IN Kogi, the shrill taunt of death afflicts the natives like a bad dream. The wild cries of deaths at home and the fields, haunt indigent folk of Okunran, Okoloke and Isanlu-Esa in Yagba West local council. It torments them in their sleep and as they go about their daily chores.
It started as a ‘strange disease.’ Six weeks after it berthed in Okoloke village, a settlement predominantly inhabited by Fulani herdsmen, gastroenteritis, a diarrheic ailment caused by zoonotic bacteria, has been identified as the cause of 62 deaths in Yagba West.
The State Commissioner for Health, Saka Audu, revealed that those so far diagnosed were found to be suffering from gastroenteritis and malaria.
“The disease actually started six weeks ago in Okoloke village in Yagba West, which is a settlement that is predominantly inhabited by Fulani herdsmen. There have been cases of reported deaths following abdominal pain, vomiting, and diarrhoea, but the patients who showed signs of illness had since been evacuated and transported to Kogi State Specialist Hospital Lokoja, for better treatment,” said Audu.
Gastroenteritis, according to health experts, is an inflammation of the stomach and intestines that manifests in the form of vomiting or diarrhoea. Bleeding may occur in stools and in severe cases, the victim dies. Acute gastroenteritis manifests as diarrhoea and vomiting, and fever occasionally. The disease is a major global health problem, causing about two million deaths annually among children under five years of age. The greatest burden of the disease, however, impacts in developing countries, often devastatingly, due to poor sanitation, lack of safe drinking water, and unsanitary food processing culture, argued Kola Atunbi, a medical doctor.
Atunbi stated that the most common cause of gastroenteritis is a viral infection. “It is often caused by food poisoning or contaminated water supply,” he said.
The disease’s outbreak in Okoloke, an area predominantly inhabited by herdsmen, substantiates fears across medical circuits that its transmission route in Kogi can be traced from cattle to man. The most common cause of the viral infection however, has been identified as food ingested by its human victims.
“Food infected with Salmonella, Brucella and Escherichia Coli (E. coli) can cause gastroenteritis. Meat and other poultry products, dairy milk, shellfish and parboiled rice are also common vectors of the disease. It is most likely that the disease spread faster across the affected areas as a food borne virus,” said Isabella Momodu, a public health consultant.
Momodu’s summation may not be too far from the truth. Previous outbreaks of gastroenteritis and other zoonoses have been traced beyond slaughterhouses, to neighbourhood food canteens, stalls of itinerant food hawkers and presumably standard, decent eateries and restaurants.
The fact that the current outbreak in Kogi has been traced to local cattle herds, further substantiates established medical and scientific discoveries of food-borne hazards along Nigeria’s meat value chain.
The World Health Organisation (WHO) reports that illness due to contaminated food is the most widespread health problem in the world and an important cause of reduced socio-economic productivity.
In Nigeria, there is no organised system for monitoring outbreaks of food-borne infections in humans, which explains the inability to ascertain the true nature of the crisis in Kogi, soon after the first casualty.
For six weeks, the government dithered for lack of essential and policy provisions guiding responses to an outbreak of such fatal consequences. Thus the coinage of ‘strange disease’ in describing the diarrheic outbreak that claimed 62 lives in three local governments in the state.
Reason for Kogi’s death toll
Most food-borne diseases in Nigeria appear to occur predominantly as isolated sporadic cases rather than taking the form of outbreaks and many, if not most, cases of food-borne infections are unrecognised, uninvestigated and undocumented, lamented Bodunde Hakeem, a medical lab scientist.
Corroborating him, Thelma Soaga, a public health officer, stated: “Many patients do not seek help from hospitals but rather engage in self-medication or use of medicinal herbs. It is, therefore, difficult to determine the actual incidence of food-borne infections. However, diarrhoea is a good indicator of food-borne disease and better data exist for the prevalence and impact of diarrhoea in Nigeria.”
In developing countries, typically 50 to 60 percent of diarrhoea cases are bacterial in origin. In Nigeria, the proportion may be higher at 65 to 80 per cent, according to health experts.
“Most of the bacterial causes of diarrhoea are zoonotic, that is, transmissible between animals and humans, and the most notable bacterial zoonoses are toxigenic E. coli infection, campylobacteriosis, brucellosis, cryptosporidiosis, Staphylococcus aureus (S.aureus) infection, salmonellosis, listeriosis, toxoplasmosis, and Bacillus cereus infection.
“Important non-zoonotic bacterial causes of diarrhoea include typhoid and cholera. Others such as B. cereus may be environmental contaminants as well as zoonoses. This complexity makes it difficult to estimate the relative importance of infected animals, polluted environments and infected people as sources of infection.
“Even if food-borne zoonotic pathogens are detected in humans, they are often not traced back to the likely animal source due to inadequate medical diagnostic facilities in most hospitals across the country,” explained Funmilayo Osuntuyi, a medical doctor.
