15 votes

Is it known how often unvaccinated children are contagious with symptom free diseases?

Unvaccinated members of a population contribute to the susceptibility of the rest of the population to disease, especially vulnerable people who cannot be vaccinated. This fact is true whether or not ...
DoctorWhom's user avatar
  • 5,804
11 votes
Accepted

Why does the flu only happen in winter?

This is a really interesting question, because it really isn't as easy as people being a bit more susceptible in the winter. There's no definitive answer yet. Influenza Seasonality: Underlying Causes ...
YviDe's user avatar
  • 6,982
11 votes
Accepted

Transmission of COVID-19 through domesticated animals

Covid-19 is the result of a zoonotic outbreak from bats to an intermediate ( and unidentified host ) thence to humans. It is thought that bats don't suffer the disease themselves as they carry low ...
Graham Chiu's user avatar
  • 13.3k
9 votes
Accepted

Washing hands after going to the washroom to prevent epidemy

Hands play a major role especially in the transmission of blood-borne, fecal, and respiratory tract viruses. Hand washing after use of bathroom aims at preventing the transmission of pathogens, ...
M. Arrowsmith's user avatar
7 votes
Accepted

Is the washing hands in order to protect yourself from COVID-19 backed up by research?

Here's an article that I found helpful, to understand why washing hands with soap is so helpful, and how it helps (Pall Thordarson is a professor of chemistry at the University of New South Wales, ...
aparente001's user avatar
7 votes

How Long Must a Window Remain Open to Decrease the Risk of COVID?

The premise of the question, that viral particles leaving through an open window is the dominant way risk decreases, is flawed. As bob1 notes in the comments, decrease due to loss through the window ...
Ian Campbell's user avatar
  • 3,244
6 votes

Chance of getting sexual transmitted diseases

Assuming that we are talking about the risk of having intercourse one time under the conditions you described, and assuming you do not know if your male partner had an STD, and provided your partner ...
Mark D Worthen PsyD's user avatar
6 votes
Accepted

How do you get infected with HIV?

What should I take care of while sleeping with another woman to protect her against AIDS? Get tested and go see you doctor. CDC.gov: No HIV test can detect HIV immediately after infection. If you ...
Pobrecita's user avatar
  • 2,975
6 votes

Having sex with someone who's had many sexual partners,

This is a very good and important question, not only for you but for other people as well. As people have said in the comments, YES it can be potentially dangerous to have unprotected sexual ...
Tami's user avatar
  • 466
6 votes
Accepted

Will 70% isopropyl alcohol deactivate i.e. kill COVID-19?

Yes, it does. According to the CDC, this is how surfaces should be disinfected: Surfaces Wear disposable gloves when cleaning and disinfecting surfaces. Gloves should be discarded after ...
Carey Gregory's user avatar
  • 9,813
6 votes
Accepted

Why does R_t start so high for COVID in these models?

People don't just act in response to official orders. People react to the perception of danger, and by the time various official responses were announced, they were already taking measures to prevent ...
Mark's user avatar
  • 2,027
6 votes
Accepted

Which is the average infection rate of STDs via oral sex?

Probably the best evidence around this is for HIV, which is neatly summarised in table 2 of the BASHH (British Association for Sexual Health and HIV) guidelines, where the risk for insertive or ...
Michael's user avatar
  • 689
5 votes
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Eradicating HIV

It's quite easy to be infected with HIV and not know it. HIV is notoriously stealthy, often producing no symptoms for months or even years, and in the meantime the person can transmit the disease. ...
Carey Gregory's user avatar
  • 9,813
5 votes
Accepted

Can you get a yeast infection in your mouth from oral sex?

The yeast (fungus) that causes thrush or yeast infection in both men and women are of the genus Candida. These fungi can be found as normal flora on skin however outgrowth results in yeast infection. ...
Kenneth P. Hough's user avatar
5 votes

Can ingesting a mosquito make you sick?

Positively, no. HIV is not spread by mosquitoes. You cannot contract any disease from swallowing a mosquito. Here, is a very large list of all the things that you could have caught :) If you ...
user19679's user avatar
  • 630
5 votes

How can someone that is HIV positive not be contagious?

