The United States’ Centers for Disease Control and Prevention (CDC) has issued a health alert after the first case of H5N1 avian influenza, or bird flu, seemingly spread from a cow to a human.

A farm worker in Texas contracted the virus amid an outbreak in dairy cattle. This is the second human case in the US; a poultry worker tested positive in Colorado in 2022.

The virus strain identified in the Texan farm worker is not readily transmissible between humans and therefore not a pandemic threat. But it’s a significant development nonetheless.

Some background on bird flu

There are two types of avian influenza: highly pathogenic or low pathogenic, based on the level of disease the strain causes in birds. H5N1 is a highly pathogenic avian influenza.

H5N1 first emerged in 1997 in Hong Kong and then China in 2003, spreading through wild bird migration and poultry trading. It has caused periodic epidemics in poultry farms, with occasional human cases.

Influenza A viruses such as H5N1 are further divided into variants, called clades. The unique variant causing the current epidemic is H5N1 clade 2.3.4.4b, which emerged in late 2020 and is now widespread globally, especially in the Americas.

In the past, outbreaks could be controlled by culling of infected birds, and H5N1 would die down for a while. But this has become increasingly difficult due to escalating outbreaks since 2021.

Wild animals are now in the mix

Waterfowl (ducks, swans and geese) are the main global spreaders of avian flu, as they migrate across the world via specific routes that bypass Australia. The main hub for waterfowl to migrate around the world is Quinghai lake in China.

But there’s been an increasing number of infected non-waterfowl birds, such as true thrushes and raptors, which use different flyways. Worryingly, the infection has spread to Antarctica too, which means Australia is now at risk from different bird species which fly here.

H5N1 has escalated in an unprecedented fashion since 2021, and an increasing number of mammals including sea lions, goats, red foxes, coyotes, even domestic dogs and cats have become infected around the world.

Wild animals like red foxes which live in peri-urban areas are a possible new route of spread to farms, domestic pets and humans.

Dairy cows and goats have now become infected with H5N1 in at least 17 farms across seven US states.

What are the symptoms?

Globally, there have been 14 cases of H5N1 clade 2.3.4.4b virus in humans, and 889 H5N1 human cases overall since 2003.

Previous human cases have presented with a severe respiratory illness, but H5N1 2.3.4.4b is causing illness affecting other organs too, like the brain, eyes and liver.

For example, more recent cases have developed neurological complications including seizures, organ failure and stroke. It’s been estimated that around half of people infected with H5N1 will die.

The case in the Texan farm worker appears to be mild. This person presented with conjunctivitis, which is unusual.

Food safety

Contact with sick poultry is a key risk factor for human infection. Likewise, the farm worker in Texas was likely in close contact with the infected cattle.

The CDC advises pasteurised milk and well cooked eggs are safe. However, handling of infected meat or eggs in the process of cooking, or drinking unpasteurised milk, may pose a risk.

Although there’s no H5N1 in Australian poultry or cattle, hygienic food practices are always a good idea, as raw milk or poorly cooked meat, eggs or poultry can be contaminated with microbes such as salmonella and E Coli.

If it’s not a pandemic, why are we worried?

Scientists have feared avian influenza may cause a pandemic since about 2005. Avian flu viruses don’t easily spread in humans. But if an avian virus mutates to spread in humans, it can cause a pandemic.

One concern is if birds were to infect an animal like a pig, this acts as a genetic mixing vessel. In areas where humans and livestock exist in close proximity, for example farms, markets or even in homes with backyard poultry, the probability of bird and human flu strains mixing and mutating to cause a new pandemic strain is higher.

The cows infected in Texas were tested because farmers noticed they were producing less milk. If beef cattle are similarly affected, it may not be as easily identified, and the economic loss to farmers may be a disincentive to test or report infections.

How can we prevent a pandemic?

For now there is no spread of H5N1 between humans, so there’s no immediate risk of a pandemic.

However, we now have unprecedented and persistent infection with H5N1 clade 2.3.4.4b in farms, wild animals and a wider range of wild birds than ever before, creating more chances for H5N1 to mutate and cause a pandemic.

Unlike the previous epidemiology of avian flu, where hot spots were in Asia, the new hot spots (and likely sites of emergence of a pandemic) are in the Americas, Europe or in Africa.

Pandemics grow exponentially, so early warnings for animal and human outbreaks are crucial. We can monitor infections using surveillance tools such as our EPIWATCH platform.

The earlier epidemics can be detected, the better the chance of stamping them out and rapidly developing vaccines.

Although there is a vaccine for birds, it has been largely avoided until recently because it’s only partially effective and can mask outbreaks. But it’s no longer feasible to control an outbreak by culling infected birds, so some countries like France began vaccinating poultry in 2023.

For humans, seasonal flu vaccines may provide a small amount of cross-protection, but for the best protection, vaccines need to be matched exactly to the pandemic strain, and this takes time. The 2009 flu pandemic started in May in Australia, but the vaccines were available in September, after the pandemic peak.

To reduce the risk of a pandemic, we must identify how H5N1 is spreading to so many mammalian species, what new wild bird pathways pose a risk, and monitor for early signs of outbreaks and illness in animals, birds and humans. Economic compensation for farmers is also crucial to ensure we detect all outbreaks and avoid compromising the food supply.

