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The Lancet. Microbe Aug 2021Adoption of molecular techniques to detect infection has revealed many previously undetected (by microscopy) yet transmissible low-density infections. The proportion of... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Adoption of molecular techniques to detect infection has revealed many previously undetected (by microscopy) yet transmissible low-density infections. The proportion of these infections is typically highest in low transmission settings, but drivers of submicroscopic infection remain unclear. Here, we updated a previous systematic review of asexual prevalence by microscopy PCR in the same population. We aimed to explore potential drivers of submicroscopic infection and to identify the locations where submicroscopic infections are most common.
METHODS
In this systematic review and meta-analysis we searched PubMed and Web of Science from Jan 1, 2010, until Oct 11, 2020, for cross-sectional studies reporting data on asexual prevalence by both microscopy and PCR. Surveys of pregnant women, surveys in which participants had been chosen based on symptoms or treatment, or surveys that did not involve a population from a defined location were excluded. Both the number of individuals tested and the number of individuals who tested positive by microscopy or PCR, or both, for infection were extracted. Bayesian regression modelling was used to explore determinants of the size of the submicroscopic reservoir including geographical location, seasonality, age, methodology, and current or historical patterns of transmission.
FINDINGS
Of 4893 identified studies, we retained 121 after screening and removal of duplicates. 45 studies from a previous systematic review were included giving 166 studies containing 551 cross-sectional survey microscopy and PCR prevalence pairs. Our results show that submicroscopic infections predominate in low-transmission settings across all regions, but also reveal marked geographical variation, with the proportion of infections that are submicroscopic being highest in South American surveys and lowest in west African surveys. Although current transmission levels partly explain these results, we find that historical transmission intensity also represents a crucial determinant of the size of the submicroscopic reservoir, as does the demographic structure of the infected population (with submicroscopic infection more likely to occur in adults than in children) and the PCR or microscopy methodology used. We also observed a small yet significant influence of seasonality, with fewer submicroscopic infections observed in the wet season than the dry season. Integrating these results with estimates of infectivity in relation to parasite density suggests the contribution of submicroscopic infections to transmission across different settings is likely to be highly variable.
INTERPRETATION
Significant variation in the prevalence of submicroscopic infection exists even across settings characterised by similar current levels of transmission. These differences in submicroscopic epidemiology potentially warrant different approaches to targeting this infected subgroup across different settings to eliminate malaria.
FUNDING
Bill & Melinda Gates Foundation, The Royal Society, and the UK Medical Research Council.
Topics: Adult; Bayes Theorem; Child; Cross-Sectional Studies; Female; Humans; Malaria; Malaria, Falciparum; Plasmodium falciparum; Pregnancy
PubMed: 34382027
DOI: 10.1016/S2666-5247(21)00055-0 -
PloS One 2021Florida's waters are a reservoir for a host of pathogens and toxins. Many of these microorganisms cause water-related diseases in people that are reportable to the...
BACKGROUND
Florida's waters are a reservoir for a host of pathogens and toxins. Many of these microorganisms cause water-related diseases in people that are reportable to the Florida Department of Health. Our objective in this review was to ascertain which water-related pathogens and toxins of public health importance have been found in animal populations in Florida over the last twenty years.
METHODS
Nineteen databases were searched, including PubMed and Web of Science Core Collection, using keywords and search terms for the waterborne diseases, water-related vector-borne diseases, and water-based toxins reportable to the Florida Department of Health. For inclusion, peer-reviewed journal articles were to be written in English, published between January 1, 1999 and December 31, 2019, and contain primary research findings documenting at least one of the water-related pathogens or toxins of interest in an animal population within Florida during this same time frame.
RESULTS
Of over eight thousand initial search results, 65 studies were included for final analysis. The most common animal types implicated in the diseases of interest included marine mammals, fish and shellfish, wild birds, and livestock. Toxins or pathogens most often associated with these animals included toxin-producer Karenia brevis, vibriosis, Escherichia coli, and Salmonellosis.
DISCUSSION/CONCLUSION
Findings from this review elucidate the water-related disease-causing pathogens and toxins which have been reported within animal populations in recent Florida history. As most of these diseases are zoonotic, our results suggest a One Health approach is necessary to support and maintain healthy water systems throughout the state of Florida for the protection of both human and animal populations.
