At the recent 222nd inaugural lecture of the University of Benin, a Professor of Parasitology, Evelyn Uwa Edosomwan x-rays the predisposing factors responsible for parasitic diseases and advocates public health education as panacea to reduce invasion of parasites and their transmission to new hosts
The topic was attention-arresting and one that united both town and gown – Invasion of Territories without Limits: Parasites and their Hosts. It was the 222nd inaugural lecture of the University of Benin, Benin City, Edo State delivered recently by Evelyn Uwa Edosomwan, a professor of parasitology. Edosomwan, who presented her lecture before a quality audience comprising the academic community led by the vice chancellor of the university, Osasere Faraday Orumwense, professor of mechanical engineering, as well as family, friends and special invitees, was the first female parasitologist in the department of animal and environmental biology to deliver an inaugural lecture. Succinctly capturing the import of the subject matter, Edosomwan described it as apt, “especially with the invasion of the Nigerian nation by “human parasites”.
This may be in a lighter mood but the essence was to drive home the point of the ravaging and devastating effects of parasites on the health of both humans and animals. The word ‘parasite’, according to her, comes from the Greek word ‘parasitos’ which literally means ‘situated beside food’ and was the original term used for ‘hangers-on’ or people who ate at other people’s tables. Parasites, she stated, reduce the host’s fitnessby increasing their own fitness by exploiting the hosts for resources necessary for the host’s survival, in particular by feeding on them and by using intermediate (secondary) hosts to assist in their transmissionfrom one definitive (primary) host to another. She said though parasites are small creatures, most of them invisible to the naked eyes, their activities cause infectious diseases in man, animals and plants. Parasites, Edosomwan explained, are either plants or animals adding that “of course, we have human parasites. They may be found in all living organisms. They are found in cells, tissues, organs as well as body surface. Parasites invade our bodies where they cause diseases through adverse biochemical processes and reduce our levels of socio-cultural and economic wellbeing”. Likening parasites to “terrorists” she said they “maim, kill, and have in history caused migration of people from their natural homes to other places as refugees”. Identifying protozoa, helminthes, arthropods and mollusks as four groups of animals which are of major importance as parasites, Edosomwan said these serve as agents and vectors of human and animal diseases. She noted that parasite transmission, in many instances, depends largely on the habits, feeding and mating behaviours of the host.
On dangers posed by parasites, Edosomwan said they cause untold suffering to their host whether man or animal, stressing that most of the infectious diseases of man and domestic animals in the tropics such as malaria, schistosomiasis, trypanosomiasis, onchocerciasis, taeniasis, cysticercosis, fascioliasis, and coccidiosis in poultry are mainly parasitic. These diseases, she posited, greatly impede socio-economic development. She said apart from the direct economic losses resulting from the effect of these diseases, “they are of importance to man because many of them are zoonotic i.e. they can be transmitted from animals to man. Therefore, it is imperative for scholars, academics, researchers, policymakers; in fact everyone, to be aware of the problems associated with parasitism”.
Opining that socio-cultural practices were very important in the epidemiology of parasitic infection of man, Edosomwan said many authorities believe that the customs, traditions and socio-cultural practices of rural and urban communities expose them to parasites’ invasion which leads to disease. She asserted that their unwillingness to change their ways and attitudes, even when introduced to improvement of better ways of life, is responsible for the continued invasion of hosts by parasites without limits.
Expatiating the role of socio-cultural and behavioural practices in parasite invasion and disease transmission, she referred to a study by Assefa and Kumie (2014) onbehavioural factors affecting environmental sanitation such as food handling and water use, latrine use or non-use, children activities at play, and their contact with soil and faeces. She identified some of these socio-cultural and religious practices to include Olokun rituals in rivers/streams, water baptism in rivers/streams and bathing in rivers as spiritual cleansing, and ritual ablution by Muslims before prayer and their custom of washing anus with water. Also included are fertility rites whereby women drink fresh crab fluid or snail juice, long storage of water in containers for domestic use, defecating in river banks or water shores as in the riverine areas, and defecating in secluded portions of the backyards as found in many semi-urban and rural communities. Others include the social activities of women going with their children to water source like rivers, streams and ponds to do their washing and drawing of water, the socio/recreational activity of swimming in parasites-infested streams and rivers after school or a hard day’s work in the field by children or adults, as well as occupational hazards of fishing and logging.
