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Background: Influenza and severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) are both respiratory viruses with similar clinical manifestations and modes of transmission. This study describes influenza data before and during the coronavirus disease pandemic (COVID‐19) in Cameroon and SARS‐CoV‐2 data during the pandemic period. Methods: The study ran from 2017 to 2022, and data were divided into two periods: before (2017–2019) and during (2020–2022) the COVID‐19 pandemic. Nasopharyngeal samples collected from persons with respiratory illness were tested for influenza using the Centers for Disease Control and Prevention (CDC) typing and subtyping assays. During the COVID‐19 pandemic, the respiratory specimens were simultaneously tested for SARS‐CoV‐2 using the DaAn gene protocol or the Abbott real‐time SARS‐CoV‐2 assay. The WHO average curve method was used to compare influenza virus seasonality before and during the pandemic. Results: A total of 6246 samples were tested. Influenza virus detection rates were significantly higher in the pre‐pandemic period compared to the pandemic period (30.8% vs. 15.5%; p < 0.001). Meanwhile, the SARS‐CoV‐2 detection rate was 2.5%. A change in the seasonality of influenza viruses was observed from a bi‐annual peak before the pandemic to no clear seasonal pattern during the pandemic. The age groups 2–4 and 5–14 years were significantly associated with higher influenza positivity rates in both pre‐pandemic and pandemic periods. For SARS‐CoV‐2, all age groups above 15 years were the most affected population. Conclusion: The COVID‐19 pandemic had a significant impact on the seasonal influenza by changing the seasonality of the virus and reducing its detection rates. [ABSTRACT FROM AUTHOR]

Background: Healthcare workers (HWs) are at a high risk of exposure to emerging health threats. Following the first wave of the coronavirus disease 2019 pandemic in Cameroon, we explored the presence and persistence of naturally acquired antibodies against severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and the factors associated with seropositivity in HWs. Methods: Staff at two referral hospitals in Yaoundé or two Health District Hospitals in Obala and Mbalmayo were included in a 6‐month prospective cohort analysis or cross‐sectional survey, respectively. Seroprevalence and associated factors were determined, and Kaplan–Meier curves and Cox proportional hazards models were used to assess antibody persistence or positive seroconversion over time. Results: From August 2020 to March 2021, 426 HWs (median age: 31 years, interquartile range: 27–37 years; 66.4% female) were enrolled. The overall seroprevalence of anti‐SARS‐CoV‐2 antibodies was 54.0% (95% confidence interval [CI]: 49.1–58.8) and was significantly different between study sites (p = 0.04). Of the 216 HWs included in the 6‐month cohort, 109 (50.5%) HWs were seropositive at inclusion; the probability of persistent antibodies or of becoming seropositive was 93.8% (95% CI: 84.2–100) and 78.9% (95% CI: 61.7–88.4), respectively. Seroconversion was associated with study site and occupation but not with infection prevention and control (IPC) practices. Conclusions: We observed high seroprevalence of SARS‐CoV‐2 antibody and seroconversion among HWs associated with occupational risk. This suggests low compliance to the COVID‐19 control measures. Continued training and implementation of IPC measures and accelerated preparedness are needed to better tackle future threats. [ABSTRACT FROM AUTHOR]

Background: Acute lower respiratory tract infections (ALRIs) are one one of the leading causes of morbidity and mortality among people of all ages worldwide, particularly in low‐ and middle‐income countries (LMICs). The purpose of this study was to determine epidemiological characteristics of respiratory viruses in acute respiratory infection (ARI) patients during the COVID‐19 pandemic in Yaoundé, Cameroon. Methods: Patients were monitored for respiratory symptoms as part of the surveillance of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and other respiratory viral infections. Patients of all ages with respiratory symptoms less than 5 days were considered. Sociodemographic and clinical data as well as nasopharyngeal samples was collected from patients. Nasopharyngeal samples were tested for SARS‐CoV‐2, influenza, and respiratory syncytial virus (RSV) using real‐time reverse‐transcription polymerase chain reaction methods. Virus distribution and demographic data were analyzed with R version 2.15.1. Results: From July 2020 to October 2021, 1120 patients were included. The overall viral detection rate was 32.5%, including 9.5% for RSV, 12.6% for influenza virus and 12.8% for SARS‐CoV‐2. Co‐infections were detected in 6.9% of positive cases. While RSV and influenza virus showed seasonal trends, SARS‐CoV‐2 was detected throughout the study period. Conclusion: We found that during COVID‐19 pandemic, respiratory viruses play an important role in etiology of influenza‐like illness in Cameroon, and this observation was true for patients of all ages. [ABSTRACT FROM AUTHOR]