Topics: Animal Population Groups; Animals; Data Management; Dinoflagellida; Florida; Public Health; Waterborne Diseases
PubMed: 34324547
DOI: 10.1371/journal.pone.0255025 -
European Journal of Epidemiology Jul 2021Coronavirus disease (COVID-19) is a respiratory disease affecting many people and able to be transmitted through direct and perhaps indirect contact. Direct contact... (Meta-Analysis)
Meta-Analysis
Coronavirus disease (COVID-19) is a respiratory disease affecting many people and able to be transmitted through direct and perhaps indirect contact. Direct contact transmission, mediated by aerosols or droplets, is widely demonstrated, whereas indirect transmission is only supported by collateral evidence such as virus persistence on inanimate surfaces and data from other similar viruses. The present systematic review aims to estimate SARS-CoV-2 prevalence on inanimate surfaces, identifying risk levels according to surface characteristics. Data were obtained from studies in published papers collected from two databases (PubMed and Embase) with the last search on 1 September 2020. Included studies had to be papers in English, had to deal with coronavirus and had to consider inanimate surfaces in real settings. Studies were coded according to our assessment of the risk that the investigated surfaces could be contaminated by SARS-CoV-2. A meta-analysis and a metaregression were carried out to quantify virus RNA prevalence and to identify important factors driving differences among studies. Thirty-nine out of forty retrieved paper reported studies carried out in healthcare settings on the prevalence of virus RNA, five studies carry out also analyses through cell culture and six tested the viability of isolated viruses. Overall prevalences of SARS-CoV-2 RNA on high-, medium- and low-risk surfaces were 0.22 (CI [0.152-0.296]), 0.04 (CI [0.007-0.090]), and 0.00 (CI [0.00-0.019]), respectively. The duration surfaces were exposed to virus sources (patients) was the main factor explaining differences in prevalence.
Topics: COVID-19; Equipment Contamination; Fomites; Humans; Microbial Viability; Prevalence; RNA, Viral; SARS-CoV-2
PubMed: 34313896
DOI: 10.1007/s10654-021-00784-y -
Iranian Journal of Public Health Dec 2020Leishmaniasis is one of the most important parasitic diseases in the Golestan Province, northeastern Iran. In this study, we summarize the results of studies on the... (Review)
Review
BACKGROUND
Leishmaniasis is one of the most important parasitic diseases in the Golestan Province, northeastern Iran. In this study, we summarize the results of studies on the disease and its causative agent Leishmania in humans, vectors and reservoirs in the Golestan Province, Iran.
METHODS
We retrieved all articles related to leishmaniasis in the Golestan Province, northern Iran from 1994 to 2018 in various databases including PubMed, Scopus and Web of Science. Articles in Persian were retrieved from the IranMedex, SID and Magiran. Reference lists of relevant articles were also hand-searched. Local active researchers in the field of leishmaniasis were contacted to avoid missing any relevant articles. Overall, 54 papers were extracted, later evaluated by two research team members based on inclusion criteria. All analyses were performed using the Stata 14 software. Pooled prevalence was calculated using the metaprop command and a random-effect model. The I statistic was used for measuring heterogeneity of studies.
RESULTS
Ten articles in the province were related to detection of Leishmania species in patients with suspected cutaneous or visceral leishmaniasis. Fifteen articles were dedicated to identification of Leishmania species in disease reservoirs and five articles were about detection of the parasite in sand flies. The pooled prevalence of in patients with acute ulcer, wild rodents and sandflies was 83%, 29% and 11%, respectively.
CONCLUSION
Our findings highlight the need for implementation of control measures among the reservoirs of both cutaneous and visceral leishmaniasis in the Golestan Province, Iran.
PubMed: 34178737
DOI: 10.18502/ijph.v49i12.4813 -
F1000Research 2021SARS-CoV-2 RNA has been detected in fomites which suggests the virus could be transmitted via inanimate objects. However, there is uncertainty about the mechanistic...
