While you’re likely familiar with type 1 and type 2 diabetes, you’ve probably heard less about type 1.5 diabetes.

Also known as latent autoimmune diabetes in adults (LADA), type 1.5 diabetes has features of both type 1 and type 2 diabetes.

More people became aware of this condition after Lance Bass, best known for his role in the iconic American pop band NSYNC, recently revealed he has it.

So, what is type 1.5 diabetes? And how is it diagnosed and treated?

There are several types of diabetes

Diabetes mellitus is a group of conditions that arise when the levels of glucose (sugar) in our blood are higher than normal. There are actually more than ten types of diabetes, but the most common are type 1 and type 2.

Type 1 diabetes is an autoimmune condition where the body’s immune system attacks and destroys the cells in the pancreas that make the hormone insulin. This leads to very little or no insulin production.

Insulin is important for moving glucose from the blood into our cells to be used for energy, which is why people with type 1 diabetes need insulin medication daily. Type 1 diabetes usually appears in children or young adults.

Type 2 diabetes is not an autoimmune condition. Rather, it happens when the body’s cells become resistant to insulin over time, and the pancreas is no longer able to make enough insulin to overcome this resistance. Unlike type 1 diabetes, people with type 2 diabetes still produce some insulin.

Type 2 is more common in adults but is increasingly seen in children and young people. Management can include behavioural changes such as nutrition and physical activity, as well as oral medications and insulin therapy.

How does type 1.5 diabetes differ from types 1 and 2?

Like type 1 diabetes, type 1.5 occurs when the immune system attacks the pancreas cells that make insulin. But people with type 1.5 often don’t need insulin immediately because their condition develops more slowly. Most people with type 1.5 diabetes will need to use insulin within five years of diagnosis, while those with type 1 typically require it from diagnosis.

Type 1.5 diabetes is usually diagnosed in people over 30, likely due to the slow progressing nature of the condition. This is older than the typical age for type 1 diabetes but younger than the usual diagnosis age for type 2.

Type 1.5 diabetes shares genetic and autoimmune risk factors with type 1 diabetes such as specific gene variants. However, evidence has also shown it may be influenced by lifestyle factors such as obesity and physical inactivity which are more commonly associated with type 2 diabetes.

What are the symptoms, and how is it treated?

The symptoms of type 1.5 diabetes are highly variable between people. Some have no symptoms at all. But generally, people may experience the following symptoms:

• increased thirst
• frequent urination
• fatigue
• blurred vision
• unintentional weight loss.

Typically, type 1.5 diabetes is initially treated with oral medications to keep blood glucose levels in normal range. Depending on their glucose control and the medication they are using, people with type 1.5 diabetes may need to monitor their blood glucose levels regularly throughout the day.

When average blood glucose levels increase beyond normal range even with oral medications, treatment may progress to insulin. However, there are no universally accepted management or treatment strategies for type 1.5 diabetes.

Type 1.5 diabetes is often misdiagnosed

Lance Bass said he was initially diagnosed with type 2 diabetes, but later learned he actually has type 1.5 diabetes. This is not entirely uncommon. Estimates suggest type 1.5 diabetes is misdiagnosed as type 2 diabetes 5–10% of the time.

There are a few possible reasons for this.

First, accurately diagnosing type 1.5 diabetes, and distinguishing it from other types of diabetes, requires special antibody tests (a type of blood test) to detect autoimmune markers. Not all health-care professionals necessarily order these tests routinely, either due to cost concerns or because they may not consider them.

Second, type 1.5 diabetes is commonly found in adults, so doctors might wrongly assume a person has developed type 2 diabetes, which is more common in this age group (whereas type 1 diabetes usually affects children and young adults).

Third, people with type 1.5 diabetes often initially make enough insulin in the body to manage their blood glucose levels without needing to start insulin medication. This can make their condition appear like type 2 diabetes, where people also produce some insulin.

Finally, because type 1.5 diabetes has symptoms that are similar to type 2 diabetes, it may initially be treated as type 2.

We’re still learning about type 1.5

Compared with type 1 and type 2 diabetes, there has been much less research on how common type 1.5 diabetes is, especially in non-European populations. In 2023, it was estimated type 1.5 diabetes represented 8.9% of all diabetes cases, which is similar to type 1. However, we need more research to get accurate numbers.

Overall, there has been a limited awareness of type 1.5 diabetes and unclear diagnostic criteria which have slowed down our understanding of this condition.

A misdiagnosis can be stressful and confusing. For people with type 1.5 diabetes, being misdiagnosed with type 2 diabetes might mean they don’t get the insulin they need in a timely manner. This can lead to worsening health and a greater likelihood of complications down the road.

