Connect with us

Published

on

By Dr. Priyom Bose, Ph.D. Reviewed by Danielle Ellis, B.Sc.

What happens after HIV infection?
Evolution of HIV diagnostic assays
Conclusions
References
Further reading

Acquired immunodeficiency syndrome (AIDS) is caused by the human immunodeficiency virus (HIV) that attacks the body’s immune system, making it vulnerable to all infections. One of the major concerns of the early AIDS epidemic that began in 1981 was the lack of proper diagnostic measures to identify infected individuals.1 Since the development of the first HIV diagnostic assay in 1985, scientists have continued to improve diagnostic accuracy, detection speed, and cost.

Image Credit: Hanna Karpiak/Shutterstock.com What happens after HIV infection?

The immune system produces antibodies after encountering harmful foreign substances or antigens. HIV infects the vital cells associated with immunity, such as macrophages, helper T cells, and dendritic cells, and disrupts their function. The three important HIV antigens are p24, gp 41, and gp 120.2

HIV is a slow-replicating retrovirus that is transmitted through sexual intercourse, sharing an infected needle, or by blood transfer.3 After HIV infection, the viral load cannot be measured immediately due to low plasma load. Typically, the viral RNA can be measured within 10 to 12 days after infection.4

Antibodies to p24 and gp 41 are the first serological markers used to detect HIV infection. IgG antibodies appear approximately three weeks after infection. In the majority of HIV-infected individuals, HIV antibodies appear to circulate within 1 to 2 months of the infection. However, in a few cases, it may take up to six months to appear at a detectable level.5 Evolution of HIV diagnostic assays

Over the years, scientists have developed many immunoassays and nucleic acid amplification tests (NAATs) to accurately and high-throughput HIV diagnosis. These tests are broadly divided into two categories, namely, screening and confirmatory tests. Typically, HIV tests are performed on blood, oral fluids, or urine samples.6

HIV screening is performed by various immunoassays that focus on detecting IgG antibodies against HIV-1 antigens in the serum. Techniques such as Western blot, line immunoassay (LIA), and recombinant immunoblot are used as confirmatory tests.7 Some of the important HIV diagnostic assays are discussed below: Serological testing for HIV

In the mid-1980s, simple serological tests for HIV antibodies were developed based on culture-derived viral antigen preparation.7 These tests enabled HIV diagnosis and assessed blood and blood product supplies. Since the early assays, various serological assays have been developed that aided simple/rapid testing, high-throughput screening, confirmatory tests, incidence determination, and epidemiological surveillance. Since its first development, five generations of enzyme immunoassays (EIAs) have emerged based on varied antigen preparations and detection chemistries.8

First-generation assays: The first-generation EIAs detect IgG antibodies from antigens derived from whole viral lysates of HIV-positive cultures. Since crude antigen lysate contains impurities, this method exhibited reduced specificity and high false positivity. In contrast, immunofluorescence assays or Western blotting (WB) have shown higher specificity and lower false positivity.

Second-generation assays: Second-generation assays involve the use of recombinant proteins or synthetic peptides derived from the immunodominant regions (IDR) of HIV-1 proteins and gp36 of HIV-2, which increases sensitivity and decreases false positivity.

Third-generation assays: Third-generation assays, including the Genetic Systems HIV-1/HIV-2 Plus O EIA, use a variety of antigens to detect HIV-1 and -2 antibodies in the serum. A major advantage of third-generation sandwich format assays is their ability to detect HIV-1 IgM antibodies early, enabling quicker HIV diagnosis.

Fourth-generation assays: The fourth-generation EIAs, including the Abbott Architect HIV Ag/Ab Combo assay, utilize fully automated chemiluminescent microparticle technology that can instantaneously identify antibodies to HIV-1 and HIV-2 and HIV-1 p24 antigen. This technique has further allowed early HIV diagnosis. Other advantages of fourth-generation high-throughput assays are their capacity to perform more than 150 tests per hour and their ability to test specimens immediately upon arrival and generate results within 30 minutes.  These assays are suitable for facilities, such as blood banks, that handle high volumes of blood samples.

