@puuppa kyseli maskeista pari päivää sitten;
Results: 58 out of 84 studies met the inclusion criteria, of which 13 were classified as systematic reviews and 45 were quantitative studies (comprising randomised controlled trials, retrospective cohort studies, case control, cross-sectional, surveys, observational and descriptive studies). N = 27 studies were conducted amongst healthcare workers wearing face masks, n = 19 studies among the general population, n = 9 studies among healthcare workers the general population and patients wearing masks, and n = 3 among only patients. F
ace masks use have shown a great potential for preventing respiratory virus transmission including COVID-19.
Regardless of the type, setting, or who wears the face mask, it serves primarily a dual preventive purpose; protecting oneself from getting viral infection and protecting others. Therefore, if everyone wears a face mask in public, it offers a double barrier against COVID-19 transmission.
pubmed.ncbi.nlm.nih.gov
Jännä että jopa danmask jonka tulos oli''ei merkittävää hyötyä'' tuli loppujen lopuks tulokseen noin 50%sti ehkäsee tautia?! Mitä vittua!? Infektioita 50% vähemmän, loppu tulos, ''ei merkittävää hyötyä''?
Conclusion:
The recommendation to wear surgical masks to supplement other public health measures
did not reduce the SARS-CoV-2 infection rate among wearers by more than 50%
1600 sairaalan tutkimus. 66% väheni pärskeet maskin läpi, silti ei tilastollista eroa? Asia kunnossa.
The study looked at the reduction of secondary transmission of SARS-CoV-2 in Beijing households by face mask use (10). It found that face masks were 79% effective in preventing transmission,
The science around the use of masks by the public to impede COVID-19 transmission is advancing rapidly. In this narrative review, we develop an analytical framework to examine mask usage, synthesizing the relevant literature to inform multiple areas: population impact, transmission...
www.pnas.org
However, the review included only three studies of mask use outside health care settings, all of which were of SARS, not of SARS-CoV-2, one of which was incorrectly categorized (it occurred in a hospital, but during family and friend visits), and one of which found that none of the households wearing masks had any infections, but was too underpowered to draw any conclusions (12).
The remaining study found the use of masks was strongly protective, with a risk reduction of 70% for those that always wore a mask when going out (13), but it did not look at the impact of masks on transmission from the wearer. It is not known to what degree analysis of other coronaviruses can be applied to SARS-CoV-2. None of the studies looked at the relative risks of different types of mask.
The study looked at Australian households, was not done during a pandemic, and was done without any enforcement of compliance. It found that “in an adjusted analysis of compliant subjects,
masks as a group had protective efficacy in excess of 80% against clinical influenza-like illness.” However, the authors noted that they “found compliance to be low, but compliance is affected by perception of risk. In a pandemic, we would expect compliance to improve.”
In compliant users, masks were highly effective at reducing transmission.
Mun arvostama cochrane julkasun tulos;
What are the results of the review?
Medical or surgical masks
Seven studies took place in the community, and two studies in healthcare workers. Compared with wearing no mask, wearing a mask may make little to no difference in how many people caught a flu‐like illness (9 studies; 3507 people); and probably makes no difference in how many people have flu confirmed by a laboratory test (6 studies; 3005 people). Unwanted effects were rarely reported, but included discomfort.
Mutta loppu kaneetissa luki, että ei noudatettu ohjeita ja conclusion oli, ''ei hyötyä'' AHA. Jäämpä miettimään kuinka tohon tulokseen tultiin...
Relatively low numbers of people followed the guidance about wearing masks or about hand hygiene, which may have affected the results of the studies.
Silti voidaan vetää johto päätös. The results might change when further evidence becomes available. Relatively low numbers of people followed the guidance about wearing masks or about hand hygiene, which may have affected the results of the studies.
ELi jos vaatimuksena on 100% hyöty, niin miks poliisit käyttää luotiliivejä, miks käsiä pestään; miks autossa on turvavyöt, miks kortsuja käytetään, miks kypärää käytetään pyöräilessä?