Getting the right diagnosis helps people receive the most appropriate treatment, save money, and reduce diabetes distress. If you’re experiencing symptoms you think may indicate diabetes, or feel unsure about a diagnosis you’ve already received, monitor your symptoms and chat with your doctor.

Emily Burch, Accredited Practising Dietitian and Lecturer, Southern Cross University and Lauren Ball, Professor of Community Health and Wellbeing, The University of Queensland

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

Each year, more and more Victorians become sick with a flesh-eating bacteria known as Buruli ulcer. Last year, 363 people presented with the infection, the highest number since 2004.

But it has been unclear exactly how it spreads, until now. New research shows mosquitoes are infected from biting possums that carry the bacteria. Mozzies spread it to humans through their bite.

What is Buruli ulcer?

Buruli ulcer, also known as Bairnsdale ulcer, is a skin infection caused by the bacterium Mycobacterium ulcerans.

It starts off like a small mosquito bite and over many months, slowly develops into an ulcer, with extensive destruction of the underlying tissue.

While often painless initially, the infection can become very serious. If left untreated, the ulcer can continue to enlarge. This is where it gets its “flesh-eating” name.

Thankfully, it’s treatable. A six to eight week course of specific antibiotics is an effective treatment, sometimes supported with surgery to remove the infected tissue.

Where can you catch it?

The World Health Organization considers Buruli ulcer a neglected tropical skin disease. Cases have been reported across 33 countries, primarily in west and central Africa.

However, since the early 2000s, Buruli ulcer has also been increasingly recorded in coastal Victoria, including suburbs around Melbourne and Geelong.

Scientists have long known Australian native possums were partly responsible for its spread, and suspected mosquitoes also played a role in the increase in cases. New research confirms this.

Our efforts to ‘beat Buruli’

Confirming the role of insects in outbreaks of an infectious disease is achieved by building up corroborating, independent evidence.

In this new research, published in Nature Microbiology, the team (including co-authors Tim Stinear, Stacey Lynch and Peter Mee) conducted extensive surveys across a 350 km² area of Victoria.

We collected mosquitoes and analysed the specimens to determine whether they were carrying the pathogen, and links to infected possums and people. It was like contact tracing for mosquitoes.

Molecular testing of the mosquito specimens showed that of the two most abundant mosquito species, only Aedes notoscriptus (a widespread species commonly known as the Australian backyard mosquito) was positive for Mycobacterium ulcerans.

We then used genomic tests to show the bacteria found on these mosquitoes matched the bacteria in possum poo and humans with Buruli ulcer.

We further analysed mosquito specimens that contained blood to show Aedes notoscriptus was feeding on both possums and humans.

To then link everything together, geospatial analysis revealed the areas where human Buruli ulcer cases occur overlap with areas where both mosquitoes and possums that harbour Mycobacterium ulcerans are active.

Stop its spread by stopping mozzies breeding

The mosquito in this study primarily responsible for the bacteria’s spread is Aedes notoscriptus, a mosquito that lays its eggs around water in containers in backyard habitats.

Controlling “backyard” mosquitoes is a critical part of reducing the risk of many global mosquito-borne disease, especially dengue and now Buruli ulcer.

You can reduce places where water collects after rainfall, such as potted plant saucers, blocked gutters and drains, unscreened rainwater tanks, and a wide range of plastic buckets and other containers. These should all be either emptied at least weekly or, better yet, thrown away or placed under cover.

There is a role for insecticides too. While residual insecticides applied to surfaces around the house and garden will reduce mosquito populations, they can also impact other, beneficial, insects. Judicious use of such sprays is recommended. But there are ecological safe insecticides that can be applied to water-filled containers (such as ornamental ponds, fountains, stormwater pits and so on).

Recent research also indicates new mosquito-control approaches that use mosquitoes themselves to spread insecticides may soon be available.

How to protect yourself from bites

The first line of defence will remain personal protection measures against mosquito bites.

Covering up with loose fitted long sleeved shirts, long pants, and covered shoes will provide physical protection from mosquitoes.

Applying topical insect repellent to all exposed areas of skin has been proven to provide safe and effective protection from mosquito bites. Repellents should include diethytolumide (DEET), picaridin or oil of lemon eucalyptus.

While the rise in Buruli ulcer is a significant health concern, so too are many other mosquito-borne diseases. The steps to avoid mosquito bites and exposure to Mycobacteriam ulcerans will also protect against viruses such as Ross River, Barmah Forest, Japanese encephalitis, and Murray Valley encephalitis.

Cameron Webb, Clinical Associate Professor and Principal Hospital Scientist, University of Sydney; Peter Mee, Adjunct Associate Lecturer, School of Applied Systems Biology, La Trobe University; Stacey Lynch, Team Leader- Mammalian infection disease research, CSIRO, and Tim Stinear, Professor of Microbiology, The University of Melbourne

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