10

There is a new law about come into effect in Finland that would, amongst other things, mandate all healthcare employees have yearly vaccinations. Here is a link to the webpage of the new law (in Finnish).

There is also a citizens' initiative (Finnish web-page) aiming to stop the new law from being enforced.

The initiative argues against the effectiveness of these mandatory vaccinations:

Esimerkiksi influenssarokotteen vaikuttavuudesta on saatavilla luotettavaa ja puolueetonta tietoa. Cochrane-katsauksen mukaan henkilökunnan influenssarokotteen suojavaikutuksesta laboratoriotestauksin varmistettuun influenssaan, keuhkokuumeeseen tai kuolleisuuteen 60-vuotiailla ja vanhemmilla hoidettavilla ei ollut näyttöä (3). Kattavaa laumaimmuniteettia on myös erittäin vaikea saavuttaa henkilökunnan rokotuksilla, eikä siitä todennäköisesti ole edes hyötyä potilaille (4). Viime vuosina on ollut myös epäilyjä siitä, että influenssarokotteen teho laskee rokotusten myötä vuosi vuodelta (5). Influenssan torjunnassa tärkeintä on edelleen hyvän hygienian merkitys (4).

And my translation into English:

There is credible and unbiased information regarding the effectiveness of influenza vaccinations. According to Cochrane review there is no evidence between influenza vaccination of (healthcare) personnel to laboratory-tested influenza, pneumonia or mortality of 60 years old and older patients (3). Comprehensive herd-immunity is also very hard to achieve with (healthcare) personnel vaccinations and it won't probably even provide any benefit to patients (4). There has been suspicions in recent years that the efficiency of influenza vaccinations is decreasing year by year (5). The most important aspect on defending from influenza is still good hygiene (4).

The new law would require personnel vaccinations for measles, chicken pox, influenza and pertussis (pertussis only for personnel treating under one year olds). The initiative proposes that part as a whole to be removed.

The corresponding sources to back up these claims are:

(3) Thomas, Jefferson & Lasserson 2016. Influenza vaccination for healthcare workers who care for people aged 60 or older living in long-term care institutions. Cochrane

(4) Dolan ym. 2012. Vaccination of health care workers to protect patients at increased risk for acute respiratory disease. Emerg Infect Dis. 2012 Aug;18(8):1225-34.

(5) Friedman 2015. The flu vaccine may have a strange problem that US scientists can't fix.

Are influenza vaccinations to healthcare personnel effective? Is there a scientific consensus about the matter?

I believe the new law aims to protect the patients better by vaccinating the employees (correct me if I'm wrong). Thus the effectiveness should be scrutinized on the ability to better the patients' safety. The citizens' initiative argues that this goes against the individual autonomy of the workers i.e. educated professionals should have the last say on their own vaccinations.

  • I think you translated a word wrong, and I edited it to what I think is the right word, but it would be helpful to double check. In English, "efficient" means it doesn't use much resources in achieving its goal. A treatment's "efficacy" refers to whether works in ideal conditions (like you might find in a lab test). A treatment's "effectiveness" refers to whether it works in real world conditions. I assume the Finnish word translates to "effective", but it would be good to check. – Oddthinking Dec 21 '17 at 15:40
  • 1
    Just out of interest: What vaccination does the law require and what vaccinations is the initiative against? Is influenza vaccine the only controversial one? – Oddthinking Dec 21 '17 at 15:46
  • I'm not sure what to make of this. You can read the abstracts of the science papers cited yourself ncbi.nlm.nih.gov/pubmed/27251461, ncbi.nlm.nih.gov/pubmed/22840895 They are written in a clear enough language. The 3rd "(5) Friedman" is an opinion piece in Business Insider. Are you asking if there's a scientific consensus of sorts on this matter? Also "effective" for whom? The workers themselves or those they care for? – Fizz Dec 22 '17 at 0:16
  • 4
    As I understand related discussions here in Germany, the first point of vaccinating health care personnel is: in case of an outbreak, you particularly want to make sure the hospitals stay in working condition (vaccinate-the-healthcare-staff is a strategy employed when not aiming at herd immunity). So the first benefit to the patients is that their doctor is working instead of staying home with the flu. Not catching the disease at the doctor's/hospital is far more difficult to achieve (e.g. sharing the waiting room with patients). Thus, IMHO the claims are strawman arguments. – anonymized Dec 22 '17 at 17:05
  • 2
    While I can't address the big picture, I do see a problem here--the flu vaccine only gives immunity to certain strains and even then it's not 100%. Thus there is no expectation that it will protect patients from all cases of the flu due to herd immunity. The intent is to cut down on the number of cases of flu contracted from medical people. – Loren Pechtel Dec 23 '17 at 2:18
7

