Prevalence of non-influenza respiratory viruses in acute respiratory infection cases in Mexico

Change of epidemiological characteristics of four respiratory viral infections in children before and during COVID-19 pandemic

OBJECTIVES

Viruses are the main infectious agents of acute respiratory infections (ARIs) in children. We aim to describe the changes in epidemic characteristics of viral ARIs in outpatient children before and during the COVID-19 pandemic.

PATIENTS AND METHODS

From 2017 to 2022, the results of viral detection in oral pharyngeal swabs in 479,236 children with ARIs in the outpatient department of Children's Hospital, Zhejiang University School of Medicine, were retrospectively analyzed. Viral antigens, including adenovirus (ADV), influenza A (FLUA), influenza B (FLUB) and respiratory syncytial virus (RSV) were detected by the colloidal gold method.

RESULTS

The median age was 3.4 (1.6-5.6) years. Among all the children, 159,895 cases (33.4 %) were positive for at least one virus. The total positive rate for ADV, FLUA and FLUB during the pandemic period was lower than during the pre-pandemic period in every season (pre-pandemic period vs. pandemic period11.7 % vs. 4.7 %, 13.9 % vs. 9.2 %, 7.0 % vs. 5.2 %, respectively, with overall p value < 0.001). However, the positive rate fir RSV was not significantly different between the pre-pandemic period and the pandemic period (5.6 % vs. 5.8 %, p = 0.117). Atypical timing of RSV (summer-autumn 2021) and FLUA (summer 2022) was noted.

CONCLUSIONS

Public health interventions for different pathogens are maximally effective. While positive rates for ADV, FLUA and FLUB decreased during the COVID-19 pandemic period, positive rates for RSV remained similar. In RSV and FLUA, off-season outbreaks were observed. Measures need to be taken to protect children from possible infection surges due to immunity debt having accrued over the last three years.

Understanding the Burden of Respiratory Syncytial Virus in Older Adults in Latin America: An Expert Perspective on Knowledge Gaps

Respiratory syncytial virus (RSV) is a significant global health concern and major cause of hospitalization, particularly among infants and older adults. The clinical impact of RSV is well characterized in infants; however, in many countries, the burden and risk of RSV in older populations are overlooked. In Latin America, there are limited data on RSV epidemiology and disease management in older adults. Therefore, the impact of RSV in this region needs to be addressed. Here, current insights on RSV infections in older populations in Latin America, including those with underlying health conditions, are discussed. We also outline the key challenges limiting our understanding of the burden of RSV in Latin America in a worldwide context and propose an expert consensus to improve our understanding of the burden of RSV in the region. By so doing, we aim to ultimately improve disease management and outcomes of those at risk and to alleviate the impact on healthcare systems.A graphical plain language summary is available with this article.

Prevalence of Influenza Viruses A and B, Adenovirus, Respiratory Syncytial Virus, and Human Metapneumonia Viruses among Children with Acute Respiratory Tract Infection

Background

Acute respiratory tract infection (ARTI) is a significant cause of morbidity and mortality among children worldwide. The majority of acute respiratory infections in children are caused by viruses, with respiratory syncytial virus (RSV) being the most frequently encountered. Other important viral pathogens include human metapneumovirus, human coronaviruses, adenovirus, and influenza. These infections can lead to complications such as bronchitis and pneumonia. So, this study aimed to evaluate the prevalence of influenza viruses A and B, adenovirus, respiratory syncytial virus (RSV), and human metapneumovirus (HMPV) in children with ARTI.

Methods

The molecular diagnostic of polymerase chain reaction approach was used to detect influenza (A and B), metapneumovirus, respiratory syncytial virus (RSV), and adenovirus in respiratory samples of children with acute respiratory infection hospitalization in a teaching hospital of the Shiraz University of Medical Sciences in January 2016-March 2017.

Results

Of the 340 patients examined, 208 (61.20%) were male and the median age was 3.13 ± 2.38 years. Respiratory viruses were found in 179 (52.64%) patients. The male-to-female ratio was 1.63 : 1 in patients who were viral positive. Detection rates for influenza A, adenovirus, influenza B, RSV, and HMPV were 28.23%, 24.70%, 8.52%, 3.23%, and 2.64%, respectively, and coinfections were detected in 24.02%. The most common combination of two-virus coinfections was IFVA/AdV, followed by IFVB/AdV, AdV, IFVB/IFVA, RSV/IFVA, HMPV/AdV, RSV/AdV, and HMPV/IFVA.