A large number of studies examining food-borne hazards have established that besides Brucella, E. coli and Salmonella are two popular meat-borne hazards in the country. The E. coli strains are important food-borne pathogens responsible for gastroenteritis with manifestations of abdominal pains, bloody diarrhoea and kidney failure, especially in children. Cattle are important reservoirs of E.coli virus and contaminated meat is a major vehicle for its transmission from animals to humans.
Local fast-food restaurants commonly referred to as “bukas” are regarded as likely sources of infection. In Akwa Ibom, bloody, diarrheic E. coli accounted for 31 per cent of all cases of diarrhoea in humans, according to recent scientific findings.
A significantly higher prevalence of the virus was observed in Lagos (35.0%) with greater rate of meat consumption and more eateries than in Zaria (23.7%) which had a lower rate of meat consumption and fewer eateries.
In southeastern Nigeria, seven E. coli strains were isolated from 520 diarrhoeic stool samples from patients with acute diarrhoea in Enugu and Anambra States recently.
Food-borne viruses
Contamination can occur at multiple steps along the food chain. A previous outbreak of Salmonella food-poisoning in Ibadan, Oyo State, resulted in the death of 20 people. The outbreak was attributed to the consumption of improperly preserved sandwiches contaminated with the Salmonella virus (typhimurium phage type U282).
And just recently, 10 duplicate (20) samples of fresh meat (beef) were randomly sampled from two major markets, the Watt and Marian markets in Calabar, Cross River State by researchers Iheanyi Okonkwo, Udeze Augustine, Ani Nkang and peer across six universities including University of Port Harcourt, University of Ibadan, University of Ilorin and Federal University of Technology, Owerri, Imo State.
The meat samples were analysed microbiologically to establish rates of contamination by bacteria. Fresh meat samples from both locations, Watt and Marian markets, showed marked growth of bacteria and a total of 36 isolates comprising eight different classes of bacteria were isolated with an average incidence rate of 50% in each market.
The viruses include Klebsiella pneumoniae, E. coli, and Salmonella, and their presence in the fresh meat samples is alarming.
A series of unfortunate findings
Besides, Salmonella, E. coli and Brucella, Giardia, a diarrheic virus, has manifested in parts of the country. In a six- month scientific study of Giardia parasites among patients that attended the University of Maiduguri Teaching Hospital (UMTH), Maiduguri, Borno State, of the 256 patients examined, 85 (33.2%) haboured Giardia species. Of the 156 diarrhoeic patients examined, 64 (41.0%) tested positive to the disease, while 100 non-diarrhoeic patients, 21 (21.0%) were also infected. The even spread of infection among patients has been described as endemic in Maiduguri.
Giardiasis is usually associated with contaminated water supplies, poor personal hygiene, ignorance and poverty. The diarrheic virus is also transferrable by vectors such as housefly and it is responsible for over three million deaths annually, mostly in children. However, despite the danger constituted by the disease, there is still dearth of information and proactive campaign against Giardiasis and other zoonoses in Maiduguri.
Leptospirosis, a zoonotic disease also manifests in the country with debilitating and life threatening consequences on its human hosts. The disease’s prevalence rate in Abuja, Benue, Plateau and Nassarawa States excites worry as recent screening of 263 blood samples from male and female abattoir workers in the four states showed 87.7% (male) and 81.0% (female) prevalence rates respectively.
Nassarawa State had the highest prevalence rate of 94.3%, while the least rate was found in Plateau State with 82.8%. Like Brucella and Salmonella, symptoms of Leptospira infection closely mimic those of many febrile illnesses and accurate diagnosis may be missed due to its similarities to other fever.
Human leptospirosis manifests as a wide spectrum of clinical illnesses, ranging from mild infections to severe multi-organ failure associated with high mortality and morbidity in different countries. It is transmitted to humans via direct or indirect contact with water, food or soil containing blood, urine and tissue from an infected animal.
It infects the body through mucous membranes of the eyes, nose and mouth, or abraded skin by bathing or accidental immersion in fresh water lakes, rivers or canals contaminated with the urine of the infected livestock. Livestock often contract the disease from rats.
The disease has also been reported in Enugu, Oyo and Bauchi among cattle, abattoir workers and volunteer blood donors. Despite its significance as a public health threat, leptospirosis is rarely diagnosed in most health care facilities in the country.
Antibiotic-resistant viruses
Listeria and E. coli isolates from muscle tissues of slaughtered cattle at a Bodija municipal abattoir in Ibadan, Oyo State revealed that meat is prone to contamination by antibiotic-resistant strains of the viruses, during slaughter and processing, due to unhygienic practices by abattoir workers.
