Why diphtheria has returned to NSW after more than a century

It’s been dubbed the anti-vax capital of Australia, and now this is the latest weird thing to emerge from northern NSW.In the early 1900s, diphtheria caused more deaths in Australia than any other infectious disease.Since then, the introduction of diphtheria vaccines almost wiped out the disease, but it has resurfaced recently in two children in NSW.A two-year-old child became the first case of diphtheria of the throat in NSW in a century earlier this month.The child has been released from intensive care but remains stable in hospital, a North Coast Public Health Unit (NCPHU) spokeswoman said on Monday.Another child, aged 6, described as a close family contact, was also diagnosed with diphtheria of the throat in northern NSW. That child was admitted to hospital as a precaution and discharged last week.Both children were not vaccinated against the disease. Their close contacts were given post-exposure prophylaxis, which can include antibiotics and immunisation, to reduce the risk of spread.The NCPHU confirmed on Monday that no further cases had since been identified.Diphtheria is a preventable disease and it’s rare these days to see cases in Australia because vaccination rates in Australian children are high, sitting around 95 per cent.But while vaccination prevents the disease, it does not fully prevent people carrying the bacteria in the back of their throat without symptoms, according to Healthdirect Australia chief medical officer Nirvana Luckraj.It was possible for fully vaccinated people to spread the bacteria to unvaccinated contacts, including upon return from overseas travel, she said.“Diphtheria was a concerning issue in Australia in the early 1900s, but thanks to the vaccines being rolled out nationally, it has almost disappeared,” Dr Luckraj said.“Prior to the two recent cases in NSW, there have been no cases of respiratory diphtheria in children in Australia since 1992.”The disease spreads when a person breathes in droplets from an infected person’s cough or sneeze or, rarely, from infected skin lesions.Dr Luckraj said it was unlikely many more diphtheria cases would surface given it was part of the national immunisation program.In Australia, children are vaccinated at six weeks, four months, six months, 18 months, four years and at the beginning of high school.But if they have missed or postponed any of their diphtheria vaccine doses, which are usually administered as part of the diphtheria, tetanus and pertussis (DTP) vaccine, then they could be at risk of infection.In adults, the diphtheria vaccine is included with the tetanus and pertussis vaccines, which are recommended for adults every 10 years and in pregnancy.“Vaccination is the best form of prevention against the disease, so it’s important that people are aware of their vaccination status and up to date with their vaccines,” Dr Luckraj said.“As with many other diseases we are currently dealing with, practising good hygiene can also help to prevent the disease from spreading.”While no other cases of throat diphtheria have been reported in NSW since the 1990s, on rare occasions other less serious cases of diphtheria have been reported, mainly involving the skin.The diphtheria vaccination is free from your GP.Originally published as Why a disease that was prominent more than a century ago has returned to northern NSW