Superspreader events are pushing up cases of the deadly bacterial infection.
This year’s meningococcal cases have already overtaken last year’s total as more Australians are socialising post-covid.
Cases of invasive meningococcal disease have risen to 86, ahead of last year’s total of 74, according to National Notifiable Diseases Surveillance System data.
Infectious diseases paediatrician Professor Robert Booy, from The Children’s Hospital at Westmead, said cases were rising as people were socialising indoors for longer periods after the end of covid restrictions.
“We’ve just opened up our borders here and we’ve stopped social distancing. We’re having many more social events where people are cheek by jowl, singing, shouting, coughing and kissing.
“We’ve got a lot of superspreader events again, and the superspreader events involve loads of viruses – covid, flu, RSV and other viruses – but could also involve bacteria like the meningococcus.”
The four cases of meningococcal disease associated with last August’s Splendour in the Grass music festival in northern NSW were all different sub-strains of meningococcal B, which indicated there were four separate chains of transmission, Professor Booy said.
“So, the bacterium is out there in the community spreading and it’s more likely to spread in very crowded events.”
Professor Booy said children aged under two and teenagers aged 15 to 19 were particularly at risk. He urged doctors to watch for the different presentations of meningococcal infection.
“Doctors need to be aware of two different syndromes: [septicaemia] and meningitis,” he said.
“The first syndrome is blood poisoning, where the patient gets a fever, fatigue and a rash of purple spots that start as tiny little spots which are petechial, which means that they cannot be pressed away by a glass and the colour remains in the skin because there is bleeding into the skin. Together with that symptom, there can be coldness of the hands and feet.
“Quite separate from that is a meningitis presentation. With meningitis you have a very severe headache, neck stiffness and photophobia … and you may also have the rash and a fever. In babies…the fontanelle may be swollen.”
Most GPs would only see one or two cases of invasive meningococcal disease in their professional career, he said.
“There are only 100 cases a year in Australia, and not all people go to the GP. Some of them get ill so quickly they go straight to hospital.”
Professor Booy said meningococcal B vaccination was recommended in the National Immunisation Handbook, but it was not funded for all children.
“The commonest strain right now is B, and it’s only funded on the National Immunisation Program for indigenous children.”
Professor Booy said it was important for parents of non-indigenous children to discuss the issue with their doctor, and hopefully get a script for the vaccine.
“We have routine vaccination of children against four different serogroups, A, C, Y and W at one year of age and again in the mid-teenage years, but only in South Australia do we have a program of routine vaccination against the meningococcus group B for infants.
“We need a wider application across Australia of routine vaccination against meningococcus group B in infants.”
Professor Booy said patients with invasive meningococcal disease “could go from being a healthy-looking person one day to dead the next”.
Even if meningococcal was diagnosed early and patients survived, they could be left with permanent damage such as scarring, amputation, hearing loss, or problems with memory, attention and concentration, he said.
According to the World Health Organization, about one in 10 people infected with invasive meningococcal disease die and one in five people who survive the infection develop serious long-term complications such as brain damage, deafness or limb loss.
Professor Booy said meningococcal was mediated by damage from respiratory viruses, especially the influenza virus.
“The meningococcus bacterium normally sits quietly as a colonist in the throat as a harmless commensal. But if you’re an unlucky person who’s susceptible when you acquire it, it can invade.
“When you get a flu virus infection, you get a sore throat and that damage to the throat opens up the cells of the throat to being invaded by the previously colonizing meningococcus, and the flu enables it to invade into the bloodstream more easily.”