Poor Application of Statutory Control Policies

The control of BTB in Africa is a tale of woe. From the early 1900s onward, TB, both in humans and animals, received little attention from the regulatory authorities and farming communities in Africa, mainly because they focused on the more visible and rapidly fatal epidemic and endemic diseases that periodically ravaged the livestock populations on the continent (Carmichael 1938).

of the African countries. This is the consequence of the provision of inadequate human, infrastructural, and financial resources and the lack of recognition by policymakers of the importance of the diseases in humans and animals and the effect that they have on the general well-being of the human population and productivity of its livestock.

In respect to BTB, the disease persists because most of the African countries do not conduct systematic national tuberculin testing of cattle. Due to socioeconomic limitations in many countries, culling of tuberculin test-positive reactors, as part of the national BTB control policy, is not routinely done, and the infected cattle remain within the system. Only 7 of the 28 African countries that consider BTB important enough to list it as a notifiable disease apply test-and-slaughter measure for disease control; the remaining countries control the disease inadequately or not at all (Cosivi et al. 1998). Only a few countries, such as South Africa (since 1969), Morocco (since 1982), Tunisia (since 1984), Nigeria (since 1988), and Tanzania (since 1997), have statutory BTB control programs though they are mostly poorly or inadequately resourced and implemented (Berrada 1993; Ben Kahla et al. 2011; Ejeh et al. 2014; Sahraoui et al. 2011; OIE 2017).

In many African countries, abattoir records are the only sources of information about the occurrence and prevalence of BTB. The situation in Ethiopia is a good example of the limited value of this approach. Here official slaughter provides only 28% of meat consumed; the remaining 72% comes from unsupervised, backyard slaughter (Etter et al. 2006), where the chances of detecting BTB are poor, and even if it should be recognized, the event will probably not be reported to the relevant veterinary officials. Even in the countries with a formal control program, the implementation is often limited, and the efforts to control the disease are inadequate as they often only focus on a small proportion of the national herd. In Tanzania, for instance, only intensive dairy farms supplying milk to the human populace in urban centers are subject to compulsory screening with the single comparative cervical test (CCT) for BTB (Jiwa et al. 1997). Although this approach makes sense from an epidemiological point of view if you have to deal with limited resources, such herds are relatively few, and a large portion of the cattle population is excluded from the control program. In some countries, tuberculin skin testing is required only when there is a need to relocate dairy cows (Berrada 1993), or to satisfy the requirements of the importing country, before being accepted for slaughter by export abattoirs (Quirin et al. 2001).

It is clear that few countries in Africa are currently applying BTB eradication schemes and those that are, generally do not meet the OIE-based standards as practiced in North America, Europe, Australia, and New Zealand. South Africa perhaps is the closest to meeting these standards, and it recently updated its control strategy (DAFF 2013), but there too, most of the emphasis is on commercial farms. Morocco [with technical support from the Food and Agricultural Organization (FAO)] may reach this goal as it completed a feasibility study for conducting a BTB control program (Berrada 2006).

The general lack of attention to controlling BTB also has an impact on humans because of their susceptibility to infection with M. bovis. Consequently diseases such as BTB, which are often associated with resource-poor communities, are now categorized in the neglected zoonoses group, and there is increasing international awareness about the risk of consuming raw dairy products (Drewe et al. 2014). The situation is compounded by the lack of knowledge about zoonotic TB. Several studies, such as in Ethiopia (Ameni et al. 2013), Tanzania (Swai and Schoonman 2012), Zambia (Munyeme et al. 2010), and Western Africa (Unger and Munstermann 2004), confirmed that farmers’ awareness about the importance of zoonotic M. bovis is suboptimal.

Tschopp et al. (2013) summarized the imminent danger of zoonoses in the burgeoning intensive dairy farms in central Ethiopia, and this probably applies to many of the poorer African countries:

Despite six decades of efforts by government and non-governmental organizations to promote dairying, general awareness of milk-borne diseases is poor. Even when farmers seem better informed of the disease situation, it does not seem to be linked with an informed control policy, and hence there is no guarantee that it will change. Currently, the main danger is the introduction of zoonotic diseases among upgraded Holstein and their crosses origi­nating from high BTB prevalence areas such as Addis Ababa and its dairy belt.

The lack of understanding of the risk and the apathy of the regulatory authorities to control the disease are exemplified by the sale in central Ethiopia of stock from a dairy farm with a very high prevalence of BTB. The entire population of cattle, many suffering from BTB, was sold to unsuspecting local dairy farmers who scrambled to buy a few of the “high genetic value HolsteinZFriesians.” This situation allowed the uncontrolled movement of BTB-infected cows from the “depopulated farm” to multiple other farms and beyond. This is the consequence of a testing program that operates outside of any legal framework and not dealing adequately with BTB-positive reactors.

Against the background of the rapid, and perhaps, overwhelming increase in the size of the African population, the current state of affairs as they relate to the threats and impact of BTB and zoonotic TB is a major cause of concern. The number of people in Africa nearly trebled from the estimated 478 million in 1980 to the current almost 1.2 billion. Urbanization increased rapidly from 27% in 1980 to the current 40%, and it is estimated to reach 56% by 2050 at which time, the continent’s population is predicted to be 2.4 billion (UN 2016; World Population Review 2018). These figures are alarming given that the African countries as a group are the poorest in the world, and the current lack of infrastructure, financial resources, food, and space are crippling limitations when planning for the future. The little attention given to BTB and zoonotic TB has the potential for them to become overwhelming animal and public health problems, with a detrimental effect on the general population far in excess of what it is currently perceived to be; this because the extent and importance of important chronic diseases that have been present from antiquity are largely unknown and uncontrolled on the continent.

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