LONDON — In what may be a perfect formula for helping a well-made TV show go viral, all five episodes of “It’s a Sin” arrived on a British streaming service in late January, on the Friday before a snowy weekend, during a national lockdown.

Since becoming available on HBO Max on Thursday, viewers in the U.S. have been binge watching the show, but in Britain, the show has dominated national conversations over recent weeks.

The drama, created by Russell T Davies, tells the story of a group of friends navigating gay life in 1980s London, as AIDS moves from a whispered American illness to a defining aspect of their young lives. Episodes aired weekly on television on Channel 4, and the show broke records for the channel’s accompanying streaming service, with 16 million streams.

Below is a roundup of how people in Britain have been reacting to “It’s a Sin,” including sharing their own experiences of the AIDS crisis, improving understanding of the H.I.V. treatments available today and lamenting the epidemic’s absence from school curriculums. This piece contains some spoilers.

A critical success

Davies has had a long and celebrated career in British television, including the relaunch of “Doctor Who” and making other hit L.G.B.T.Q. shows like “Queer as Folk” and “Cucumber.”

“It’s a Sin” earned numerous five star reviews from British critics, along with praise for Davies’s writing. In The Telegraph, Anita Singh noted that he makes viewers “care about these characters from the first minute we see them,” adding that “as in so much of his work, he switches seamlessly between tragedy and humor.”

Writing in The Times of London, Hugo Rifkind said, “It is a drama that could only have been made once stories of gay love and gay lives had become an uncontroversial fixture of mainstream popular culture, and it’s obviously thanks in large part to Davies that they have.”

There was also praise for the actors’ performances, and how relatable many of the characters felt. In the TV magazine Radio Times, David Craig saw himself in multiple characters.

“I remember feeling the same timidity as Colin (Callum Scott Howells) when I first attempted to explore my sexuality,” he wrote. “Likewise, I can recall making fraught phone calls home while still closeted, unable to discuss that which was truly weighing on my mind, similar to Ritchie (Olly Alexander).”

Discussions of H.I.V. today

“It’s a Sin” has also sparked a renewed public focus on H.I.V. prevention and treatment. The Terrence Higgins Trust, an H.I.V. and sexual health charity, said it had seen a huge boost in donations through its website, a boost to the number of H.I.V. tests requested at the start of H.I.V. Testing Week and a 30 percent increase in calls to its help line.

“It’s genuinely been phenomenal,” Ian Green, the chief executive of the charity, said in a telephone interview. “It’s rekindled the narrative around H.I.V. in the United Kingdom.”

On the popular daytime show “This Morning” a couple of weeks ago, Dr. Ranj, one of the show’s contributors, took an H.I.V. test live on air. Nathaniel J. Hall, who plays Donald in “It’s a Sin,” talked about living with H.I.V. on the chat show Lorraine. “I’m on medication and my viral load is what is known as undetectable,” he said. “That means I can’t transmit the virus on, so my partner, Sean, remains H.I.V. negative.”

After concerns were raised that the drama could lead to misconceptions around contemporary H.I.V. treatments, Channel 4 now advises viewers after each episode on where to find further information.

A celebration of ‘Jills’

“It’s a Sin” has also sparked praise for the allies of people affected by the disease: friends who visit people in hospital when their families failed to turn up, march in protest and campaign on behalf of H.I.V.-positive people.

The character of Jill (Lydia West) embodies these loyal friends, and is loosely based on a real woman, Jill Nalder, who lived in London in the ’80s and is a friend of Davies. On the show, Nalder plays the character of Jill’s mother. Remembering the period in the Metro newspaper, she wrote: “The L.G.B.T.Q. community ought to be remembered as trailblazers because not only were they fighting for their lives, they were medical guinea pigs — sometimes taking 30 pills a day just to survive.”

“If you are a gay man, I hope you have a Jill,” wrote Guy Pewsey in Grazia.

However, some viewers have been frustrated at the lack of representation of women affected by AIDS in the show. Lizbeth Farooqi, a fictional Muslim lawyer played by Seyan Sarvan, is one example, but is a relatively minor character. “It infuriates me that a lot of coverage of the show has concentrated Jill as the avatar of good womanhood and being this lovely, soft, supportive person,” Lisa Power, a co-founder of the British L.G.B.T.Q. charity Stonewall, told The Guardian. “I want to hear more about the stroppy lesbian solicitor, who most people have not even managed to read as a lesbian.”

Institutionalized stigma

The drama also touches on legislation around the L.G.B.T.Q. community in Britain at the time. In particular, the consequences of Section 28, a 1988 law introduced by Margaret Thatcher’s Conservative government banning teaching that promoted the “acceptability of homosexuality as a pretended family relationship.”

In one scene, Ash (Nathaniel Curtis) is asked to check a school library’s books to make sure they comply with the law, only to find that they did. “I looked at all the vast halls of literature and culture and science and art,” he said. “There is nothing.”

Section 28 was repealed in 2003, but some say its consequences are still being felt in Britain today. Speaking to The Telegraph, Howells, who plays Colin, lamented that the AIDS crisis was not taught in schools. “Why? How? How can this thing happen, literally kill millions of people, and yet they can’t even implement it in education?” he asked.

Some people have also drawn parallels between the stigma that gay, lesbian and bisexual people received in the 1980s and the experience of trans people in Britain today. On Twitter Michael Cashman, another of Stonewall’s co-founders, wrote that some lesbian, gay and bisexual people who lived through that period “are now visiting the same stigmatization, misrepresentation and dehumanization of trans people particularly trans women.”

The power of ‘La’

During the first episode of the show, Ritchie steps in front of a crowd at a house party, dressed in drag, to sing just one syllable: “La!”

“Is that it?” someone in the crowd shouts back. His friends react in hysterics. From that point onward, the characters say “La!” as a greeting and a goodbye. Speaking to “It’s a Sin: After Hours,” an accompanying Channel 4 show, Davies said that “La” was a joke among his friends when he was growing up in Swansea.

Philip Normal, a London artist, decided to make and sell a T-shirt emblazoned with the word, with proceeds going to the Terrence Higgins Trust. “For me, it really underpins the love the characters have in the show and the respect and love that I’ve experienced in the L.G.B.T. community when I moved to London as a young gay man,” he said in a telephone interview.

He said he had now raised £200,000 for the charity, adding: “I didn’t think it was going to take off! I thought I would sell, like five.”