SARS-CoV-2 RNA has been detected in fomites which suggests the virus could be transmitted via inanimate objects. However, there is uncertainty about the mechanistic pathway for such transmissions. Our objective was to identify, appraise and summarise the evidence from primary studies and systematic reviews assessing the role of fomites in transmission. This review is part of an Open Evidence Review on Transmission Dynamics of SARS-CoV-2. We conduct ongoing searches using WHO Covid-19 Database, LitCovid, medRxiv, and Google Scholar; assess study quality based on five criteria and report important findings on an ongoing basis. We found 64 studies: 63 primary studies and one systematic review (n=35). The settings for primary studies were predominantly in hospitals (69.8%) including general wards, ICU and SARS-CoV-2 isolation wards. There were variations in the study designs including timing of sample collection, hygiene procedures, ventilation settings and cycle threshold. The overall quality of reporting was low to moderate. The frequency of positive SARS-CoV-2 tests across 51 studies (using RT-PCR) ranged from 0.5% to 75%. Cycle threshold values ranged from 20.8 to 44.1. Viral concentrations were reported in 17 studies; however, discrepancies in the methods for estimation prevented comparison. Eleven studies (17.5%) attempted viral culture, but none found a cytopathic effect. Results of the systematic review showed that healthcare settings were most frequently tested (25/35, 71.4%), but laboratories reported the highest frequency of contaminated surfaces (20.5%, 17/83). The majority of studies report identification of SARS-CoV-2 RNA on inanimate surfaces; however, there is a lack of evidence demonstrating the recovery of viable virus. Lack of positive viral cultures suggests that the risk of transmission of SARS-CoV-2 through fomites is low. Heterogeneity in study designs and methodology prevents comparisons of findings across studies. Standardized guidelines for conducting and reporting research on fomite transmission is warranted.
Topics: COVID-19; Fomites; Hospitals; Humans; RNA, Viral; SARS-CoV-2
PubMed: 34136133
DOI: 10.12688/f1000research.51590.3 -
Phytotherapy Research : PTR Aug 2021Traditional Indian medical practices (Ayurveda, Siddha, Unani, and homeopathy) are a vast reservoir of knowledge about medicinal plants. The promising pharmacological...
Traditional Indian medical practices (Ayurveda, Siddha, Unani, and homeopathy) are a vast reservoir of knowledge about medicinal plants. The promising pharmacological properties of these plants have paved the way for developing therapy against novel Coronavirus (CoV) infection. The current review will summarize published works of literature on the effects of traditional Indian medicinal plants against acute respiratory infection (COVID-19, SARS, Influenza, and Respiratory syncytial virus infection) and registered clinical trials of traditional Indian herbal medicines in COVID-19. The current study aims to comprehensively evaluate the data of traditional Indian medicinal plants to warrant their use in COVID-19 management. PubMed, Embase, and Cochrane databases were searched along with different clinical trial databases. A total of 22 relevant traditional Indian medicinal plants (35 relevant studies) were included in the current study having potential antiviral properties against virus-induced respiratory illness along with promising immunomodulatory and thrombolytic properties. Further, 36 randomized and nonrandomized registered clinical trials were also included that were aimed at evaluating the efficacy of herbal plants or their formulations in COVID-19 management. The antiviral, immunomodulatory, and thrombolytic activities of the traditional Indian medicinal plants laid down a strong rationale for their use in developing therapies against SARS-CoV-2 infection. The study identified some important potential traditional Indian medicinal herbs such as Ocimum tenuiflorum, Tinospora cordifolia, Achyranthes bidentata, Cinnamomum cassia, Cydonia oblonga, Embelin ribes, Justicia adhatoda, Momordica charantia, Withania somnifera, Zingiber officinale, Camphor, and Kabusura kudineer, which could be used in therapeutic strategies against SARS-CoV-2 infection.
Topics: Humans; India; Medicine, Ayurvedic; Plant Preparations; Plants, Medicinal; Randomized Controlled Trials as Topic; COVID-19 Drug Treatment
PubMed: 34132429
DOI: 10.1002/ptr.7150 -
BioMed Research International 2021Hospital-acquired infections have remained a serious cause of mortality, morbidity, and extended hospitalization. Bacterial contamination of inanimate surfaces of the... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Hospital-acquired infections have remained a serious cause of mortality, morbidity, and extended hospitalization. Bacterial contamination of inanimate surfaces of the hospital environment and equipment is considered a major contributing factor to the development of several nosocomial infections worldwide. The hospital environment and many devices are an important reservoir of many clinically important bacterial agents including multidrug-resistant pathogens. Therefore, this systematic review and meta-analysis are aimed at investigating bacterial pathogens and their antimicrobial resistance patterns of inanimate surfaces and equipment in Ethiopia.