Conclusion

The high prevalence of respiratory viruses in children hospitalized with ARTI suggests that viral infection may play a role in disease pathogenesis. This should be confirmed through the conduct of case-control studies and may inform the role of vaccination to prevent respiratory viral infections.

Beyond SARS-CoV-2: epidemiological surveillance of respiratory viruses in Jalisco, Mexico

Introduction

Respiratory viral infections represent a significant global health burden. Historically, influenza, rhinovirus, respiratory syncytial virus, and adenovirus have been the prevalent viruses; however, the landscape shifted with the widespread emergence of SARS-CoV-2. The aim of this study is to present a comprehensive epidemiological analysis of viral respiratory infections in Jalisco, Mexico.

Methods

Data encompassing individuals with flu-like symptoms from July 2021 to February 2023 was scrutinized for viral diagnosis through PCR multiplex. The effect of social mobility on the increase in respiratory viral diagnosis infection was considered to estimate its impact. Additionally, sequences of respiratory viruses stored in public databases were retrieved to ascertain the phylogenetic classification of previously reported viruses in Mexico.

Results

SARS-CoV-2 was the most detected virus (n = 5,703; 92.2%), followed by influenza (n = 479; 7.78%). These viruses were also found as the most common co-infection (n = 11; 50%), and for those with influenza, a higher incidence of severe disease was reported (n = 122; 90.4%; p < 0.001). Regarding comorbidities and unhealthy habits, smoking was found to be a risk factor for influenza infection but a protective factor for SARS-CoV-2 (OR = 2.62; IC 95%: 1.66-4.13; OR = 0.65; IC 95%: 0.45-0.94), respectively. Furthermore, our findings revealed a direct correlation between mobility and the prevalence of influenza infection (0.214; p < 0.001).

Discussion

The study presents evidence of respiratory virus reemergence and prevalence during the social reactivation, facilitating future preventive measures.

Frequency of respiratory virus-associated infection among children and adolescents from a tertiary-care hospital in Mexico City

Acute respiratory infections (ARIs) are a major cause of morbidity and mortality among children. The causative pathogens show geographic and seasonal variations. We retrospectively evaluated the frequency and seasonality of respiratory pathogens in children and adolescents (age: 0-19 years) with ARIs treated between January 1, 2021, and March 31, 2022, at a single center in Mexico. Out of 2400 patients, 1,603 were diagnosed with SARS-CoV-2 infection and 797 were diagnosed with other common respiratory pathogens (CRPs). Of the 797 patients, 632 were infected with one CRP and 165 with > 2 CRPs. Deaths occurred only in SARS-CoV-2-infected patients. Rhinovirus/Enterovirus, respiratory syncytial virus B, and parainfluenza virus 3 were the most prevalent in cases with single and multiple infections. CRP showed a high frequency between autumn and winter of 2021, with higher incidence of hospitalization compared to COVID-19. The main comorbidities were immunosuppression, cardiovascular disease (CD), and asthma. The frequency of CRPs showed a downward trend throughout the first half of 2021. CRPs increased in single- and co-infection cases between the fourth and fifth waves of COVID-19, probably due to decreased nonpharmaceutical interventions and changes in diagnostic tests. Age, cyanosis (symptom), and immunosuppression (comorbidity) were found to differentiate between SARS-CoV-2 infection and CRP infection.

Clinical manifestations of respiratory syncytial virus infection and the risk of wheezing and recurrent wheezing illness: a systematic review and meta-analysis

BACKGROUND

Respiratory syncytial virus (RSV) infection in infants is a global health priority. We aimed to investigate the common manifestations of RSV infection by age group and human development index (HDI) level and to assess its association with the development of wheezing and recurrent wheezing illness.

METHODS

We searched the literature published between January 1, 2010 and June 2, 2022 in seven databases. Outcomes included common manifestations and long-term respiratory outcomes of RSV infection in children. Random- and fixed-effect models were used to estimate the effect size and their 95% confidence intervals. Subgroup analysis was conducted by age and HDI levels. This review was registered in PROSPERO (CRD42022379401).

