Medical Matters: One of the great success stories for Irish medicine in the past decade occurred in the field of infectious disease. The introduction of a vaccine (Men C) against the C strain of the meningitis bacterium in October 2000 has resulted in a huge decline in the frightening, and sometimes fatal, diseases: meningococcal meningitis and septicaemia.
According to the 2004 annual report of the Health Protection Surveillance Centre (HPSC), in the late 1990s, the Republic had one of the highest rates of meningococcal disease in Europe, with more than 500 cases per year. After the Men C vaccination programme was added to the infant schedule for vaccinations in 2000 and a catch-up programme initiated for those under 23 years of age, the rate of meningitis C plummeted. Only five meningitis C cases occurred in 2004, a massive 96 per cent reduction in incidence compared with the pre Men C vaccine era.
The meningococcus organism accounts for the vast majority of bacterial meningitis cases here. It is divided into a number of subtypes, including A,B,C, W123 and Y. Subgroups B and C were by far the most common, with sub group B now accounting for 82 per cent of meningococcal disease notifications. Group C disease now makes up only 3 per cent of meningitis notifications, compared to 30 per cent in 1999. Both the death rate and morbidity due to meningitis C have also declined substantially.
The meningococcus bug causes two distinct illnesses: meningitis and septicaemia. The classic signs of meningitis in older children and adults include a high temperature, a violent headache and neck stiffness. A dislike of bright light (photophobia) may also occur, as may drowsiness.
The major sign of septicaemia is the development of a particular skin rash. It begins with a cluster of pin prick stops in the skin which gradually join up to form large purple areas of discoloured tissue. The tumbler test is a method for distinguishing a meningococcal septicaemia rash from other, more benign causes. To carry it out, press a glass tumbler firmly against the rash. If it is due to septicaemia, the rash will not fade and will remain visible through the glass. If this happens, you should seek medical advice immediately.
Other signs of meningococcal septicaemia include fever, cold hands and feet and rapid breathing. And it is possible for both meningitis and septicaemia to occur together, leading to a mixture of signs and symptoms.
Meningococcal disease is most common in winter time. This is because the organism is carried in the nose and skin of about 10 per cent of the population. With the increase in upper respiratory infections at this time of year, the bacteria is more readily transmitted via droplets. In susceptible people, the bug can go on to cause inflammation of the lining of the brain and spinal cord (meningitis) or a widespread infection of the blood (septicaemia).
In spite of the advances made with the Men C vaccine and the greater public awareness of the signs of the disease, concerns have arisen in medical circles that in some cases, there has been a delay in starting treatment. This is because the typical skin rash and neck stiffness tend not to develop until patients have the infection for over 12 hours.
So research published online by The Lancet this month, in which doctors from the University of Oxford identified early clinical features of meningococcal disease in children, is most welcome. Dr Matthew Thompson and his colleagues looked at the medical records and spoke to the parents of 450 children who had the disease. They found that the classic symptoms of the disease - rash, headache, stiff neck and sensitivity to light - occurred late in the pre-hospital phase of the illness and that parents and doctors were over-reliant on these.
Some 72 per cent of the children, however, had early symptoms of infection that developed within the first 12 hours of the illness starting. These were leg pain, cold hands and feet and an abnormal skin colour.
"Recognising these early symptoms of infection could increase the proportion of children identified by primary care physicians and shorten the time to hospital admission," Dr Thompson says.
Cold hands and feet, and abnormal skin colour are features of early infection: they represent changes in the peripheral circulation. The leg pain could be a response to the release of inflammatory chemicals. But these symptoms can occur in the more everyday, self-limiting viral infections seen in general practice.
An accompanying editorial suggests that doctors should be encouraged to re-examine a child with these symptoms within four to six hours if early meningococcal disease cannot be ruled out when the patient is first seen.
While further research is clearly needed, and the classic signs of meningococcal disease must not be downplayed, the evidence from this paper is robust enough to suggest that parents and family doctors pay particular attention to a new triad of warning symptoms for meningitis: leg pain, cold extremities and abnormal skin colour.
For more information on meningitis, contact the Meningitis Research Foundation at 1890 413344 or www.meningitis.org
Dr Muiris Houston is pleased to hear from readers but regrets he cannot answer individual queries.