The Laboratorian - Volume 4, Issue 2

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The Laboratorian - Volume 4, Issue 2
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October 2012 - Volume 4, Issue 2

Article Index

- West Nile Testing
- Gen Probe Testing
- Lab Building Named

Editorial

Up here on the seventh floor, life isn’t glamorous, especially compared to the rest of the laboratory. We don’t save lives in nearly as tangible a way as many of the other groups in the laboratory. We’re not saving babies from debilitating genetic diseases, we’re not keeping tabs on outbreaks of mosquito- borne disease like West Nile, and we’re not preparing to protect the public from devastating biological or chemical attack. We just humbly test drinking water, day in and day out.


Water testing is not an exciting endeavor, but it is an important one. It’s certainly not a fast changing field. The Safe Drinking Water Act was passed in 1974 and has seen major updates only twice since then – in 1986 and 1996. It is the federal law that governs the quality of drinking water. It outlines the permitting process and defines maximum contamination limits, how often things should be checked and who should be checking. In short, it covers everything involved with drinking water. If you speak legalese and are interested in an afternoon of torture, you can check the Code of Federal Regulations, Title 40, parts 141-143.

The responsibility for monitoring water quality pretty much falls to the states, and in Texas, this is done by the Texas Commission on Environmental Quality (TCEQ). They are tasked with monitoring water quality in accordance with The Safe Drinking Water Act. The TCEQ contracts with the DSHS Laboratory to do some of the testing; the rest is contracted out to the Lower Colorado River Authority (LCRA).

Here at the Laboratory we do a number of tests for organic, inorganic, biological and radiological contaminants. Personally, I can only speak specifically about organics testing, because that is what I do. In organics we test for volatile and semi-volatile organic hydrocarbons, many of which are industrial byproducts, pesticides and herbicides that have the potential to cause cancer and disrupt human endocrine systems. We also test for disinfection byproducts, such as trihalomethanes and halo acetic acids, which are produced by chemical reactions that take place during the cleaning process.

Samples are extracted (or purged) and analyzed using a Gas Chromatograph coupled with a Mass Spectrometer or an ECD or by Liquid Chromatography and positive results are reported at concentrations often less than one part per billion.

Under normal circumstances, there is very little risk of acute toxicity when it comes to drinking water, but the real potential for harm comes from chronic exposure to low concentrations of chemicals over a long period of time. The Environmental Protection Agency (EPA) has established Maximum Contamination Limits for specific compounds, based on toxicology studies indicating safe levels of exposure and taking into account the amount of exposure a normal person consuming a normal amount of water over time would experience. The EPA must determine whether a compound adversely affects human health, is likely to be found in public water systems at harmful levels, and if regulation represents an opportunity for meaningful health risk reduction. In addition to the federally regulated compounds, other compounds are monitored, partly to find out whether certain chemicals are relatively common in drinking water and whether they should be considered for regulation in the future.

So what’s new on the horizon? Pharmaceuticals. The media has shown some interest in pharmaceuticals in drinking water, and rules are being put in place to regulate their disposal. They are a cause for concern because we know they are biologically active at low levels – after all, that’s the way they are designed. This is compounded by the fact that we live in an aging society that consumes increasingly large amounts of pharmaceuticals. Sooner than later, pharmaceuticals will probably be added to the list of compounds we currently look for.

When people find out that I test drinking water, they often ask me if tap water is safe to drink. I generally give them a qualified yes. I drink it on a daily basis. I don’t run screaming from the water fountain. I do use a filter at home – attached to the kitchen faucet. To be honest though, I don’t think I have ever analyzed a sample that exceeded the maximum contaminant level. However, I know there can be traces of chemicals lurking, and I know there may be chemicals that we don’t know to look for yet. I’d just as soon remove as much as possible, if it doesn’t come at a great cost to me. When I turn on the tap, I trust that the water is safe to drink, but when I have the chance, I like to make sure it’s extra safe.

by Andrew Vineyard

Laboratory Testing Key in West Nile Virus Surveillance

Laboratorian placing cell cultures under the microscope to check for evidence of West Nile virus

Being the first to know isn’t always what it’s cracked up to be. As key investigators in public health response, laboratorians are often the first to know about outbreaks. “We knew in late May that it was going to be a bad year for West Nile – one month earlier than we usually begin testing and long before West Nile was in the news,” said Joanne Day, a microbiologist in the DSHS Arbovirus Laboratory. By July, everyone involved in West Nile Virus (WNV) testing was working overtime. From mosquito speciation to virus identification, each person on the laboratory team does what it takes to get needed results. “I’m the workhorse,” Ms. Day said as she described team member roles that range from species identification of live mosquitos to interfacing with investigating epidemiologists and submitters.

