can affect interpretation of the results. The short time between the intervention and the KAP post-test evaluation is a limitation of this study since it may have influenced the positive results obtained and does not allow for examination of retention and implementation of KAP practices. Another limitation is that the PowerPoint presentation used for the intervention is limited in producing sustainable impact. However, we prepared and handed out pamphlets containing information used in the presentation that might serve to reinforce and constantly remind community members about the cause, transmission, and measures of prevention of onchocerciasis. There is also the likelihood of recall bias and social desirability bias by participants in answering some questions. Important strengths of the intervention is that local Community Health Workers/Promoters were trained by the study investigators and were supported in conducting the tests and giving the PowerPoint Presentation. These Community Health Workers/Promoters also have access to the pamphlets designed by the research team and handed out to study participants and other community members and can serve as a source of continued implementation of KAP activities in the communities.