A new scientific study has revealed shocking evidence that Covid-19 infection in fathers before conception may negatively impact the brain development and emotional health of their future children. The findings, published in the prestigious journal Nature Communications, suggest that SARS-CoV-2—the virus that causes Covid-19—can alter sperm at a molecular level, leading to increased anxiety-related behaviours in offspring. Scientists say this could have far-reaching implications for future generations.

The study was conducted by researchers at the Florey Institute of Neuroscience and Mental Health, University of Melbourne, Australia. Led by Professor Anthony Hannan, the team explored whether a Covid infection could cause epigenetic changes—biological changes that don’t alter DNA but affect gene function—similar to what has been observed in other environmental exposures like poor diet or stress.

“The father’s experiences can alter the information carried in sperm, including specific RNA molecules, which transmit instructions for offspring development,” explained Prof. Hannan. “We wanted to understand whether Covid-19 could act as one such factor.”

How the study was conducted

In the experiment, male mice were infected with SARS-CoV-2 and allowed to recover. Once recovered, they were mated with healthy female mice. Despite the infection being cleared before breeding, their offspring showed noticeable changes:

• All pups from Covid-infected fathers displayed higher levels of anxiety-like behaviour.

• These behavioural changes appeared even though the fathers were healthy during conception.

• Female offspring showed altered gene activity in the hippocampus, a brain region crucial for memory, emotion regulation, anxiety, and depression.

Dr. Carolina Gubert, a co-author of the study, said the results point to epigenetic inheritance—when traits or conditions are passed on not through DNA mutations but through changes in gene expression caused by external factors. “These changes in the hippocampus may explain the increased anxiety we saw in the offspring,” she said.

Covid altered sperm RNA

Further analysis showed that Covid-19 had changed several RNA molecules in the sperm of infected fathers, including molecules responsible for regulating brain development genes. These changes may interfere with normal neurological growth in offspring.

Could this affect humans?

While the study was conducted on mice, Prof. Hannan warned the potential impact on humans cannot be ignored. “If our findings translate to humans, this could impact millions of children worldwide, and their families, with major implications for public health,” he said. The researchers have now called for urgent human studies to further investigate long-term generational effects of Covid-19.

The study raises important questions about male reproductive health post-Covid and suggests that recovered fathers-to-be may need medical guidance before planning a pregnancy.