RESULTS

The meta-analysis included 47 studies. The top five manifestations were cough (92%), nasal congestion (58%), rhinorrhea (53%), shortness of breath (50%), and dyspnea (47%). The clinical symptoms were most severe in infants. In our analysis, compared to very high and high HDI countries, fewer studies in medium HDI countries reported related manifestations, and no study in low HDI countries reported that. The RSV-infected infants were more likely to develop wheezing than the non-infected infants [odds ratio (OR), 3.12; 95% CI, 2.59-3.76] and had a higher risk of developing wheezing illnesses after recovery (OR, 2.60; 95% CI, 2.51-2.70).

CONCLUSIONS

Cough and shortness of breath are common manifestations of RSV infection. More attention should be given to infants and areas with low HDI levels. The current findings confirm an association between RSV infection and wheezing or recurrent wheezing illness.

No Human Respiratory Syncytial Virus but SARS-CoV-2 in children under 5 years old referred to Children Medical Center in 2021, Tehran, Iran

Acute respiratory infections (ARIs) are one of the leading causes of illness and death among community members worldwide. Viral infections are the most common agents estimated to be involved in these patients. This study aimed to investigate the prevalence of human respiratory syncytial virus (hRSV) and severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) among children with ARIs. This study evaluated the presence of SARS‐CoV‐2 and hRSV in 168 throat and nasopharyngeal swab samples using real‐time RT‐PCR. All samples were collected from children under 5 years old with ARIs who attended Children's Medical Center, Tehran, Iran, and sent to the Iranian National Influenza Center with appropriate conditions in 2021. Chi‐square and Fisher's exact tests were used for comparison of the data of the prevalence of hRSV and SARS‐CoV‐2 infections among children. Of 168 patients examined, 95 (57%) were male and 73 (43%) female. Out of them, 47 (28%) cases were younger than 1 year old and 121 cases (72%) were 1–5 years old. The most common clinical manifestations of patients were cough (78%), nausea (31%), diarrhea (27%), and fever (18%). Among 168 patients, no hRSV was detected, while the SARS‐CoV‐2 genome was identified in 16 (9.5%) patients. Among 16 positive cases of SARS‐CoV‐2, 8 (50%) were under 1 year old and 8 positive cases were 1–5 years old. This study was performed at cold months of the year but due to the coronavirus disease 2019 pandemic and adherence to health protocols, school closures, and virtual classes, no cases of hRSV infections were identified.

A pilot study to investigate the risk of SARS-CoV-2 household transmission following hospital discharge of confirmed cases in Vientiane Capital, Lao PDR

Background

Global guidelines from the World Health Organization on discharging patients diagnosed with COVID-19 changed in 2021 to a symptom-based rather than negative PCR-based approach. Studies have shown that shedding of viable virus continues for approximately eight days after symptom onset in most patients. In Vientiane, Laos, until now, patients diagnosed with asymptomatic or mild COVID-19 are hospitalised for 2 weeks and then, if they still test PCR positive for SARS-CoV-2, stay for a further week in a designated quarantine hotel before being discharged home.

Objective

The aim of this pilot study was to investigate the risk of transmission of SARS-CoV-2 to household contacts of discharged patients who are still PCR-positive following 2-3 weeks quarantine in Vientiane, Lao PDR.

Methods

Adult participants, who were resident in Vientiane Capital and who were about to be discharged from hospital (after 2 weeks hospitalisation), or from a quarantine hotel, following a further one-week quarantine, were screened to assess eligibility for the study. The household of each case was visited a maximum of 48 hours before or up to 24 hours after the participant was discharged and a nasopharyngeal swab was taken from all household members. Repeat nasopharyngeal swabs from cases and contacts were taken on day 7 and day 14 after discharge home of each case.

Results

Between 20th May 2021 and 27th August 2021, 55 cases and 84 contacts in 27 households were enrolled in the study. The median [range] age of all 139 included participants was 26.5 years [3 months to 83 years] and 83 (60%) were female. By household, the median [range] number of cases and contacts were 1 [1-6] and 3 [1-13] respectively. At discharge home 32/48 (67%) cases tested positive for SARS-CoV-2. By day 7 11 of 47 cases (23%) still tested positive for SARS-CoV-2 by PCR and by day 14 this number was 2/24 (8%). No contacts tested positive during follow up and the numbers tested at the time of discharge of the case, 7 days later and 2 weeks later were 56, 57 and 37 respectively. Loss to follow up at day 7 and day 14 ranged from 15-50% (participants not at home at the time of visits).