METHODS
An exhaustive literature search was carried out using the major electronic databases including PubMed, Web of Science, MEDLINE, EMBASE, CINAHL, Google Scholar, Cochrane Library, Scopus, and Wiley online library to identify potentially relevant studies without date restriction. Original articles which address the research question were identified, screened, and included using the PRISMA flow diagram. Data extraction was prepared in Microsoft Excel, and data quality was assessed by using 9-point Joanna Briggs Institute critical appraisal tools. Then, data were exported to STATA 16.0 software for analyses of pooled estimation of outcome measures. Estimation of outcome measures at a 95% confidence interval was performed using DerSimonian-Laird's random-effects model. Finally, results were presented via text, figures, and tables.
RESULTS
A total of 18 studies with 3058 bacterial isolates recovered from 3423 swab specimens were included for systematic review and meta-analysis. The pooled prevalence of bacterial contamination of inanimate surfaces and equipment was found 70% (95% CI: 59, 82). Among the Gram-negative bacterial species, the prevalence of ampicillin-resistant was the highest 80% (95% CI: 78, 92) followed by species 78% (95% CI: 57, 83).
CONCLUSION
This study has shown a high prevalence of bacterial contamination of inanimate surfaces and equipment in Ethiopia.
Topics: Anti-Bacterial Agents; Bacteria; Drug Resistance, Bacterial; Equipment Contamination; Ethiopia; Humans; Iatrogenic Disease; Prevalence
PubMed: 34095296
DOI: 10.1155/2021/5519847 -
Le Infezioni in Medicina Jun 2021In recent years, and now especially with the arrival of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), there has been increased interest in... (Meta-Analysis)
Meta-Analysis
In recent years, and now especially with the arrival of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), there has been increased interest in understanding the role of bats in the dynamics of transmission and origin of this pandemic agent. To date, no systematic reviews have been published on this topic. This systematic review aimed to summarize and highlight the frequency of bat infections reported in currently available observational studies for coronavirus. The purpose of this study was also to examine the differences between the pool prevalence by technique and country. We performed a systematic literature review with meta-analysis, using three databases to assess coronavirus (CoV) infection in bats and its diagnosis by serological and molecular tests. We carried out random-effects model meta-analysis to calculate the pooled prevalence and 95% confidence interval (95% CI). In all, 824 articles were retrieved (1960-2021). After screening by abstract/title, 43 articles were selected for full-text assessment. Of these, 33 were finally included for qualitative and quantitative analyses. From the total of studies, the pool prevalence by RT-PCR (n=14,295 bats) for CoV was 9.8% (95% CI 8.7-10.9%); Italy reported the highest pooled prevalence (44.9%, 95% CI 31.6-58.1%), followed by the Philippines (29.6%). Regarding the ELISA, the pool prevalence for coronavirus from 15 studies, including 359 bats, was 30.2% (95% CI 14.7-45.6%). The results for coronaviruses with the MIF were significantly lower, 2.6% (95% CI 1.5-3.7%). A considerable proportion of infected bats tested positive, particularly by molecular tests. This essential condition highlights the relevance of bats and the need for future studies to detail their role as potential reservoirs of SARS-CoV-2. In this meta-analysis, bats were positive in almost 10% by RT-PCR, suggesting their relevance and the need to understand their potential participation in maintaining wild zoonotic transmission.
