Status of contagious bovine pleuropneumonia (CBPP) in Nigeria with
emphasis on control strategies

Foluso E. Fasanmi

Federal Department of Livestock and Pest Control Services, Federal Ministry of Agriculture and Rural Development, Area 11, Garki, Abuja, Nigeria.

Introduction

Projections based on the Livestock population census of 1991, estimated the cattle population in Nigeria at 16 million. Over 90% of these are kept under Nomadic production systems, while about 10% are raised under intensive production systems. The nomadic culture of Nigerian herdsmen coupled with the practice of transhumance has significantly contributed to the spread of diseases in Nigeria particularly contagious bovine pleuropneumonia (CBPP). CBPP is an infectious disease of cattle caused by Mycoplasma mycoides subspecies mycoides SC. It is presently the most important cattle disease in Nigeria. The effects of this disease on livestock production, its productivity and on the rural economy are considerable. Economically, the country suffers direct losses through infection and deaths of cattle, while indirect losses include exclusion from participation in International livestock and livestock product trade.

Over the years, efforts were made by the Nigerian Government to effectively control the disease with varying degrees of success. The disease was virtually eradicated from the country by 1965, following ten years of mass vaccination programme, well organized disease reporting, efficient laboratory diagnosis, effective quarantine and strict control of cattle movement (Anon, 1975a, 1975b; Chima, 1999). Unfortunately, with the outbreak of the Nigeria Civil War and the consequent breakdown of the necessary surveillance measures, the disease regained its prominence. However, the present government in collaboration with the PACE programme in Nigeria is putting measures in place to frontally address the issues.

Epidemiology

The first incidence of the disease in Nigeria was recorded in 1924 when reliable records were first available. This was the year when laboratory facilities for vaccine production and serological diagnosis were carried out in Vom. Between 1924 and 1960 an average of 200 outbreaks occurred each year and mainly in Borno and Kano Provinces of the then Northern Nigeria. During the period 1960 up to 1975, the distribution of CBPP in Nigeria was categorized broadly into three zones with the far North being Enzootic, the Middle/Central belt States Exposed, while the Southern States were regarded as Free of the disease. The North Western State was the most affected as the CBPP status records indicated in Table I. The low vaccination figure for 1973 - 1974 was due to deployment of staff for National Census Operation.

Table I. CBPP Outbreak Record of North Western State (1970 to 1974)

During the 1970s up to the 1990s, the socio-economic and cultural settings of the producers/herdsmen changed. Despite the transhumance and trade cattle movement from North to the Southern States of Nigeria, which became more rapid due to adoption of vehicular transportation, there developed large-scale settlements of herdsmen within the South Western States and the South Eastern States. These Pastoral settlements were triggered by these factors; presence of few Grazing Reserves set up then by the Federal Government and the considerable increase in both manpower and infrastructural development in both public and private veterinary sectors. All these changes impacted tremendously on the livestock disease profile in the country, particularly CBPP. The disease therefore had a gradual spread beyond the traditional far North to the Southern States. As at today the whole country is considered as endemic.

Unfortunately the disease reporting system, which was efficient in the 1960s and 1970s, witnessed a setback during the 1990s. The further fragmentation of the country into many more autonomous States coupled with the lack of efficient communication system and the general downturn in the economy overstretched the efficiency of the Federal Department of Livestock and Pest Control Services as well as the State Veterinary Departments. This is evident from the gross under-reporting of outbreaks of CBPP as shown in Table 2.

Table 2. CBPP Outbreak in Nigeria (1995 - 2001)

The above table is definitely not a true reflection of outbreak status of the disease. The disease is under-reported to the Federal Department of Livestock and Pest Control Services by the relevant State and Local Government Veterinary agencies as well as from private veterinarians. Judging by the large number of CBPP samples sent and screened by Vom (Personal communication) the disease is definitely on the increase nationwide despite control measures. Gongola and Bauchi States are worst hit by the disease. Frequent cases of “vaccine breaks” were reported in the two areas between 1991 - 1998.

Quoting Dr. Joel Chima (CBPP Laboratory, Vom), “A ‘live with the disease’ attitude has prevailed in the last few years. Farmers hardly report cases but resort to treatment with antibiotics like any other bacteria disease”, (Chima, 1999; 2001). Data on infection within the country is inaccurate and subjective (Chima 2001, Molokwu 2003). Questions as to the disease socio-economic importance, efficiency of currently used vaccines, diagnostic capabilities, and effectiveness of antibiotics treatment remained unresolved. But with the advent of the FAO/IAEA coordinated Research Project on the Monitoring of CBPP in Africa in 1999 and the FAO/OIE/IAEA PACE programme in year 2002, there has been a complete reinforcement of the capacity for CBPP diagnosis in Vom (FAO/IAEA Coordinated Research Project on CELISA diagnosis of CBPP 1997 - 2002). Also with the CBPP Vaccine Revamp Task Force put in place in Vom (2002) and the current PACE programme on surveillance, serological monitoring and Rural participatory appraisal, questions about CBPP epidemiology will be clearly understood and answered soonest.