Conclusion

In this pilot study we found no evidence of onward transmission of SARS-CoV-2 to contacts of cases discharged home with a positive PCR result. This suggests the current discharge policy for mild to moderate COVID-19 case following 2 weeks in hospital in the Lao PDR is safe.

Assessment of the Association of COPD and Asthma with In-Hospital Mortality in Patients with COVID-19. A Systematic Review, Meta-Analysis, and Meta-Regression Analysis

Together, chronic obstructive pulmonary disease (COPD) and asthma account for the most common non-infectious respiratory pathologies. Conflicting preliminary studies have shown varied effect for COPD and asthma as prognostic factors for mortality in coronavirus disease 2019 (COVID-19). The aim of this study was to explore the association of COPD and asthma with in-hospital mortality in patients with COVID-19 by systematically reviewing and synthesizing with a meta-analysis the available observational studies. MEDLINE, Scopus, and medRxiv databases were reviewed. A random-effects model meta-analysis was used, and I-square was utilized to assess for heterogeneity. In-hospital mortality was defined as the primary endpoint. Sensitivity and meta-regression analyses were performed. Thirty studies with 21,309 patients were included in this meta-analysis (1465 with COPD and 633 with asthma). Hospitalized COVID-19 patients with COPD had higher risk of death compared to those without COPD (OR: 2.29; 95% CI: 1.79–2.93; I² 59.6%). No significant difference in in-hospital mortality was seen in patients with and without asthma (OR: 0.87; 95% CI: 0.68–1.10; I² 0.0%). The likelihood of death was significantly higher in patients with COPD that were hospitalized with COVID-19 compared to patients without COPD. Further studies are needed to assess whether this association is independent or not. No significant difference was demonstrated in COVID-19-related mortality between patients with and without asthma.

Prevalence of human respiratory syncytial virus, parainfluenza and adenoviruses in East Africa Community partner states of Kenya, Tanzania, and Uganda: A systematic review and meta-analysis (2007-2020)

Background

Viruses are responsible for a large proportion of acute respiratory tract infections (ARTIs). Human influenza, parainfluenza, respiratory-syncytial-virus, and adenoviruses are among the leading cause of ARTIs. Epidemiological evidence of those respiratory viruses is limited in the East Africa Community (EAC) region. This review sought to identify the prevalence of respiratory syncytial virus, parainfluenza, and adenoviruses among cases of ARTI in the EAC from 2007 to 2020.

Methods

A literature search was conducted in Medline, Global Index Medicus, and the grey literature from public health institutions and programs in the EAC. Two independent reviewers performed data extraction. We used a random effects model to pool the prevalence estimate across studies. We assessed heterogeneity with the I² statistic, and Cochran’s Q test, and further we did subgroup analysis. This review was registered with PROSPERO under registration number CRD42018110186.

Results

A total of 12 studies met the eligibility criteria for the studies documented from 2007 to 2020. The overall pooled prevalence of adenoviruses was 13% (95% confidence interval [CI]: 6–21, N = 28829), respiratory syncytial virus 11% (95% CI: 7–15, N = 22627), and parainfluenza was 9% (95% CI: 7–11, N = 28363). Pooled prevalence of reported ARTIs, all ages, and locality varied in the included studies. Studies among participants with severe acute respiratory disease had a higher pooled prevalence of all the three viruses. Considerable heterogeneity was noted overall and in subgroup analysis.

Conclusion

Our findings indicate that human adenoviruses, respiratory syncytial virus and parainfluenza virus are prevalent in Kenya, Tanzania, and Uganda. These three respiratory viruses contribute substantially to ARTIs in the EAC, particularly among those with severe disease and those aged five and above.

Epidemiology of viral respiratory infections in a pediatric reference hospital in Central Panama

Background

Acute respiratory infections (ARIs) are a worldwide public health problem. It is estimated that up to 80% of cases of ARIs are caused by viruses. In Central America, however, we identified few epidemiologic studies on the main ARI-related viruses in hospitalized children.

