Maybe you feel worn out. Perhaps you’re also having trouble losing weight. Generally, you just don’t feel 100%.

Could it be Hashimoto’s disease? This common autoimmune thyroid disorder is when your immune system (which fights off viruses and bacteria), mistakenly attacks a part of your body. In this case, it’s your thyroid – a gland located at the base of your neck – and can cause low thyroid hormones levels (hypothyroidism).

Hypothyroidism affects one in 33 Australians and Hashimoto’s is one of the most common thyroid conditions in first-world countries.

While symptoms can be subtle, untreated Hashimoto’s can cause long-term problems with your heart, memory and fertility. Here is what you need to know.

What happens when you have Hashimoto’s?

Your thyroid gland is a butterfly-shaped gland in the neck. It is essential in regulating things like muscle function, digestion, metabolism, the heart and lungs. In children, thyroid hormones are also needed for normal growth and development.

Hashimoto’s thyroid disease, named after the Japanese doctor who discovered it in 1912, is also known as Hashimoto’s thyroiditis or chronic lymphocytic thyroiditis. The disease can cause the immune system to mistakenly produce proteins called antibodies (thyroid peroxidase and thyroglobulin). These can cause inflammation and long-term damage to the thyroid gland. Over time, as thyroid tissue is inflamed and/or destroyed, there can be a decrease in the production of thyroid hormones (hypothyroidism).

Hashimoto’s can present subtly at first. If you only have antibodies with no change in thyroid levels, it is likely you won’t have any symptoms.

However, as the disease progresses, you may experience fatigue, weight gain (or difficulty losing weight), increased sensitivity to the cold, constipation, dry skin, muscle aches, irregular or heavy menstrual cycles, enlarged thyroid (goitre) and occasionally hair loss, including at the ends of your eyebrows.

What causes Hashimoto’s thyroid disease?

Several risk factors can contribute to the development of Hashimoto’s including:

• genetic risk – your risk is higher if you have family members with Hashimoto’s

• gender – women are up to ten times more likely than men to develop the disease

• age – you are more likely to develop the disease from 30 to 50 years of age

• autoimmune condition – having another autoimmune condition like systemic lupus, Type 1 diabetes and celiac disease increases your risk

• excessive iodine intake and radiation exposure may also increase risk in people who are already genetically at greater risk.

What are the long-term risks?

Long-term, untreated Hashimoto’s thyroiditis can cause heart issues, higher cholesterol levels, nerve damage (peripheral neuropathy), reduced cognition and infertility.

In pregnancy, Hashimoto’s has a higher risk of pre-eclampsia (high blood pressure affecting several organs), premature birth, placental abruption (when the placenta separates from the inner wall of the uterus before birth) and, in severe cases, pregnancy loss.

The disease has also been linked with an increased risk (but low incidence) of the lymphocytes of the thyroid turning into cancer cells to cause thyroid lymphoma.

How is Hashimoto’s diagnosed?

Diagnosis can be confirmed with a blood test to check thyroid levels and antibodies.

Thyroid peroxidase antibodies are commonly present but about 5% of patients test antibody-negative. In those people, diagnosis depends on the thyroid levels, clinical presentation and ultrasound appearance of general inflammation. An ultrasound may not be required though, especially if the diagnosis is obvious.

Three hormone levels are tested to determine if you have Hashimoto’s.

Thyroid stimulating hormone (TSH) is produced by the brain to speak to the thyroid, telling it to produce two types of thyroid hormones – T3 and T4.

If you have either relative or absolute thyroid hormone deficiency, a test will show the stimulating hormones as high because the brain is trying to get the thyroid to work harder.

Can it be treated?

The management of Hashimoto’s depends on the severity of the thyroid levels. Up to 20% of the population can have antibodies but normal thyroid levels. This is still Hashimoto’s thyroid disease, but it is very mild and does not require treatment. There is no current treatment to reduce antibody levels alone.

Because thyroid peroxidase antibodies increase the risk of abnormal thyroid levels in the future, regular thyroid testing is recommended.

When the thyroid stimulating hormone is high with normal thyroid hormone levels it is termed “subclinical hypothyroidism”. When it is paired with low hormone levels it is called “overt hypothyroidism”. The first is a mild form of the disease and treatment depends on the degree of stimulating hormone elevation.

Overt hypothyroidism warrants treatment. The main form of this is thyroid hormone replacement therapy (levothyroxine) with the dose of the drug adjusted until thyroid levels are within the normal range. This is usually a lifelong treatment but, once the dose is optimised, hormone levels usually remain relatively stable.

In some people with very enlarged thyroid glands causing compressive symptoms (such as difficulty swallowing or breathing), thyroidectomy (surgical removal of the thyroid) is considered.

Hashimoto’s thyroiditis is a common condition caused by your body’s immune system incorrectly damaging to your thyroid and can go undetected. Long-term, untreated, it can cause issues with your heart, cognition, and fertility. It can be diagnosed with a simple blood test. Speak to your doctor if you have any concerns as early diagnosis and treatment can help prevent complications.

