The impact of sub-national heterogeneities in demography and epidemiology on the introduction of rubella vaccination programs in Nigeria.

Rubella infection during pregnancy can result in miscarriage or infants with a constellation of birth defects known as congenital rubella syndrome (CRS). When coverage is inadequate, rubella vaccination can increase CRS cases by increasing the average age of infection. Thus, the World Health Organisation recommends that countries introducing rubella vaccine be able to vaccinate at least 80% of each birth cohort. Previous studies have focused on national-level analyses and have overlooked sub-national variation in introduction risk. We characterised the sub-national heterogeneity in rubella transmission within Nigeria and modelled local rubella vaccine introduction under different scenarios to refine the set of conditions and strategies required for safe rubella vaccine use. Across Nigeria, the basic reproduction number ranged from 2.6 to 6.2. Consequently, the conditions for safe vaccination varied across states with low-risk areas requiring coverage levels well below 80 %. In high-risk settings, inadequate routine coverage needed to be supplemented by campaigns that allowed for gradual improvements in vaccination coverage over time. Understanding local heterogeneities in both short-term and long-term epidemic dynamics can permit earlier nationwide introduction of rubella vaccination and identify sub-national areas suitable for program monitoring, program improvement and campaign support.

Epidemiological description of and response to a large yellow fever outbreak in Edo state Nigeria, September 2018 - January 2019.

BACKGROUND: Edo State Surveillance Unit observed the emergence of a disease with "no clear-cut-diagnosis", which affected peri-urban Local Government Areas (LGAs) from September 6 to November 1, 2018. On notification, the Nigeria Centre for Disease Control deployed a Rapid Response Team (RRT) to support outbreak investigation and response activities in the State. This study describes the epidemiology of and response to a large yellow fever (YF) outbreak in Edo State. METHODS: A cross-sectional descriptive outbreak investigation of YF outbreak in Edo State. A suspected case of YF was defined as "Any person residing in Edo State with acute onset of fever and jaundice appearing within 14 days of onset of the first symptoms from September 2018 to January 2019". Our response involved active case search in health facilities and communities, retrospective review of patients' records, rapid risk assessment, entomological survey, rapid YF vaccination coverage assessment, blood sample collection, case management and risk communication. Descriptive data analysis using percentages, proportions, frequencies were made. RESULTS: A total of 209 suspected cases were line-listed. Sixty-seven (67) confirmed in 12 LGAs with 15 deaths [Case fatality rate (CFR 22.4%)]. Among confirmed cases, median age was 24.8, (range 64 (1-64) years; Fifty-one (76.1%) were males; and only 13 (19.4%) had a history of YF vaccination. Vaccination coverage survey involving 241 children revealed low YF vaccine uptake, with 44.6% providing routine immunisation cards for sighting. Risk of YF transmission was 71.4%. Presence of Aedes with high-larval indices (House Index ≥5% and/or Breteau Index ≥20) were established in all the seven locations visited. YF reactive mass vaccination campaign was implemented. CONCLUSION: Edo State is one of the states in Nigeria with the highest burden of yellow fever. More males were affected among the confirmed. Major symptoms include fever, jaundice, weakness, and bleeding. Majority of surveillance performance indicators were above target. There is a high risk of transmission of the disease in the state. Low yellow fever vaccination coverage, and presence of yellow fever vectors (Ae.aegypti, Ae.albopictus and Ae.simpsoni) are responsible for cases in affected communities. Enhanced surveillance, improved laboratory sample management, reactive vaccination campaign, improved yellow fever case management and increased risk communication/awareness are very important mitigation strategies to be sustained in Edo state to prevent further spread and mortality from yellow fever.

Predictors of tuberculosis treatment success among HIV-TB co-infected patients attending major tuberculosis treatment sites in Abeokuta, Ogun State, Nigeria.

INTRODUCTION: tuberculosis (TB) is the commonest opportunistic infection and cause of death in patients with Human Immunodeficiency Virus (HIV) in developing countries. World Health Organization (WHO) recommends 85% treatment success rate for all TB cases as an indicator of TB control. The study aimed at determining TB treatment success rate among TB-HIV co-infected patients and identifying predictors of successful treatment among patients in TB treatment sites in Abeokuta, Nigeria. METHODS: it was a cross-sectional study among HIV-TB co-infected patients in the two major health facilities in Abeokuta, Nigeria. Socio-demographic characteristics with treatment history were obtained using a semi-structured questionnaire. Sputum samples were collected and tested for acid-fast bacilli (AFB) using a standard method according to national guideline for TB treatment to determine treatment success rate. Treatment success was defined as any HIV positive patient with a diagnosis of TB by acid-fast bacilli (AFB) smear positivity at diagnosis, who after 6 months of complete treatment becomes smear negative. Adjusted odds ratio was used to identify independent predictors of successful treatment outcome with confidence interval set at 95% and level of significance set at P < 0.05. RESULTS: a total of 109 HIV-TB co-infected patients were enrolled for this study. Fifty-nine (54.1%) were females, 106 (97.3%) were newly treated for TB. Eighty-five (78.0%) were treated in a private health facility. A total of 91 had successful treatment outcome with a treatment success rate (TSR) of 83.5%. Eleven (10.1%) died, 5 (4.6%) defaulted, 1 (0.9%) failed treatment, 1 (0.9%) was transferred out. Successful treatment was associated with being newly registered (i.e. receiving TB treatment under the DOTS program for the first time), receiving TB treatment for the first time (adjusted OR = 18, 95%CI: 1.5-482.3) and being treated at a private health facility (adjusted OR = 14.1, 95%CI 4.27-48.4). CONCLUSION: treatment success rate of TB among HIV-TB co-infected patients in this study slightly falls below the WHO target. Registration status and health facility type were predictors of treatment outcome among study patients. Patients and healthcare workers in public facilities were educated on HIV-TB co-infection management.