National population-based tuberculosis prevalence survey in Ghana, 2013

BACKGROUND: The prevalence of tuberculosis (TB) disease is one of the three main indicators used to assess the epidemiological burden of TB and the impact change of TB control; the other two are incidence and mortality.OBJECTIVE: To estimate the prevalence of TB disease among adults in Ghana.METHODS: A nationally representative cross-sectional survey was conducted. Participants were screened for TB using interview and chest X-ray (CXR). For those participants with cough ≥2 weeks and/or abnormal CXR, spot and morning sputum specimens were collected and examined by smear microscopy and culture.RESULTS: The study revealed that the prevalence of smear-positive TB among adults (age ≥15 years) was 111 (95%CI 76-145) and that of bacteriologically confirmed TB was 356 (95%CI 288-425) per 100 000 population. Males and older people had a higher prevalence than their counterparts. The majority of TB cases were smear-negative and had an abnormal CXR without reported chronic cough.CONCLUSION: The survey revealed much higher TB disease burden than previously estimated. This implies that the programme needs more effort and resources to find undiagnosed and unreported cases. The higher proportion of smear-negative and asymptomatic TB cases suggests the need to revise the existing screening and diagnostic algorithms.

Trends in extrapulmonary TB cases at three teaching hospitals in Ghana, 2008-2017

SETTING

Three teaching hospitals in Ghana.

OBJECTIVE

To elucidate trends in demographics, clinical characteristics and treatment outcomes in extrapulmonary TB (EPTB) patients.

DESIGN

This was a retrospective study involving the review and comparison of EPTB and pulmonary TB (PTB) data from 1 January 2008 to 31 December 2017 in TB registers and treatment cards.

RESULTS

Of 15,392 TB cases, 4607 (30%) were EPTB, including 4477/4607 (97%) new cases. There were 2,679/4607 (58%) males and the age range was 0.3 to 96 years. Pleural TB (1021/4607, 22%) was the most common. Treatment success rates for EPTB and PTB were respectively 72% and 84%. HIV positivity was high among patients with disseminated/miliary TB (429/779, 55%) and TB meningitis (242/526, 46%). To note, disseminated/miliary TB (χ2 = 33.53, P < 0.0001) increased, whereas TB meningitis (χ2 = 19.43, P < 0.0001) decreased over the 10-year period. Mortality among EPTB patients was associated with increasing age (⩾25 years), disseminated/miliary TB, TB meningitis and HIV positivity.

CONCLUSIONS

There is male preponderance for both EPTB and PTB in Ghana. Increasing age, disseminated/ miliary TB, TB meningitis and HIV are risk factors for mortality among EPTB patients. This emphasises the need for public education on the risk factors for EPTB and preventive strategies.

Diagnosis of tuberculosis in ghana: the role of laboratory training

OBJECTIVES

The laboratory is considered the cornerstone of tuberculosis (TB) control programme. International review of Ghana's programme in the late nineties identified the laboratory services as the weakest component. Sputum smear microscopy (SSM) being the main method of diagnosing pulmonary TB in Ghana, the training objectives were to: (i) strengthen the knowledge and skills of laboratory personnel on SSM (ii) impart necessary techniques in biosafety and (iii) introduce a Quality Assurance (QA) system in order to strengthen SSM services.

METHODS

Personnel were selected for training during a nationwide situation analysis of SSM centres in 2000/2001. Four training sessions on SSM/QA were held between 2001/2004.

RESULTS

A total of 80 personnel were trained: 10 regional TB coordinators and 70 laboratory personnel. The participants upon return to their respective regions also organized training within their districts. This approach resulted in another 100 district TB coordinators and 200 laboratory personnel being trained. Improvement in smear preparation, staining and reading ability of the participants were observed during the post-test and subsequent visit to their respective laboratories. The training has led to strengthening of TB laboratory services in the country and has contributed to increase in case detection from 10,745 in 2000 to 11,827 in 2004 and 14,022 in 2008. It was observed during the post-training follow-up and quarterly supervision visits that morale of the personnel was high.

CONCLUSION

Continuous training and re-training of laboratory personnel on SSM and QA at regular intervals do play an important role for effective and efficient TB control programme.

Microbiological quality and antibiotic residues in informally marketed raw cow milk within the coastal savannah zone of Ghana

OBJECTIVES

To investigate the microbiological quality and the presence of antibiotic residues in raw cow milk and in some indigenous milk products produced and marketed by the informal sector in the coastal savannah zone of Ghana.

