Infectious disease affects millions of people each year, causing many deaths. The No. 1 killer in the world for a number of years, infectious disease has been downgraded to No. 2 only recently by cardiovascular disease. That doesn’t mean the need for laboratory testing has gone down, in fact it’s increasing and expanding beyond diagnosis.

AIDS on the rise in United States
AIDS cases in the United States had been declining for several years, but on May 31st, the Centers for Disease Control and Prevention (CDC) reported that an “alarming” rise had occurred in the rate of HIV infection among young gay and bisexual men.

Kelly Westfall, industry analyst for clinical diagnostics at Frost & Sullivan in San Antonio, Texas, estimates that the U.S. market for HIV testing is $365 million and growing at a 15 percent CAGR (compounded annual growth rate). The market breaks down as shown in the chart below.

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Source: Frost & Sullivan

A Frost & Sullivan report on the U.S. HIV Diagnostics and Monitoring Markets noted that “Decentralization of HIV viral load monitoring and its extensive usage in hospitals and reference laboratories are major market drivers. While a high degree of public awareness promotes screening, the increasing AIDS patient population and their improving life expectancies ensure continued demand.”

HCV the No.1 reason for liver transplants
The hepatitis C testing market is experiencing double-digit growth. The risk of contracting HCV from blood transfusion is small; nonetheless the CDC estimates that there are 3.9 million infected individuals in the United States. Almost 80 percent of these individuals do not know that they are infected. The need to test within this population is growing, and diagnostics manufacturers are responding to that growth.

Hepatitis testing becoming easier
Ortho Clinical Diagnostics offers three hepatitis markers on its Vitros immunodiagnostics system: 1) the hepatitis B surface antigen, which is the highest volume marker overall; 2) the anti-HBs, which tests for immunity against hepatitis B; and 3) anti-HCV. “Until we introduced these three assays on the Vitros platform, these tests were performed using manual techniques on an ELISA plate and were four- to six-hour procedures. We are the only U.S. manufacturer that can offer all three assays on a random access immunodiagnostic system with a broad menu,” said Michael DeLucia, product director of Infectious Diseases at Ortho Clinical Diagnostics in Raritan, N.J.

These three markers comprise around 70 percent of the hepatitis marker volume in diagnostic testing. “With our three assays, we enable hospitals to do the testing themselves and make it much easier. Just put a barcoded test tube onto the analyzer, and you get the result in less than an hour. It enables hospitals that never did this type of testing in-house to keep that testing in-house,” said DeLucia.

DeLucia predicts that this market will continue to expand especially with HCV screening and monitoring of new therapies. Ortho is developing a new test for HCV core antigen. “This test will enable physicians to monitor viremia, improving patient management. The immunoassay will be easier to perform than current complex methods,” he said.

HIV and hepatitis testing are moving into clinical hospital labs
The worldwide market for non-molecular infectious disease testing approaches $1 billion and is growing at about 8 percent a year, according to Stephen Weiss, director of immunodiagnostics marketing at Bayer Diagnostics in Tarrytown, N.Y. Byron Hewett, vice president of marketing for the Laboratory Testing Segment of Bayer, noted that this market includes tests such as rubella, toxoplasmosis and CMV, but that the bulk of the dollars are in hepatitis and retroviral testing.

In June, Bayer acquired the rights to pursue the development, manufacturing and distribution of immunoassays for hepatitis C, HIV, and hepatitis A and B. “We are a prominent leader in the immunoassay area in general, and this is the other big part of the immunoassay market,” Weiss said.

Hewett added, “For the most part, these assays have been semi-automated, and for years people have been looking for fully-automated random-access capability with these types of assays. Adding these tests to the Advia Centaur menu will allow us to deliver that capability to the marketplace and allow our current customers to broaden the capability and variety of their menu.”

The immunoassays will be available in 2002 and 2003. Weiss expects that labs that don’t do hepatitis and retroviral testing will start, because it will be much simpler for them. He predicts that labs currently using more laborious methods will switch. “We see a gain on both sides, and there’s a broad market of customers both in private and hospital laboratories,” he said.

Nucleic acid diagnostics monitors therapy
Bayer also offers bDNA-based assays for HIV-1 RNA, HCV-RNA and HBV-DNA. An HCV-RNA qualitative test, currently in development, uses TMA (Transcription-Medicated Amplification) to detect the presence of the virus. The HIV and HCV viral load assays are based on the most recent version of the bDNA technology, and Bayer has the No. 1 or No. 2 market position globally, according to Mike Barcellos, director of global marketing for the Nucleic Acid Diagnostics Segment of Bayer Diagnostics in Emeryville, Calif.

Bayer signed an agreement with Belgium-based Innogenetics to offer genotyping assays for HIV and HCV based on their LiPA technology. “We offer multiple technologies because the technologies have different capabilities, different strengths. We’ve chosen the ones that best address the specific needs of HIV and HCV testing. The LiPA tests are qualitative and user-friendly,” said Barcellos.

“We are the only company offering a portfolio of HCV molecular diagnostic tests. In HIV, next year we’ll be launching an HIV resistance test that will position us as the only company supplying both resistance and viral load assays. Once we have the HIV and HCV assays in the immunodiagnostics market, I predict that Bayer will be in a unique position,” said Barcellos.

Keeping up with viral mutants
“Abbott Diagnostics has been offering tests for infectious disease since 1972, starting with hepatitis testing,” explained Jim Koziarz, Ph.D. and vice president of research and development at Abbott Diagnostics in Abbott Park, Ill. Since ‘72 the company has expanded its hepatitis testing menu and put those tests on different instrument platforms. Abbott also has expanded into sexually transmitted disease and HIV testing. “We have invested a substantial amount of R&D resources in improving those types of tests and in the future — we intend to continue doing that,” said Koziarz.

As a result of that research, Abbott has garnered headlines for discovering new hepatitis viruses such as GBV-C. “There appears to be some correlation between GBV-C and HIV,” said Koziarz. “By itself, GBV-C does not cause symptoms, but co-infection with HIV results in a better prognostic outcome for the HIV patient. The impact of this information for the HIV patient remains to be seen, but it is one example of the ongoing discovery work done at Abbott Labs.”

Another area of study for Abbott is hepatitis B virus mutations and the capability of its diagnostic tests to detect mutants. “We think that’s important,” said Koziarz. “We are committed to giving customers the broadest detectability, so that no hepatitis B infection goes undetected. In HIV, we’re making sure that our tests have the broadest range of detectability for all the HIV mutations. That research is ongoing. You can’t have a test that looks at only one viral subtype; that is too narrow a focus. Our strategy has always been to look at viral strains from different parts of the world, to make sure that we have the widest possible detectability.”

Abbott is automating its entire product line for hepatitis virus and retroviral testing. The task already is completed outside the United States, and they are awaiting FDA approval in the United States. “The Prism instrument, once it is introduced in the United States, will offer an HIV test that will have the broadest detectability of any available serologic test for HIV, according to internal and external data we have collected,” said Koziarz. “These efforts ensure that no potential infectious agents will get through the screening process.”

ID testing in the future
For the next five years, HCV and HIV testing will comprise more than 80 percent of the infectious disease market. “There isn’t going to be another HCV or HIV that any of us can predict. The next big area is probably going to be outside infectious diseases,” Barcellos said.

Koziarz forecasts more testing for emerging infectious agents such as prions and nvCJD, two other areas already being researched at Abbott.

When you add the current HIV and hepatitis epidemics to the nightly news reports of bioterrorism, the only thing that seems constant about infectious disease testing is change.

Jan Hodnett is a freelance writer in Rye, N.Y.