Strategies for Control of CBPP

Past Efforts

As mentioned earlier, Nigeria has made several efforts in the past to control CBPP. These efforts include the Joint Project (JP 28) of 1960s and the 3-Year National CBPP Programme in the early 90s. Under the JP 28, control of CBPP was attempted through a policy of compulsory mass vaccination in the enzootic areas of the country. This was to be followed by testing, quarantine and slaughter of affected animals. During the 70s, serious problems were encountered with the mass vaccination programme due largely to the refusal of producers to allow vaccination of their animals due to post-vaccination reactions experienced then. Subsequently, emphasis was placed on outbreaks notification, slaughter and compensation for infected animals as well as vaccination of in-contact herds. Unfortunately, the results recorded were not as encouraging as envisaged.

The three-year National CBPP Programme launched by the Federal Government of Nigeria in 1992 was also discontinued due to lack of funds. The inability of past efforts of government to achieve expected goals could be summarized as follows:

• Lack of sustainability especially in relation to continuous and sufficient funding;

• Post-vaccination reactions encountered in some animals with attendant refusal of most pastoralists to present their animals for further vaccination;

• Inability of Government to adequately compensate for condemned animals or parts thereof. The pastoralists considered government as not being sincere and sensitive in her plans to control the disease;

• Inadequate policy framework on livestock disease control in the country.

New Policy Thrust

To adequately address the problem of CBPP, the government in Year 2001 put in place a new control strategy. This strategy comprised two approaches, viz:

(i) Containment Phase: In this phase, the strategy is to reduce the incidence of the disease to about 10% through 90% vaccination of the national herd. This involves the following:

(a) Mass compulsory annual vaccination of cattle for a continuous period of 5 years;

(b) Control of cattle movement and the introduction of ECOWAS transhumance certificates;

(c) Strengthening of epidemiological surveillance networks. This is being carried out through Nigerian PACE;

(d) Improving the epidemiological and economic knowledge of the disease in the country;

(e) Mass extension programme to enlighten farmers and other stakeholders on the disease.

(ii) Eradication Phase: This is aimed at total eradication of the disease from 10% infection rate to zero. This shall basically involve compulsory test, slaughter and compensation in designated areas to be classified as Disease Free Zones (DFZ).

The following actions shall be taken in the CBPP disease free zones (but exposed):

• Establishment of sanitary cordon (buffer zone and sero-surveillance zone) to protect the DFZ;

• Active surveillance in the DFZ and surveillance zones;

• Mass vaccination of cattle in the buffer zones;

• Implementation of strict procedures for admittance of animal within the DFZ (animals destined for slaughter, breeding stock and transhumants).

Role of NVRI, Vom in these Strategies

NVRI, Vom plays vital role in the strategies for CBPP control through disease diagnosis. CBPP diagnosis involves the use of the cELISA as the standard test along with CFT. For control and prevention, NVRI produces CBPP vaccine, which has undergone recent improvement to enhance its immunogenicity. The just created 5 zonal laboratories in addition to the existing 15 NVRI State Laboratories have improved on the distribution of vaccines nationwide with emphasis in cold chain maintenance and also provide professional technical support to state veterinary services in disease diagnosis.

Conclusion

In any strategy to control disease in livestock, early diagnosis is cardinal. The reporting and documentation of outbreaks is also paramount. The potential for all these requirements is also in place in Nigeria.

The 5 years CBPP mass vaccination, which started 2 years ago, is having a positive effect on getting vaccination up to 70% coverage. This will reduce the incidence of CBPP.

Nigeria had taken a very active part in International disease eradication programmes and continues to show keen interest in liaising with neighbouring countries to control and effect total eradication of diseases that plaque our livestock industry.

Acknowledgements

Many thanks are due to Dr. J. U. Molokwu of NVRI, Vom and for Dr. E. Nwakonobi of my Department for their assistance in collecting the data and to Dr. K. A. Majiyagbe of NVRI, Vom for review of the manuscript. The author is also grateful to Mr. A. O. Edache, Permanent Secretary of the Federal Ministry of Agriculture and Rural Development for permission to publish this paper.

References

Anon (1975a) Zoo-Sanitary position of major livestock diseases in Nigeria and regional cooperation in Animal Health. Report, Veterinary Public and Animal Health Division, Federal Livestock Department, Federal Ministry of Agriculture and Rural Development, Nigeria, Bull. Off. Int. Epiz. 83, 901-922.

Anon (1975b) Nigerian Report on Contagious Bovine Pleuropneumonia XLIII Session General Rapport, Bull. Off. Int. Epiz.302.

Chima J.C., Mohammed, A., Lombin, L. H., and Majiyagbe, K. A. (1999). Field Validation of a monoclonal antibody-based competitive ELISA for the detection of antibodies to contagious bovine pleuropneumonia Proceedings, 2^nd RCM of IAEA/FAO CRP on Monitoring of CBPP in Africa using ELISA held in Lusaka, Zambia, 27 September - 1 October 1999.

Chima, J.C., Lombin, L.H., Molokwu, J.U., Abiaye, E.A., and Majiyagbe, K.A. (2001). Current situation of contagious bovine pleuropneumonia in Nigeria and the relevance of CELISA in the control of the Disease. A Paper presented at the Research Coordination Meeting of the FAO/IAEA Coordinated Research Programme held in Nairobi, Kenya. June 2001.

Molokwu, J.U. and Nwanepa, N. (2003). Diagnosis and Monitoring of Contagious Bovine Pleuropneumonia: The Nigerian Situation, National Veterinary Research Institute Seminar Series, August 28^th 2003. (In press)