Epidemiology of influenza in Nigeria: A secondary analysis of the sentinel surveillance data in Nigeria from 2010 - 2020.

BACKGROUND: Influenza is a leading cause of morbidity and mortality globally. Little is known of the true burden and epidemiology of influenza in Africa. Nigeria has a sentinel surveillance system for influenza virus (IFV). This study seeks to describe the epidemiological characteristics of influenza cases in Nigeria through secondary data analysis of the sentinel surveillance data from 2010 to 2020. METHODOLOGY: A retrospective secondary data analysis of data collected from patients with influenza-like illness (ILI) and severe acute respiratory infection (SARI) in the four Nigeria Influenza Sentinel Surveillance sites from January 2010 to December 2020. Data was cleaned and analyzed using Microsoft Excel and Epi info 7.2 for frequencies and proportions. The results of the analysis were summarized in tables and charts. RESULTS: A total of 13,828 suspected cases of influenza were recorded at the sentinel sites during the study period. About 10.3% (1421/13,828) of these tested positive for IFV of which 1243 (87.5%) were ILI patients, 175 (12.3%) SARI patients, and 3 (0.2%) novel H1N1 patients. Males accounted for 54.2% (770/1421) of the confirmed cases. The median age of confirmed cases was 3 years (range: <1month-97 years). Children 0-4 years accounted for 69.3% (985/1421) of all cases. The predominant subtypes were B lineage not determined (32.3%), A/H1N1 pdm09 (28.8%) and A/H3 (23.0%). There were periods of sustained transmission in most years with 2011 having the highest number of cases. Overall, there were more cases around January to March and August to November. Heart disease and chronic shortness of breath were the most common co-morbidities identified among confirmed cases. CONCLUSION: Influenza remains a significant cause of respiratory illness, especially among children aged less than 4 years. Influenza cases occur all year round with irregular seasonality in Nigeria. Children less than 4 years and those with co-morbidities should be prioritized for vaccination. Vaccine composition in the country should take cognizance of the prevailing strains which are type B (lineage not determined), A/H1N1 pdm09 and A/H3.

Drug-susceptible tuberculosis treatment outcomes and its associated factors among inmates in prison settings in Bauchi State, Nigeria, 2014-2018.

Tuberculosis (TB) is a contagious disease and its transmissibility is increased in congregate settings. TB incidence rates are five-to-fifty times higher among inmates in prison settings than the general population which has a direct impact on the outcome of TB treatment. There is paucity of information on TB treatment outcomes and its associated factors in Nigerian prison settings. We therefore assessed TB treatment outcomes among inmates in prison settings in Bauchi State, Nigeria. We conducted a retrospective data analysis of inmates with TB in the five-main prison settings in Bauchi State. We extracted socio-demographic, clinical and treatment outcome characteristics from TB treatment register of inmates treated for TB between January 2014 and December 2018, using a checklist. We calculated the TB treatment success rate (TSR) and explored the relationship between the TSR and socio-demographic and clinical characteristics. Related variables were modelled in multiple logistic regression to identify factors associated with TSR at 5% level of significance. All 216 inmates were male with mean (SD) age of 37.6±11.4 years. Seventy-six (35.2%) were cured, 61 (28.2%) completed treatment, 65 (30.1%) were transferred-out without evaluation and 14 (6.5%) died. Overall TSR was 72.9%. Factors associated with successful-treatment-outcome were age, weight, imprisonment duration and HIV status. The results indicate that inmates who are 20-29 years are at least ten times more likely to be successful (aOR = 10.5; 95%CI: 3.2-35.1) than inmates who are 55 years or older. Inmates who are 30-39 years are about four times more likely to be successful than inmates who are 55 years or older (aOR = 4.2; 95% CI: 1.3-13.1). In general, the younger an inmate, the more successful he is. Inmates with pretreatment-weight; 55kg or more are 13 times more likely to be successful (aOR = 13.3; 95%CI: 6.0-29.6) than inmates with weight below 55kg. Inmates who were imprisoned for 2 years or less are about three times more likely to be successful (aOR = 2.6; 95%CI: 1.3-5.4) than inmates who were imprisoned for more than 2 years and HIV negative inmates were three times more likely to succeed (aOR = 3.3; 95%CI:1.4-7.8) than inmates who were HIV positive. We recommended that to improve TB treatment outcome among inmates; age, duration-of-imprisonment, weight and TB/HIV co-infection should be the major consideration during pretreatment, psychological and nutritional counselling and a tracking-system be developed by the authority to follow-up inmates transferred-out to other health facilities to ensure they complete the treatment and outcomes evaluated.

