Tracking down a killer disease

By Martin Johnston

By MARTIN JOHNSTON

For the past 13 years an uncontrolled epidemic has raged in New Zealand, maiming or killing hundreds of New Zealanders, mainly the young.

Meningococcal disease, a mouthful of a scientific term, has become a nightmare for parents of young children - how to avoid it, how to distinguish it from the flu, how to cope with its aftermath.

More than 5400 people have caught the disease, which can cause meningitis and blood poisoning, and 220 have died. A further 1080 have suffered serious disabilities, such as limb amputations or brain damage.

Eight out of 10 victims are under 20 and half are under 5. The disease affects Maori at twice the rate of Pakeha and Pacific Islanders at four times the rate.

Most Western countries have fewer than three cases for every 100,000 people each year. New Zealand has around 15 and in the worst year, 2001, the rate hit 17.4. In the years immediately before the epidemic started in 1991, the rate was 1.5.

Around 4 per cent of New Zealanders who catch the disease die, an internationally low proportion credited to high awareness of the illness' frightening features, such as the lightning speed with which it can develop.

This meningococcal "season", two infants have become the face of the epidemic: Charlotte Cleverley-Bisman, 7 months, and Sakiusa "Junior" Uluvula, 9 months.

Both went from being mildly unwell to critically sick within hours. Both became virtually unrecognisable as blood poisoning turned their bodies purple and black. Both have had multiple limb amputations

Their parents have hailed this week's provisional licensing of a vaccine against the disease, the breakthrough for which the country has been longing. But Junior's mother, Tima Uluvula, wonders why it was not available sooner. She is not alone.

Professor Diana Lennon, an Auckland University paediatric infectious diseases specialist and meningococcal vaccine expert, has expressed her frustration to Herald reporters over delays in developing the vaccine.

In 1999 she publicly chided the Health Ministry. "Decisions need to be made fast. They really don't have that sense of urgency," she said.

"And they don't have the sense that this has got to get going, because otherwise next winter another 600 people will get the disease and another 5 per cent of those - another 30 people - will die next winter."

But now she is more restrained, not wanting to jeopardise the Government's $200 million plan to vaccinate everyone aged from 6 weeks to 19 years against the disease over the next 18 months.

"We had to find a way of getting a manufacturer or public health institute interested in our issue and developing a vaccine for us and not for themselves," she says.

Or as the ministry puts it: "It was not commercially attractive to develop a vaccine specifically for New Zealand."

Efforts began in the mid-90s to develop a vaccine to target the particular group B strain of the disease that was becoming dominant in the New Zealand epidemic, and which would eventually be responsible for more than 80 per cent of cases.

Vaccines existed for other groups and strains - vaccination was offered during an Auckland group A outbreak in the 1980s - but not for the dominant New Zealand strain, although Dutch scientists tested a possible candidate.

Cuba and Norway, like the Netherlands, had suffered B group epidemics and developed vaccines. Norway's incidence of the disease had reached 23.9 cases per 100,000.

It was not until 1992 that New Zealand's dominant strain was identified, at the Institute of Environmental Science and Research (ESR). Principal scientist Dr Diana Martin recalls the excitement in the lab when her team identified the organism responsible for the rising number of cases - but it was tempered by the recognition that "it's not very nice for the community".

In one sense they stumbled on the discovery.

Dr Martin wanted to know more about the bug that had caused around 80 cases of meningococcal disease in 1991, 30 more than usual.

The trigger was a 1992 cluster of cases among Canterbury University students, including one death. In the ensuing panic, the universities' annual Easter Tournament was cancelled for fear of spreading the bacterium - which is thought to reside in the throats of a fifth of people, mostly without harming them.

She could only say that it was caused by a group B strain - not which particular strain - until she imported the special antibodies needed for more detailed testing.

Her team found that the students had been affected by the same strain that had caused an outbreak in Norway, but that strain was different from the one that had caused New Zealand's 1991 increase and which had become its main one.

They delved back to 1988, but the first cases they found of the dominant strain were from 1990. They also found that a genetic match for this strain had been identified in Dutch cases several years earlier.

"We have to surmise that the Netherlands may have been a source of our organism in New Zealand, but we can't confirm it," Martin says.

Wherever it came from once the bug was in New Zealand, it spread quickly.

"The first cases were distributed right throughout the country," Martin says. "It wasn't just happening in Auckland. That's been the case all the way through. We've had cases down the West Coast, in Bluff, Northland."

Lennon credits Martin and her Dutch contacts with starting the search for a New Zealand vaccine, but progress was patchy.

"Someone recommended a new person coming into the picture at the World Health Organisation [in 1998]," Lennon says. "I got in touch with him, got the train from Paris to Geneva - I was in Paris for a meeting - and talked to him.

"He pulled together a meeting, sanctioned by New Zealand, brought together the manufacturers and then it still didn't move.

"Then the discussion between the chair of that meeting and the New Zealand Government put it on to lesser, antibody trials."

The Netherlands produced a small amount of experimental vaccine against the Dutch/New Zealand strain, but commitment was lacking in both countries.