Background: Acute respiratory infections (ARI) are associated with a huge morbidity and mortality worldwide. Rhinoviruses (RVs) and Enteroviruses (EVs) are recognized as leading causes of ARI. Objectives: The present study describes the molecular epidemiology of RVs and EVs in Cameroon over a 3‐year surveillance period. Methods: From September 2011 to October 2014, nasopharyngeal swabs were collected from patients with influenza‐like illness (ILI) and severe acute respiratory infections (SARI). Two sub‐genomic regions of the EVs and RVs were targeted for molecular characterization. These included the most conserved 5′‐untranslated region (5′UTR) and the viral protein 4/viral protein 2 transition region (VP4/VP2). Results: A total of 974 samples were collected. Children ≤5 years accounted for 85.7% (835/974) of all participants. Among them, 160 (16.4%) were positive for RVs and/or EVs. RVs and/or EVs were significantly more identified in ILI compared to SARI patients (P =.015). Both viruses co‐circulated all year long with a marked increase of occurrence during rainy and cold season. All RV species were found to circulate in Cameroon, with 6, 10 and 6 virus types belonging to the RV‐A, RV‐B and RV‐C, respectively. EV species identified comprised EV‐A (1 Coxsackie virus A5), EV‐B (1 Coxsackie virus A9 and 2 Coxsackie virus B1) and EV‐C (1 EV‐C117). Conclusions: This study indicates a strong year‐round occurrence of EV and RV associated respiratory infections in Cameroon. Molecular characterization identified a wide variety of RVs and EVs in patients with ARI in Cameroon. [ABSTRACT FROM AUTHOR]

Background: Influenza surveillance helps time prevention and control interventions especially where complex seasonal patterns exist. We assessed influenza surveillance sustainability in Africa where influenza activity varies and external funds for surveillance have decreased. Methods: We surveyed African Network for Influenza Surveillance and Epidemiology (ANISE) countries about 2011‐2017 surveillance system characteristics. Data were summarized with descriptive statistics and analyzed with univariate and multivariable analyses to quantify sustained or expanded influenza surveillance capacity in Africa. Results: Eighteen (75%) of 24 ANISE members participated in the survey; their cumulative population of 710 751 471 represent 56% of Africa's total population. All 18 countries scored a mean 95% on WHO laboratory quality assurance panels. The number of samples collected from severe acute respiratory infection case‐patients remained consistent between 2011 and 2017 (13 823 vs 13 674 respectively) but decreased by 12% for influenza‐like illness case‐patients (16 210 vs 14 477). Nine (50%) gained capacity to lineage‐type influenza B. The number of countries reporting each week to WHO FluNet increased from 15 (83%) in 2011 to 17 (94%) in 2017. Conclusions: Despite declines in external surveillance funding, ANISE countries gained additional laboratory testing capacity and continued influenza testing and reporting to WHO. These gains represent important achievements toward sustainable surveillance and epidemic/pandemic preparedness. [ABSTRACT FROM AUTHOR]

Background: Rapid reporting of surveillance data is essential to better inform national prevention and control strategies. Objectives: We compare the newly implemented smartphone‐based system to the former paper‐based and short message service (SMS) for collecting influenza epidemiological data in Cameroon. Methods: Of the 13 sites which collect data from persons with influenza‐like illness (ILI), six sites send data through the EWS, while seven sites make use of the paper‐based system and SMS. We used four criteria for the comparison of the data collection tools: completeness, timeliness, conformity and cost. Results: Regarding the different collection tools, data sent by the EWS were significantly more complete (97.6% vs 81.6% vs 44.8%), prompt (74.4% vs n/a vs 60.7%) and of better quality (93.7% vs 76.1% vs 84.0%) than data sent by the paper‐based system and SMS, respectively. The average cost of sending a datum by a sentinel site per week was higher for the forms (5.0 USD) than for the EWS (0.9 USD) and SMS (0.1 USD). The number of outpatient visits and subsequently all surveillance data decreased across the years 2017‐2019 together with the influenza positivity rate from 30.7% to 28.3%. Contrarily, the proportion of influenza‐associated ILI to outpatient load was highest in the year 2019 (0.37 per 100 persons vs 0.28 and 0.26 in the other 2 years). Conclusion: All sentinel sites and even other disease surveillance systems are expected to use this tool in the near term future due to its satisfactory performance and cost. [ABSTRACT FROM AUTHOR]

