The Federal Ministry of Agriculture and Rural Development (FMARD) in Nigeria has confirmed the presence of one case of Anthrax disease in a mixed livestock farm located in Niger State. This marks the first reported animal case in Nigeria since the West Africa outbreak began in Ghana in June 2023.
On July 13th, 2023, the farm reported the sudden deaths of eight (8) livestock, with the animals displaying bleeding from external orifices without blood clotting. As a response, samples were promptly collected from various species on July 14th, 2023, and sent to the National Veterinary Research Institute (NVRI) in Plateau State for testing. The results from the NVRI confirmed the presence of anthrax in the samples.
Authorities are currently conducting further investigations to identify the source of the infection and to monitor its spread to other farms and humans. While human exposure has been reported, there have been no documented cases of human symptoms or mortality so far.
In response to the situation, the FMARD and the Nigeria Centre for Disease Control and Prevention (NCDC) are working closely with the Niger State Ministries of Health and Agriculture to identify, isolate, and monitor all individuals who may have been exposed. The NCDC has activated its incident management system (IMS) at level two (2) to facilitate an effective coordination of the response. Risk assessment by the human health sector indicates a high likelihood of an outbreak and its potential impact on humans.
The FMARD’s quick diagnosis and early intervention within 48 hours of detecting suspected animal deaths have been crucial in managing the situation. The Nigerian Government, along with the FMARD, NCDC, and other one-health stakeholders, have been crucial in managing the situation. The Nigerian Government, along with the FMARD, NCDC, and other one-health stakeholders, have implemented measures to promptly detect, control, and contain any Anthrax outbreak in the country.
These measures include:
- They established the One-Health Anthrax Technical Working Group to lead and coordinate the national response.
- Both the FMARD and NCDC activated the National Incident Management System.
- An Incident Manager was appointed to oversee and coordinate the response concerning human health.
- Contact tracing efforts have been initiated to identify and monitor individuals and livestock exposed to the initial cases.
- An incident action plan (IAP) has been developed to guide the response in the event of confirmed human cases.
- Medical countermeasures and essential supplies, including medications and personal protective equipment (PPEs), have been prepositioned.
- Necessary laboratory consumables for diagnoses have also been propositioned to ensure efficient testing and analysis.
An Overview of Anthrax Disease
Anthrax is a highly infectious and potentially deadly disease caused by the spore-forming bacterium Bacillus anthracis. It is primarily a disease of animals, particularly herbivores like cattle, sheep, and goats, but it can also affect humans. Anthrax has a significant impact on both animal health and public health, making it a matter of concern for veterinary and medical authorities worldwide.
Classification of Anthrax Disease
Anthrax can be classified into several forms based on the route of transmission and the primary site of infection. These include:
1. Cutaneous Anthrax Disease
Cutaneous anthrax is the most common form and occurs when spores come into direct contact with the skin. This typically happens through wounds, cuts, or abrasions while handling contaminated animal products or materials. A painless ulcer or sore with a characteristic black center (eschar) develops at the site of infection. While cutaneous anthrax is rarely fatal with appropriate treatment, it can cause significant morbidity if left untreated.
2. Inhalation Anthrax Disease
Inhalation anthrax, also known as pulmonary anthrax or Woolsorter’s disease, is the most severe and deadly form of the disease. It occurs when individuals inhale anthrax spores present in contaminated animal products or environments, such as wool, hides, or soil. The spores can be inhaled into the lungs, where they germinate and cause severe respiratory symptoms. Inhalation anthrax is often characterized by flu-like symptoms that rapidly progress to severe respiratory distress, shock, and, in most cases, death if not treated early and aggressively. This form is particularly concerning as it can also lead to person-to-person transmission in rare instances.
3. Gastrointestinal Anthrax Disease
Gastrointestinal anthrax results from ingesting anthrax-contaminated food, usually undercooked or raw meat from infected animals. This form is rare in humans but can cause severe gastrointestinal symptoms, such as abdominal pain, nausea, vomiting, and bloody diarrhea. Gastrointestinal anthrax is associated with a high mortality rate if not promptly diagnosed and treated.
4. Injection Anthrax Disease
Injection anthrax is a recently identified form of the disease and is linked to the use of contaminated drugs derived from animal products, particularly in intravenous drug users. This form can result in severe systemic illness and carries a high risk of mortality.
Mode of Transmission of Anthrax
The primary mode of transmission of anthrax to humans is through direct or indirect contact with infected animals or their products. Anthrax spores, which are the dormant and resistant form of the bacterium, can persist in the environment for extended periods.When animals consume spore-contaminated soil or feed, they become infected, and the spores multiply within their bodies, leading to the release of large numbers of spores into the environment through carcasses or bodily fluids.
