Humidity and Temperature Affect Influenza Virus Transmission

[mixin]

Summary: we have shown that aerosol spread is dependent upon both of these parameters:
cold and dry conditions favor influenza virus transmission.
-------------------------------------------------------
Humidity and Temperature Affect Influenza Virus Transmission:
Studies in the Guinea Pig Model

We have recently shown that the guinea pig is highly
susceptible to infection with human influenza viruses and
transmits these viruses by both aerosol and contact routes.
Thus, the guinea pig represents an ideal small mammal in which
to examine influenza virus transmissibility. To gain insight into
the role of weather conditions in the seasonality of influenza,
we used the guinea pig as a tool to investigate the effects
of relative humidity (RH) and temperature on transmission.
Although the seasonal epidemiology of influenza is well
characterized, the underlying reasons for predominant wintertime
spread in temperate climates are not clear. By performing
twenty replicate transmission experiments under controlled
conditions of RH and temperature, we have shown that aerosol
spread is dependent upon both of these parameters: cold and
dry conditions favor influenza virus transmission. We found
that infected guinea pigs housed at 5?C shed virus at peak
titers for approximately two days longer than animals housed
at 20?C, an observation which likely accounts for the improved
transmission seen at 5?C. The observed relationship between
transmission via aerosols and RH is similar to the reported
relationship between the stability of influenza virus in aerosols
and RH, implying that the effects of humidity act largely at the
level of the survival of virus particles in the environment. Our
data provide direct, experimental evidence to support the
role of climatic conditions in the epidemiology of influenza.
Furthermore, our findings are likely to be applicable to efforts
to control epidemic influenza: the spread of influenza virus
in healthcare and community settings could potentially be
curtailed through internal environmental control.

http://www.isirv.org/media/pdf/OptionsVI_proceedings.pdf

(Big download; thanks to gs for helping)

[tropical]

Re: Humidity and Temperature Affect Influenza Virus Transmission

#1:
"... cold and dry conditions favor influenza virus transmission ..."


Probably the above must have some additional "on the field" additions.

It does obviously, but what happen if this dry and cold conditions are mixed with strong winds?
Supposedly then the air in the spoted area would be fast cleaned from the exhaled virus droplets/particles, because of the strong venting.

Additionaly, the humidity "in favor" issue can't be so easily displaced.
When the fog is heavy and persistent for days, the flu cases seems to spread more than in an windy dry day environment, why if dry is better?

The wind component seems to be important, as it is when is suggested to aerage with outside air the closed rooms of respiratory patients during the convalescence.

[gsgs]

Re: Humidity and Temperature Affect Influenza Virus Transmission

http://www.flutrackers.com/forum/showthread.php?t=38538

[mixin]

Re: Humidity and Temperature Affect Influenza Virus Transmission

I should have done a search for the article before posting.

Thanks linking, that was a good discussion.