Methods

This study retrospectively analyzed the clinical charts of patients ages 29 days to 14 years admitted with diagnoses of ARIs in a pediatric reference hospital in central Panama during 2016. The variables analyzed were age, sex, signs, symptoms, and diagnosis at admission. Samples of patients to whom a viral panel was indicated were analyzed via quantitative polymerase chain reaction, qPCR.

Results

The most common virus was respiratory syncytial virus (RSV; 25.9%), followed by influenza A virus (10.6%), rhinovirus (10.6%), parainfluenza type 3 (PIV-3; 8.2%) and adenovirus (5.9%). However, virus detection varied with patient age and season. RSV and Influenza virus were respectively identified mainly during July–November and May–July. All cases of viral co-infection occurred in children < 5-years-old. Both influenza A (H1N1) pdm09 and rhinovirus were detected in all pediatric ages analyzed in this study, unlike RSV and PIV-3, which were only present in children < 5-years-old.

Conclusions

This study analyzed the epidemiological patterns of different respiratory viruses in pediatric patients with ARI from central Panama and found that the prevalence of the specific respiratory viruses identified varied with season and age. The most common viruses were RSV, influenza A, and rhinovirus. There were no reports of human metapneumovirus associated with ARI, which may be explained by the time and geographic location of the study. Knowledge of the local epidemiology of respiratory viruses in tropical countries is helpful in forecasting the peaks of hospitalizations due to ARIs and may help improve prevention efforts aiming at respiratory disease control in these settings.

Epidemiological characteristics of four common respiratory viral infections in children

BACKGROUND

Viruses are the main infectious agents of acute respiratory infections in children. We aim to describe the epidemiological characteristics of viral pathogens of acute respiratory tract infections in outpatient children.

METHODS

From April 2018 to March 2019, the results of viral detection using oral pharyngeal swabs from 103,210 children with acute respiratory tract infection in the outpatient department of the Children's Hospital, Zhejiang University School of Medicine, were retrospectively analyzed. Viral antigens, including adenovirus (ADV), influenza A (FLUA), influenza B (FLUB) and respiratory syncytial virus (RSV), were detected by the colloidal gold method.

RESULTS

At least one virus was detected in 38,355 cases; the positivity rate was 37.2%. A total of 1910 cases of mixed infection with two or more viruses were detected, and the positivity rate of multiple infection was 1.9%. The ADV positivity rate was highest in the 3-6-year-old group (18.7%), the FLUA positivity rate was highest in the > 6-year-old group (21.6%), the FLUB positivity rate was highest in the > 6-year-old group (6.6%), and the RSV positivity rate was highest in the < 1-year-old group (10.6%). There was a significant difference in the positivity rate of viral infection among different age groups (χ² = 1280.7, P < 0.001). The rate of positive viral infection was highest in winter (47.1%). The ADV infection rate was highest in spring (18.2%). The rates of FLUA and FLUB positivity were highest in winter (28.8% and 3.6%, respectively). The rate of RSV positivity was highest in autumn (17.4%). The rate of positive viral infection in different seasons was significantly different (χ² = 6459.1, P < 0.001).

CONCLUSIONS

Viral infection rates in children differ for different ages and seasons. The positivity rate of ADV is highest in the preschool period and that of RSV is highest in infants; that of FLU increases with age. The total positive rate of viral infection in different seasons is highest in winter, as is the rate of FLU positivity.

Analysis of Multiple Factors Involved in Pertussis-Like Coughing

Objectives. To identify risk factors associated with the prognosis of pertussis-like coughing. Methods. A retrospective study on children hospitalized with pertussis-like coughing from 2018 to 2019. We collected all the case data from medical records including age, gender, vaccination, clinical symptoms, complication, pathogens, white blood cell (WBC) count, lymphocyte ratio, application of macrolide antibiotics, usage of sulfamethoxazole, and usage of inhaled glucocorticoids. Logistic regression was used in this study. Results. A total of 213 hospitalized children with pertussis-like coughing were included in this study. About 70 children were cured within 2 weeks. One120 children were cured from 2 weeks to 3 months, including cases of initial attack and relapse. Symptoms lasting longer than 3 months accounts for 10.8%. Bordetella pertussis, WBC count >20 × 10⁹/L and lymphocyte ratio >60% were associated with poor prognosis (P < .05). Conclusions. Bordetella pertussis, WBC count, and lymphocyte ratio are independent risk factors for poor prognosis.

