Control of Bovine Tuberculosis in Malawi

16.6.1 Vaccination

BCG vaccination was used from the early 1960s to the 1970s in an attempt to control BTB in Malawi following a decision by the Department of Veterinary Services that the test-and-slaughter policy was impracticable, and that it would not allow eradi­cation of BTB from the northern part of Malawi.

16.6.2 Test-Und-SlaughterPolicy

Currently, due to cost and the lack of awareness, surveillance of BTB is not regularly conducted in Malawi. In one report only 19.0% of the farms reported ever testing their animals for BTB; the remaining 81% have never been tested (Tebug et al.

2014). It is clear too that the test-and-slaughter approach to control BTB is not easy to implement unless it makes provision for compensation for financial losses fol­lowing slaughtering of the positive reactors. Because of financial and other con­straints, and other priorities, the Malawian government is currently not in a position to fund such a campaign.

An approach that is practical and that will be embraced by all stakeholders, including the government allowing the control of the disease is outlined below:

1. Screening for BTB in Malawi should be based on immunological reactions, specifically the tuberculin skin test, because the few and non-specific clinical signs of BTB do not allow a clinical diagnosis of the disease ante-mortally (Berggren 1981).

2. As is the case in many of the neighboring countries (Kankya et al.

3. There are two broad categories of cattle husbandry in Malawi: the smallholder dairy sector (MBGs) and the dipping tank group. The two management groups carry different burdens of the infection, and it is essential that priority be given to control programs directed at one or the other based on an objective assessment of the public health risks that they pose in Malawi. Control programs can then be expanded to other sectors when capacity allows.

In the interim, there are several measures that could be applied immediately in each sector to halt the spread of BTB in Malawi:

Control Activities in MBGs Small-scale dairy farming is still nascent in Malawi. Farmers, mainly women and those from underprivileged communities, usually acquire dairy cows through loans or as gifts from aid organizations in an attempt to bolster food security. Several of these donors, particularly the NGOs, also provide basic training in dairy management and health as part of the loan process, coined as the pass-on program, that can easily be extended into BTB awareness programs. Furthermore, the Department of Animal Health and Livestock Development should partner with aid organizations to make sure that heifers/cows originate only from BTB-free farms, and that they are tuberculin-tested before relocation to ensure that the newly established farms are BTB-free. It is also important to ensure that these cattle are housed in well-ventilated, clean premises and that they are isolated from other animals that are potentially infected with M. bovis.

The existing MBGs, composed on average of 42 members, are registered locally and have fairly adequate access to services and markets (Tebug et al. 2012; Kaneene et al. 2016). For the purpose of BTB control, each MBG should be treated as an epidemiological unit.

Control Activities Involving Dipping Tank Groups These herds are rounded-up periodically, and it is important to consider each dipping tank (area) as an epidemi­ological unit when devising BTB control strategies (Bedard et al. 1993). The lack of farmer cooperation when undertaking BTB surveys at village level, which requires farmers to present their animals at a dipping station (often located 10-15 km from a village) on two successive occasions at a specific time interval, previously resulted in the number of cattle presented for tuberculin testing being too small (Berggren 1981). Designing a BTB control program for village cattle in Malawi therefore needs a lot of thinking, and a solution to the problem should be devised.

In the interim, two activities can be implemented:

• Although it is true that only intensive strategies such as national testing programs are effective to control BTB (Brooks-Pollock et al. 2014), this approach is too costly and impractical to apply to village cattle in Malawi. As an alternative, the use of abattoir inspection, if systematically applied, can provide information about the area-based prevalence of BTB,

• Irrespective of what is done, public education is pivotal in these operations and any campaign to reduce the prevalence of BTB and zoonotic TB should be supported by comprehensive educational programs, including encouraging boil­ing milk before consumption.

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