Humans can acquire anthrax through the following routes:
- Direct contact with infected animals or their tissues, such as slaughtering, butchering, or handling sick animals.
- Inhaling spores from contaminated animal products, such as wool, hair, or bone.
- Ingesting undercooked or raw meat from infected animals.
- Rarely, through the use of contaminated drugs derived from animal products.
It’s important to note that anthrax is not typically spread from person to person, except in the case of very close contact with bodily fluids from an individual with inhalation anthrax.
Signs and Symptoms of Anthrax in Livestock and Humans
Signs and Symptoms of Anthrax in Animals
- Sudden Death: In many cases, anthrax-infected animals may die suddenly without any visible signs of illness.
- Bleeding and Swelling: Infected animals may display bleeding from natural openings, such as the nose, mouth, and anus, as well as swelling in various body parts.
- Respiratory Distress: In cases of inhalation anthrax, animals may exhibit severe respiratory distress, gasping for breath, and increased respiratory rate.
- Fever: Infected animals often experience a high fever as a result of the bacterial infection.
- Lethargy: Affected animals may appear weak, lethargic, and disoriented.
- Skin Lesions: Some animals may develop ulcerative skin lesions, particularly in cutaneous anthrax cases.
Signs and Symptoms of Anthrax in Humans
Anthrax in humans can present in different forms, each with its own set of symptoms. The three main types of anthrax and their associated signs and symptoms are as follows:
Cutaneous Anthrax
- Begins as a small, itchy bump that resembles an insect bite.
- The bump develops into a painless sore with a characteristic black center (eschar).
- Swelling and redness may occur around the sore.
- Lymph nodes in the affected area may become swollen.
- Inhalation Anthrax:
- Initial symptoms are flu-like and may include fever, fatigue, cough, and muscle aches.
- As the disease progresses, severe respiratory distress and chest discomfort develop.
- Gastrointestinal symptoms, such as nausea, vomiting, and abdominal pain, may occur in some cases.
Gastrointestinal Anthrax
- Symptoms can include fever, abdominal pain, and bloody diarrhea.
- Nausea, vomiting, and loss of appetite may also be present.
It’s important to note that inhalation anthrax is the most severe form and can rapidly progress to severe respiratory failure and shock. Early diagnosis and treatment are critical for survival.
People At Risk of Contracting Anthrax
- Livestock Farmers and Handlers: Individuals working closely with livestock, including farmers, ranchers, and veterinarians, are at increased risk of exposure to anthrax spores.
- Slaughterhouse Workers: People involved in the processing of meat and animal products may come into contact with infected animals or contaminated materials.
- Individuals in Endemic Regions: People residing in regions with a history of anthrax outbreaks or areas where the disease is endemic are at higher risk of exposure.
- Intravenous Drug Users: The recent emergence of injection anthrax highlights the risk for intravenous drug users who may use contaminated drugs derived from animal products.
Prevention of Anthrax in Humans and Livestock
Preventing anthrax outbreaks requires a multifaceted approach that involves both veterinary and public health measures. Here are some key preventive strategies:
For Livestock Farmers:
Regular veterinary surveillance and monitoring of animals to detect any signs of illness or unexplained deaths.
Vaccination of livestock with licensed anthrax vaccines to provide immunity and reduce the risk of transmission.
Proper disposal of animal carcasses to limit the release of spores into the environment.
Implementation of strict biosecurity measures to prevent the entry and spread of anthrax on farms.
Educating farmers and workers about the risks of anthrax and the importance of prompt reporting of suspected cases.
For Humans:
Avoiding direct contact with sick or dead animals, especially those with unexplained deaths.
Using personal protective equipment (PPE) such as gloves and masks when handling animals, animal products, or contaminated materials.
Practicing safe food handling and ensuring that meat is properly cooked to kill any potential anthrax spores.
Staying informed about anthrax outbreaks in the region and following the advice of public health authorities.
Seeking immediate medical attention if exposed to anthrax or experiencing symptoms, especially in regions with known anthrax activity.
Conclusion
Anthrax remains a significant public health concern in Nigeria and globally, given its impact on both animal and human health. A comprehensive approach that combines early detection, vaccination, proper handling, and public awareness is crucial to preventing and controlling anthrax outbreaks. By understanding the disease and implementing effective preventive measures, we can work together to minimize the impact of anthrax on livestock, humans, and the community as a whole.