What is Brucellosis? Important Facts You Should Know!

Author: Dr Agatha Ugboma DVM, MVPH, MSc (IPH)

Reviewed by : Dr Azuka Ezeike, MBBS, FWACS, FMCOG, MSc(PH)

What is brucellosis?

Brucellosis is an infectious disease caused by bacteria of the genus Brucella. It primarily affects animals but can also affect humans. [1]. It was first recognized in Malta in the 1850s, hence the name Malta fever [2].

Brucellosis is a zoonotic disease that can spread from animals to humans. [3]. It affects people globally, but it’s mostly common in developing nations.

The World Health Organization (WHO) categorized the disease as the most commonly neglected zoonotic infection because of its substantial impact on low- and middle-income countries (LMICs) [4]. It ranks among the seven most overlooked diseases [5]. There are about 500,000 cases of brucellosis each year worldwide. [3]Brucellosis is often called undulant fever, in that the fever comes and goes like a wave, Bang fever [2], Mediterranean fever, and many other names [3].  Brucellosis is common in cattle, sheep, goats, pigs, dogs, horses, camels, and some wildlife [1] and marine mammals [2]. 

When animals are infected, they  manifest with

• Abortion,(miscarriage), 
• Infertility, and
• Joint infections. 

These can cause a huge economic loss to small-scale livestock farmers and the meat and milk industry [6] [7].

What Causes Human Brucellosis?

Several types of Brucella bacteria can affect both animals and humans. Human brucellosis, which can develop into a severe and chronic illness, is primarily associated with the following animal hosts and their respective Brucella strains:

• Cattle: B. abortus
• Sheep and Goats: B. melitensis
• Swine: B. suis [1]  

People who are at a higher risk of brucellosis are:

• Those working in slaughterhouses and abattoirs and related jobs like butchery and meat sellers, 
• Veterinarians and  para-veterinarians,
• Livestock farmers, 
• Laboratory personnel who work in the lab that handles Brucella,
• Those who eat raw meat and unpasteurized milk products.

This is due to their exposure to infected animals and animal products [8] [9] [4] [3].  

Humans can contract Brucellosis through;

• Direct contact with infected animals, tissue, blood, or body fluids,
• Breathing in (inhalation) of particles of Brucella when handling infected animals or aborted fetuses,
• Through cuts on the skin, 
• Through the eyes, nose, or mouth,
• Eating contaminated animal products, such as untreated milk and milk products (e.g., cheese),
• Eating raw and undercooked meat,
• Accidental inoculation in laboratories.

Additionally, there are several ways that human-to-human transmission can happen, such as through breastfeeding, through the placenta, and infrequently through sexual contact, organ transplantation, and blood transfusions [10]. 

Symptoms in humans take two to four weeks or longer to appear after exposure to the bacteria [3]. Symptoms can come and go for months or years, including;

•   Irregular fever, 
• Sweating (sometimes with a mouldy smell), 
•  Joint pain, especially in the hips, knee, or lower back, 
• Unexplained weight loss, 
• Chills,
• Headache, 
• Abdominal (stomach) pain, 
• Large, painful lymph nodes,
• Depression,
• Loss of appetite or upset stomach,
• Arthritis,
• Generally feeling unwell. [3][2][11]

Why Public Awareness is Crucial to Stopping Brucellosis

High awareness and understanding of brucellosis are essential for establishing proper habits and practices that help control and prevent the disease.

Anyone involved in the livestock value chain is thought to be among the highest occupational risk groups, such as farmers, pastoralists, slaughterhouse workers, animal health professionals, and laboratory personnel [12].

Public health awareness is crucial because;

•  It empowers at-risk individuals and communities to recognize, prevent, and respond to brucellosis early.

• It educates communities on safe food handling practices, such as pasteurizing milk and wearing personal protective equipment (PPE) when handling animals and animal products.

• When farmers and animal handlers understand how brucellosis spreads, they will be more likely to support measures such as livestock vaccination, regular testing, and biosecurity measures to help prevent and control outbreaks.

• It encourages people to report Brucellosis cases early, improving disease reporting, leading to more accurate data and better disease surveillance. 