Your back-of-the-envelope calculations seem to be off in estimating the extent of viral load reduction in a treated versus untreated person as well as the risk of transmission for unprotected, ...
Bryan Krause's user avatar
  • 13.9k
5 votes

Is the washing hands in order to protect yourself from COVID-19 backed up by research?

Yes, the virus can be made un-harmful by soap and water. From the Economist: The outer proteins sit athwart a membrane provided by the cell in which the virion was created. This membrane, made of ...
Mariah's user avatar
  • 171
5 votes

Why has the African region not seen many Covid-19 cases so far?

Health care in many sub-Saharan African countries is extremely sparse. As an example, Sierra Leone has less than 250 doctors for the entire country. As a result, it is likely that cases in that and ...
DrMcCleod's user avatar
  • 532
5 votes

What information we have about transmission of COVID-19 in detail?

This question may a bit too broad (e.g. there are some separate questions about Covid-19 and food) but on the topic of transmission in an office-like setting there have been some studies/reports, some ...
Dolphin 613 Motorboat's user avatar
4 votes
Accepted

Is E. coli contagious?

Yes, E. coli is definitely contagious through direct contact. In fact your girlfriend's pyelonephritis could have come from you after sexual intercourse. The general mechanism for this would be that ...
Atl LED's user avatar
  • 1,933
4 votes
Accepted

Can I save road accident victims with my bare hands?

In short, the answer (regarding diseases) is yes. Anytime you deal with blood or other bodily fluid, you risk catching a variety of diseases. The risk is compounded if you are not wearing proper ...
L.B.'s user avatar
  • 874
4 votes

Is rabies virus infectious outside host?

Can rabies virus remain infectious on environment i.e on soil, grasses, leaves and water? Generally, an exposure requires a bite from an infected animal, or saliva or neural tissue to be introduced ...
De Novo's user avatar
  • 3,188
4 votes
Accepted

Does the evidence show that handshakes during an office visit are safe?

There are arguments made that handshakes in healthcare settings are not safe; for example see Sklansky et al 2014. Some of the issues increasing the risk include noncompliance with hand-washing ...
Bryan Krause's user avatar
  • 13.9k
4 votes
Accepted

Why getting off the transport where person has coughed is not going to help?

There are three possibilities when someone is coughing on the bus: they don't have Coronavirus -- or even a virus at all. I coughed a lot when my lungs were full of tumours. Some people cough when ...
Kate Gregory's user avatar
  • 3,929
4 votes

Is the washing hands in order to protect yourself from COVID-19 backed up by research?

There are obvious sufficient data and enough evidence that all virus are transmitted by droplet infection (body contact) and shake hands. Washing hand makes sense as the infection is happening ...
Albrecht Hügli's user avatar
4 votes

Confusing COVID article - Why would keeping the doubling time above the incubation period flatten the curve?

One of the issues with COVID-19 is the fact that it is transmissible even by people who are asymptomatic. You've probably heard about R0, which is the basic reproduction rate of a disease, that takes ...
Nuclear Hoagie's user avatar
4 votes

Is there a virus from which humans can recover, but which doesn't grant long lasting immunity?

Seasonal coronaviruses come back year after year and we continue to suffer with them Researchers do know that reinfection is an issue with the four seasonal coronaviruses that cause about 10 to 30% ...
Graham Chiu's user avatar
  • 13.3k
4 votes

Why won't COVID-19 just start spreading again once quarantine is re-opened?

The virus has actually continued to spread during the lockdowns, just at a slower pace than if no lockdown had been imposed. See for example Washington state in the USA. The hope is that the ...
Charles E. Grant's user avatar
4 votes

After exposure to covid when is someone contagious?

No, and we can state this authoritatively, because to become infectious, the person has be able to put out virus, which means at least a single replicative cycle of the virus before any would be ...
bob1's user avatar
  • 3,456
3 votes
Accepted

Chagas disease: transmission

Mother-to-Child transmission is known as "vertical transmission". Vector transmission exclusively refers to an intermediate organism (often, but not always, an insect).
Fomite's user avatar
  • 2,433

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