Shining light on Q fever

By Jeanette Severs

A MACKINNON Project veterinarian researching Q fever believes there may be a geographic link between herd and human infection.

Dr Tabita Tan’s three-year research project investigated the dairy regions of the Goulburn Valley and Gippsland in Victoria.

It is critical information, given the last research published in Victoria into the prevalence of Q fever in livestock was in 1972.

“We didn’t know if anything had changed and we didn’t really understand the risk to humans from infected livestock,” Dr Tan said.

She sampled 1500 blood tests from across Victoria, to identify data trends. Her research identified there can be a high rate of infection in herds, without obvious signs of the symptoms in livestock. A high intensity of infection in herds also increases the risk of infection for humans.

“You need to get a blood test to properly diagnose Q fever in livestock, because it imitates other diseases,” Dr Tan said.

“It’s a very infectious disease and humans are at highest risk during calving.”

She encourages doctors to automatically include Q fever in the list of possible infections when patients present with symptoms such as unexplained fever.

One dairy farmer still recovering from infection of the organism, Coxiella burnetii, is Casey Bermingham, from Nambrok. She was diagnosed with Q fever in early October 2017.

Before the diagnosis, she was suffering severe fever and migraines, was dehydrated and needed painkillers every four hours.

A nurse as well as a dairy farmer, Mrs Bermingham took herself to hospital and asked for Q fever testing, but initial blood analysis showed negative for antibodies.

“Every time my temperature spiked above 40, at least four times a day, they took blood tests,” Mrs Bermingham said.

It was four weeks before the antibodies showed up in her blood tests. Fortunately, two days after presenting to hospital, she was placed on intravenous fluids and managed as if she had the infection.

Jason and Casey Bermingham were not unaware of Q fever. She is a nurse and he had the vaccination soon after he left school and began dairy farming. What they have found is the infection material can spread over a one kilometre radius from its source.

“The worst thing is the fatigue, which brings on migraines,” Mrs Bermingham said of her ongoing symptoms.

The Berminghams milk a 300-cow split-calving Friesian herd and produce all their own fodder off their 220 ha farm. Before the Q fever infection, Mrs Bermingham milked in the morning, was involved in calf rearing and looked after their two children.

The illness meant she was out of action for six weeks during a hectic time on the farm — irrigating, calving tail-enders, joining heifers and cows and harvesting silage.

Fortunately their parents, also dairy farmers, have been able to help; they also now employ two women full-time to milk. They support their employees to be vaccinated.

“Casey being ill put pressure on the system,” Mr Bermingham said.

“We’ve encouraged our staff to get the vaccination and we’ll pay for it, because it costs us more if they get sick.”

Dr Tan said the annual cost of Q fever to the industry was at least $1 million in lost productivity, medical expenses and potential litigation.

“Recent human outbreaks of Q fever has raised concerns the disease is emerging and increasing,” she said.

Preventing the long lasting disease is the main aim of Q fever vaccination.

According to information on the Australian Q Fever Register, the disease can be spread to humans mainly from dairy and beef cattle, sheep and goats. The germ that causes infection can be spread in the urine, faeces and milk, with birth fluids, placenta and the foetus being the most dangerous sources.

When infected fluids dry out, the highly infectious germ can remain alive in the dust or on hair, hides and fleeces for years — people can be infected by splashed infected fluids or by breathing infected dust.

High pressure washing can spread the infection as an aerosol onto clothing, into a cut on skin and onto buildings.

Inhalation is the most common source of human infection, but it also occurs through cuts in the skin and the eye.

During the slaughter and processing of infected animals, fine mists can be released into the air from the blood and when handling the udder, bladder, intestines, uterus, foetus and other products of conception.

Moving animals with livestock trucks, in stockyards and along laneways can also raise infective dust, effectively putting anyone at risk in rural areas.

People’s symptoms can range from feeling ‘off colour’ to severe fever and sweating, cough, nausea, severe headache, muscle pains, weakness, vomiting and diarrhoea. Onset of the illness may range from 14 to 60 days.

Ongoing problems include extreme tiredness and weakness, muscle pains, headaches, fever and depression.

Cardiac and other organ and central nervous system problems can show up months and years after the initial infection.