Fifth-generation assays: Fifth-generation assays, such as the Bio-Rad BioPlex 2200 HIV Ag-Ab assay, use magnetic beads coated with p24 monoclonal antibodies and epitopes specific for HIV-1 and HIV-2. This type of assay has a major advantage in  that it can confirm HIV infection in a single test. Interested in Assay Kits? Explore Equipment Here

Despite the advancements in EIA assays, the challenges associated with the generation of false positive results persist. Therefore, EIA-reactive specimen is typically retested with supplemental tests, such as Western Blot. Rapid diagnostic tests Related StoriesSweden exceeds UNAIDS HIV goals but faces new challengesNutrition's pivotal role in combating tuberculosis: addressing N-AIDS for better outcomes

The first HIV rapid test was available in the early 1990s. It determined an individual's serostatus before surgery, maternal labor/delivery, and organ transplant. Rapid diagnostics is based on immunochromatographic technology that uses blood from finger pricks to assess HIV status. 9 This test can provide results in less than 30 minutes and can be used in point-of-care (POC) settings. Since this test presents both false positive and negative results, it is essential to confirm the findings with laboratory-based HIV assays.

The main advantage of this technique is that any non-laboratory staff can perform it in a primary health care center. Even though decentralization of HIV diagnostic services has increased HIV test service in remote areas, it has been challenged by the lack of national guidelines, waste disposal, inventory management, and quality assurance (QA) monitoring.10

HIV self-testing, based on rapid testing methods, has allowed individuals who would otherwise refrain from testing in fear of discrimination to perform the test privately and start proper intervention. The World Health Organization (WHO) has prequalified several HIV rapid tests for HIV self-testing, including the Insti HIV-1/HIV-2 antibody tests and the Oraquick rapid HIV-1/2 antibody test.10 Nucleic acid test (NAT)

The NAT identifies HIV nucleic acid, i.e., either RNA or proviral DNA, in the blood sample. This test is based on the principles of polymerase chain reaction (PCR), nucleic acid sequence-based amplification, or ligase chain reaction.11 This test has proved to be vital in situations when an antibody against HIV is absent in serum. NAT is also performed in newborns of HIV-infected mothers. Unlike other assays, this test can detect HIV even after recent or possible exposure to the virus. Furthermore, NAT can quantify viral load.

Revolutions in Infectious Disease Testing Conclusions

The advancements in HIV diagnostic assays have played a vital role in identifying, staging, and monitoring infected individuals, even when they are under antiretroviral therapy. These assays have played an important role in surveillance and identification of transmission hot spots. Extraordinary progress in HIV testing methodologies has not only reduced false positives but decreased assessment time as well. References Sharp PM, Hahn BH. Origins of HIV and the AIDS pandemic. Cold Spring Harb Perspect Med. 2011;1(1):a006841. doi: 10.1101/cshperspect.a006841. Foster JE., et al. Viruses as Pathogens: Animal Viruses, With Emphasis on Human Viruses. Viruses. 2018; 157-187. doi.org/10.1016/B978-0-12-811257-1.00007-3 Dasgupta A, Wahed. Human immunodeficiency virus (HIV) and hepatitis testing. Clinical Chemistry, Immunology and Laboratory Quality Control (Second Edition). 2021; 513-533. doi.org/10.1016/B978-0-12-815960-6.00015-7 Konrad BP, et al. On the duration of the period between exposure to HIV and detectable infection. Epidemics. 2017; 20, 73-83. doi.org/10.1016/j.epidem.2017.03.002 Davis LE. Acute viral meningitis and encephalitis. Infections of the Nervous System, 1987; 156-176. doi.org/10.1016/B978-0-407-02293-5.50014-3 Pant PN. Oral fluid-based rapid HIV testing: issues, challenges and research directions. Expert Review of Molecular Diagnostics. 2007; 7 (4), 325-328, DOI: 10.1586/14737159.7.4.325 Abdullah DM, et al. The contemporary immunoassays for HIV diagnosis: a concise overview. Asian Biomed (Res Rev News). 2023;17(1):3-12. doi: 10.2478/abm-2023-0038. Alexander TS. Human Immunodeficiency Virus Diagnostic Testing: 30 Years of Evolution. Clin Vaccine Immunol. 2016;23(4):249-53. doi: 10.1128/CVI.00053-16. Aidoo S, et al. Suitability of a rapid immunochromatographic test for detection of antibodies to human immunodeficiency virus in Ghana, West Africa. J Clin Microbiol. 2001;39(7):2572-5. doi: 10.1128/JCM.39.7.2572-2575.2001. Parekh BS, et al. Diagnosis of Human Immunodeficiency Virus Infection. Clin Microbiol Rev. 2018;32(1):e00064-18. doi: 10.1128/CMR.00064-18. Garrett, P. E. Quality control for nucleic acid tests: Common ground and special issues. Journal of Clinical Virology. 2001; 20(1-2), 15-21. doi.org/10.1016/S1386-6532(00)00150-5

