Epidemiology of influenza in West Africa after the 2009 influenza A(H1N1) pandemic, 2010-2012.

BACKGROUND: Over the last decade, capacity for influenza surveillance and research in West Africa has strengthened. Data from these surveillance systems showed influenza A(H1N1)pdm09 circulated in West Africa later than in other regions of the continent. METHODS: We contacted 11 West African countries to collect information about their influenza surveillance systems (number of sites, type of surveillance, sampling strategy, populations sampled, case definitions used, number of specimens collected and number of specimens positive for influenza viruses) for the time period January 2010 through December 2012. RESULTS: Of the 11 countries contacted, 8 responded: Burkina Faso, Cote d'Ivoire, Mali, Mauritania, Niger, Nigeria, Sierra Leone and Togo. Countries used standard World Health Organization (WHO) case definitions for influenza-like illness (ILI) and severe acute respiratory illness (SARI) or slight variations thereof. There were 70 surveillance sites: 26 SARI and 44 ILI. Seven countries conducted SARI surveillance and collected 3114 specimens of which 209 (7%) were positive for influenza viruses. Among influenza-positive SARI patients, 132 (63%) were influenza A [68 influenza A(H1N1)pdm09, 64 influenza A(H3N2)] and 77 (37%) were influenza B. All eight countries conducted ILI surveillance and collected 20,375 specimens, of which 2278 (11%) were positive for influenza viruses. Among influenza-positive ILI patients, 1431 (63%) were influenza A [820 influenza A(H1N1)pdm09, 611 influenza A(H3N2)] and 847 (37%) were influenza B. A majority of SARI and ILI case-patients who tested positive for influenza (72% SARI and 59% ILI) were children aged 0-4 years, as were a majority of those enrolled in surveillance. The seasonality of influenza and the predominant influenza type or subtype varied by country and year. CONCLUSIONS: Influenza A(H1N1)pdm09 continued to circulate in West Africa along with influenza A(H3N2) and influenza B during 2010-2012. Although ILI surveillance systems produced a robust number of samples during the study period, more could be done to strengthen surveillance among hospitalized SARI case-patients. Surveillance systems captured young children but lacked data on adults and the elderly. More data on risk groups for severe influenza in West Africa are needed to help shape influenza prevention and clinical management policies and guidelines.

Global Role and Burden of Influenza in Pediatric Respiratory Hospitalizations, 1982-2012: A Systematic Analysis.

BACKGROUND: The global burden of pediatric severe respiratory illness is substantial, and influenza viruses contribute to this burden. Systematic surveillance and testing for influenza among hospitalized children has expanded globally over the past decade. However, only a fraction of the data has been used to estimate influenza burden. In this analysis, we use surveillance data to provide an estimate of influenza-associated hospitalizations among children worldwide. METHODS AND FINDINGS: We aggregated data from a systematic review (n = 108) and surveillance platforms (n = 37) to calculate a pooled estimate of the proportion of samples collected from children hospitalized with respiratory illnesses and positive for influenza by age group (<6 mo, <1 y, <2 y, <5 y, 5-17 y, and <18 y). We applied this proportion to global estimates of acute lower respiratory infection hospitalizations among children aged <1 y and <5 y, to obtain the number and per capita rate of influenza-associated hospitalizations by geographic region and socio-economic status. Influenza was associated with 10% (95% CI 8%-11%) of respiratory hospitalizations in children <18 y worldwide, ranging from 5% (95% CI 3%-7%) among children <6 mo to 16% (95% CI 14%-20%) among children 5-17 y. On average, we estimated that influenza results in approximately 374,000 (95% CI 264,000 to 539,000) hospitalizations in children <1 y-of which 228,000 (95% CI 150,000 to 344,000) occur in children <6 mo-and 870,000 (95% CI 610,000 to 1,237,000) hospitalizations in children <5 y annually. Influenza-associated hospitalization rates were more than three times higher in developing countries than in industrialized countries (150/100,000 children/year versus 48/100,000). However, differences in hospitalization practices between settings are an important limitation in interpreting these findings. CONCLUSIONS: Influenza is an important contributor to respiratory hospitalizations among young children worldwide. Increasing influenza vaccination coverage among young children and pregnant women could reduce this burden and protect infants <6 mo.

Role of apoptotic protease activating factor-1 in CD4+ depletion during HIV progression.

