Glandular Fever (Infectious Mononucleosis)
Definition
Glandular fever is the illness which results from infection with the Epstein-Barr virus (EBV) in older children and young adults. In younger children, infection with the virus usually produces nothing more than a mild feverish illness with no distinctive features.
Incidence
The Epstein-Barr virus is found in all communities. In developing countries virtually everyone has been infected by the age of ten while in the West the first encounter is usually delayed until the teens or young adulthood. The difference in age of infection is crucial to the pattern of illness which results. Before the age of 10 the infection is usually unrecognised whereas glandular fever, one of the most unpleasant common illnesses of teenagers and young adults, is likely to develop when they first acquire the virus.
Cause and prevention
EBV is acquired when saliva containing the virus settles on the lining of the mouth and respiratory tract of someone who has never encountered it before. The virus quickly invades lymphocytes, white blood cells which are plentiful in lymphatic glands which drain secretions from these areas. Whether or not the new host becomes ill, the virus persists in these cells for the rest of that person’s life.
The virus appears in the new host’s saliva for a few weeks after entering the host – whether or not that host became ill. As far as we know, the persistence of the virus after illness has subsided does not matter to the host.
There is no equivalent of shingles, for example, even though EBV and VZV (see chicken pox) are similar viruses. However in some tropical countries where malaria is prevalent, children who acquired EBV sub clinically develop tumours made up of rapidly multiplying EBV-infected lymphocytes. These, Burkitt’s lymphomas, most often grow from the jaw.
There is no practical way of preventing infection with EBV although some suggest that people convalescing from glandular fever should refrain from kissing. But the virus spreads through the air too, so a kissing ban would probably make little difference to the spread of infection.
Signs and Symptoms
Taking the world view, most EBV infections are sub clinical but in the West, adolescents and young adults may develop glandular fever. A sore throat and fever are the most common and usually the most troublesome symptoms. The sore throat may be the result of inflammation of the back of the throat, the pharynx (pharyngitis) but in the most recognizable cases the tonsils at the sides of the entrance to the pharynx are red and swollen with white patches projecting from the surface (an exudative tonsillitis).
This appearance is indistinguishable from the tonsillitis caused by bacteria called Streptococci (strep throat) but enlargement of lymph glands at the back of the throat is in favour of glandular fever (glands are enlarged under the angle of the jaw and the front of the throat with both conditions).
The tonsillitis may be so severe that the sufferer is unable to swallow anything and can become dehydrated. Very rarely, the enlarged tonsils and other lymphatic tissues can obstruct breathing. The spleen – an organ composed largely of lymphocytes – found high in the left upper part of the abdomen under the diaphragm – often enlarges and may be felt by an examining doctor.
The liver is usually affected by a mild hepatitis detectable with blood tests and in a few patients the whites of the eyes develop a tinge of jaundice. All these symptoms settle on their own without treatment – the throat and fever usually within about two weeks – but fatigue is common and occasionally persists for months afterwards.
Source:privatehealth.co.uk
Last Editorial Review:20/1/2010