A research team including Victoria Adetunji and Tajudeen Isola of the Department of Veterinary Public Health and Preventive Medicine, University of Ibadan (U.I) “found that the muscle tissues from the slaughtered cattle were highly contaminated, with the total aerobic, coliform and Listeria counts being higher than the acceptable international standards. Isolated E. coli and Listeria demonstrated 100 per cent resistance to all tested antibiotics,” according to the team.
Apparently, majority of the viruses responsible for diarrhoea in Nigeria are zoonotic and cattle are important reservoirs for many. In recent hospital studies, 33 out of 116 patients examined, had a history of meat consumption shortly before the onset of symptoms.
Worried by high incidences of zoonotic infections in humans, the Federal Department of Livestock, four Nigerian universities teaching veterinary medicine, the Directorate of Research of the National Veterinary Research Institute, the Nigerian Institute for Trypanosomiasis (and Onchocerciasis) Research and Chief Veterinary Officers from selected states, and representatives of the private sector, met with International Livestock Research Institute (ILRI) scientists at the International Institute of Tropical Agriculture, Ibadan, Oyo State, to deliberate and address the country’s zoonoses burden.
The forum identified food as a gendered commodity, with men and women typically playing different roles in livestock production and processing, with implications for food safety.
The health experts warned that the general public is at high risk of contracting food-borne viruses through the consumption of contaminated food and abattoir workers are at greater risk of exposure.
However, because the number of consumers of meat is greater than the number of people working closely with animals and their products, the greatest burden of infection is borne by consumers.
There is no gainsaying that beef is the most commonly consumed meat in Nigeria thus increasing its potential contribution to the food-borne diarrhoea burden. The cost of illnesses associated with food-borne and beef-borne diarrhoea in the country was estimated by the Nigerian and ILRI scientific think-thank as follows: 173 million episodes of diarrhoea in the country is attributable to food and 35 million episodes of diarrheic ailments are attributable to beef.
The cost of diarrhoea are US$ 3.6 billion (about N1.3 trillion) and the cost of food-borne diarrhoea are US$ 2.0 billion (about N724 billion). The cost of beef-borne diarrhoea from treatment and lost income is US$156 million (about N57 billion), according to the forum.
Public health officers identify a higher prevalence of zoonoses in food sellers and handlers due to the crucial role they play in the preparation and sale of food in public and the nation’s abattoirs.
Biological contaminants, largely bacteria and other parasites, constitute the major causes of food-borne diseases often transmitted through food, water, nails, and fingers of food sellers and handlers contaminated with faeces. A recent study in Abuja, Federal Capital Territory (FCT), established the prevalence of bacteria and intestinal parasites among food handlers in the FCT. Stool, urine and fingernail analysis of 168 food handlers revealed worrisome truths about their food processing culture.
Staphylococcus and E. coli viruses were found in their fingernails. The subjects’ stool samples also tested positive to Salmonella (42.3%) and Shigella (15.5%) viruses. A high prevalence of intestinal parasites (38.1%) and bacteria (62.6%) was also discovered in the stools of the food-handlers.
Is livestock business and policy review the answer?
The use of retention ponds for pre-treatment of abattoir effluents has been suggested as an effective physical treatment method in reducing contamination levels of communal waters. Health experts also advised that entrepreneurs dealing in animal wastes such as bones, manure and blood should be encouraged through government policies to convert abattoir wastes to useful products.
Abattoir operators should be trained on hygiene methods and enlightened by the government and NGOs, on impacts of abattoir effluents on public health and the environment.
Public health practitioners also suggested that the country’s policy on livestock business and ownership should be reviewed to meet the challenges of present realities.
“Government should ban public hawking of livestock and the use of residential houses as poultry farms. These portend great health hazard to human population and could snow-ball to a deadly epidemic. It will be difficult to contain any such pandemic given the poor state of the nation’s health sector and lethargic emergency response facilities,” warned Bidemi Kalejaiye, a veterinary doctor.
Kalejaiye advised that the government and regulatory authorities should ensure that the policy regulating abattoir operations and poultry farms are strictly adhered to. The government must institute policy that outlaws the location of new abattoirs, meat markets and poultry in residential areas,” she said.
Ruth Onoshe, a food seller and resident of New Oko Oba, Agege, Lagos, however, argued that, besides the occasional stench of slurry and other animal waste that emanates from the abattoir, “No one could possibly die or fall sick by living close to an abattoir.”
She described complaints about food-borne viruses and food poisoning as exaggerated claims and false alarms. The mother of four said that she has been selling food in the Oko-Oba abattoir for four years and none of her customers had ever complained of stomach ache or food poisoning.
“See how enticing the aroma is. See how it sizzles in the pot. Taste it. It is very delicious. My food is always delicious,” said the food seller, who also believes that adding ‘curry and ginger’ to beef meal rids it of every infection.