• It helps health officials understand disease patterns, allocate resources more effectively, and develop targeted interventions.

By bridging the gap between public health initiatives and people's attitudes and actions, we can increase our chances of successfully controlling and eventually reducing the burden of brucellosis [13].

Barriers to Brucellosis Awareness

Some of the barriers to brucellosis awareness include:

• A low awareness of brucellosis among the public and health professionals [14] leads to underdiagnosis and misdiagnosis, as symptoms can mimic other diseases. Even the high-risk workers often don’t recognize the symptoms. [15] [16].  
• In rural areas, poverty limits access to healthcare and education about brucellosis. [17]. Individuals may prefer attending to immediate economic needs over health concerns, leading to delayed treatments and increased transmission [16].
• Cultural reliance on traditional medicine can delay appropriate treatment and hinder awareness in some communities [18].
• Poor healthcare infrastructure contributes to the persistence of the disease. Many regions where the disease is present lack adequate healthcare facilities and trained personnel who recognize and manage brucellosis cases [14] [16].
• Communication challenges such as inadequate information sharing lead to widespread misconceptions about brucellosis. Often people know little to nothing about prevention, symptoms, and treatment options [14][16].
• Brucellosis control requires strong political support and collaboration between animal and public health sectors. The lack of prioritization in many countries’ health policies. weakens awareness efforts and resource allocation [18].
• Research Gaps: More research is needed to focus on brucellosis in various livestock species, beyond cattle and small ruminants. Current diagnostic tools are often partly sensitive or specific, complicating disease management [15] [18].

Addressing these barriers through education, infrastructure improvement, and policy prioritization can reduce brucellosis cases and improve health outcomes.

Practical Ways to Educate and Protect Communities from Brucellosis

To promote understanding, acceptance, and participation in brucellosis control measures, the following strategies can be considered:   

• Collaborative Livestock Management Programs: Training livestock breeders using educational interventions such as the PRECEDE-PROCEED model will greatly improve their knowledge and behavior about brucellosis prevention, including vaccination and animal testing. This model highlights community involvement and feedback as important factors for successful implementation [19].

• Building Trust Through Transparency: Openly sharing information on the risk factors, control measures of brucellosis, and the benefits of participating in prevention programs will encourage community members to view public health efforts as reliable [20].

• Community Engagement: Engaging local leaders, community health workers, and respected figures to deliver tailored Brucellosis education. This will improve community involvement and trust and make it easier to align health messages with local cultural practices and beliefs [20].

• Culturally Adapted Awareness Campaigns: Develop culturally adapted awareness campaigns to consider cultural practices, languages, and values. For example, using stories, illustrations, or analogies rooted in local culture can make information on Brucellosis prevention more relatable and memorable [18].

• Technology Utilization: Accessible technology, such as radio broadcasts, mobile health apps, and social media, can reach broader audiences. Mobile apps or SMS services can also send timely reminders about vaccination schedules, preventive measures, and symptom recognition [21].

• Training Local Health Providers:  Equipping local health providers with knowledge and skills to recognize, diagnose, and manage Brucellosis is important for improving community health outcomes. This training should focus on clear communication about prevention measures [15].

• Public-Private Partnerships: Collaborating with non-governmental organizations [NGOs], veterinary associations, and the private sector to provide funding, expertise, and resources for sustainable awareness programs. Such collaborations can improve the reach and impact of public health initiatives to control brucellosis [22].

By fixing Brucellosis control measures within community structures and making them accessible and relevant, we can increase acceptance, promote preventive behaviours, and ultimately reduce the disease burden.

Conclusion: Looking Ahead: Preventing Brucellosis Together

Looking ahead, preventing Brucellosis requires a collaborative effort across sectors to address its economic and public health challenges, particularly in regions reliant on animal husbandry. Key strategies include routine livestock vaccination, surveillance, and community education targeting farmers, veterinarians, and the public to promote safe practices and protective measures.  

Cooperation between public health and agricultural sectors is important for effective outbreak monitoring and response. Governments and health organizations must support biosecurity policies, research funding, and healthcare for at-risk populations. By improving education, vaccination efforts, and supportive policies, we can reduce the global burden of Brucellosis and safeguard both human and animal health.

Reference:

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