Analysis of influenza data generated by four epidemiological surveillance laboratories in Mexico, 2010-2016

The disease caused by the influenza virus is a global public health problem due to its high rates of morbidity and mortality. Thus, analysis of the information generated by epidemiological surveillance systems has vital importance for health decision making. A retrospective analysis was performed using data generated by the four molecular diagnostic laboratories of the Mexican Social Security Institute between 2010 and 2016. Demographics, influenza positivity, seasonality, treatment choices and vaccination status analyses were performed for the vaccine according to its composition for each season. In all cases, both the different influenza subtypes and different age groups were considered separately. The circulation of A/H1N1pdm09 (48.7%), influenza A/H3N2 (21.1%), influenza B (12.6%), influenza A not subtyped (11%) and influenza A/H1N1 (6.6%) exhibited well-defined annual seasonality between November and March, and there were significant increases in the number of cases every 2 years. An inadequate use of oseltamivir was determined in 38% of cases, and the vaccination status in general varied between 12.1 and 18.5% depending on the season. Our results provide current information about influenza in Mexico and demonstrate the need to update both operational case definitions and medical practice guidelines to reduce the inappropriate use of antibiotics and antivirals.

Association study of genetic polymorphisms in proteins involved in oseltamivir transport, metabolism, and interactions with adverse reactions in Mexican patients with acute respiratory diseases

Oseltamivir, a pro-drug, is the best option for treatment and chemoprophylaxis for influenza outbreaks. However, many patients treated with oseltamivir developed adverse reactions, including hypersensitivity, gastritis, and neurological symptoms. The aim of this study was to determine the adverse drug reactions (ADRs) in Mexican patients treated with oseltamivir and whether these ADRs are associated with SNPs of the genes involved in the metabolism, transport, and interactions of oseltamivir. This study recruited 310 Mexican patients with acute respiratory diseases and treated them with oseltamivir (75 mg/day for 5 days) because they were suspected to have influenza A/H1N1 virus infection. Clinical data were obtained from medical records and interviews. Genotyping was performed using real-time polymerase chain reaction and TaqMan probes. The association was assessed under genetic models with contingency tables and logistic regression analysis. Out of 310 patients, only 38 (12.25%) presented ADRs to oseltamivir: hypersensitivity (1.9%), gastritis (10%), and depression and anxiety (0.9%). The polymorphism ABCB1-rs1045642 was associated with adverse drug reactions under the recessive model (P = 0.017); allele C was associated with no adverse drug reactions, while allele T was associated with adverse drug reactions. The polymorphisms SLC15A1-rs2297322, ABCB1-rs2032582, and CES1-rs2307243 were not consistent with Hardy-Weinberg equilibrium, and no other associations were found for the remaining polymorphisms. In conclusion, the polymorphism rs1045642 in the transporter encoded by the ABCB1 gene is a potential predictive biomarker of ADRs in oseltamivir treatment.

Systematic review on respiratory syncytial virus epidemiology in adults and the elderly in Latin America

OBJECTIVES

The present study provides a comprehensive review of the recently published data on RSV epidemiology in adults and the elderly in Latin America.

METHODS

A systematic literature search was carried out in Medline, Scielo, Lilacs, and Cochrane Library. The search strategy aimed at retrieving studies focusing on RSV prevalence, burden, risk factors, and the routine clinical practice in the prevention and management of RSV infections in Latin American countries. Only articles published between January 2011 and December 2017 were considered.

RESULTS

Eighteen studies were included. Percentages of RSV detection varied highly across included studies for adult subjects with respiratory infections (0% to 77.9%), influenza-like illness (1.0% to 16.4%) and community-acquired pneumonia (1.3% to 13.5%). Considerable percentages of hospitalization were reported for RSV-infected adults with influenza-like illness (40.9% and 69.9%) and community-acquired pneumonia (91.7%).

CONCLUSIONS

Recent RSV data regarding adult populations in Latin America are scarce. RSV was documented as a cause of illness in adults and the elderly, being identified in patients with acute respiratory infections, influenza-like illness and community-acquired pneumonia. The studies suggest that RSV infections may be a significant cause of hospitalization in adult populations in Latin America, including younger adults.

