Influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus are the most common viruses associated with acute lower respiratory infections in young children (<5 years) and ...older people (≥65 years). A global report of the monthly activity of these viruses is needed to inform public health strategies and programmes for their control.
In this systematic analysis, we compiled data from a systematic literature review of studies published between Jan 1, 2000, and Dec 31, 2017; online datasets; and unpublished research data. Studies were eligible for inclusion if they reported laboratory-confirmed incidence data of human infection of influenza virus, respiratory syncytial virus, parainfluenza virus, or metapneumovirus, or a combination of these, for at least 12 consecutive months (or 52 weeks equivalent); stable testing practice throughout all years reported; virus results among residents in well-defined geographical locations; and aggregated virus results at least on a monthly basis. Data were extracted through a three-stage process, from which we calculated monthly annual average percentage (AAP) as the relative strength of virus activity. We defined duration of epidemics as the minimum number of months to account for 75% of annual positive samples, with each component month defined as an epidemic month. Furthermore, we modelled monthly AAP of influenza virus and respiratory syncytial virus using site-specific temperature and relative humidity for the prediction of local average epidemic months. We also predicted global epidemic months of influenza virus and respiratory syncytial virus on a 5° by 5° grid. The systematic review in this study is registered with PROSPERO, number CRD42018091628.
We initally identified 37 335 eligible studies. Of 21 065 studies remaining after exclusion of duplicates, 1081 full-text articles were assessed for eligibility, of which 185 were identified as eligible. We included 246 sites for influenza virus, 183 sites for respiratory syncytial virus, 83 sites for parainfluenza virus, and 65 sites for metapneumovirus. Influenza virus had clear seasonal epidemics in winter months in most temperate sites but timing of epidemics was more variable and less seasonal with decreasing distance from the equator. Unlike influenza virus, respiratory syncytial virus had clear seasonal epidemics in both temperate and tropical regions, starting in late summer months in the tropics of each hemisphere, reaching most temperate sites in winter months. In most temperate sites, influenza virus epidemics occurred later than respiratory syncytial virus (by 0·3 months 95% CI −0·3 to 0·9) while no clear temporal order was observed in the tropics. Parainfluenza virus epidemics were found mostly in spring and early summer months in each hemisphere. Metapneumovirus epidemics occurred in late winter and spring in most temperate sites but the timing of epidemics was more diverse in the tropics. Influenza virus epidemics had shorter duration (3·8 months 3·6 to 4·0) in temperate sites and longer duration (5·2 months 4·9 to 5·5) in the tropics. Duration of epidemics was similar across all sites for respiratory syncytial virus (4·6 months 4·3 to 4·8), as it was for metapneumovirus (4·8 months 4·4 to 5·1). By comparison, parainfluenza virus had longer duration of epidemics (6·3 months 6·0 to 6·7). Our model had good predictability in the average epidemic months of influenza virus in temperate regions and respiratory syncytial virus in both temperate and tropical regions. Through leave-one-out cross validation, the overall prediction error in the onset of epidemics was within 1 month (influenza virus −0·2 months −0·6 to 0·1; respiratory syncytial virus 0·1 months −0·2 to 0·4).
This study is the first to provide global representations of month-by-month activity of influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus. Our model is helpful in predicting the local onset month of influenza virus and respiratory syncytial virus epidemics. The seasonality information has important implications for health services planning, the timing of respiratory syncytial virus passive prophylaxis, and the strategy of influenza virus and future respiratory syncytial virus vaccination.
European Union Innovative Medicines Initiative Respiratory Syncytial Virus Consortium in Europe (RESCEU).
•Human sapoviruses cause epidemic and sporadic acute gastroenteritis globally (n = 79).•Typing methods were designed based on a limited number of sapovirus sequences (n = 80).•Success rate typing is ...suboptimal due to viral evolution (n = 59).•We report 68 new near-complete genome sequences of all human sapovirus genogroups (n = 84).•New sequences show several discrepancies with primer binding sites (n = 69).
Sapoviruses are responsible for sporadic and epidemic acute gastroenteritis worldwide. Sapovirus typing protocols have a success rate as low as 43% and relatively few complete sapovirus genome sequences are available to improve current typing protocols.
To increase the number of complete sapovirus genomes to better understand the molecular epidemiology of human sapovirus and to improve the success rate of current sapovirus typing methods, we used deep metagenomics shotgun sequencing to obtain the complete genomes of 68 sapovirus samples from four different countries across the Americas (Guatemala, Nicaragua, Peru and the US).