Further ReadingAll HIV ContentThe Economic Impacts of AIDSRecent Advancements in Treating HIV

Last Updated: Nov 29, 2024

Continue Reading

Sports

A famous dad, the perfect swing and elite Fortnite skills: Meet MLB’s most fascinating hitter

Published

on

By

A famous dad, the perfect swing and elite Fortnite skills: Meet MLB's most fascinating hitter

Warning: What you’re about to read is Jacob Wilson‘s opinion. He is a professional baseball player — a very good one — and not a medical expert, but there are some things he is convinced are true, and this is one of them.

The 23-year-old Wilson, the Athletics’ wunderkind shortstop, is wise enough to understand that the sort of success he has found on the baseball field — a .347 batting average and a near-certain invitation to the All-Star Game coming — comes from a multitude of areas. He is the son of a longtime big leaguer, so certainly genetics helped, and he works relentlessly at his craft, which goes a long way. But the special sauce that built the American League Rookie of the Year favorite, he believes, included a secret ingredient.

Fortnite.

“Kids are going to love this one. Parents are going to hate me,” Wilson said. “I am a big believer in video games. It’s fast decision-making strategy. I think that gets me ready for the game, because when you’re in the box, you have to process a lot. So there’s some days where I’ll wake up and I’ll play video games and then I’ll go to the field, and I’ll have a good day. Some days I won’t play and don’t see the ball well. I think it really helps me train kind of the decision-making that I have to make six, seven hours later at the baseball field.”

Yes, one of the best hitters in the major leagues, a contact maven who strikes out with the infrequency of Tony Gwynn, swears that he’s as good as he is at a kid’s game because of his aptitude at another kid’s game. After Wilson wakes up, he deploys to his living room and parks in a chair. On the table in front of him sit a PC and a controller. He logs in to Fortnite — the 8-year-old game still played by millions every day — hops on the Battle Bus and systematically disposes of those with the misfortune of sharing a map with him.

“If we play a game with me and him and guys we know and you kill him once, you’re like, ‘That’s a good day,'” A’s infielder Max Muncy said. “You could play 50 rounds. Just once is good.”

Muncy has known of Wilson’s Fortnite exploits since they were teammates at Thousand Oaks (California) High, where Wilson’s father, former Pittsburgh shortstop Jack Wilson, coached. Back then, Jack actually questioned whether the game was interfering with Jacob’s baseball growth — though he understood his son’s reasoning. Over his 12-year big league career, Jack earned a reputation as one of the best pingpong players in the major leagues. It was pure reaction, not unlike hitting, and he complemented his pregame work in the batting cage with the brain training found in a paddle and hollow ball.

He saw the same opportunity in video games for his son — with a caveat.

“I do believe in the hand-eye coordination that video games give — as long as you do your homework,” Jack said. “Kids, if you’re reading, do your homework.”

The Wilsons are not alone in their belief that unconventional methods off the field can lead to success on it. Studies back up the suggestion that video games can be beneficial for brain activity. And considering the recognition being lavished on Jacob Wilson — he is more than a quarter-million votes ahead of Kansas City star Bobby Witt Jr. in All-Star balloting to be the American League’s starting shortstop — the benefits can be pronounced.

Of course, dropping into Anarchy Acres does not a big league hitter make. The story of Wilson’s ascent actually starts in his backyard, where he spent countless hours figuring out how to thrive in a game that simply isn’t built for hitters like him anymore.


