You may have seen a social media video: "Five signs of your autism." You may have heard of the long-term waiting list for autism diagnosis. You may know or feel that the number of people considered autistic is rising rapidly.

There are many dangers. These numbers mean something drastic to different people. Autism is a fear for some (what if this happens to my kids?); for others, it is an identity, even a superpower.

So what is the truth about the number of autistic patients? What does this mean?

To calculate something, you first need to say what you want to calculate.

In order for someone to be diagnosed with autism, they need to “persistent difficulties in social life and social communication,” said Ginny Russell, associate professor of psychiatry at University College London (UCL) and author of the rise of autism. She is using the autism criteria in the Diagnostic and Statistical Manual of Mental Disorders (called DSM).

Examples of such behavior range from lack of twists in conversation to completely nonverbal, she said.

She said restrictive benefits and repetitive behaviors are part of the second set of characteristics required to meet the criteria. Thus, such as “hand slapping, swaying or skin picking, but also stick to repeated routines such as eating the same food every day”.

But, is there any evidence that the number of people who meet these criteria has risen?

Ms. Russell led a study that examined changes in the diagnosis rate of autism in the UK over 20 years. It attracts a large sample of data from approximately 9 million patients who are registered in GP surgery.

They found that the new autism diagnosis in 2018 was eight times that in 1998. “It’s a huge increase,” she said, “mostly described as an index.”

This is not only happening in the UK. Although data is lacking in most parts of the world, Ms. Russell said: “In English and European countries where we do have data, there is compelling evidence that diagnosis in other countries has increased similarly to that in the UK”.

But - this is a key point - the number of people increases Diagnosed with autism Not the same as those increase Autism.

Ms. Russell’s research, along with other similar studies, shows that there is a significant increase in the number of people diagnosed with autism, so in this sense there is more autism around them than before. But can the rise in diagnosis be explained by changes to people with autism rather than the increase in the number of people with autism?

The definition of autism is not static. Francesca Happé, a professor of cognitive neuroscience who has been studying autism since 1988, said the earliest research to describe autism occurred in the 1930s and 1940s.

"The original description of autism is to children who need a high support need, usually speaking very late," she said. "Some people don't speak at all. Of course, the focus is on the children, mainly men."

But in the 1990s, when Asperger's syndrome was added to the diagnostic manual, the definition was expanded, Professor Happé said. She said people with Asperger are seen as autistic spectrum because of social difficulties and repetitive behaviors, but with language and good wisdom.

The eight-fold increase in new diagnoses found by Ginny Russell includes Asperger's syndrome, which is considered a specific type of autism.

Another subset of autism added in the manual is "Safety Net Diagnosis", called "Unspecified General Developmental Disorders" (PDD-NOS), which also adds the numbers.

Today, diagnostic manuals refer only to autism spectrum disorder or ASD, including those who have previously been diagnosed with Asperger or PDD-NOS.

The autism network is already wider.

Nowadays, a group of people who often fall under this network are women and girls.

A huge increase in autism diagnosis studies shows that women have a much faster rise than men.

This is the work Sarah Hendrickx saw in part of the team Diagnosing Autism.

"I've been doing this for about 15, 20 years," she said. "In the early days, they were almost all the men diagnosed. Now they're almost all the women I see."

Ms. Hendrickx herself was diagnosed with autism as an adult and is the author of the book "Women and Girls" in the autism spectrum.

She said the significant increase in the number of people diagnosed with autism is because we are “chasing among decades and decades like me.”

Since autism was initially seen as a major impact on boys, she said girls with autism would be diagnosed with mental health conditions such as social anxiety, obsessive-compulsive disorder (OCD) and borderline personality disorder (BPD).

Now, thanks to the increase in research and the increase in MS Hendrickx's, we have a better understanding of how autism performs in girls and women, which was first published in 2014.

One important gender difference, she said, is that girls may be better at covering up, meaning hiding their autistic traits so they can fit socially by copying other people’s behavior.

The diagnosis rate in adults is also much faster than that in children. Ms Hendrickx said this shows another way the autism network is wider: Now, it includes more people with support needs.

“I think we’re talking more about people without intellectual disabilities,” she said. “I think people with delays in speeches are more likely to be diagnosed earlier because the signs are clearer at a very young age.”

There is data to support this. A study showed that between 2000 and 2018, new autism diagnoses for people with mental disabilities increased by 700%. The center of gravity of autism has changed.

This is a good thing for Ellie Middleton, a content creator and author of Autism and ADHD.

The 27-year-old said skeptics questioned the increase in diagnosis should ask: "All of these people spend a lot of time in their lives without diagnosis, without support and disappointment?"

She said she became very uncomfortable before being diagnosed with autism. "I'm using the maximum dose of an antidepressant, which can happen to adults at the age of 17," she said. "I can't be alone, I can't go out."

Her autism diagnosis helped her change her lifestyle three years ago and put her mental health in a better position.

But others are concerned that the autism version now sees distorted public perception in the media and its social media sources.

Venessa Swaby said the focus on celebrities can “charming” autism, who is also autistic and provides support groups for children with autism and their parents through her organization A2NDVOICE. Meanwhile, families with non-speaking autistic children feel “delete”.

As the number of people diagnosed with autism increases, the diversity of autistic people brings in tension about who owns the word, what that means.

There is also a cycle effect: as more and more people are diagnosed with autism, more and more people are aware of this and will further increase the number growth.

The Internet and social media play a major role in this - and guess why the diagnosis is rapidly increasing.

Theories related to the theory that vaccination of measles, mumps and rubella (MMR) are related to the persistence of autism. Others say there must be something in our eating, drinking or breathing that can cause more autism.

However, as we have seen, the data suggest that the increase in diagnosis can be explained by expanding the definition of autism rather than the increase in the number of underlying autism. There are solid research that shows that autism is primarily a product of genes you inherit from your parents.

Is there any evidence that even a minor problem, environmental reasons may play a role in the rise?

Ginny Russell studied different potential environmental factors and found that only a few could explain some of the rise.

“There is definitely a good connection between autism and the age of the parents,” she said. “If the parents are older, you are more likely to have an autistic child, but that’s not a huge effect.”

She also said there is some evidence for "premature birth and infection during pregnancy and some birth complications."

But Ms. Russell said it is important to put these possible factors on the point of view.

“Honestly, I think most of the increase is due to what I call the diagnostic culture,” she said. “Our concept of the condition has changed, which means there is an increase.”

You can listen to the autism curve The BBC sounds now