My answer is going to be wishy washy, so if it reads that way... it's not because I'm misexpressing myself.

As user "anonymized" pointed out, it's not too clear what the premise of the proposed law is: to lessen the chance that healthcare personnel misses work because of flu, or that they protect their patients by not spreading the flu to them. Or maybe both. So, with the risk of making the answer a bit long, let's try to address both.

On the first issue, whether flu vaccines protect the direct recipient, the CDC is firmly on the side of flu vaccination, even though the flu vaccines apparently has a substantial variability in effectiveness, ranged between 10% and 60% in a 2017 news piece in Science. The argument for seems to be that that's [far] better than nothing. The arguments against are more complicated involving potential long-term effects of the vaccine on the flu itself and/or receiver's immunity, which seem harder to weigh. These arguments are raised by reputable scientists in reputable venues, so it's not a case of crackpottery like the opposition to some other vaccines. E.g., one study cited by Friedman's opinion piece says:

In vaccinated subjects with no evidence of prior season vaccination, significant protection (62% [95% CI, 17%–82%]) against community-acquired influenza was demonstrated. Substantially lower effectiveness was noted among subjects who were vaccinated in both the current and prior season. There was no evidence that vaccination prevented household transmission once influenza was introduced; adults were at particular risk despite vaccination.

Some of the authors of this study work for the CDC Influenza Division, by the way.


On the issue of healthcare workers' vaccination protecting their patients from flu, the two reviews mentioned in the question (and their findings):

Our review findings have not identified conclusive evidence of benefit of HCW vaccination programmes on specific outcomes of laboratory-proven influenza, its complications (lower respiratory tract infection, hospitalisation or death due to lower respiratory tract illness), or all cause mortality in people over the age of 60 who live in care institutions.

  • Dolan (2012) reviewed 20 papers of which 4 were RCTS, 10 observational studies and the rest reviews (thereof) to conclude that:

Consistency in the direction of effect was observed across several different outcome measures, suggesting a likely protective effect for patients in residential care settings. However, evidence was insufficient for us to confidently extrapolate this to other at-risk patient groups.

The CDC however has a page which is in favor:

The findings of a recent CDC review of related published literature indicate that influenza vaccination of health care personnel can enhance patient safety. [1,2]

where the two references are a review (Ahmed et al. 2014 based on 4 RCTs and 4 observational studies) and a commentary on it. I'll just quote from the review's abstract:

Influenza vaccination of healthcare personnel (HCP) is recommended in >40 countries. [...] the quality of the evidence for the effect of HCP vaccination on mortality and influenza cases in patients was moderate and low, respectively. The evidence quality for the effect of HCP vaccination on patient hospitalization was low. The overall evidence quality was moderate. CONCLUSIONS: The quality of evidence is higher for mortality than for other outcomes. HCP influenza vaccination can enhance patient safety.

And independently of those I found one review (Kliner (2016)) which reviewed... 11 reviews:

The evidence for employer and patient safety benefits of influenza vaccination is not straightforward and has been interpreted differently by different systematic review authors.

So, yeah, the number of reviews seems to exceed the number of actual RCTs on this (and even the number of observational studies). And they are all flogging the same evidence with a slightly different spin on the conclusion.

  • 2
    The question about whether vaccinating HCW protects patients seems like a pretty difficult research question. Suppose vaccination completely eliminates spread via HCWs. There is still a huge confounding factor of patient to patient transmission, particularly in nursing homes where some of these studies were conducted. Because the signal to noise ratio is expected to be bad, you would need a well designed study and a little bit of luck. +1 for finding the best available evidence. – BobTheAverage Dec 23 '17 at 19:41

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .