The Economic Threat of Re-emerging Brucella
2020
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Brucellosis – a disease caused by Brucella – had its first incidence in Malta that later became endemic, infecting an average of 652 civilians and 605 military personnel in 1901-06. British surgeon David Bruce isolated this cocco-bacillus in 1886, which was later termed as Micrococcus melitensis, while the disease was known as “Malta Fever”. The microbes are seen in goats, cows, swine, & cattle – providing that this pathogen is not specific to species; the major means of infection is through occupational exposure and ingestion of contaminated milk. The genus and disease had numerous names until in 1920, it was officially renamed Brucella, and in 1940, the United States began calling the disease Brucellosis. The first identified case in the U.S is presumably from the exposure of the Spanish-American War, specifically, infection in the Philippines. (1)
Brucellosis is a zoonotic disease that could impact public health and economic status; it was previously eradicated in most developed countries but has remained to cause endemic in the Middle East, Mediterranean region, Asia, South, and Central America. (2) Based on the data, there is an average of 3,626 cases per month, ranging from April 2007 until March 2017, in China alone. (3) This type of bacteria is classified under the category of B pathogen, a potent biological warfare, and the most common laboratory-acquired pathogen. It initially affects wild and domestic animals, then transmitted to humans through respiratory contact and the alimentary system. However, the Brucella genome had been noted to be completely sequenced; the major concern is the new strain that instigated a study about its origin, taxonomy, and evolution that will further invoke revision of the brucellosis global map. (4) Originally, there were seven species under this genus, namely, 1) B. abortus, 2) B. melitensis, 3) B. suis, 4) B. canis, 5) B. ovis, 6) B. neotomae, and 7) B. microti. The B. abortus, B. melitensis, and B. suis are the most important species due to the immense impact on public health, only a few cases of B. canis, while the other types remained unequivocally no threat to human disease.
Brucellosis is known to be the most common zoonotic infection worldwide, yet, neglected regionally. The distribution of this bacterial infection has been constantly changing, which makes it formidable; it may emerge in free areas or re-emerge in previously infected areas. Hence, the epidemiological approach holds utmost importance to address, investigate, and establish reliable measures or well-formulated policies that must be implemented worldwide to control any possible outbreaks, especially of the newly introduced strains. (5) Unfortunately, there is no current vaccine available for humans to fight against brucellosis, the best means of prevention is to secure safe consumption through a veterinarian approach, such as eliminating infected animals and enhancing the immunization using RB51, a vaccine designed to produce an immune response that will raise the resistance of the animals to the disease. (6)
Despite the low mortality rate (<5%) to humans, considering treatment with antibiotics and weeks to months of recovery, it undeniably affects not just health, but both cost and work performance level. The clinical manifestation may arise as fever, fatigue, weakness, and might lead to meningitis, splenomegaly, and lymphadenopathy. (7) On the other hand, there is no cure for animals; once infected, they must be quarantined until slaughtered (6), which gives emotional suffering and intense stress to farmers who hold small livestock. In fact, in 2016, a study conducted in India revealed committed suicide amongst farmers who experienced a negative impact on livestock productivity; it showed evident grief, hopelessness, and depression around the region where brucellosis perpetuated. (8)
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In Kazakhstan, there were 1,334 cases of human brucellosis registered in 2015, approximately 21 million dollars was spent on compensation for the slaughtered animals, and 24 million dollars on animal testing, which gave an immense burden to humans and economic costs. (9) For the hospital cost for human disease, in Israel, there is an estimated higher cost amount of $57 for initial healthcare utilization and $957 one-year post-diagnosis compared to non-brucellosis cases, which includes the diagnostic procedure, medication, laboratory test, and emergency room visit. (9)