Heaven for the Wilson family is a regulation-sized turfed infield with a FungoMan ground ball machine, a fence covered with famous retired numbers and stadium logos, a full dugout on the third-base side — and a grill stationed in center field in case someone gets hungry. The backyard of the family’s home is a testament to form and function, and it’s where Jacob learned how to be — and how not to be — like his father.

“It was a place built for guys who just love the grind of wanting to get better every day,” Jack said.

Jack’s bat was never as adept as his glove, and to last a dozen years in the big leagues, he needed countless reps to keep his fielding at a level that, according to Baseball-Reference, produced the fifth-most defensive wins above replacement this century, behind only Andrelton Simmons, Yadier Molina, Adrian Beltre and Kevin Kiermaier.

“You know that idea about being able to write a letter to your former self on what would you tell yourself now?” Jack said. “I get to do that with Jake. And I said, ‘You know, this is the way I hit. I don’t want you to hit like this.’ Because there were so many things I wish I could have done differently. If I were to build a perfect hitter, what would I do?”

He started with Miguel Cabrera. Wilson always admired how tall he stood in the batter’s box before sinking into his legs. Then it was Mike Trout. The simplicity of his swing has always been a marvel, but in particular Wilson appreciated the speed at which he loads his hands, allowing Trout to be on time even for 100 mph fastballs. The final lesson was Albert Pujols’ bat path, which was so flat and stayed in the zone for so long that it allowed him to sting the ball from foul pole to foul pole while maintaining strikeout numbers that were well below league average.

To hone that Voltron of a swing, a teenage Wilson would grip a custom wood bat with a 1½-inch barrel — an inch less than a standard big league barrel — and face his dad, who stood 45 feet away and ripped 85 mph fastballs and sliders using a tennis ball. If he didn’t catch the ball on the meat of the barrel, it would spin sideways, forcing him to learn to maneuver his bat with special dexterity.

The skinny bat made a regulation-sized model feel twice as big. When he took regular batting practice, Jacob always started by peppering the right side of the field on his first dozen swings. Even though Jacob was bigger than his father — at 6-foot-3, he is a comparatively imposing presence — Jack didn’t want him to fall into the trap of always trying to pull the ball. While that approach works for some hitters, Cabrera, Trout and Pujols embraced and embodied an all-fields approach.

By Wilson’s junior year in high school, the work started to pay off. Wilson didn’t strike out once all season. He didn’t punch out during his COVID-shortened senior season, either, then continued that trend at Grand Canyon University in Phoenix, where his sophomore year he whiffed seven times in 275 plate appearances and his junior season had five punchouts in 217 times at the plate. Twice, he received a plaque from the NCAA for being the toughest hitter to strike out in college baseball.

The A’s took Wilson with the sixth pick in the loaded 2023 draft. Last year, he hit .433/.473/.668 with just 15 strikeouts in 226 plate appearances across three minor league levels and, just a year and 10 days after being drafted, he debuted in the big leagues.

In a world of launch angle and exit velocity, Wilson arrived in the majors wanting to be more like Luis Arráez and Nico Hoerner, contact artists nonpareil who value batting average and are allergic to strikeouts.

“I just take strikeouts so personally,” Wilson said. “It’s the one thing in this game that makes me more mad than anything. So I’ll go up there and I’ll swing at a pitch that’s maybe a couple inches off and take a base hit to right. So I think batting average definitely is a stat that should be seen and should matter for most hitters.”

Wilson’s swing is kinetic, with a wide-open stance that closes as he moves his legs and flaps his arms — a little Chicken Dance, a little Cabrera-Trout-Pujols. While he hasn’t always been this twitchy — “I’ve got to keep my muscles moving a little bit,” Wilson said — it works for him. He keeps the knob of the bat in the direction of the ball longer than most hitters, reminding himself to “stay inside the baseball,” a lesson preached ad nauseam by Jack. Aiming to strike the inside of the ball, Jacob said, keeps him from rolling over it. He lives by the old axiom “good hitters get jammed” and doesn’t shy away from flipping a duck snort between the infield and outfield.

The approach has served him well. After starting the year in the No. 9 hole, Wilson has hit first or second every game since May 7. Only Arráez has a lower strikeout rate than Wilson’s 6.8% — and Wilson has nine home runs compared with Arráez’s one. Of all the strikeout-averse hitters in the game, the one with a line most comparable to Wilson’s.347/.388/.487 is Cleveland third baseman Jose Ramirez, who is primed to play in his seventh All-Star Game this season.