Aakansha Zala, The University of Queensland

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

You might have heard of something called “cryptosporidiosis” recently, closely followed by warnings to stay away from your local swimming pool if you’ve had diarrhoea.

More than 700 cases of this gastrointestinal disease were reported in Queensland in January, which is 13 times more than in January last year. Just under 500 cases have been recorded in New South Wales this year to-date, while other states have similarly reported an increase in the number of cryptosporidiosis infections in recent months.

Cryptosporidiosis has been listed as a national notifiable disease in Australia since 2001.
But what exactly is it, and should we be worried?

What causes cryptosporidiosis, and who is affected?

Cryptosporidiosis is the disease caused by the parasite Cryptosporidium, of which there are two types that can make us sick. Cryptosporidum hominis only affects humans and is the major cause of recent outbreaks in Australia, while Cryptosporidium parvum can also affect animals.

The infection is spread by spores called oocysts in the stools of humans and animals. When ingested, these oocysts migrate and mature in the small bowel. They damage the small bowel lining and can lead to diarrhoea, nausea, vomiting, fever and abdominal discomfort.

Most people develop symptoms anywhere from one to 12 days after becoming infected. Usually these symptoms resolve within two weeks, but the illness may last longer and can be severe in those with a weakened immune system.

Children and the elderly tend to be the most commonly affected. Cryptosporidiosis is more prevalent in young children, particularly those under five, but the disease can affect people of any age.

So how do we catch it?

Most major outbreaks of cryptosporidiosis have been due to people drinking contaminated water. The largest recorded outbreak occurred in Milwaukee in 1993 where 403,000 people were believed to have been infected.

Cryptosporidium oocysts are very small in size and in Milwaukee they passed through the filtration system of one of the water treatment plants undetected, infecting the city’s water supply. As few as ten oocysts can cause infection, making it possible for contaminated drinking water to affect a very large number of people.

Four days after infection a person with cryptosporidiosis can shed up to ten billion oocysts into their stool a day, with the shedding persisting for about two weeks. This is why one infected person in a swimming pool can infect the entire pool in a single visit.

Cryptosporidium oocysts excreted in the faeces of infected humans and animals can also reach natural bodies of water such as beaches, rivers and lakes directly through sewer pipes or indirectly such as in manure transported with surface runoff after heavy rain.

One study which modelled Cryptosporidium concentrations in rivers around the world estimated there are anywhere from 100 to one million oocysts in a litre of river water.

In Australia, cryptosporidiosis outbreaks tend to occur during the late spring and early summer periods when there’s an increase in recreational water activities such as swimming in natural water holes, water catchments and public pools. We don’t know exactly why cases have seen such a surge this summer compared to other years, but we know Cryptosporidium is very infectious.

Oocysts have been found in foods such as fresh vegetables and seafood but these are not common sources of infection in Australia.

What about chlorine?

Contrary to popular belief, chlorine doesn’t kill off all infectious microbes in a swimming pool. Cryptosporidium oocysts are hardy, thick-walled and resistant to chlorine and acid. They are not destroyed by chlorine at the normal concentrations found in swimming pools.

We also know oocysts can be significantly protected from the effects of chlorine in swimming pools by faecal material, so the presence of even small amounts of faecal matter contaminated with Cryptosporidium in a swimming pool would necessitate closure and a thorough decontamination.

Young children and in particular children in nappies are known to increase the potential for disease transmission in recreational water. Proper nappy changing, frequent bathroom breaks and showering before swimming to remove faecal residue are helpful ways to reduce the risk.

Some sensible precautions

Other measures you can take to reduce yours and others’ risk of cryptosporidiosis include:

• avoid swimming in natural waters such as rivers and creeks during and for at least three days after heavy rain
• avoid swimming in beaches for at least one day after heavy rain
• avoid drinking untreated water such as water from rivers or springs. If you need to drink untreated water, boiling it first will kill the Cryptosporidium
• avoid swallowing water when swimming if you can
• if you’ve had diarrhoea, avoid swimming for at least two weeks after it has resolved
• avoid sharing towels or linen for at least two weeks after diarrhoea has resolved
• avoid sharing, touching or preparing food that other people may eat for at least 48 hours after diarrhoea has resolved
• wash your hands with soap and water after going to the bathroom or before preparing food (Cryptosporidium is not killed by alcohol gels and sanitisers).

Not all cases of diarrhoea are due to cryptosporidiosis. There are many other causes of infectious gastroenteritis and because the vast majority of the time recovery is uneventful you don’t need to see a doctor unless very unwell. If you do suspect you may have cryptosporidiosis you can ask your doctor to refer you for a stool test.

Vincent Ho, Associate Professor and clinical academic gastroenterologist, Western Sydney University

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