Severe Acute Respiratory Infections With Influenza and Noninfluenza Respiratory Viruses: Yemen, 2011-2016

In 2010, Yemen started the surveillance for severe acute respiratory infections (SARIs) by establishing 2 sentinel sites in Sana’a and Aden city. This study aims to determine the proportions of influenza and noninfluenza viruses among SARI patients and to determine the severity of SARI and its associated factors. The data of SARI patients who were admitted to SARI surveillance sites at Al Johory hospital in Sana’a and Al Wahdah hospital in Aden city during the period 2011-2016 were analyzed. The proportions of positive influenza viruses (type A, B) and noninfluenza viruses (respiratory syncytial, adenovirus, human parainfluenza, and human metapneumovirus), intensive care unit (ICU) admission rate, and fatality rate among SARI patients were calculated. A total of 1811 of SARI patients were admitted during 2011-2016. Of those, 78% were <15 years old. A total of 89 (5%) patients had influenza viruses and 655 (36%) had noninfluenza viruses. The overall ICU admission rate was 40% and the case-fatality rate was 8%. Infection by influenza type (A, B) and mixed (adenovirus, human parainfluenza) was significantly associated with lower ICU admission. Age <15 years old, infection with influenza B, pre-existence of chronic diseases, and admission to Aden site were significantly associated with higher fatality rate among patients. In conclusion; SARI patients in Yemen had a high ICU admission and case-fatality rates. Influenza type B, chronic diseases, and admission to Aden site are associated with higher fatality rate. Expanding surveillance sites and panel of laboratory tests to involve other pathogens will help to provide accurate diagnosis for SARI etiology and give more comprehensive picture. Training staff for SARI case management will help to reduce severe outcomes.

Identfication of viral and bacterial etiologic agents of the pertussis-like syndrome in children under 5 years old hospitalized

BACKGROUND

Acute respiratory infections (ARIs) represent an important cause of morbidity and mortality in children, remaining a major public health concern, especially affecting children under 5 years old from low-income countries. Unfortunately, information regarding their epidemiology is still limited in Peru.

METHODS

A secondary data analysis was performed from a previous cross-sectional study conducted in children with a probable diagnosis of Pertussis from January 2010 to July 2012. All samples were analyzed via Polymerase Chain Reaction (PCR) for the following etiologies: Influenza-A, Influenza-B, RSV-A, RSV-B, Adenovirus, Parainfluenza 1 virus, Parainfluenza 2 virus, Parainfluenza 3 virus, Mycoplasma pneumoniae and Chlamydia pneumoniae.

RESULTS

A total of 288 patients were included. The most common pathogen isolated was Adenovirus (49%), followed by Bordetella pertussis (41%) from our previous investigation, the most prevelant microorganisms were Mycoplasma pneumonia (26%) and Influenza-B (19.8%). Coinfections were reported in 58% of samples and the most common association was found between B. pertussis and Adenovirus (12.2%).

CONCLUSIONS

There was a high prevalence of Adenovirus, Mycoplasma pneumoniae and other etiologies in patients with a probable diagnosis of pertussis. Despite the presence of persistent cough lasting at least two weeks and other clinical characteristics highly suspicious of pertussis, secondary etiologies should be considered in children under 5 years-old in order to give a proper treatment.

"Differential risk of hospitalization among single virus infections causing influenza-like illnesses"

BACKGROUND

Acute respiratory infections are a major cause of morbidity in children and are often caused by viruses. However, the relative severity of illness associated with different viruses is unclear. The objective of this study was to evaluate the risk of hospitalization from different viruses in children presenting with an influenza-like illness (ILI).

METHODS

Data from children 5 years old or younger participating in an ILI natural history study from April 2010 to March 2014 was analyzed. The adjusted odds ratio for hospitalization was estimated in children with infections caused by respiratory syncytial virus (RSV), metapneumovirus, bocavirus, parainfluenza viruses, rhinovirus/enterovirus, coronavirus, adenovirus, and influenza.