Background: The International Health Regulations state that early detection and immediate reporting of unusual health events is important for early warning and response systems. Objective: To describe a pilot surveillance program established in health facilities in Yaoundé, Cameroon in 2017 which aimed to enable detection and reporting of public health events. Methods: Cameroon's Ministry of Health, in partnership with the US Centers for Disease Control and Prevention, Cameroon Pasteur Center, and National Public Health Laboratory, implemented event‐based surveillance (EBS) in nine Yaoundé health facilities. Four signals were defined that could indicate possible public health events, and a reporting, triage, and verification system was established among partner organizations. A pre‐defined laboratory algorithm was defined, and a series of workshops trained health facilities, laboratory, and public health staff for surveillance implementation. Results: From May 2017 to January 2018, 30 signals were detected, corresponding to 15 unusual respiratory events. All health facilities reported a signal at least once, and more than three‐quarters of health facilities reported ≥2 times. Among specimens tested, the pathogens detected included Klebsiella pneumoniae, Moraxella catarrhalis, Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus, Pneumocystis jiroveci, influenza A (H1N1) virus, rhinovirus, and adenovirus. Conclusions: The events detected in this pilot were caused by routine respiratory bacteria and viruses, and no novel influenza viruses or other emerging respiratory threats were identified. The surveillance system, however, strengthened relationships and communication linkages between health facilities and public health authorities. Astute clinicians can play a critical role in early detection and EBS is one approach that may enable reporting of emerging outbreaks and public health events. [ABSTRACT FROM AUTHOR]

Background: Several studies have demonstrated the role of meteorological parameters in the seasonality of influenza viruses in tropical and subtropical regions, most importantly temperature, humidity, and rainfall. Objectives: This study aimed to describe the influence of meteorological parameters in the seasonality of influenza viruses in Northern Cameroon, a region characterized by high temperatures. Methods: This was a retrospective study performed in Garoua Cameroon from January 2014 to December 2016. Monthly proportions of confirmed influenza cases from six sentinel sites were considered as dependent variables, whereas monthly values of mean temperature, average relative humidity, and accumulated rainfall were considered as independent variables. A vector error correction model was used to determine the relationship between influenza activity and the meteorological variables. Results and conclusion: Analysis showed that there was a statistically significant association between overall influenza activity and influenza A activity with respect to average relative humidity. A unit increase in humidity within a given month leads to more than 85% rise in the overall influenza and influenza A activity 2 months later. Meanwhile, none of the three meteorological variables could explain influenza B activity. This observation is essential in filling the gap of knowledge and could help in the prevention and control strategies to strengthen influenza surveillance program in Cameroon. [ABSTRACT FROM AUTHOR]

Aim: The epidemiology of human respiratory syncytial virus (HRSV) infection has not yet been systematically investigated in Africa. This systematic review and meta‐analysis are to estimate the prevalence of HRSV infections in people with acute respiratory tract infections (ARTI) in Africa. Method: We searched PubMed, EMBASE, Africa Journal Online, and Global Index Medicus to identify observational studies published from January 1, 2000, to August 1, 2017. We used a random‐effects model to estimate the prevalence across studies. Heterogeneity (I2) was assessed via the chi‐square test on Cochran's Q statistic. Review registration: PROSPERO CRD42017076352. Results: A total of 67 studies (154 000 participants) were included. Sixty (90%), seven (10%), and no studies had low, moderate, and high risk of bias, respectively. The prevalence of HRSV infection varied widely (range 0.4%‐60.4%). The pooled prevalence was 14.6% (95% CI 13.0‐16.4, I2 = 98.8%). The prevalence was higher in children (18.5%; 95% CI 15.8‐21.5) compared to adults (4.0%; 95% CI 2.2‐6.1) and in people with severe respiratory tract infections (17.9%; 95% CI 15.8‐20.1) compared to those with benign forms (9.4%; 95% CI 7.4‐11.5); P‐values <0.0001. The HRSV prevalence was not associated with sex, subregion in Africa, setting, altitude, latitude, longitude, and seasonality. Conclusion: This study suggests a high prevalence of HRSV in people with ARTI in Africa, particularly among children and people with severe clinical form. All innovative strategies to curb the burden should first focus on children which present the highest HRSV‐related burden. [ABSTRACT FROM AUTHOR]