Objective: This study investigates the role of Apoptotic Protease Activating Factor-1 (APAF-1) in CD4+ cell depletion among human immunodeficiency virus (HIV) patients. Materials and Methods: This is a cross-sectional study in which 105 participants were enrolled, including 60 confirmed HIV-positive patients and 45 HIV-negative controls. HIV-positive patients were further divided based on CD4+ cell counts: Group 1 (<200), Group 2 (200-499), and Group 3 (≥500). An enzyme-linked immunoassay was used to measure APAF-1 levels, and CD4+ T-cell counts were enumerated using a Cyflow counter. Independent student's t-test, Kruskal-Wallis, and Spearman's correlation were utilized as needed. Results: Results showed significant reductions in lymphocytes, platelets, red blood cells, hemoglobin, albumin, and CD4+ cell values among HIV-infected individuals compared to controls. Conversely, APAF-1 and total protein levels were elevated in HIV-positive patients. Among HIV-positive groups, those with CD4+ cell counts <200 exhibited the highest median serum APAF-1 concentration. However, these differences were not statistically significant when compared with the other seropositive groups with CD4+ cell counts between 200 and 499 (P = 0.6726) and CD4+ cell counts of 500 or greater (P = 0.4325). The control group had the lowest median SAPAF-1 concentration, significantly different from HIV-positive groups. Positive correlations were observed between CD4+ counts and lymphocytes, hemoglobin, and hypoalbuminemia, while negative correlations were found between these parameters and APAF-1 levels. Conclusion: APAF-1 is a host factor that potentially contributes to CD4+ cell depletion. Similarly, APAF-1, serum total protein, and albumin levels were found to be predictive of disease progression and could serve as valuable diagnostic biomarkers in the monitoring of HIV/AIDS.

Influenza viruses in Nigeria, 2009-2010: results from the first 17 months of a national influenza sentinel surveillance system.

BACKGROUND: Influenza surveillance data from tropical, sub-Saharan African countries are limited. To better understand the epidemiology of influenza, Nigeria initiated influenza surveillance in 2008. METHODS: Outpatients with influenza-like illness (ILI) and inpatients with severe acute respiratory illness (SARI) were enrolled at 4 sentinel facilities. Epidemiologic data were obtained, and respiratory specimens were tested for influenza viruses, using real-time reverse-transcription polymerase chain reaction assays. RESULTS: During April 2009-August 2010, 2841 patients were enrolled. Of 2803 specimens tested, 217 (7.7%) were positive for influenza viruses (167 [8%] were from subjects with ILI, 17 [5%] were from subjects with SARI, and 33 were from subjects with an unclassified condition). During the prepandemic period, subtype H3N2 (A[H3N2]) was the dominant circulating influenza A virus subtype; 2009 pandemic influenza A virus subtype H1N1 (A[H1N1]pdm09) replaced A(H3N2) as the dominant circulating virus during November 2009. Among persons with ILI, A(H1N1)pdm09 was most frequently found in children aged 5-17 years, whereas among subjects with SARI, it was most frequently found in persons aged ≥ 65 years. The percentage of specimens that tested positive for influenza viruses peaked at 18.9% in February 2010, and the majority were A(H1N1)pdm09. CONCLUSIONS: Influenza viruses cause ILI and SARI in Nigeria. Data from additional years are needed to better understand the epidemiology and seasonality of influenza viruses in Nigeria.

Influenza surveillance in 15 countries in Africa, 2006-2010.

BACKGROUND: In response to the potential threat of an influenza pandemic, several international institutions and governments, in partnership with African countries, invested in the development of epidemiologic and laboratory influenza surveillance capacity in Africa and the African Network of Influenza Surveillance and Epidemiology (ANISE) was formed. METHODS: We used a standardized form to collect information on influenza surveillance system characteristics, the number and percent of influenza-positive patients with influenza-like illness (ILI), or severe acute respiratory infection (SARI) and virologic data from countries participating in ANISE. RESULTS: Between 2006 and 2010, the number of ILI and SARI sites in 15 African countries increased from 21 to 127 and from 2 to 98, respectively. Children 0-4 years accounted for 48% of all ILI and SARI cases of which 22% and 10%, respectively, were positive for influenza. Influenza peaks were generally discernible in North and South Africa. Substantial cocirculation of influenza A and B occurred most years. CONCLUSIONS: Influenza is a major cause of respiratory illness in Africa, especially in children. Further strengthening influenza surveillance, along with conducting special studies on influenza burden, cost of illness, and role of other respiratory pathogens will help detect novel influenza viruses and inform and develop targeted influenza prevention policy decisions in the region.

CD57 expression by T cells in the female genital tract of HIV-zx1 infected women.