VP1 genotyping showed that all sapovirus sequences could be grouped in the four established genogroups (GI (n = 13), GII (n = 30), GIV (n = 23), GV (n = 2)) that infect humans. They include the near-complete genome of a GI.6 virus and a recently reported novel GII.8 virus. Sequences of the complete RNA-dependent RNA polymerase gene could be grouped into three major genetic clusters or polymerase (P) types (GI.P, GII.P and GV.P) with all GIV viruses harboring a GII polymerase. One (GII.P-GII.4) of the new 68 sequences was a recombinant virus with the hotspot between the NS7 and VP1 regions.
Analyses of this expanded database of near-complete sapovirus sequences showed several mismatches in the genotyping primers, suggesting opportunities to revisit and update current sapovirus typing methods.
•We validated genogroup-specific one-step conventional RT-PCR assays (PC assays) for sequence-based dual typing of GI and GII norovirus strains.•The PC assays use a combination of oligonucleotide ...primers that target a genomic region spanning the 3’-end of ORF1 and 5’end of ORF2 of GI and GII noroviruses.•The PC assays are sensitive (5 to 50 copies/rx) and detect all currently identified norovirus P-types and capsid genotypes from different geographic regions.•The PC assays have been successfully implemented by CaliciNet USA and CaliciNet China.
Noroviruses are the major cause of acute gastroenteritis (AGE) in people of all ages globally. Standardized genotyping is key for outbreak investigations and surveillance networks.
Here we describe the validation of a one-step conventional RT-PCR assay for sequence-based dual typing of GI and GII noroviruses.
This polymerase (P) and capsid (C) dual typing assay uses a combination of previously published oligonucleotide primers amplifying a genomic region spanning the 3'-end of ORF1 and 5'end of ORF2 resulting in a 579 bp product for GI and 570 bp product for GII viruses.
The limit of detection of the assay ranged from 5 to 50 copies of viral RNA per reaction for GI and GII. To validate the assay, we tested 2,663 noroviruspositive stool samples from outbreaks and sporadic cases of AGE in Bangladesh, Guatemala, Peru, and USA collected between 2010–2019, of which 2,392 (90 %) were genotyped successfully. Most of the known genotypes infecting humans (GI (n = 9) and GII (n = 23)) and P types (GI (n = 15), GII, (n = 20)) could be detected. The remaining 270 samples had low viral load (Ct > 30) by real-time RT-PCR. A panel of 166 samples positive for other enteric viruses (rotavirus, astrovirus, sapovirus, adenovirus type 40/41) tested negative.
The use of broadly reactive genotyping assays greatly strengthens exchange of standardized genotype data globally to monitor trends in genotype diversity which is important for both the development of vaccines and to measure their impact.
Acute respiratory infection (ARI) is an important cause of mortality in children and adults. However, studies assessing risk factors for ARI-related deaths in low- and middle-income settings are ...limited. We describe ARI-related death and associated factors among children aged < 2 years and adults aged ≥18 years hospitalized with ARI in Guatemala.
We used respiratory illness surveillance data in Guatemala from 2007 to 2013. ARI was defined as evidence of acute infection and ≥ 1 sign/symptom of respiratory disease in hospitalized patients. Clinical, sociodemographic, and follow-up data were gathered. Nasopharyngeal/oropharyngeal swabs were collected from patients with ARI and tested for 6 respiratory viruses; urine was collected only from adults with ARI and tested for pneumococcal antigen. Blood cultures and chest radiographs were performed at the physician's discretion. Radiographs were interpreted per World Health Organization guidelines to classify endpoint pneumonia (i.e. suggestive of bacterial pneumonia). Multivariable logistic regression was used to compare characteristics of patients with fatal cases, including those who died in-hospital or were discharged in a moribund state, with those of patients with non-fatal cases.
Among 4109 ARI cases identified in hospitalized children < 2 years old, 174 (4%) were fatal. Median age at admission was 4 and 6 months for children with fatal and non-fatal cases, respectively. Factors associated with fatality included low weight-for-age, low family income, heart disease, and endpoint pneumonia; breastfeeding and respiratory syncytial virus (RSV) detection were negatively associated with fatality. Among 1517 ARI cases identified in hospitalized adults ≥18 years, 181 (12%) episodes were fatal. Median age at admission was 57 years for adults with fatal and non-fatal cases. Low body mass index, male sex, kidney disease, and endpoint pneumonia were significantly more common among patients with fatal versus non-fatal cases.