Zoonosis refers to any infectious disease that can be transmitted between species. Viruses are no exception. In the case of WNV, transmission is often between a bird and a human. The vector, or carrier, is a mosquito. Because of this, specimens take two forms: live mosquitos, which are tested in the Arbovirus Laboratory, and human serum and cerebro spinal fluid (CSF), which are tested by the Serological Analysis group. Testing and

Close-up of a mosquito in the Arbovirus Laboratory

surveillance are important, because there is no anti-arboviral therapy and no vaccine. “Up to 80 percent of people infected with West Nile virus will have no symptoms and will recover on their own, however, some cases can cause serious illness or death,” according to the official information on West Nile Virus in Texas.

“The sheer volume has been extremely unusual,” said Shelley Stonecipher, DVM, MPH, a Zoonosis Control Veterinarian involved in investigating West Nile cases. Her fax machine eats through reams of paper as she receives laboratory reports and clinical information. “The case definition calls for both the clinical and laboratory information…. If we don’t have the proper information or only have the lab result, they will not be counted as a case,” Dr. Stonecipher said. That’s the easy part. The rest of the epidemiologist’s investigation involves retrieving patient location information – either from the Laboratory report or from the physician – and routing the case to the appropriate investigator. The investigator must contact the family to fill out a case report form, which includes information from symptoms, if any, to travel history. Travel information is important, because cases are reported by residence but “that doesn’t necessarily mean that is where the exposure occurred,” said Dr. Stonecipher. This epidemiological investigation must be completed for every case.

Boxes of mosquito specimens are shipped to the Arbovirus Laboratory by trained submitters. Careful packaging is important, because mosquitos must arrive alive. If mosquitos escape, opening the box can be a little too interesting. Contact the Arbovirus/Entomology Laboratory if you wish to submit mosquitos. The Laboratory will provide you with shipping boxes and supplies as well as submission guidelines and a training manual. For actual hands-on training, contact personnel in your local health service region.


Testing starts with identification of the mosquitos under the microscope. Different mosquito species prefer humans, animals or both and are therefore carriers of different viruses. Testing is then performed via cell culture isolation and Indirect Fluorescent Antibody Assay. Identified mosquitos are separated into pools for testing. The pools of mosquitos are homogenized in a bovine albumin diluent. The homogenized pools are inoculated into cell culture. The cell cultures are observed for 10 days for evidence of viral growth. If any cells exhibit viral growth, then the infected cells are tested by an indirect fluorescent antibody (IFA) test to identify the virus infecting the cells. If the IFA test detects West Nile virus or any other arbovirus that causes human disease, the laboratory notifies the submitter and the local health service region personnel.

Laboratorian identifying mosquitos under the microscope

To test human serum and CSF, the Laboratory uses a Microsphere-based immunologic assay (MIA) developed by the Centers for Disease Control and Prevention (CDC). The assay components are attached to microsphere – a microscopic spherical particle. Results are read using a modified flow cytometer in which dual lasers simultaneously identify the microsphere sets (bead sets) and measure fluorescence associated with the reaction. This measurement detects viral IgM antibodies.

Laboratorian doing serology testing for WNV

Testing using MIA technology takes only six hours. The MIA results are standardized and classified by using software that allows a single result to be determined. If the result is non-specific, further testing is done via IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA), which takes three days to identify IgM antibodies for WNV and Saint Louis Encephalitis (SLE). If the result is positive, the Laboratory tests for the presence of IgG antibodies. Specimens with only SLE positive MIA results are forwarded to the CDC for confirmation of flavivirus by neutralization.

Test results are returned to the submitter as quickly as possible so that they can be interpreted in relation to the patient’s clinical picture, other diagnostic findings, and epidemiological data.

Each West Nile case represents a sick individual or their family member who is often shocked by the “out of the blue” nature of the illness, Dr. Stonecipher said. They are confused by rumors and hear-say in their community, unsure how they could be sick when “there was nothing wrong with me before.” Some are not in any of the high-risk groups – those with pre-existing conditions, the old, and the young. “No matter how many times you’ve done this, it doesn’t really mean much to you until you’ve talked to someone on the phone,” said Dr. Stonecipher. People talk to her about the severity of the disease. “It’s scary because you don’t get better immediately. They’re upset. This is real life.”

Real life often isn’t pretty. Thus far, the West Nile Virus outbreak has resulted in 1,586 confirmed cases – 732 cases of West Nile Neuroinvasive Disease and 854 cases of West Nile Fever. There have been 71 deaths. Your best defense is laid out in “Four Ds”:

  1. Use insect repellent containing DEET, picaridin or oil of lemon eucalyptus.
  2. Dress in long sleeves and long pants when you are outside.
  3. Stay indoors at dusk and dawn, when mosquitoes are most active.
  4. Drain standing water where mosquitoes breed. Common breeding sites include old tires, flowerpots and clogged rain gutters.

by Jimi Ripley-Black 

 

 

Gen Probe Testing for Gonorrhea and Chlamydia

According to an old adage, “What you don’t know can’t hurt you.” As much as those of us who don’t like going to the doctor would like to argue, this is certainly not true in Public Health where diseases left undetected and untreated often lead to severe health problems. In the case of the sexually transmitted diseases (STD) Gonorrhea and Chlamydia – known as silent diseases – millions are affected in the United States yearly. However, people usually do not know they are infected because symptoms do not show immediately after exposure.