Despite an influx of T cells to the cervix during HIV infection, genital T cells are not associated with control of HIV shedding. CD57 expression by T cells has been associated with enhanced migratory potential and CD57+ T cells have been shown to accumulate in tissues during the late stages of HIV disease. We investigated the impact of HIV-infection and clinical status on the expression of CD57 by T cells from the female genital tract in 13 HIV-infected and 5 uninfected women. We found that cervical and blood-derived T cells expressed similar frequencies of CD57. The frequency of CD57 expression by cervical or blood T cells was not associated with clinical status (CD4 counts). No impairment in IFN-gamma production by CD57+ T cells from the genital tract was observed. We conclude that increased T cell senescence does not appear to be a hallmark of genital mucosal HIV-1 infection.

Outbreak of human monkeypox in Nigeria in 2017-18: a clinical and epidemiological report.

BACKGROUND: In September, 2017, human monkeypox re-emerged in Nigeria, 39 years after the last reported case. We aimed to describe the clinical and epidemiological features of the 2017-18 human monkeypox outbreak in Nigeria. METHODS: We reviewed the epidemiological and clinical characteristics of cases of human monkeypox that occurred between Sept 22, 2017, and Sept 16, 2018. Data were collected with a standardised case investigation form, with a case definition of human monkeypox that was based on previously established guidelines. Diagnosis was confirmed by viral identification with real-time PCR and by detection of positive anti-orthopoxvirus IgM antibodies. Whole-genome sequencing was done for seven cases. Haplotype analysis results, genetic distance data, and epidemiological data were used to infer a likely series of events for potential human-to-human transmission of the west African clade of monkeypox virus. FINDINGS: 122 confirmed or probable cases of human monkeypox were recorded in 17 states, including seven deaths (case fatality rate 6%). People infected with monkeypox virus were aged between 2 days and 50 years (median 29 years [IQR 14]), and 84 (69%) were male. All 122 patients had vesiculopustular rash, and fever, pruritus, headache, and lymphadenopathy were also common. The rash affected all parts of the body, with the face being most affected. The distribution of cases and contacts suggested both primary zoonotic and secondary human-to-human transmission. Two cases of health-care-associated infection were recorded. Genomic analysis suggested multiple introductions of the virus and a single introduction along with human-to-human transmission in a prison facility. INTERPRETATION: This study describes the largest documented human outbreak of the west African clade of the monkeypox virus. Our results suggest endemicity of monkeypox virus in Nigeria, with some evidence of human-to-human transmission. Further studies are necessary to explore animal reservoirs and risk factors for transmission of the virus in Nigeria. FUNDING: None.

Meningococcus serogroup C clonal complex ST-10217 outbreak in Zamfara State, Northern Nigeria.

After the successful roll out of MenAfriVac, Nigeria has experienced sequential meningitis outbreaks attributed to meningococcus serogroup C (NmC). Zamfara State in North-western Nigeria recently was at the epicentre of the largest NmC outbreak in the 21st Century with 7,140 suspected meningitis cases and 553 deaths reported between December 2016 and May 2017. The overall attack rate was 155 per 100,000 population and children 5-14 years accounted for 47% (3,369/7,140) of suspected cases. The case fatality rate (CFR) among children 5-9 years was 10%, double that reported among adults ≥ 30 years (5%). NmC and pneumococcus accounted for 94% (172/184) and 5% (9/184) of the laboratory-confirmed cases, respectively. The sequenced NmC belonged to the ST-10217 clonal complex (CC). All serotyped pneumococci were PCV10 serotypes. The emergence of NmC ST-10217 CC outbreaks threatens the public health gains made by MenAfriVac, which calls for an urgent strategic action against meningitis outbreaks.

Evaluation of nine HIV rapid test kits to develop a national HIV testing algorithm in Nigeria.

Background: Non-cold chain-dependent HIV rapid testing has been adopted in many resource-constrained nations as a strategy for reaching out to populations. HIV rapid test kits (RTKs) have the advantage of ease of use, low operational cost and short turnaround times. Before 2005, different RTKs had been used in Nigeria without formal evaluation. Between 2005 and 2007, a study was conducted to formally evaluate a number of RTKs and construct HIV testing algorithms. Objectives: The objectives of this study were to assess and select HIV RTKs and develop national testing algorithms. Method: Nine RTKs were evaluated using 528 well-characterised plasma samples. These comprised 198 HIV-positive specimens (37.5%) and 330 HIV-negative specimens (62.5%), collected nationally. Sensitivity and specificity were calculated with 95% confidence intervals for all nine RTKs singly and for serial and parallel combinations of six RTKs; and relative costs were estimated. Results: Six of the nine RTKs met the selection criteria, including minimum sensitivity and specificity (both ≥ 99.0%) requirements. There were no significant differences in sensitivities or specificities of RTKs in the serial and parallel algorithms, but the cost of RTKs in parallel algorithms was twice that in serial algorithms. Consequently, three serial algorithms, comprising four test kits (BundiTM, DetermineTM, Stat-Pak® and Uni-GoldTM) with 100.0% sensitivity and 99.1% - 100.0% specificity, were recommended and adopted as national interim testing algorithms in 2007. Conclusion: This evaluation provides the first evidence for reliable combinations of RTKs for HIV testing in Nigeria. However, these RTKs need further evaluation in the field (Phase II) to re-validate their performance.

Serum protein electrophoresis under effective control of HIV-1 disease progression.

In this report, we compared the serum protein electrophoresis (SPE) patterns in a subset of HIV-1-infected subjects who did not progress to AIDS without antiretroviral treatment with those in whose control of disease progression was achieved by highly active antiretroviral therapy (HAART). SPE and immunofixation electrophoresis were performed on Helena Electrophoresis System according to manufacturer's instructions. The percentage of SPE abnormalities, resembling chronic inflammation, was significantly higher in HIV-1-infected subject without HAART compared with those under HAART (p = 0.001). The majority of individuals under HAART showed evidence of oligoclonal bands on the γ-band against a polyclonal background compared with those without HAART but ß-γ-band bridging was more evident. Immunofixation pattern was consistent with oligoclonal hypergammaglobulinaemia of IgG kappa type, which was found to be more intense in group without HAART. HIV clinical status did not show appreciable effect on the SPE pattern in subjects without HAART. However, under effective HAART, subjects with better CD4 T-cell count were associated with higher γ-globulin band. In group without HAART, acute infection was found to be associated the higher γ-globulin fraction compared with chronic infection. The opposite was the case under effective HAART. HIV infected subjects that did not progress to AIDS were associated with markedly abnormal SPE pattern. Overall results reflect the host ability compensate defective cellular immunity in HIV-1 infection with humoral immune responses. These findings underscore the usefulness of SPE monitoring HIV disease management and identifying individuals that may not progress to full-blown AIDS in the absence of treatment.

Oxidative indices correlate with dyslipidemia and pro-inflammatory cytokine levels in fluoride-exposed rats.

The aim of this study was to establish the effects of fluoride on lipid metabolism and attendant inflammatory response by exposing rats to 50 mg L(-1) and 100 mg L(-1) of fluoride through drinking water for seven weeks. Both concentrations led to hypercholesterolemia while the 100 mg L(-1) concentration induced hypertriglyceridaemia. High density lipoprotein (HDL) cholesterol levels dropped in the exposed rats while interleukin 2 (IL-2) increased more than 1.5-fold (p<0.05) and IL-6 and plasma TNF-α more than 2.5 fold (p<0.05). Fluoride-exposed rats also had significantly higher levels of liver malondialdehyde (MDA) and plasma lipid hydroperoxide (LOOH) but lower plasma paraoxonase (PON1) activity. Oxidative stress indices correlated with pro-inflammatory cytokines and plasma cholesterol. In contrast, proinflammatory cytokines inversely correlated with plasma triglyceride, HDL cholesterol and PON1. Our results suggest that the association between fluoride exposure with cardiovascular diseases may be related to its ability to disturb lipid homeostasis, and trigger pro-inflammatory cytokines and oxidative stress.

Impaired lipid levels and inflammatory response in rats exposed to cadmium.

To investigate the subchronic effect of cadmium intoxication on lipid metabolism and the inflammatory responses accompanying it, rats were administered 50 and 100 ppm cadmium through their drinking water for 7 weeks. At both concentrations, cadmium exposure resulted in significant elevation (p < 0.05) of total cholesterol and gave rise to hypertriglyceridemia in the plasma of the animals. The proinflammatory cytokines, IL-2, IL-6 and TNF-α, were highly expressed in the animals. At the 50 ppm dose level, plasma IL-2, IL-6 and TNF-α levels were increased by 20 %, 87 % and 336 % respectively, while the 100 ppm dose yielded 32 %, 57 % and 470 % increases, respectively. A drastic build-up of MDA in the liver elicited by the metal led to an 85 % increase in lipid peroxidation at high dose. A 3-fold increase of lipid hydroperoxidation (LOOH) products was obtained on exposure to cadmium at 100 ppm. Cadmium caused more than a 2-fold increase in oxLDL levels at both doses tested. Paraoxonase activity was also significantly repressed, culminating in a 43 % reduction in activity at 100 ppm dose. Disruption of lipid metabolism, increased lipid peroxidation as well as imbalance in proinflammatory cytokine levels may thus, be means by which cadmium induces its toxicity.