Study Shows 1 in 5 Australians Experiencing Long COVID After Positive Test

A study by The Australian National University (ANU) has found around one in five Australians who tested positive for COVID-19 had symptoms consistent with long COVID. Alamy/PA

Around one in five Australians who tested positive for COVID-19 displayed symptoms consistent with long COVID, according to a study by the Australian National University (ANU).

This comes after Queensland’s Chief Health Officer John Gerrard called for the term “long COVID” to be scrapped following a study that found the long-term effects of the virus were no different from the seasonal flu, and that long-term COVID symptoms were not “unique and exceptional” to other viral infections.

Long COVID is described by the World Health Organisation as the continuation or development of new symptoms three months after the initial SARS-CoV-2 infection, with these symptoms lasting for at least two months without any alternative explanation.

The ANU study drew on nearly 71,000 participants in Western Australia (WA) who tested positive for COVID-19 from July 16, 2022, to Aug. 3, 2022.

Of the 70,876 adult participants who consented to the research, 11,697 (16.5 percent) provided complete responses provided by the researchers.

Among the respondents, 2,130 respondents (18.2 percent) satisfied the researchers’ criteria for long COVID—reporting new or ongoing symptoms or health problems 90 days after a positive SARS-CoV-2 test result.

The study found the following:

• Long COVID risk was greater for women, people aged 50–69 years or with pre-existing health conditions, and those with two or fewer COVID-19 vaccine doses.
• Common long COVID symptoms included fatigue and concentration difficulties.
• In a highly vaccinated population not broadly exposed to earlier SARS-CoV-2 variants, 18 percent of people infected with the Omicron variant reported symptoms consistent with long COVID 90 days after infection.
• 18 percent of these people had not fully resumed previous work or study by 3 months, and 38 percent required care from general practitioners for their symptoms 2 to 3 months after infection.

Higher Risk of Developing Long COVID from Omicron Variant

Lead researcher Mulu Woldegiorgis said the results show the risk of developing long COVID from the Omicron variant is higher than originally thought.

“It is more than double the prevalence reported in a review of Australian data from earlier in the pandemic, and higher than similar studies done in the UK and Canada,” Ms. Woldegiorgis said.

“Our finding is, however, lower than that of a recent Queensland study, which found that 21 percent of people reported ongoing symptoms twelve weeks after PCR-confirmed infections with the SARS-CoV-2 Omicron variant,” the researchers wrote.

“Despite reports that the risk of long COVID may be lower following Omicron infections than with earlier SARS-CoV-2 variants, we found that the burden of long COVID may be substantial 90 days after Omicron infections.”

Ms. Woldegiorgis added: “The risk of long COVID was greater for women and people aged 50 to 69, as well as those with pre-existing health conditions and people who’d had fewer vaccine doses.”

Additionally, the study found that 90 percent of the study participants with long COVID reported experiencing multiple symptoms, such as tiredness and fatigue (70 percent), followed by difficulty thinking or concentrating (“brain fog”), sleep problems, and coughing.

A third of women with long COVID also reported changes in their menstrual cycle.

“More than a third of individuals with persistent long COVID—38 percent—had sought medical care in the month prior to the survey,” she said.

“This most frequently involved a visit to a GP, hospitalisations or trips to the emergency department were thankfully less common.”

The study also found that 64 percent of participants with long COVID were able to fully return to work or study within a month of their infection, but 18 percent reported still not being well enough to do so three months after their infection.

The authors noted a number of limitations to the study, including the unclear diagnosis of long COVID, not comparing participants to non-positive participants, and not including asymptomatic or undetected infections.

Link Between Vaccination and Long COVID

While the above study did not look at the link between vaccination and the development of long COVID, a study by Germany’s Martin Luther University Halle-Wittenberg has shown that unvaccinated people infected with the Omicron variant had the lowest risk of long COVID.

The study found that while previous infections reduce the risk of long COVID by 86 percent, vaccination status prior to COVID infection is irrelevant to a person’s risk of developing long COVID.

“Vaccination offered no meaningful protection against developing PCC [post-COVID condition] in case of an infection. In contrast, there was … strong evidence that a previous infection reduced the risk of PCC,” the authors wrote.

However, the authors of the German study acknowledged that none of the participants were given an actual diagnosis of long COVID or tested for comorbidities.

At the same time, a long COVID clinic in England reported a 79 percent drop in referrals that followed the rollout of the second dose of COVID-19 vaccinations, despite having four times as many cases of COVID-19 over the same period.

Meanwhile, a study published by the Lancet found higher rates of lung, brain, and kidney injuries among those with long COVID in the UK, compared with those who did not contract COVID-19.

Marina Zhang and Jack Phillips contributed to this report.