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)
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)
