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Deadly meningitis

Hong Kong relatively safe from scourge common in UK

By Kenneth Chow

After a day of work, you go back home with a headache and a light fever. Your brain pressure begins to rise, making your neck stiff and unable to turn except with great pain. Then you fall into a state of semi-consciousness and eventually into a coma.

Under this dangerous state, you cannot make spontaneous movements, execute orders or follow verbal commands.

If not treated, your life will be in danger.

The above are all symptoms of meningitis, a deadly meninges inflammation due to infection.

Dr. Lo Wing Lok, vice-president of the Hong Kong Medical Association, said that there are many kinds of meningitis.

“Meningococcal meningitis is the most common type of meningitis,” he said. “The mortality rate of meningococcal meningitis can be up to 15 percent in foreign countries, thus causing dramatic threats worldwide.”

According to the Meningitis Research Foundation, there were over 2,500 reported cases of meningococcal meningitis and septicaemia in 1997 in the UK. The figure means that four people in every 100,000 of the population were affected.

Meningococcal meningitis is in fact a virus consisting of bacteria, fungus and parasites, said Dr. Lo.

Dr. Lo said that the bacteria of meningitis are spread through “human-to-human” contacts, and about 10 percent of the population in foreign countries are carrying the bacteria.

“The bacteria are parasitic and are living in the noses and throats of human beings.”

Generally speaking, most people can resist such bacteria from developing into meningitis. Their immune systems are enough to combat the pathogens.

Dr. So Man Kit, Department of Medicine of Princess Margaret Hospital, said that there are certain groups of people predisposed to the disease.

“Those whose immunities are weak like babies and young children can easily be infected by the disease.

“Weak functioning of the spleen can make people at risk of infection,” said he.

Dr. So also said that those with immune deficiency due to other diseases or those under treatment are easily subject to infection.

Surprisingly, there has been a massive increase in meningitis among 18- to 25-year-olds in the UK in recent years.

Last autumn, two students in Cambridge were found to have contracted the disease.

“Close human contact like kissing, coughing and sneezing can transfer the bacteria from one person to another through secretions,” Dr. So said.

However, studies noted that the bacteria can only stay alive for a short period in the air owing to temperature difference between the human body and the outside world.

“After infection, the disease can be present in human bodies in three forms,” said Dr. So.

“The first form is only as bacteriaemia, meaning that bacteria are stayed in the blood only. Then, the bacteria will grow in number. Subsequently, it will become septicameia,” said he.

Under the above condition, the bacteria will secrete various substances, including mediators which affect blood supply and damage blood circulation.

“Many organs of the patients will be damaged, causing multi-organ failure.

“The disease can also manifest itself as bacterial meningitis. Then, most of the bacteria are staying in the meninges.

“Brain pressure will increase, causing brain damage and deteriorating mental function,” said Dr. So.

He said that patients feel confusion and suffer from headaches and stiff necks. Eventually, patients fall into a coma.

“The third form is the combination of the two situations mentioned above,” Dr. So continued.

“The bacteria will be at the blood and meninges at the same time, damaging blood circulation and mental functions,” said Dr. So.

Dr. Lo said that the disease can develop in human bodies from several days to two weeks without any symptoms.

“During the outbreak of the disease, it can be indicated by symptoms like fever, headache and shock.

“In more serious cases, patients will suffer from severe headache and high fever followed by coma. There will be small bruises over their skin because of bleeding beneath their skin,” said he.

Dr. Lo said that those patients will eventually die due to severe damage of the brain and spinal cord.

“In certain cases, patients are dead owing to the great damage of adrenal glands controlling the circulation of blood pressure and recovering from stress,” said he.

Dr. Lo said that outbreaks of the disease often happen in crowded areas like school halls and military camps.

“Meningitis can be treated by using appropriate antibiotics or large doses of penicillin,” said he.

Dr. So said that there are three methods to test whether a person is infected.

The first one is blood culture. Blood samples are collected from patients to see whether the number of bacteria grows in number, said he.

“The second method is to collect cerebrospinal fluid by lumbar puncture,” said Dr. So.

“A needle will be put into the space in the meninges to draw out cerebrospinal fluid here. The fluid of an infected patients will be turbid and under high pressure,” said Dr. So.

He said that the third method is the slide test.

Blood samples will be drawn from the patients to test for the presence of specific bacteria and substances of meningitis.

After treatment, patients may suffer from after-effects produced like residual brain damage, impaired vision and deafness, said Dr. So.

In Hong Kong, the number of meningitis cases are far less than that in Western countries.

“It is hard to tell the reason for the situation of Hong Kong,” said Dr. So.

“It may be due to the fact that the climate of Hong Kong is not favorable to the growth of the bacteria.

“Also, ethnic groups may be a factor affecting the situation. Chinese may be less susceptible to the disease than Westerners,” said he.

Also, there is no statistics showing that there will be an outbreak of meningitis among the 18- to 25-year-olds in Hong Kong.

According to the Health Department, for the last 3 years, less than 10 cases each year were reported.

Several years ago, a 60-year-old man with diabetes mellitus was infected by meningitis.

Dr. So said, “At the early period, he suffered from light flu and headache. On the third day, he felt drowsy and sleepy.”

He said that upon arriving hospital, the patient was mentally dull.

After a 14-day treatment, the patient returned to his condition before disease and no after-effect was found.

“The clinical course was smooth during the treatment period,” said Dr. So.

If there is no damage in the nervous system during infection, the chance of after-effects is very low.

The second case involved a 35-year-old backpacker who came down with the infection after traveling on the Silk Road for 6 weeks.

“It is believed that the disease was acquired abroad in this case,” said Dr. So.

“The patient did not receive any pre-travel medical counseling or appropriate vaccinations before the trip.”

He said that the patient was living in hostels and received medical treatment for a light fever during the trip.

“After being back in Hong Kong for several days, the patient got chills, vomited and suffered from severe headaches.

“Fearing that the disease might spread to family members through household contacts, antibiotics for drug prophylaxis were given to play it safe,” he said.

After treatment, the disease was under control and the patient recovered with no side effects.

Though the morbidity and mortality for meningitis is high, Dr. So is quick to tell that the medical facilities owned by hospitals are capable of tackling the situation.

“Laboratories facilities are advanced and sufficient for testing of the bacteria, making the confirmation of diagnoses more accurately and quickly,” said he.

Caused by bacteria, meningitis is inflammation of the brain lining. The bacteria live behind the nose and throat. People with weak immune systems are most at risk. (Courtesy of So Man Kit)

Internet Links:
Hong Kong Medical Association
Department of Health

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