Our findings highlight some of the factors that must be addressed in order to reduce ARI-related mortality, including promotion of good nutrition, breastfeeding, management and prevention of chronic comorbidities, and poverty reduction. Although no specific pathogen increased risk for death, endpoint pneumonia was significantly associated with fatality, suggesting that the pneumococcal conjugate vaccine could contribute to future reductions in ARI-related mortality.
Acute respiratory infections (ARI) are an important cause of illness and death worldwide, yet data on the etiology of ARI and the population-level burden in developing countries are limited. ...Surveillance for ARI was conducted at two hospitals in Guatemala. Patients admitted with at least one sign of acute infection and one sign or symptom of respiratory illness met the criteria for a case of hospitalized ARI. Nasopharyngeal/oropharyngeal swabs were collected and tested by polymerase chain reaction for adenovirus, parainfluenza virus types 1,2 and 3, respiratory syncytial virus, influenza A and B viruses, human metapneumovirus, Chlamydia pneumioniae, and Mycoplasma pneumoniae. Urine specimens were tested for Streptococcus pneumoniae antigen. Blood culture and chest radiograph were done at the discretion of the treating physician. Between November 2007 and December 2011, 3,964 case-patients were enrolled. While cases occurred among all age groups, 2,396 (60.4%) cases occurred in children <5 years old and 463 (11.7%) among adults ≥65 years old. Viruses were found in 52.6% of all case-patients and 71.8% of those aged <1 year old; the most frequently detected was respiratory syncytial virus, affecting 26.4% of case-patients. Urine antigen testing for Streptococcus pneumoniae performed for case-patients ≥15 years old was positive in 15.1% of those tested. Among 2,364 (59.6%) of case-patients with a radiograph, 907 (40.0%) had findings suggestive of bacterial pneumonia. Overall, 230 (5.9%) case-patients died during the hospitalization. Using population denominators, the observed hospitalized ARI incidence was 128 cases per 100,000, with the highest rates seen among children <1 year old (1,703 per 100,000), followed by adults ≥65 years old (292 per 100,000). These data, which demonstrate a substantial burden of hospitalized ARI in Guatemala due to a variety of pathogens, can help guide public health policies aimed at reducing the burden of illness and death due to respiratory infections.
Widespread availability of antibiotics without prescription potentially facilitates overuse and contributes to selection pressure for antimicrobial resistant bacteria. Prior to this study, anecdotal ...observations in Guatemala identified corner stores as primary antibiotic dispensaries, where people purchase antibiotics without prescriptions. We carried out a cross sectional study to document the number and types of antibiotics available in corner stores, in four study areas in Guatemala. A total of 443 corner stores were surveyed, of which 295 (67%) sold antibiotics. The most commonly available antibiotics were amoxicillin, found in 246/295 (83%) stores, and tetracycline, found in 195/295 (66%) stores. Over the counter sales result from laissez-faire enforcement of antibiotic dispensing regulations in Guatemala combined with patient demand. This study serves as a baseline to document changes in the availability of antibiotics in informal establishments in light of new pharmacy regulations for antibiotic dispensing, which were adopted after this study was completed.
ABSTRACT
Background
The description of local seasonality patterns in respiratory syncytial virus (RSV) incidence is important to guide the timing of administration of RSV immunization products.
...Methods
We characterized RSV seasonality in Guatemala using the moving epidemic method (MEM) with absolute counts of RSV‐associated acute respiratory infections (ARI) from hospital surveillance in Santa Rosa and Quetzaltenango departments of Guatemala.
Results
From Week 17 of 2008 through Week 16 of 2018, 8487 ARI cases tested positive for RSV by rRT‐PCR. Season onsets varied up to 5 months; early seasons starting in late May to early August and finishing in September to November were most common, but late seasons starting in October to November and finishing in March to April were also observed. Both epidemic patterns had similar durations ranging from 4 to 6 months. Epidemic thresholds (the levels of virus activity that signal the onset and end of a seasonal epidemic) calculated prospectively using previous seasons' data captured between 70% and 99% of annual RSV detections. Onset weeks differed by 2–10 weeks, and offset weeks differed by 2–16 weeks between the two surveillance sites.
Conclusions
Variability in the timing of seasonal RSV epidemics in Guatemala demonstrates the difficulty in precisely predicting the timing of seasonal RSV epidemics based on onset weeks from past seasons and suggests that maximal reduction in RSV disease burden would be achieved through year‐round vaccination and immunoprophylaxis administration to at‐risk infants.
•Norovirus and rotavirus were found in 18.5% and 20.4% of stool specimens from children <5 years of age with diarrhea in Guatemala in 2014-2015.•The majority of positive samples were detected in ...children 6–12 months.•Most norovirus infections were caused by GII.4 (63%) and GII.3 (15%) viruses.•Sapovirus genotypes included GI.1, GII.2, GII.5 and GIV viruses.