“It’s not even his hits,” said Nick Kurtz, the A’s first baseman and fellow rookie. “I’ve seen multiple times where there’s a sinker up and in that was going to hit him, and he hit it to second base. Sometimes they’re a hit, sometimes they’re not. Every time, though, I’m like, ‘How the hell did he do that?’ Being able to touch it, not break your bat and go the other way with it? I’m at a loss for words.”


On April 5 at 11:13 p.m., Jack Wilson’s phone dinged. He had texted his son to congratulate him on a good team win by the A’s. Jacob didn’t want to hear it. He was mad. He had gone 1-for-4 with a two-run double, but that wasn’t good enough.

“I’m not a .250 hitter,” Jacob texted.

Jack laughed. He batted .265 in his career. It was enough to earn him more than $40 million playing. His son wants to be better — not because he’s greedy but because he’s capable of it.

“That’s a good thought process,” Jack said. “Because when I was a rookie and I got a hit, I was pumped. I always tell him, ‘Man, hitting is freaking hard.’ It’s just not going to be every day where your swing is on point and you match up. It’s just the way it is. So this has been a real learning experience. And it will be for a long time. The more he learns now, the better off he is in the future and hopefully spends a long time as an Athletic.”

The A’s are counting on their star shortstop as a linchpin of their impressive offensive core. Wilson is the fulcrum, Kurtz the powerhouse with a propensity for late-inning heroics. Designated hitter Brent Rooker and outfielder Lawrence Butler are both sluggers locked up to long-term deals. First baseman Tyler Soderstrom and catcher Shea Langeliers provide additional home run thump. Denzel Clarke is going to win multiple Gold Gloves in center field. If they can build a pitching staff to match, the team scheduled to move to Las Vegas for the 2028 season will be among the most exciting in baseball.

And it all starts with the kid who is definitely not a .250 hitter and definitely does take strikeouts personally.

“I mean, I’ve studied his swing,” Muncy said. “There’s things that he does so well that other guys don’t do that leads to that. And I think one of the things is probably just his mentality. He has always thought he could put it in play. I don’t think there’s ever been a guy where he is like, ‘I can’t put it in play.’ When you have that supplemental edge — I can put it in play no matter what — that helps.”

Every edge helps, be it bat-to-ball skills, burgeoning power or the ability to no-scope someone from 300 meters. Wilson has no plans to abandon his Fortnite reps. It’s part of his training now, and even if it doesn’t work for everyone, he sees Victory Royales leading to victories for the A’s.

“Everybody has their own approach and everybody’s here for a reason,” Wilson said. “This is the big leagues. Everybody is the best in the world at what they do.”

Continue Reading

Business

Trade war: UK car exports to US halved in May ahead of truce

Published

on

By

Trade war: UK car exports to US halved in May ahead of truce

The extent of the harm inflicted on UK car exporters from US tariffs has been revealed, with shipments plunging by more than half last month according to industry figures.

The Society of Motor Manufacturers and Traders (SMMT) said the number of UK-made cars heading across the Atlantic fell 55.4% during May following a decline of just under 3% the previous month.

The dramatic slowdown marked a reaction to the 25% tariffs imposed on imports by the Trump administration from 3 April amid the president’s “liberation day” trade war escalation which sparked chaos in global supply chains.

The move prompted Jaguar Land Rover – the biggest exporter of cars to the US from these shores – to suspend all shipments temporarily.

Please use Chrome browser for a more accessible video player

April: Jobs fears as JLR halts US shipments

The US is the most important market for UK producers, in value terms, and was worth £9bn last year with the vast majority of those sales coming from luxury brands also including Bentley, Rolls-Royce Motor Cars and Aston Martin.

Tariffs on UK-made cars imported into the US have since been reduced from 25% to 10% for up to 100,000 vehicles on an annual basis.

That was signed off by the president 10 days ago.

More from Money

While it spares UK producers from the worst, the US trade war does not represent the only challenge.

