Viruses also have their “jump start time” in a day.
“Morning” is the time of the day when people are fully-recharged and most energetic. Same goes to viruses.
A study by University of Cambridge suggests that viruses are more dangerous when they infect their victims in the morning.
The findings showed that viruses were ten times more successful if the infection started in the morning.
If you have a disrupted body clock, caused by shift-work or jet lag, you must keep track of your health because you are always vulnerable to infection.
In the study, mice were infected with either influenza, which causes flu, or herpes virus, which can cause a range of diseases including cold sores.
The mice infected in the morning had 10 times the viral levels of those infected in the evening. The late viruses were failing after essentially trying to hijack a factory after all the workers had gone home.
Further tests showed that disrupting the animal’s body clock meant they were “locked in” to a state that allowed the viruses to thrive.
The researchers used only two viruses in the study.
However, the pair were very distinct (one was a DNA virus the other an RNA virus), which leads the research team to suspect the morning risk may be a broad principle that applies across a wide number of viruses.
About 10% of genes, the instructions for running the human body, change activity throughout the day, and this is controlled by the internal clock.
The research focused on one clock gene called Bmal1, which has its peak activity in the afternoon in both mice and people.
The body clock has been implicated in our susceptibility to infections before, flu jabs appear more effective in morning and jet lag affects the malaria parasite.
The researchers say the findings could lead to new ways of stopping pandemics.
Prof Akhilesh Reddy, one of the researchers, told the BBC News website: “It’s a big difference.
“The virus needs all the apparatus available at the right time, otherwise it might not ever get off the ground, but a tiny infection in the morning might perpetuate faster and take over the body.”
He believes the findings could help control outbreaks of disease.
Prof Reddy said, “In a pandemic, staying in during the daytime could be quite important and save people’s lives, it could have a big impact if trials bear it out”.