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In Spain, there is an estimated hospital cost of $5,030; in New Zealand, with an approximate cost of $2,250, Argentina's annual treatment cost is estimated at around $4,000; in Africa, treatment ranges around €9 in Tanzania, €200 in Morocco, and €650 in Algeria. Antibiotic cost is estimated at around $200 to $300 in Argentina, citing a complete health treatment cost of $1,000. (10) The effect of disease in livestock will cause weak offspring and abortion in animals, reduction of productivity, and impediment of trading. Most of the communities that suffer from the greatest numbers of outbreaks are from low-income countries with poor resources, which deprives household income to farmers due to the unfortunate losses and limited marketing opportunities, while the effect at the national level is decreased availability of food and economic decline. (11) The lack of medical and veterinarian effort contributed to the rising numbers of underreported cases and insufficient monitoring of data. The problem also remained unchallenged due to mistrust in the intervention of the government and the presence of social stigma. In India, for example, have a religious belief that practice testing and slaughtering the entire herd if there is an infectious disease even in a single animal, which, in consequence, builds fear in farmers, resulting avoidance of animal diagnostic tests. (8)
There is a threat in neglecting the Brucella, especially in low-income countries where it is predominant. The burden on livelihood and human health will continue if it persists to be uncontrolled. (11) The most effective approach to reduce the prevalence of brucellosis is through vaccine campaigns, education, community outreach, and accurate surveillance of the disease, which are the cornerstones of the efforts. However, it is difficult to differentiate vaccinated from naturally infected animals on serological diagnostic tests, which is a crucial step for the assessment of the vaccination program. Hence, the first step is to develop the vaccine and diagnostic tools. (8) It is preferable if the availability of a vaccine to humans is also invented, especially since studies from sub-Saharan Africa showed an expected doubled demand for meat and livestock products by the year 2050. (11)
References
1. Benedek T. Brucellosis Therapy: A Historical Overview. Antimicrobe Organization. Web site. http://www.antimicrobe.org/h04c.files/history/Brucellosis.asp#:~:text=History%20of%20Brucellosis&text=In%201886%20David%20Bruce%20(1855,with%20other%20diseases%2C%20especially%20malaria. Accessed November 25, 2020
2. Brucellosis. World Health Organization. Web site. https://www.who.int/ith/diseases/brucellosis/en/. Accessed November 25, 2020
3. Guan P., Wu W., Huang D. Trends of Reported Human Brucellosis Cases in Mainland China from 2007 to 2017: An Exponential Smoothing Time Series Analysis. Environmental Health and Preventive Medicine. 2018; vol. 23 (23).
https://environhealthprevmed.biomedcentral.com/articles/10.1186/s12199-018-0712-5. Accessed November 26, 2020
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4. Taleski V., Zdravkovska M., Simjanovska L., et. al. An Update on Brucellosis: Endemic and Potential Global Re-emerging Zoonotic and Foodborne Disease. Acta Microbiologica Bulgarica. 2017; vol. 33 (3). pp. 111-114. http://eprints.ugd.edu.mk/18806/. Accessed November 26, 2020
5. Massis F., Zilli, K., Donato G., et. al. Distribution of Brucella Field Strains Isolated from Livestock, Wildlife populations, and Humans in Italy from 2007 to 2015. The National Center for Biotechnology Information. 2019; vol.14 (3). DOI: 10.1371/journal.pone.0213689. Accessed November 26, 2020
6. Facts About Brucellosis. Animal and Plant Health Inspection Service. Web site. https://www.aphis.usda.gov/animal_health/animal_diseases/brucellosis/downloads/bruc- facts.pdf. Accessed November 26, 2020
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7. Brucellosis. Mayo Clinic. Web site. https://www.mayoclinic.org/diseases- conditions/brucellosis/symptoms-causes/syc-20351738. Accessed November 26, 2020
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8. Franc K.A., Krecek R.C., Hasler B.N., et. al. Brucellosis Remains a Neglected Disease in the Developing World: A Call for Interdisciplinary Action. BMC Public Health. 2018; vol. 18 (125). DOI: https://doi.org/10.1186/s12889-017-5016-y. Accessed November 26, 2020
9. Charypkhan D., Sultanov A., Ivanov N., et. al. Economic and Health Burden of Brucellosis in Kazakhstan. Zoonoses and Public Health. 2019; vol. 66 (5). DOI: https://doi.org/10.1111/zph.12582. Accessed November 26, 2020
10. Rossetti C., Arenas-Gamboa A., & Maurizio E. Caprine brucellosis: A Historically Neglected Disease with Significant Impact on Public Health. PLOS Neglected Tropical Disease. 2017; 11(8). DOI: https://doi.org/10.1371/journal.pntd.0005692. Accessed November 26, 2020
11. Omary M., Kayunze K., Sitali D., et al. Socio-economic Impact of Brucellosis on Livestock Farmers in Southern and Western Provinces, Zambia. International Journal of Technical Research and Application.2016; vol. 4 (6) pp.204-209 204. https://www.ijtra.com/view.php?paper=socio-economic-impact-of-brucellosis-on-livestock- farmers-in-southern-and-western-provinces-zambia.pdf. Accessed November 26, 2020