Please use Chrome browser for a more accessible video player

Explained: The US-UK trade deal

The industry has been crying out for help to bolster its competitiveness and increase demand for new electric vehicles amid lacklustre interest, not just at home, but abroad too.

It has welcomed promised help with punitive energy costs through the government’s industrial strategy.

Wider SMMT figures showed car and commercial vehicle production fell for the fifth consecutive month in May.

It reported a 33% decline to just 49,810 vehicles and said it was the worst performance for May, when the COVID years were excluded, since 1949.

The industry body blamed continuing model changeovers, along with the impact of US tariffs.

The number of vehicles produced for the domestic market fell while shipments to the EU, which generally accounts for the biggest share of volumes, was down by 22.5%.

Read more:
Industrial strategy targets short-term pain for long-term gain

Mike Hawes, the SMMT’s chief executive, said: “While 2025 has proved to be an incredibly challenging year for UK automotive production, there is the beginning of some optimism for the future.

“Confirmed trade deals with crucial markets, especially the US and a more positive relationship with the EU, as well as government strategies on industry and trade that recognise the critical role the sector plays in driving economic growth, should help recovery.

“With rapid implementation, particularly on the energy costs constraining our competitiveness, the UK can deliver the jobs, growth and decarbonisation that is desperately needed.”

Continue Reading

UK

Post Office: Police identify seven suspects related to Horizon scandal

Published

on

By

Post Office: Police identify seven suspects related to Horizon scandal

Police investigating the Horizon Post Office scandal have now identified seven suspects, with more than 45 people classed as “persons of interest”.

A “scaled-up” national team of officers has been in place for over six months as part of Operation Olympos – dedicated to looking at crimes related to the Horizon Post Office scandal.

The number of suspects has increased to seven since before Christmas, as part of a UK-wide investigation involving 100 officers.

Four have now been interviewed under caution.

Hundreds of subpostmasters were wrongfully convicted of stealing after faulty computer software created false accounting shortfalls in Post Office branches between 1999 and 2015.

Commander Stephen Clayman, Gold Command for Operation Olympos, described a “huge shift” in terms of their investigation and “significant progress”.

Commander Stephen Clayman
Image:
Commander Stephen Clayman

“We’ve got over four million documents that are going to rise to about six million documents,” he said, “but we’re beginning to methodically work through those and looking at individuals who are associated with certain prosecutions.”

More on Post Office Scandal

He described a “pool of about 45 people plus” classed as “persons of interest”, with that number “expected to grow”.

He added that officers have questioned “some” in the past and “more recently” and are looking at the offences of perverting the course of justice and perjury.

The “wider pool” of persons of interest is made up of Post Office investigators, lawyers, and “management” across Fujitsu and the Post Office.

Please use Chrome browser for a more accessible video player

Post Office knew about faulty IT system

The team of officers will be identifying actions which could amount to criminal offences on both an individual and corporate basis.

Any decisions made on whether to charge will not happen until after the Post Office inquiry findings are “published and reviewed”.

The Operation Olympos officers are part of four teams – a London hub and three regional teams – who have been described as “highly motivated” across England and Wales.

Police Scotland and the Police Service of Northern Ireland are also helping.

Cmdr Clayman said that officers “will be building a robust case” to pass on to the Crown Prosecution Service.

Operation Olympos
Image:
Officer working in one of the four Operation Olympos teams

He also added that, compared to the inquiry, his officers will have to “prove this to the criminal standard…a much, much higher standard”.

He described feeling “optimistic” and “confident” that the teams will have “some successful outcomes”, and said they are “working as hard and as quickly as (they) can”.

Teams are involved in what has been described as a “focused strategy which gets to the heart of the issues”.

Their investigations are being overseen by the National Police Chiefs’ Council and the Metropolitan Police.

Read more from Sky News:
Pornography sites to introduce ‘robust’ age verification
Salmonella cases reach highest levels in a decade

Victims have also been told that the police will not be reinvestigating every case but “taking a speculative look at cases” to focus on key people involved and evidence for prosecution.

Operation Olympos is also making use of special software to help process the amount of evidence to sift through material in relation to key events and identified cases.

Of the four suspects interviewed under caution, two were questioned in late 2021, one in late 2024 and the most recent in early 2025.

Continue Reading

Trending