"In the end the vaccine expired, which was tragic really. It was used in one trial by them. At least they were able to show that the vaccine against our strain was able to produce antibodies."

Norway and Cuba also drifted out of the frame. Norway reduced vaccine production as its epidemic waned and Cuba, which has since met European and US manufacturing standards, was at the time not considered up to scratch by New Zealand, although it would eventually sell more than 60 million doses in Latin America.

Lennon says it was only after "a change in personnel" and progress towards commercial links between drug companies and the Cuban, Norwegian and Dutch public health institutes that the New Zealand vaccine project accelerated.

The drug companies "paraded their capabilities" to the ministry in New Zealand in 2000. One was the California-based Chiron Corporation, which had teamed up with the Norwegian institute.

The ministry signed up with Chiron the following year and in 2002, the Government voted $200 million over five years for the evolving vaccine strategy.

But during the years of uncertainty, when a vaccine seemed distant, the despairing Lennon and others looked for alternative ways of alleviating the epidemic. Some turned to the environmental factors that might increase a person's likelihood of becoming infected by the bug - factors that could be weakened.

Martin notes the closeness in timing of the 1991 start of the epidemic and the National Government's introduction of market rents in state housing.

"You can't say that caused it, but the crowding of houses that occurred subsequent to that in South Auckland may have enabled greater spread of the organism."

The spread of infectious diseases is linked with poverty and the associated increase in household overcrowding.

New Zealand research published in 2000 showed that overcrowding intensified the effect of the meningococcal epidemic.

The presence of an extra two adults or adolescents in a six-room, average-sized house increased by 50 per cent the risk of children contracting the disease. The risk was 10 times greater if three families were living in one home.

The Labour-led Government's response was to increase the stock of state houses, introduce income-related rents, and spend tens of millions of dollars on a "healthy housing programme" to improve the design of hundreds of state houses.

But the biggest hope of stopping the epidemic is Chiron's Italian-made vaccine.

Called MeNZB, it is modified from the Norwegian B group vaccine to target the New Zealand strain.

Without it, the ministry expects the epidemic could continue for another decade, killing and maiming nearly as many people as it has in the past 13 years.

On Wednesday, Health Minister Annette King announced the Government's provisional licensing of MeNZB, effectively declaring it safe and effective. This will allow the start of what is believed to be the country's biggest mass-vaccination campaign.

The intention is to offer the vaccine, delivered in three injections, free to all 1.15 million people aged 6 weeks to 19 years within the next 18 months.

The goal is for 90 per cent of them to have the injections, first in Auckland, then progressively from Northland down to Wellington, followed by Southland up to Nelson.

The licence so far permits the vaccine to be used on those aged 6 months to 19 years, because the trials in babies down to 6 weeks old are not yet complete.

But vaccines remain controversial. Some parents refuse to have their children vaccinated for fear of adverse reactions, although vaccine supporters say the risks of these reactions are less than of the diseases themselves.

The Immunisation Awareness Society says the meningococcal disease vaccine plan ignores the risk factors, such as overcrowding. Addressing them might reduce it and other diseases.

Lennon says the vaccine "seems to work in all age groups. It produces antibodies right down to 6 months. We have yet to finish the trials in the 6 to 10 week, the very young kids, alongside their routine vaccine.

"In terms of side effects ... most of the adults had a sore arm and 50 per cent plus had sore arms in the smaller kids and redness and that goes away fairly quickly. Perhaps half the kids had some sort of flu-like symptoms in association."

It is now only nine days to go until the first injections are given - to infants in South and East Auckland, in some of the country's highest-risk suburbs for the disease. And with the nation's attention again focused on the killer disease, the sense of anticipation is high.

MENINGOCOCCAL DISEASE: THE DEADLY SIGNS TO WATCH OUT FOR

Meningococcal disease is a bacterial infection that can cause meningitis and blood poisoning.

Meningitis is inflammation of the membranes covering the brain and spinal cord. Blood poisoning, or septicaemia, occurs with the rapid spread of bacteria and their toxins and can soon lead to organ damage.

The disease is caused by a bacteria called Neisseria meningitidis, known as a meningococcus. The disease is commonly called meningitis. But this is misleading because meningitis is only one of the potential outcomes.

Meningitis can also be caused by other bacteria and there is a viral form.

Amoebic meningitis, a rare but often fatal disease, is caused by an organism that can enter through the nose if you immerse your head in a contaminated hot pool.

Various types of meningococcal bug live in the throats of a fifth of people, mostly without harming them. But it penetrates the defences of a few people.

It can be spread by close contact, including kissing and sharing drink bottles.

Symptoms in children and babies include: fever, refusing drinks or food, being hard to rouse, vomiting, unsettled, a rash or spots, headache, dislike of bright light. In adults they include: fever/headache, vomiting, sleepy, stiff neck, aversion to bright light, muscle pain, rash or spots.

People with symptoms should see a doctor urgently. It can be life-threatening but can be treated with antibiotics.


* For further information about the vaccination programme, see the website Ministry of Health information site or phone 0800 203090

Herald Feature: Meningococcal Disease

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