Trends in Malaria Cases and Deaths: Assessing National Prevention and Control Progress in Burundi.

BACKGROUND: Malaria is associated with high morbidity and mortality especially in World's tropical regions. In 2016, an estimated 216 million and 445,000 cases of malaria and deaths associated with malaria respectively were reported globally. Malaria is the first leading cause of outpatient visits, hospitalization and death in Burundi. We therefore examined the trend in malaria cases and deaths in Burundi. METHODS: We extracted data from Burundi National Health Information System (BNHIS) and assessed trends in malaria cases and deaths from January 2015 to December 2017. A suspected case of malaria was defined as any person treated by anti-malarial drugs without testing while a confirmed case as any person with a positive microscopy or rapid diagnostic test for malaria parasite. We described malaria cases and deaths, and calculated malaria case incidence rate. RESULTS: A total of22,225,699 malaria cases with 8,660 deaths (CFR 0.04%) was documented during the study period. Out of 22,225,699 cases, 45,291 cases (0.2%) were suspected malaria cases. The observed peak season of malaria infection in any of the studied year was in the raining season (March-June). All provinces of the country were affected. Kirundo and Cankuzo provinces the incidence of malaria cases increased from 10.1 cases per 1,000 persons in 2015 to 13.2 cases per 1,000 persons in 2017. The case fatality rate decreased from 0.06% in 2015 to 0.01% in 2017. CONCLUSION: An increasing trend in malaria prevalence was observed in Burundi but Kirundo and Cankuzo provinces were the most affected. However, the case fatality decreased within the studied period. Malaria intervention should be intensified/scaled up in the raining season and the most affected provinces.

Descriptive epidemiology of measles surveillance data, Osun state, Nigeria, 2016-2018.

BACKGROUND: Globally, an estimate of 254,928 measles cases in 2015 and 89,780 deaths in 2016 occur annually. In Nigeria, measles is the fifth leading causes of under-five child mortality with 342 confirmed cases found in the first 9 epidemic weeks in some states including Osun State. We described the distribution, trend and make projection of measles cases in Osun State. METHODS: The Osun State surveillance weekly reporting data on measles cases from all its 30 Local Government Area (LGA) were reviewed, from January 2016 to December 2018 (n = 1205). Data were analyzed using descriptive statistics and a multiplicative time series model (MTSM). The MTSM was used to determine the trend, seasonality in the data and make projections for 2019 and 2020. RESULTS: Cases of measles were reported across the 30 LGAs of the state between January 2016 and December 2018. The rate of reported cases of measles was 20.2, 34.4 and 28.8 per 100,000 populations in 2016, 2017 and 2018 respectively in Ede south LGA where the highest rates were reported in the 3-year period. Out of the three studied years, year 2017, recorded the highest number of reported cases of measles in Osun State. The trend line for the 3-year period showed a positive correlation (r = + 0.4979, p = 0.056). The computed quarterly variation for the studied years was 1.094 for the 1st quarter, 1.162 for the 2nd quarter, 0.861 for the 3rd quarter and 0.888 for the 4th quarter. A quarterly projection for 2019 and 2020 showed an increasing trend with the second quarter of each year likely to have the highest reported cases of measles. CONCLUSIONS: Ede south LGA has the highest proportion of reported measles cases in Osun State. Measles cases may increase in years ahead, but the second quarter of a year has the highest number. Government should strengthen the existing framework on measles reduction and more attention should be given to the second quarter of each year.

User Evaluation Indicates High Quality of the Surveillance Outbreak Response Management and Analysis System (SORMAS) After Field Deployment in Nigeria in 2015 and 2018.

During the West African Ebola virus disease outbreak in 2014-15, health agencies had severe challenges with case notification and contact tracing. To overcome these, we developed the Surveillance, Outbreak Response Management and Analysis System (SORMAS). The objective of this study was to measure perceived quality of SORMAS and its change over time. We ran a 4-week-pilot and 8-week-implementation of SORMAS among hospital informants in Kano state, Nigeria in 2015 and 2018 respectively. We carried out surveys after the pilot and implementation asking about usefulness and acceptability. We calculated the proportions of users per answer together with their 95% confidence intervals (CI) and compared whether the 2015 response distributions differed from those from 2018. Total of 31 and 74 hospital informants participated in the survey in 2015 and 2018, respectively. In 2018, 94% (CI: 89-100%) of users indicated that the tool was useful, 92% (CI: 86-98%) would recommend SORMAS to colleagues and 18% (CI: 10-28%) had login difficulties. In 2015, the proportions were 74% (CI: 59-90%), 90% (CI: 80-100%), and 87% (CI: 75-99%) respectively. Results indicate high usefulness and acceptability of SORMAS. We recommend mHealth tools to be evaluated to allow repeated measurements and comparisons between different versions and users.