Edosomwan also identified behavioural practices that could trigger parasites invasion and disease transmission as putting of hand or objects in the mouth, eating uncovered or cold food, walking barefooted in nematode larvae-infested soils, stepping into infected water, not washing hands after going to the toilet, and not washing hands before eating. Others include spreading of clothes on the grass or plants, poor health care behaviours, as well as not washing fruits and vegetables before eating in the erroneous belief that ‘dirty no dey kill black man’ as people are wont to say in local parlance. To control parasites invasion, she, therefore, suggested two measures, namely preventive and use of drugs (chemotherapeutic). Under preventive measures, she recommended provision of adequate nutrition, housing, and hygienic potable water supply; good environmental sanitation, control of vectors and intermediate hosts of parasites, breeding for refractoriness to disease, use of vaccines, and early monitoring and reporting of diseases.
According to her, it had been shown that a well-fed host is able to withstand infection, while good nutrition also enhances the ability of the host to withstand infection. She posited that good housing and hygienic potable water supply militates against many enteric or orally-transmitted parasites (e.g. protozoan cysts, guinea worm). Emphasising the importance of hygiene, she explained that proper sewage disposal and drainage prevents concentration of pathogenic organisms and development of sewage breeding flies and parasite vectors. She also suggested the provision of small dips containing disinfectants in poultry houses, rotational grazing of animals, and quarantine of newly introduced animals as ways of preventing parasitic diseases. She said provision of potable water, good toilets, and best hygiene practices could also help prevent parasitic infections, while proper washing of ready-to-eat fruits and vegetables, covering of food and cooking of food especially meat products well could also prevent helminth parasites. She said simple hygiene like washing of hands before eating, cooking, and after using the toilet could prevent many parasitic diseases.
Edosomwan said the control of vectors and intermediate host of many parasites reduces the intensity of disease transmission, adding that clearing of bushes, cleaning of gutters, dislodging of breeding sites for insect vectors have reduced invasion by parasites vectors, while the use of insecticide-treated nets has reduced malaria transmission. According to the parasitologist, early detection of diseases and dissemination of such information could go a long way in stemming disease outbreaks or epidemics. In the course of her research works in Edo State, the inaugural lecturer also came up with recommendations that could help the federal, state and local governments check the transmission and spread of parasitic diseases. Some of these recommendations included that “healthcare policy be incorporated with health education as well as regular deworming of pupils by the local government authority to significantly reduce intestinal parasitic infections in schoolchildren”; that the government should invest in building markets in Edo State, and also make sure that they are maintained for the health of the people, as according to her, a healthy environment would prevent or reduce the invasion of territories by parasites.
Edosomwan could not, however, hide her frustration as a researcher which she said necessitated her paradigm shift from immunology to basic research. Disclosing that this was necessitated by the challenges faced by many African scientists, she narrated her personal experience. “When I got a job as a young lecturer in the then Bendel State University now Ambrose Alli University, Ekpoma, there were no facilities for the type of high-level research I had been doing as a postgraduate student in the University of Ibadan, so I had to turn to basic research in public health parasitology. Furthermore, on coming to the University of Benin, the story was not too different – shortage of funds, bare laboratories, lack of equipment and reagents for immunological research reagents and shortage of power. This situation is not too different from most universities in the country”.
She lamented that “with the lack of goodwill by government in terms of research funding and little or no political will to solve the issue of power in the country, high powered research will be an illusion” stressing that “even if one gets external funding and equipment, only little can be achieved without power”. Consequently, she suggested that “while waiting for the government to do the needful, we should focus on basic research and implement their findings for the improvement of our society”.
The Director, Centre for Gender Studies, University of Benin, did not also let the opportunity slip by without talking about how in the last five years she had made several contributions towards creating awareness on gender mainstreaming and gender-related issues both within and outside the University community through organizing conferences, seminars, and workshops. She was excited to announce to her enthusiastic audience the string of successes that had been recorded by the centre. She said the Centre had also prepared, in collaboration with the legal unit and other stakeholders, a gender policy for the university. “In addition, as a result of the Centre’s activities (i.e. Research work on sexual violence), the Vice Chancellor and Senate of Ambrose Alli University, Ekpoma, approved the establishment of a Gender Studies Unit in the University last year”. The icing on the cake was the research grant it received to carry out a research on “Sexual Violence Amongst Students of Universities in Edo State”. The research, she announced, had been concluded and the findings would be made public soon.