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Yes, this helps as well with other infectious diseases. A good example is the flu, which season was measurably shorter this year than in other years on record. See the figure from the reference 1 for comparision: Reference 2 shows that this is also true for other respiratory diseases (figure 2): This shows very well that the isolation measures and the ...


40

In addition to Chris' answer above, the effect is even more pronounced in Southern Hemisphere countries where flu season started during the pandemic. The New Zealand lockdown and health response dramatically lowered the prevalence of reported flu-like symptoms. Reference: Flu Tracking reports - New Zealand – week ending 31-May-2020


6

The following review has extensive answers to the complex of this question. They also include MERS and SARS-Cov-1 in their discussion, as there is good data on them. Huang et al., A systematic review of antibody mediated immunity to coronaviruses: antibody kinetics, correlates of protection, and association of antibody responses with severity of disease ...


6

I think that you could argue that some prion diseases do form epidemics or outbreaks. In some cases it does appear that people have referred to BSE/vCJD as pandemics. There is even some journalism on the topic, and see also here. Infection by prion from the environment does occur at some rate, and it is true that it is these prions are the more transmissible....


5

There are a few viruses which are around for a long time and have caused recurring episodes of disease. Most of these where not pandemic, which is probably more of a problem for modern times due to fast travel/exchange of people and are also a problem of "modern" cities where many people come together in a limited space. Among theses viruses are: ...


4

Data are usually binned in broad age groups partly because that's all the detail that's useful in some context, and because access to more detailed data often involves access to strongly controlled, personally identifiable information. This preprint (full disclosure: I'm a co-author) gives information in 2-year bins for COVID in Ontario, e.g. this graph of ...


4

The studies referenced do not have any such specifics about transmission probability. What they observe is that a variant is becoming more common. Modeling the spread gives a different R0 value for the variants vs the reference strains: In line with previous modelling studies, the R0 for VOC-202012/01 was estimated as 75% more transmissible than other ...


4

The 1890 "Russian Flu" pandemic is now believed to have been caused by one of the common cold Coronaviruses, HCoV-OC43. At the time of historical pandemics, there was no way to identify the infectious agent, though. So connecting the pandemic to the virus is based on descriptions of symptoms, and patterns of which demographic groups were most ...


3

Transmission through inanimate objects is referred to as "fomite" transmission. It's really hard to know exactly how important fomites are for a particular illness. There is, however, strong evidence that respiratory viruses can spread via this method. Generally, the emphasis is on how contact with hands can lead to infection when someone touches ...


3

I have not found texts relevant to your question and related to the spread of SARS-CoV-2. However, here is a publication that discusses the utility of contact duration data when constructing infection models, in the general case -- Simulation of an SEIR infectious disease model on the dynamic contact network of conference attendees Methods At a conference, ...


2

There are populations that might be more vulnerable due to genetics surrounding the ACE2 receptor. For instance, men are more likely than women to get severe cases of COVID-19: A growing body of evidence reveals that male sex is a risk factor for a more severe disease, including death. Indeed, globally, ~60% of deaths from COVID-19 are reported in men7,8, ...


2

To the best of my knowledge, we don't yet know the infectious dose of the SAR-COV-2 virus in humans. In theory, it only takes one viulent virus particle to start an infection. In practice, it's pretty hard to measure, Published estimates of infectious dose for any pathogen don't often account for differences in age or sex, per se, so it's hard to address ...


2

In addition to the first answer that was posted, I would point out that, like many other coronaviruses, SARS-COV-2 is also an enteric pathogen, capable of primary infection in various GI tissues. To my knowledge, there's no conclusive evidence that an orally transmitted GI infection can cause severe respiratory symptoms (or even occur in the absence of ...


1

Generally based on (1). To quote the website: The variants that are cause for most concern may: spread more quickly, evade natural or vaccine-related immunity, cause more severe disease, evade detection by available tests, or are less responsive to treatment. If you look at the features they say they look for in variants, the one they mention first is &...


1

Per Wikipedia, typically when one needs a lot of virus, it is grown in a controlled cell environment. This used to be eggs, but is moving toward cell cultures instead. So basically yes, factories full of virus (though more like in nice discrete bioreactors than big Joker-friendly vats). Synthetic vaccines, such as the mRNA vaccines for COVID, do not need ...


1

The terminology really depends on the scientific field. You also have to be aware that sometimes terminology is simplified for the purposes of presenting information to the general public. A droplet can really mean anything from a few micrometers up to several millimeters and it does not necessarily have to be spherical. The key point is that the virus may ...


1

It's funny: $R_0$ doesn't actually follow as nicely as $1/R_0$ when focusing on the infected class. In a SIS model: $$\frac{\mathrm{d}S}{\mathrm{d}t} = -\beta SI + \alpha I \\ \frac{\mathrm{d}I}{\mathrm{d}t} = \beta SI - \alpha I$$ take finding the steady state of $I$. Whether a disease is able to invade is dependent on whether or not the steady state is ...


1

1/R0 is the threshold fraction. If fraction of population vulnerable to particular infection is more than 1/R0, only then infection can spread further. And if it is less than 1/R0 then infection can not progress and eventually goes away And, 1-1/R0 is the fraction of population which requires vaccination so that we can have herd immunity. (Reference http:/...


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