Background Severe acute respiratory illness ( SARI) is recognized as an important cause of morbidity, mortality, and hospitalization among children in developing countries. Little is known, however, in tropical countries like Cameroon about the cause and seasonality of respiratory infections, especially in hospitalized settings. Objectives: Our study investigates the viral etiology and seasonality of SARI in hospitalized children in Yaounde, Cameroon. Methods Prospective clinic surveillance was conducted to identify hospitalized children aged ≤15 years presenting with respiratory symptoms ≤5-day duration. Demographic and clinical data, and respiratory specimens were collected. Nasopharyngeal samples were tested for 17 respiratory viruses using a multiplex polymerase chain reaction. The viral distribution and demographic data were statistically analyzed. Results From September 2011 through September 2013, 347 children aged ≤15 years were enrolled. At least one virus was identified in each of 65·4% children, of which 29·5% were coinfections; 27·3% were positive for human adenovirus ( hAdV), 13·2% for human respiratory syncytial virus ( hRSV), 11·5% for rhinovirus/enterovirus ( RV/ EV), 10·6% for human bocavirus ( hBoV), 9·8% for influenza virus (Inf), 6·6% for human parainfluenza virus ( hPIV), 5·7% for human coronavirus ( hCoV), and 2·3% for human metapneumovirus ( hMPV). While hRSV showed seasonal patterns, hAdV and RV/ EV were detected throughout the year and no evident temporal patterns were observed for the remaining viruses. Conclusion Respiratory viruses were associated with a high burden of hospitalizations among children in Cameroon. Nevertheless, additional studies evaluating asymptomatic Cameroonian children will be important in understanding the relationship between viral carriage and disease. [ABSTRACT FROM AUTHOR]

Introduction Literature on influenza focuses on influenza A, despite influenza B having a large public health impact. The Global Influenza B Study aims to collect information on global epidemiology and burden of disease of influenza B since 2000. Methods Twenty-six countries in the Southern ( n = 5) and Northern ( n = 7) hemispheres and intertropical belt ( n = 14) provided virological and epidemiological data. We calculated the proportion of influenza cases due to type B and Victoria and Yamagata lineages in each country and season; tested the correlation between proportion of influenza B and maximum weekly influenza-like illness ( ILI) rate during the same season; determined the frequency of vaccine mismatches; and described the age distribution of cases by virus type. Results The database included 935 673 influenza cases (2000-2013). Overall median proportion of influenza B was 22·6%, with no statistically significant differences across seasons. During seasons where influenza B was dominant or co-circulated (>20% of total detections), Victoria and Yamagata lineages predominated during 64% and 36% of seasons, respectively, and a vaccine mismatch was observed in ≈25% of seasons. Proportion of influenza B was inversely correlated with maximum ILI rate in the same season in the Northern and (with borderline significance) Southern hemispheres. Patients infected with influenza B were usually younger (5-17 years) than patients infected with influenza A. Conclusion Influenza B is a common disease with some epidemiological differences from influenza A. This should be considered when optimizing control/prevention strategies in different regions and reducing the global burden of disease due to influenza. [ABSTRACT FROM AUTHOR]

The performance of SD Bioline rapid antigen test (RAT) was evaluated using real-time reverse transcription polymerase chain reaction ( rRT-PCR) as gold standard. A total of 718 nasal swabs, including 102 rRT-PCR positive and 616 rRT-PCR negative swabs, were tested. RAT demonstrates a sensitivity of 29·4% with a specificity of 100%. The positivity rate of RAT was highly associated with lower cycle threshold (Ct) values ( P < 0·0001). The excellent specificity of the RAT allowed for the rapid identification of influenza cases. However, negative results should be verified by rRT-PCR test because of limitations observed in sensitivity. [ABSTRACT FROM AUTHOR]