Topics: Animals; Bias; COVID-19; Chiroptera; Confidence Intervals; Disease Reservoirs; Observational Studies as Topic; Prevalence; SARS-CoV-2; Seroepidemiologic Studies
PubMed: 34061782
DOI: No ID Found -
PLoS Neglected Tropical Diseases May 2021Elimination of visceral leishmaniasis (VL) in Southeast Asia and global control of cutaneous leishmaniasis (CL) and VL are priorities of the World Health Organization... (Meta-Analysis)
Meta-Analysis
Elimination of visceral leishmaniasis (VL) in Southeast Asia and global control of cutaneous leishmaniasis (CL) and VL are priorities of the World Health Organization (WHO). But is the existing evidence good enough for public health recommendations? This meta-review summarises the available and new evidence for vector control with the aims of establishing what is known about the value of vector control for the control of CL and VL, establishing gaps in knowledge, and particularly focusing on key recommendations for further scientific work. This meta-review follows the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) criteria, including (1) systematic reviews and meta-analyses (SRs/MAs) for (2) vector control methods and strategies and (3) for the control of CL and/or VL. Nine SRs/MAs were included, with different research questions and inclusion/exclusion criteria. The methods analysed for vector control can be broadly classified into (1) indoor residual spraying (IRS); (2) insecticide-treated nets (ITNs; including insecticide-impregnated bednets); (3) insecticide-treated curtains (ITCs; including insecticide-treated house screening); (4) insecticide-treated bedsheets (ITSs) and insecticide-treated fabrics (ITFs; including insecticide-treated clothing) and (5) durable wall lining (treated with insecticides) and other environmental measures to protect the house; (6) control of the reservoir host; and (7) strengthening vector control operations through health education. The existing SRs/MAs include a large variation of different primary studies, even for the same specific research sub-question. Also, the SRs/MAs are outdated, using available information until earlier than 2018 only. Assessing the quality of the SRs/MAs, there is a considerable degree of variation. It is therefore very difficult to summarise the results of the available SRs/MAs, with contradictory results for both vector indices and-if available-human transmission data. Conclusions of this meta-review are that (1) existing SRs/MAs and their results make policy recommendations for evidence-based vector control difficult; (2) further work is needed to establish efficacy and community effectiveness of key vector control methods with specific SRs and MAs (3) including vector and human transmission parameters; and (4) attempting to conclude with recommendations in different transmission scenarios.
Topics: Animals; Asia, Southeastern; Communicable Disease Control; Disease Reservoirs; Humans; Insect Control; Insect Vectors; Insecticide-Treated Bednets; Insecticides; Leishmaniasis, Cutaneous; Leishmaniasis, Visceral
PubMed: 33983930
DOI: 10.1371/journal.pntd.0009309 -
Parasites & Vectors Apr 2021Dirofilariosis is a vector-borne parasitosis caused by filarial nematodes of the genus Dirofilaria. In humans, who represent accidental hosts, dirofilariosis is mostly... (Review)
Review
BACKGROUND
Dirofilariosis is a vector-borne parasitosis caused by filarial nematodes of the genus Dirofilaria. In humans, who represent accidental hosts, dirofilariosis is mostly caused by Dirofilaria repens and Dirofilaria immitis. In Austria, the first reported case occurred in 1978. Since then, several (case) reports have been published.
METHODS
A systematic and retrospective review of collected published cases and new, unpublished confirmed cases of human dirofilariosis occurring in Austria was performed. A nematode was extracted from the eyelid of a previously unreported case and subsequently characterized histologically and using molecular biology techniques.
RESULTS
Data on a total of 39 cases of human dirofilariosis in Austria occurring between 1978 and 2020 are summarized. Over the past four decades the incidence has markedly increased, in particular after 1998. Of the 39 patients, men and women were equally affected, and the mean age was 47.1 years. The area most frequently affected was the head (38.5% of cases). Confined ocular involvement was observed in 23.1% of cases, and nematodes were isolated from the neck/trunk, extremities and the genito-inguinal area in 25.6, 15.4 and 15.4% of patients, respectively. Microfilariae were detected in two cases. Of the 39 patients, only 73.9% tested positive for anti-filarial antibodies and 56.3% for eosinophilia, despite successful isolation of a nematode; consequently, these measures did not represent reliable markers for dirofilariosis. Most patients had a travel history to countries endemic for Dirofilaria species. One patient who had not traveled abroad represented the only autochthonous case recorded to date. Dirofilaria repens was the predominant species, identified in 89.7% of cases. In the newly reported case of subcutaneous dirofilariosis, a live non-gravid Dirofilaria repens adult female of 12 cm length was isolated from the eyelid of the patient, and a video of the extraction is provided.
CONCLUSIONS
The incidence of human dirofilariosis cases has increased strikingly over the last four decades in Austria. More cases can be expected in the foreseeable future due to changes in human behavior and (travel) activities as well as climate changes and the associated alterations in the availability of the natural reservoir, the vectors and the intrinsic characteristics of the parasite.
Topics: Animals; Austria; Communicable Diseases; Dirofilaria immitis; Dirofilaria repens; Dirofilariasis; Disease Reservoirs; Eyelids; Female; Humans; Incidence; Male; Microfilariae; Retrospective Studies; Vector Borne Diseases
PubMed: 33926526
DOI: 10.1186/s13071-021-04696-4