Acute diarrhea is an important cause of morbidity and mortality in children and is associated with approximately 500,000 deaths/year globally. Rotavirus and norovirus are leading causes of acute diarrhea accounting for more than half of this burden.
To determine the prevalence and genotype distribution of acute diarrhea caused by rotavirus, norovirus, sapovirus and astrovirus among children <5 years of age at two departments in Guatemala from January 2014 to December 2015, we tested 471 stool specimens (202 samples from hospitalized children and 269 samples from children in ambulatory clinics) by real-time reverse transcription-PCR and genotyped positive samples.
Rotavirus was detected in 20.4%, norovirus in 18.5%, sapovirus in 7% and astrovirus in 4.2% of the samples. Co-infection of rotavirus and norovirus was found in 2.6% of the samples. Most norovirus (87.4%) and rotavirus (81.3%) infections were detected in children in the 6–12 months age group. The proportion of patients with rotavirus (34%) and norovirus (23%) was higher in hospitalized patients compared to ambulatory patients, whereas the prevalence of sapovirus and astrovirus was similar in both settings. Of the 40 genotyped norovirus strains, 62.5% were GII.4 and 15% GII.3. Sapovirus genotypes included GI.1 (15.4%), GII.2 (15.4%), GII.5 (38.5%) and GIV.1 (30.8%).
Our data demonstrate that in 2014–2015, gastroenteritis viruses account for 50% of acute diarrhea in children younger than 5 years of age in Guatemala, highlighting the importance of continuous surveillance to guide impact of the current rotavirus vaccine and formulation of future norovirus vaccines.
With their increasing availability in resource-limited settings, mobile phones may provide an important tool for participatory syndromic surveillance, in which users provide symptom data directly ...into a centralized database.
We studied the performance of a mobile phone app-based participatory syndromic surveillance system for collecting syndromic data (acute febrile illness and acute gastroenteritis) to detect dengue virus and norovirus on a cohort of children living in a low-resource and rural area of Guatemala.
Randomized households were provided with a mobile phone and asked to submit weekly reports using a symptom diary app (Vigilant-e). Participants reporting acute febrile illness or acute gastroenteritis answered additional questions using a decision-tree algorithm and were subsequently visited at home by a study nurse who performed a second interview and collected samples for dengue virus if confirmed acute febrile illness and norovirus if acute gastroenteritis. We analyzed risk factors associated with decreased self-reporting of syndromic data using the Vigilant-e app and evaluated strategies to improve self-reporting. We also assessed agreement between self-report and nurse-collected data obtained during home visits.
From April 2015 to June 2016, 469 children in 207 households provided 471 person-years of observation. Mean weekly symptom reporting rate was 78% (range 58%-89%). Households with a poor (<70%) weekly reporting rate using the Vigilant-e app during the first 25 weeks of observation (n=57) had a greater number of children (mean 2.8, SD 1.5 vs mean 2.5, SD 1.3; risk ratio RR 1.2, 95% CI 1.1-1.4), were less likely to have used mobile phones for text messaging at study enrollment (61%, 35/57 vs 76.7%, 115/150; RR 0.6, 95% CI 0.4-0.9), and were less likely to access care at the local public clinic (35%, 20/57 vs 67.3%, 101/150; RR 0.4, 95% CI 0.2-0.6). Parents of female enrolled participants were more likely to have low response rate (57.1%, 84/147 vs 43.8%, 141/322; RR 1.4, 95% CI 1.1-1.9). Several external factors (cellular tower collapse, contentious elections) were associated with periods of decreased reporting. Poor response rate (<70%) was associated with lower case reporting of acute gastroenteritis, norovirus-associated acute gastroenteritis, acute febrile illness, and dengue virus-associated acute febrile illness (P<.001). Parent-reported syndromic data on the Vigilant-e app demonstrated agreement with nurse-collected data for fever (kappa=.57, P<.001), vomiting (kappa=.63, P<.001), and diarrhea (kappa=.61, P<.001), with decreased agreement as the time interval between parental report and nurse home visit increased (<1 day: kappa=.65-.70; ≥2 days: kappa=.08-.29).
In a resource-limited area of rural Guatemala, a mobile phone app-based participatory syndromic surveillance system demonstrated a high reporting rate and good agreement between parental reported data and nurse-reported data during home visits. Several household-level and external factors were associated with decreased syndromic reporting. Poor reporting rate was associated with decreased syndromic and pathogen-specific case ascertainment.