Tuberculosis and leprosy control

The TB and Leprosy Diseases Prevention and Control Programme (TLCP), at the Federal Ministry of Health was reorganized in 1994 with a view to integrate TB and leprosy control activities. The major objectives of TLCP are:

• To interrupt transmission of infection, thereby reducing the incidence of TB and leprosy
• To treat patients in order to achieve their cure and wherever possible, complete rehabilitation
• To prevent the development of complications caused by both diseases.

The basic strategy to achieve these objectives include:

• Early case detection
• Provision of adequate chemotherapy and
• Prevention of disabilities and rehabilitation of patients.

Tuberculosis

The combined Tuberculosis & Leprosy Control came into effect in 1994. In June 2000 the previous Epidemiology/AIDS Department of the MoH was re-structured and named Disease Prevention and Control Department (DPCD). The TB and Leprosy Control Programme was subsequently accommodated within this Department and the former C.O. was named Tuberculosis and Leprosy Control Team (TLCT). Other teams within this department are: HIV/AIDS/STI team, Malaria team, Integrated Diseases Surveillance Team and Other Communicable Diseases Team. Hence the term NTLCP was replaced by TLCP. This new structure facilitates easy communication and co-operation with other teams, most notably the HIV/AIDS/STI team, given the close association between HIV and TB.

The current information on the epidemiology of TB in Ethiopia is based on case notification and estimates using different methodologies. A decrease in the incidence and prevalence of TB is expected only if the result of substantially reduced transmission, following an effective control programme, outweighs the current increase in incidence. This shift in balance may take many years and possibly decades to come. All regions are now participating in the programme.. The quality of reporting from DOTS/MDT implementing zones has substantially improved in recent years and TB and leprosy case-finding and treatment outcome data are now available for 522 (89%) woredas (districts) out of a total of 585 woredas. However, not all eligible health facilities (hospitals, health centers and health stations) are yet implementing DOTS.

The increase in TB cases attributed to HIV cannot be reliably estimated until the DOTS programme covers the whole country and reporting becomes consistent for a number of years. The ongoing HIV-epidemic may be an important contributing factor in the growing caseload, taking into account the disproportional increase of reported 'smear-negative pulmonary' and 'extra-pulmonary' cases. Although there is no reliable data on the extent of HIV epidemic in rural areas where majority of the population lives, it is expected that there will be an annual HIV-associated increase of TB incidence based on HIV prevalence rates in urban centers. The treatment success rate of smear positive TB patients put on DOTS has been improving steadily over the years and currently stands at 81%. On the other hand, the rate of defaulters has dropped from 13% in 1989 to 8% in 1994 EC. However, some caution is warranted, since not all registered cases are evaluated for their outcome. The same caution should be applied to the death rate (7%), since death in hospital (before registration) and during treatment often get unreported. The decline in defaulting rate (13% to 8%) is conspicuous and may reflect programme efforts in facilitating treatment adherence.

Tuberculosis and HIV dual infection

The catastrophic association between HIV and TB has now been well identified, although the underlying causal mechanisms and immunological aspects are not yet fully understood. It appears that latent TB-infection in HIV-positive persons reactivates at a rate of 10% per year (as opposed to 5%-10% over a lifetime for HIV-negative persons). HIV-positive persons are prone to re-infection with new strains of TB from the community and drug resistance may occur more frequently. In general, TB is often the first opportunistic infection in HIV-infected persons, and active TB has been shown to induce HIV virus-replication, thus accelerating the progression of AIDS. The clinical presentation of TB may be altered in HIV-positive patients, especially in advanced stages of HIV-infection when immunity is considerably compromised. Smear-negative and extra-pulmonary forms of TB are then more common and X-ray abnormalities are atypical.

Information on the association between HIV and TB in Ethiopia is very limited. In 1994, 44% of 450 TB patients in Shashemene (Oromiya Region) were HIV positive, and 25% of 78 cases with TB of the lymph nodes, confirmed by pathology, in 1997 in Butajira (SNNPRG) were HIV-positive. A cross sectional survey of smear-positive TB patients in Addis Ababa showed 45% co-infection. Of 51 consecutive culture-proven TB patients in Addis Ababa in 2000, 47% were HIV-positive. Data generated from various regions suggest that majority of hospitalized TB patients are HIV-positive (40-70% in Amhara Region).

Existing information confirms that Treatment of Latent TB Infection (TLTBI) in HIV-positive patients is beneficial. The reduced mortality associated with cotrimoxazole prophylactic treatment (CPT) of HIV-positive TB-patients has been confirmed in at least one study.

These benefits have strong future implications for TB control in areas of high HIV-prevalence. Policies establishing and promoting Voluntary Counselling and Testing (VCT) should include these interventions. In addition, linkages between Home-Based Care (HBC) programs for AIDS patients and provision of DOTS for TB treatment at the community level are vital to TB control.