illnesses – and that could be because
certain viruses may have evolved to be
more virulent in men than in women.
Viruses are “programmed” to want to
spread, and to do this, they must multiply
in the host’s body. This is what makes
people ill, but causing illness is not the
virus’s intention: indeed, to incapacitate or
kill their host may be counterproductive –
especially in the case of women, as they
can easily pass viruses on to their children
during pregnancy, birth and breastfeeding.
Professor Vincent Jansen and Dr Francisco
Úbeda, of Royal Holloway, University of
London, thus suggest that certain viruses
have evolved to go easier on women.
Many viruses cause more severe illness in
men: for instance, men with tuberculosis
are 1.5 times more likely to die than
women; and men infected with human
papillomavirus are five times more likely to
develop cancer than women. These
discrepancies are usually put down to
differences in men and women’s immune
systems. But Jansen and Úbeda propose
that it could also be because some viruses
can detect their host’s gender, and alter
their virulence accordingly. Alas, the
scientists don’t think their theory can
explain the severity of “man flu”,
however, as mother-child transmission isn’t
important for cold viruses. “To me, man
flu sounds like an excuse for men not to go
to work,” Jansen told New Scientist.
