Women and their families have had concerns about the effects on their babies of breathing the acrid smoke for weeks on end. Because the situation is so unusual, it has been difficult for health authorities to provide accurate advice to expectant mothers. Understandably, the lack of guidance has made people anxious about the health of unborn and newborn babies.

As emergency services and an army of volunteers are beginning to control the fires that have raged across the country - many isolating pregnant women from medical care - a new threat has emerged. As families travel across the globe for the Lunar New Year the poorly-understood Wuhan Coronavirus has swept across China and into other countries.

At the time of writing a number of cases of Coronavirus infection have been confirmed in Australia. Headlines around the world herald alarm and concern as thousands are infected with the virus and dozens appear to have succumbed. The news that medical personnel treating the victims also have died makes us even more uneasy.

For mums-to-be in Australia, after a summer of fear and concern, this new virus has added to the concern of families across the country. Public health campaigns have driven home the message that infectious diseases such as influenza - the flu - and whooping cough can be very serious in pregnancy. How worried should pregnant women be?

The Wuhan virus is a member of the same family of viruses that causes SARS - but because this strain of virus is newly-identified there is very little medical research to underpin our understanding of it. Like many viruses infection causes a range of symptoms ranging from fever and cough to more severe conditions such as pneumonia.

It now seems clear that the virus can be passed from person to person, but the incubation period - how long it takes from contact with the virus to symptoms appearing - is not clear. It also is not clear when a person becomes infectious: whether an infected person can pass it to others before they themselves show signs of the disease. Health authorities are trying to find out these things as soon as they can.

When women become pregnant there are changes in their immune systems. These changes can reduce a woman's resistance to viral infections, and this means they are at greater risk of serious complications from infections such as the 'flu - hence the campaigns for pregnant women to have 'flu vaccinations. Unfortunately at this time there is no vaccination for the Wuhan Coronavirus.

One of the difficulties for doctors is that, in the early stages, it is very difficult to distinguish a cold from the Coronavirus at the moment. Coronavirus, though, has the capacity to progress rapidly and cause high fever and severe chest infection and pneumonia. It seems that the deaths that have occurred from Wuhan virus infection have been in the elderly and those with other illnesses.

The problem for Australia is that this week marks the end of the summer school holidays, and many families will have travelled home. If they spent time at airports in Asia, the US, or Canada, it is remotely possible that they came in contact with a traveller infected with the Wuhan coronavirus. So children who start school with coughs, sneezes, or fevers will be a major concern to other parents.

What should mums-to-be and their families do then? Keep toddlers and other children well away from other children or adults with respiratory symptoms. Frequent and prolonged handwashing with soap - alcohol-based hand sanitizers are not quite as effective with viruses - and staying away from crowds. If there is any suspicion that someone in the family, or a friend, has a cold or 'flu-like illness and they have been travelling or in contact with travellers they should see a doctor immediately.

There are many uncertainties about the Wuhan coronavirus at the moment but authorities are doing their best to protect Australians. It is likely that most pregnant women will be safe from the virus - based on the information we have at the moment - but the same precautions they should take to avoid the 'flu apply to this new and worrisome virus. If you have any worries at all - see your doctor as soon as possible.