C Raina MacIntyre, Professor of Global Biosecurity, NHMRC L3 Research Fellow, Head, Biosecurity Program, Kirby Institute, UNSW Sydney; Ashley Quigley, Senior Research Associate, Global Biosecurity, UNSW Sydney; Haley Stone, PhD Candidate, Biosecurity Program, Kirby Institute, UNSW Sydney; Matthew Scotch, Associate Dean of Research and Professor of Biomedical Informatics, College of Health Solutions, Arizona State University, and Rebecca Dawson, Research Associate, The Kirby Institute, UNSW Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

With so many high-profile people diagnosed with cancer we are confronted with the stark reality the disease can strike any of us at any time. There are also reports certain cancers are increasing among younger people in their 30s and 40s.

On the positive side, medical treatments for cancer are advancing very rapidly. Survival rates are improving greatly and some cancers are now being managed more as long-term chronic diseases rather than illnesses that will rapidly claim a patient’s life.

The mainstays of cancer treatment remain surgery, chemotherapy, radiation therapy, immunotherapy, targeted therapy and hormone therapy. But there are other treatments and strategies – “adjunct” or supportive cancer care – that can have a powerful impact on a patient’s quality of life, survival and experience during cancer treatment.

Keep moving if you can

Physical exercise is now recognised as a medicine. It can be tailored to the patient and their health issues to stimulate the body and build an internal environment where cancer is less likely to flourish. It does this in a number of ways.

Exercise provides a strong stimulus to our immune system, increasing the number of cancer-fighting immune cells in our blood circulation and infusing these into the tumour tissue to identify and kill cancer cells.

Our skeletal muscles (those attached to bone for movement) release signalling molecules called myokines. The larger the muscle mass, the more myokines are released – even when a person is at rest. However, during and immediately after bouts of exercise, a further surge of myokines is secreted into the bloodstream. Myokines attach to immune cells, stimulating them to be better “hunter-killers”. Myokines also signal directly to cancer cells slowing their growth and causing cell death.

Exercise can also greatly reduce the side effects of cancer treatment such as fatigue, muscle and bone loss, and fat gain. And it reduces the risk of developing other chronic diseases such as heart disease and type 2 diabetes. Exercise can maintain or improve quality of life and mental health for patients with cancer.

Emerging research evidence indicates exercise might increase the effectiveness of mainstream treatments such as chemotherapy and radiation therapy. Exercise is certainly essential for preparing the patient for any surgery to increase cardio-respiratory fitness, reduce systemic inflammation, and increase muscle mass, strength and physical function, and then rehabilitating them after surgery.

These mechanisms explain why cancer patients who are physically active have much better survival outcomes with the relative risk of death from cancer reduced by as much as 40–50%.

Mental health helps

The second “tool” which has a major role in cancer management is psycho-oncology. It involves the psychological, social, behavioural and emotional aspects of cancer for not only the patient but also their carers and family. The aim is to maintain or improve quality of life and mental health aspects such as emotional distress, anxiety, depression, sexual health, coping strategies, personal identity and relationships.

Supporting quality of life and happiness is important on their own, but these barometers can also impact a patient’s physical health, response to exercise medicine, resilience to disease and to treatments.

If a patient is highly distressed or anxious, their body can enter a flight or fight response. This creates an internal environment that is actually supportive of cancer progression through hormonal and inflammatory mechanisms. So it’s essential their mental health is supported.

Putting the good things in: diet

A third therapy in the supportive cancer care toolbox is diet. A healthy diet can support the body to fight cancer and help it tolerate and recover from medical or surgical treatments.

Inflammation provides a more fertile environment for cancer cells. If a patient is overweight with excessive fat tissue then a diet to reduce fat which is also anti-inflammatory can be very helpful. This generally means avoiding processed foods and eating predominantly fresh food, locally sourced and mostly plant based.

Muscle loss is a side effect of all cancer treatments. Resistance training exercise can help but people may need protein supplements or diet changes to make sure they get enough protein to build muscle. Older age and cancer treatments may reduce both the intake of protein and compromise absorption so supplementation may be indicated.

Depending on the cancer and treatment, some patients may require highly specialised diet therapy. Some cancers such as pancreatic, stomach, esophageal, and lung cancer can cause rapid and uncontrolled drops in body weight. This is called cachexia and needs careful management.

Other cancers and treatments such as hormone therapy can cause rapid weight gain. This also needs careful monitoring and guidance so that, when a patient is clear of cancer, they are not left with higher risks of other health problems such as cardiovascular disease and metabolic syndrome (a cluster of conditions that boost your risk of heart disease, stroke and type 2 diabetes).

Working as a team

These are three of the most powerful tools in the supportive care toolbox for people with cancer. None of them are “cures” for cancer, alone or together. But they can work in tandem with medical treatments to greatly improve outcomes for patients.

If you or someone you care about has cancer, national and state cancer councils and cancer-specific organisations can provide support.

For exercise medicine support it is best to consult with an accredited exercise physiologist, for diet therapy an accredited practising dietitian and mental health support with a registered psychologist. Some of these services are supported through Medicare on referral from a general practitioner.

For free and confidential cancer support call the Cancer Council on 13 11 20.

Rob Newton, Professor of Exercise Medicine, Edith Cowan University

This article is republished from The Conversation under a Creative Commons license. Read the original article.