Three-day fever is a contagious viral disease transmitted by two types of herpes viruses. Viruses 6 and 7 of the human herpes viruses cause the three-day fever. The disease manifests itself by a sudden onset of high fever, which (as the name suggests) lasts 3 – 5 days.
The fever is followed -not always- by a rash on the upper part of the patient’s body, which spreads to arms and legs. The viruses are transmitted by droplet infection, which is why the virus is found in saliva and salivary glands and multiplies in immune cells. Once you have gone through the three-day fever, you get lifelong immunity. Consequently, you cannot contract the three-day fever again. However, the virus is still excreted in saliva and other body fluids.
How long is it contagious?
Carriers of the virus are contagious from 3 days before the outbreak of fever until the beginning of the rash. For this reason, transmission is often unconscious, as the carrier is not yet aware of the disease. After infection, the incubation period of the disease is between 5 to 17 days, which means that the disease does not appear until a few days after contact with the virus.
How contagious is it for…
Since almost every child is infected with the virus in the first years of life, which triggers the three-day fever and lives through the disease, the body forms so-called antibodies against the viruses, i.e. defense substances against the virus. From this point on, these antibodies provide lifelong immunity, which means that you cannot fall ill again if you have lived through the three-day fever once. In summary, the three-day fever is not contagious for most adults.
Infection among adults is extremely rare due to the immunity and, if infection does occur, it is very harmless and manifests itself with flu-like symptoms such as a cold and sore throat. However, immunity is lost in patients after bone marrow transplants or immunosuppression. In these patients, the virus can cause severe infections of the lungs or brain or resemble the clinical picture of glandular fever.
Newborns are protected by the maternal antibodies that are transmitted via breast milk. However, the maternal antibodies decrease over time and thus, especially infants aged 6 to 12 months, as well as toddlers, become infected with the disease. Transmission is likely to occur via the saliva of parents or other adults and children.
For children it is very contagious and almost every child gains immunity from a past infection. Three-day fever is as contagious for pregnant women as it is for all other adults. Because of the immunity it is very rare for a pregnant woman to become infected with the three-day fever.
However, not every adult is immune to the virus, so it is possible that a pregnant woman could become infected with the virus. If this is the case, the further procedure should be discussed with the attending gynaecologist, as all viral diseases can pose a potential danger to the baby.