Clinical profile and containment of the Ebola virus disease outbreak in two large West African cities, Nigeria, July-September 2014.

INTRODUCTION: The Ebola virus disease (EVD) outbreak in Nigeria began when an infected diplomat from Liberia arrived in Lagos, the most populous city in Africa, with subsequent transmission to another large city. METHODS: First-, second-, and third-generation contacts were traced, monitored, and classified. Symptomatic contacts were managed at Ebola treatment centers as suspected, probable, and confirmed EVD cases using standard operating procedures adapted from the World Health Organization EVD guidelines. Reverse transcription PCR tests confirmed EVD. Socio-demographic, clinical, hospitalization, and outcome data of the July-September 2014 Nigeria EVD cohort were analyzed. RESULTS: The median age of the 20 EVD cases was 33 years (interquartile range 26-62 years). More females (55%), health workers (65%), and persons <40 years old (60%) were infected than males, non-health workers, and persons aged ≥40 years. No EVD case management worker contracted the disease. Presenting symptoms were fever (85%), fatigue (70%), and diarrhea (65%). Clinical syndromes were gastroenteritis (45%), hemorrhage (30%), and encephalopathy (15%). The case-fatality rate was 40% and there was one mental health complication. The average duration from symptom onset to presentation was 3±2 days among survivors and 5±2 days for non-survivors. The mean duration from symptom onset to discharge was 15±5 days for survivors and 11±2 days for non-survivors. Mortality was higher in the older age group, males, and those presenting late. CONCLUSION: The EVD outbreak in Nigeria was characterized by the severe febrile gastroenteritis syndrome typical of the West African outbreak, better outcomes, rapid containment, and no infection among EVD care-providers. Early case detection, an effective incident management system, and prompt case management with on-site mobilization and training of local professionals were key to the outcome.

Evaluation of the Measles Surveillance System in Kaduna State, Nigeria (2010-2012).

OBJECTIVE: To evaluate the case-based measles surveillance system in Kaduna State of Nigeria and identify gaps in its operation. INTRODUCTION: In Africa, approximately 13 million cases, 650,000 deaths due to measles occur annually, with sub-Saharan Africa having the highest morbidity and mortality. Measles infection is endemic in Nigeria and has been documented to occur all year round, despite high measles routine and supplemental immunization coverage. The frequent outbreaks of measles in Kaduna State prompted the need for the evaluation of the measles case-based surveillance system. METHODS: We interviewed stakeholders and conducted a retrospective record review of the measles case-based surveillance data from 2010 - 2012 and adapted the 2001 CDC guidelines on surveillance evaluation and the Framework for Evaluating Public Health Surveillance Systems for Early Detection of Outbreaks, to assess the systems usefulness, representativeness, timeliness, stability, acceptability and data quality. We calculated the annualized detection rate of measles and non-measles febrile rash, proportion of available results, proportion of LGAs (Districts) that investigated at least one case with blood, proportion of cases that were IgM positive and the incidence of measles. We compared the results with WHO(2004) recommended performance indicators to determine the quality and effectiveness of measles surveillance system. RESULTS: According to the Stakeholders, the case-based surveillance system was useful and acceptable. Median interval between specimen collection and release of result was 7days (1 - 25 days) in 2010, 38 days (Range: 16 - 109 days) in 2011 and 11 days (Range: 1 - 105 days) in 2012. The annualized detection rate of measles rash in 2010 was 2.1 (target: 32), 1.0 (target: 32) in 2011 and 1.4 (target: 32) in 2012. The annualized detection rate of non-measles febrile rash in 2010 was 2.1 (target: 32), 0.6 (target: 32) in 2011 and 0.8 (target: 32) in 2012. Case definitions are simple and understood by all the operators. CONCLUSION: This evaluation showed that the surveillance system was still useful. Also, the efficiency and effectiveness of the laboratory component as captured by the "median interval between specimen collection and the release of results improved in 2010 and 2012 compared to 2011. However, there was a progressive decline in the timeliness and completeness of weekly reports in the years under review.