METHODS

Milk samples were aseptically collected from 224 kraals and samples of 26 indigenous milk products were purchased from processors and retailers. Total plate counts, total coliform counts and the presence of Escherichia coli and E. coli O157:H7 were determined in all 250 samples. Milk samples were also tested for antibiotic residues.

RESULTS

Total plate counts exceeded 10⁵ CFU/ml in 45.2% of the samples while coliforms exceeded 10³ CFU/ml in 66.0% and E. coli was detected in 11.2%. E. coli was present in raw cow milk but not in the indigenous products and all E. coli isolates were negative for E. coli O157:H7. Antibiotic residues were detected in 3.1% of the raw cow milk samples.

CONCLUSION

Bulk milk contains unacceptable levels of hygiene indicators and antibiotic residues and is a potential source of milk-borne infections. The detection of E. coli and antibiotic residues raises public health concerns about the safety of fresh unpasteurized cow milk in the coastal savannah zone of Ghana and calls for improved farm hygiene, the need for milk pasteurization and the sensible use of antibiotics in the milk industry.

Culture and sensitivity of mycobacterial isolates from cases of pulmonary tuberculosis classified as treatment failures in a teaching hospital

BACKGROUND

The level of drug resistance in mycobacterial isolates from previously treated cases in Ghana is not known although drug resistant tuberculosis threatens efforts to control the disease.

OBJECTIVE

To identify and determine the susceptibility of mycobacterial isolates from tuberculosis cases with clinical treatment failure.

METHODS

This prospective survey was undertaken at the Chest Clinic of Korle Bu Teaching Hospital in Accra, Ghana. The participants were twenty-eight cases referred to the hospital with clinical treatment failure. Two sputum specimens from each case were stained by Ziehl-Neelsen method, cultured, identified and sensitivity tests performed by the proportion method.

RESULTS

Eighteen isolates of mycobacteria were identified from 28 failed treatment cases. Five were atypical mycobacteria. Approximately fifty percent (13/28) of cases had Mycobacterium tuberculosis, 5(18%) had atypical mycobacteria, 7(25%) had pure fungal growth and 3(11% 8) had no growth. Fifteen isolates were resistant to two or more drugs, of which 6 were resistant to all four drugs tested.

CONCLUSION

Continuous drug resistance monitoring must be instituted as part of the tuberculosis control programme.

Situation analysis of TB microscopy centres in Ghana

SETTING

Public health laboratories in Ghana performing tuberculosis (TB) microscopy.

OBJECTIVE

To assess the situation of the laboratories in terms of staff strength, technical skills, documentation, biosafety practices, equipment, supplies and disposal systems.

DESIGN

Methods used for data collection were interviews using a structured questionnaire, informal observation of laboratory registers, disposal systems and safety measures for sputum handling.

RESULTS

Of 114 laboratories visited between 2000 and 2001, 102 (89.5%) were performing TB microscopy. Of the staff working in the laboratories, 9% were medical technologists, 24% laboratory technicians, 37% laboratory assistants and 30% orderlies. Average false-negative and -positive rates were respectively 13% and 14%. Although most of the centres (85.3%) were using the recommended TB laboratory register for recording, in most cases they were not filled in accurately or completely. The majority of the available microscopes had mechanical or optical faults. Availability of other materials for smear preparation and staining ranged from 44% to 82%. The main methods employed for disposal of laboratory waste were burning and burying, but conditions were poor in most of the facilities visited.

CONCLUSION

Training of laboratory personnel in TB microscopy and establishment of a quality assurance system are needed in Ghana.

Improving the laboratory diagnosis of TB in Ghana: the impact of a quality assurance system

SETTING

Greater Accra region, Ghana.

OBJECTIVE

To establish a pilot quality assurance (QA) system in sputum smear microscopy and to evaluate its impact.

DESIGN

Quarterly supporting visits were paid to participating laboratories between 2000 and 2002. Fifteen examined slides were selected randomly from each laboratory during the visits and blindly re-assessed. Feedback was given promptly to the various laboratories. Training and stakeholder workshops were organised whenever necessary.

RESULTS

General improvements in smear preparation and staining as well as the reading ability of the laboratory personnel included in the study were observed. The average marks for specimen quality, staining ability, smear cleanness, thickness, size and evenness increased from 64%, 79%, 69%, 46%, 67% and 60% in the last quarter of 2000 to 81%, 90%, 86%, 79%, 80% and 74%, respectively, 24 months after the establishment of the QA system. Within the same period, the rate of false-positives and -negatives decreased from respectively 14.8% and 20.5% to 0%, and agreements in positivity grade increased from 74% to 95%. The performance of the participating laboratories in keeping the laboratory registers up to date also improved.

CONCLUSION

The QA system needs to be extended to the rest of the country.