Australians have suffered a $102bn blow to household income and one-quarter of people believe they will probably lose their jobs in the next year, according to a new study showing the devastating impact of Covid-19 on wellbeing.

In the Australian National University study, released on Thursday, two-thirds of Australians reported feeling anxious or worried about their own and others’ safety and 607,000 have already lost their jobs due to Covid-19 and associated restrictions.

Matthew Gray, one of the report’s co-authors, said the drop in employment from 62.0% of the population in February to 58.9% in April was “unprecedented in modern Australian economic history”, supporting the Reserve Bank’s conclusion that Covid-19 was responsible for the biggest economic contraction since the Great Depression.

The longitudinal ANU study, the first in Australia since the global pandemic, polled a representative sample of 3,155 people in January/February and then again April.

It found that young people aged 18 to 24 and women from non-English speaking backgrounds had suffered the greatest decrease in employment. The proportion of young people in jobs fell from 60.2% to 52.7%.

Gray warned that based on previous downturns, young people would face lifelong impacts and “those who leave the labour force when close to retirement age may never return”.

For those still in work, hours worked fell from an average of 35 to 32 a week. When combined with the drop in jobs, total hours worked fell by 56.2m or 13%.

The report found average household after-tax weekly income fell 9.1% from $1,795 in February to $1,632 in April. Average income per person fell from $740 a week to $663, about 10.4%.

Very low income earners in the lowest decile actually experienced a 33.5% boost in incomes from $160 to $213 a week, most likely due to the $1,500 fortnightly jobkeeper wage subsidy and the doubling of the jobseeker unemployment benefit to $1,100 a fortnight with the coronavirus supplement.

The report noted the “one exception” was 18- to 24-year-olds, who were more likely to be short-term casuals excluded from jobkeeper, who suffered a $64-a-week drop in income compared with an identical person aged 25 or over.

Based on the $102bn drop in household income and estimates that if Australia let coronavirus run its course without a society-wide lockdown it would cause 134,000 deaths, the ANU researchers calculated the “initial economic cost” per life saved has been $761,000.

About 28.4% of respondents said they thought the likelihood they would lose their job in the next 12 months was 50% or higher. The report’s co-author Nicholas Biddle said perceived levels of job insecurity were “very high”: almost twice as high as they had been since 2001.

The study found – consistent with the Guardian Essential poll – that women are more concerned about the health impact of Covid-19 and supportive of restrictions on movement.

Almost four in 10 people said they feel it was either very likely (4.3%) or likely (35.2%) that they would be infected with the coronavirus in the next six months.

A “significant minority” of respondents (19.7%) agreed that “there has been too much unnecessary worry about the Covid-19 outbreak”.

Since January there were big increases in Australians’ confidence in all tiers of government and the public service. Confidence in the federal government recovered from its lows during the summer bushfires, up from 27% in February to 57% in April.

Trust in state and territory governments was up from 40% to 67% and the public service was up from 49% to 65%.

The report argued that while Australia has “done extremely well in limiting the level of infections and deaths” there was “strong initial [evidence] that this has come at the cost of deterioration in mental health and increases in psychological distress”.

Life satisfaction has declined from an average rating of 7.05 out of 10 in October, to 6.9 in January and then to 6.5 in April.

The report estimated the decline from January to April was equivalent to a decline in income of $581 per person per week, or moving from the top 20% of income earners to the bottom third.

The average decrease in life satisfaction for an 18- to 24-year-old (between January and April) was more than three times that of the average decrease for a 65- to 74-year-old, and the life satisfaction of a person 75 years and over actually increased.