RESULTS

A total of 1486 children (408 outpatients and 1078 inpatients) were included in this analysis. At least one virus was detected in 1227 (82.6%) patients. The most frequent viruses detected as single pathogens were RSV (n = 286), rhinovirus/enterovirus (n = 251), parainfluenza viruses (n = 104), and influenza A or B (n = 99). After controlling for potential confounders (age, sex, recruitment site, days from symptom onset to enrollment, and underlying illnesses), children with RSV and metapneumovirus infections showed a greater likelihood of hospitalization than those infected by parainfluenza viruses (OR 2.7 and 1.9, respectively), rhinovirus/enterovirus (OR 3.1 and 2.1, respectively), coronaviruses (OR 4.9 and 3.4, respectively), adenovirus (OR 4.6 and 3.2, respectively), and influenza (OR 6.3 and 4.4, respectively).

CONCLUSIONS

Children presenting with ILI caused by RSV and metapneumovirus were at greatest risk for hospitalization, while children with rhinovirus/enterovirus, parainfluenza, coronavirus, adenovirus, and influenza were at lower risk of hospitalization.

The epidemiology and severity of respiratory viral infections in a tropical country: Ecuador, 2009-2016

BACKGROUND

Respiratory viral infections (RVI) are a leading cause of mortality worldwide. We compared the epidemiology and severity of RVI in Ecuador during 2009-2016.

METHODS

Respiratory specimens collected within the national surveillance system were tested for influenza viruses, respiratory syncytial virus (RSV), adenovirus, parainfluenza virus, and human metapneumovirus. Overall and virus-specific positive detection rate (PDR) were calculated and compared the timing of epidemics caused by the different viruses. Logistic regression models were used to compare the age distribution and risk of death across respiratory viruses.

RESULTS

A total of 41,172 specimens were analyzed: influenza (PDR=14.3%) and respiratory syncytial virus (RSV) (PDR=9.5%) were the most frequently detected viruses. Influenza epidemics typically peaked in December-January and RSV epidemics in March; seasonality was less evident for the other viruses. Compared to adults, children were more frequently infected with RSV, adenovirus, parainfluenza, and influenza B, while the elderly were less frequently infected with influenza A(H1N1)p. The age-adjusted risk of death was highest for A(H1N1)p (odds ratio [OR] 1.73, 95% confidence intervals [CI] 1.38-2.17), and lowest for RSV (OR 0.75, 95%CI 0.57-0.98).

CONCLUSIONS

Whilst influenza and RSV were the most frequently detected pathogens, the risk of death differed by RVI, being highest for pandemic influenza and lowest for RSV.

Regional, age and respiratory-secretion-specific prevalence of respiratory viruses associated with asthma exacerbation: a literature review

Despite increased understanding of how viral infection is involved in asthma exacerbations, it is less clear which viruses are involved and to what extent they contribute to asthma exacerbations. Here, we sought to determine the prevalence of different respiratory viruses during asthma exacerbations. Systematic computerized searches of the literature up to June 2017 without language limitation were performed. The primary focus was on the prevalence of respiratory viruses, including AdV (adenovirus), BoV (bocavirus), CoV (coronavirus), CMV (cytomegalovirus), EnV (enterovirus), HSV (herpes simplex virus), IfV (influenza virus), MpV (metapneumovirus), PiV (parainfluenzavirus), RV (rhinovirus) and RSV (respiratory syncytial virus) during asthma exacerbations. We also examined the prevalence of viral infection stratified by age, geographic region, type of respiratory secretion, and detection method. Sixty articles were included in the final analysis. During asthma exacerbations, the mean prevalence of AdV, BoV, CoV, CMV, EnV, HSV, IfV, MpV, PiV, RV and RSV was 3.8%, 6.9%, 8.4%, 7.2%, 10.1%, 12.3%, 10.0%, 5.3%, 5.6%, 42.1% and 13.6%, respectively. EnV, MPV, RV and RSV were more prevalent in children, whereas AdV, BoV, CoV, IfV and PiV were more frequently present in adults. RV was the major virus detected globally, except in Africa. RV could be detected in both the upper and lower airway. Polymerase chain reaction was the most sensitive method for detecting viral infection. Our findings indicate the need to develop prophylactic polyvalent or polyvirus (including RV, EnV, IfV and RSV) vaccines that produce herd immunity and reduce the healthcare burden associated with virus-induced asthma exacerbations.