In the state of Texas, the Department of State Health Services (DSHS) HIV/STD Program identifies reports, prevents and controls infectious diseases, including HIV, AIDS and STDs like Gonorrhea and Chlamydia. The Laboratory Services Section is tasked with the critical screening and testing part of the program. The Women’s Health Laboratory (WHL) in San Antonio provided testing services for Gonorrhea and Chlamydia until the WHL officially closed on August 31, 2012. As a result, testing services for certain diseases have been moved to different laboratories. The Amplified GenProbe® testing for Gonorrhea/Chlamydia (GC/CT) was transferred to the DSHS Laboratory in Austin.

Nature of the Disease

Gonorrhea is a STD caused by the bacterium Neisseria gonorrhoeae. According to the Centers for Disease Control and Prevention (CDC), “Gonorrhea can grow easily in the warm, moist areas of the reproductive tract, including the cervix (opening to the womb), uterus (womb), and fallopian tubes (egg canals) in women, and in the urethra (urine canal) in women and men. The bacterium can also grow in the mouth, throat, eyes, and anus.”

Chlamydia, on the other hand, is caused by the bacterium Chlamydia trachomatis. CDC explains that “even though symptoms of chlamydia are usually mild or absent, serious complications that cause irreversible damage, including infertility, can occur "silently" before a woman ever recognizes a problem. Chlamydia also can cause discharge from the penis of an infected man.”

How common are Gonorrhea and Chlamydia?

The World Health Organization (WHO) reports an estimated annual global incidence of 62 million people with Gonorrhea while over 140 million are infected with Chlamydia. In the United States alone, over 1,300,000 chlamydial infection cases and 310,000 cases of gonorrhea were reported to CDC in 2010. In Texas, data shows approximately 122,439 Chlamydia cases and 30,493 Gonorrhea cases were reported to the DSHS Surveillance Program from January 1 to December 31, 2011.

Gonorrhea and Chlamydia can be transmitted during vaginal, anal or oral sex. Gonorrhea and Chlamydia can also be passed from an infected mother to her baby during vaginal childbirth.

Laboratory Testing

The Laboratory’s involvement in the disease detection process starts even before testing happens. First, submitters (doctor’s offices and local and regional health departments) collect specimens from patients to send to the laboratory. These specimens can be any of the following:  urine (male or female), female endocervical swabs, female vaginal swabs or male urethral swabs. These specimens are collected and sent via supplies obtained from the DSHS Laboratory. There are three collection test kits a submitter may order from the Laboratory:

  1. APTIMA ®  Urine Specimen Collection Kit for Male and Female Urine Specimens,
  2. APTIMA ®  Unisex Swab Specimen Collection Kit for Endocervical and Male Urethral Swab Specimens,  and
  3. APTIMA® Vaginal Swab Specimens kit.

These specimens are received by the Laboratory Specimen Acquisition Branch and accessioned for testing. In August 2012, the branch received more than 1,300 Gonorrheal/Chlamydia specimens; another 1,800 specimens were received in September. After accessioning, the specimens are transferred to the testing laboratory.

Photo of Gen Probe machine

Screening for Chlamydia and Gonorrhea is performed at the Microbiological Sciences Branch by the Serological Analysis Group. The group utilizes the Gen-Probe® Aptima® combo 2 assay (Gen Probe) to detect the presence of C trachomatis and N. gonorrhoeae. Gen Probe technology is able to measure both organisms at the same time, allowing faster turnaround time. In fact,

results are available within two to three days after specimen receipt. There are four possible results:  positive, negative, equivocal and invalid. In the event that results are either equivocal or invalid, the specimens are re-tested. When results are finalized, reports are sent back to submitters.

The DSHS Laboratory in Austin has tested approximately 3,000 specimens for GC/CT since it took over testing in August. Former customers of WHL are requested to contact the Laboratory for data related to testing performed by WHL, including previously released test results and reports.

by Jan Adversario

 

Laboratory Building Named for Former Legislator

Photo of group attending Lab Building Dedication

The Texas state laboratory was officially named the Dr. Bob Glaze Laboratory Services Section Building on September 7, 2012. The Laboratory’s lobby was packed with members of Dr. Glaze’s extended family and a select group of Laboratory managers and staff as DSHS Commissioner Dr. David L. Lakey introduced the event and highlighted the important testing work done in the building. Lillie Gilligan, a former co-worker, told stories of how Dr. Glaze helped make the building a reality. The ceremony concluded as family members unveiled a plaque, featuring a photo of Dr. Glaze, and a framed copy of the Texas State House Concurrent Resolution naming the building.

Dr. Glaze, known as “Dr. Bob” by colleagues and constituents, was a chiropractor, former legislator and member of the Texas Board of Health. He served 12 years in the Texas House of Representatives. During his time as a member of both the House Appropriations and Public Health committees, Dr. Glaze played a key role in securing funding for the Laboratory building.

“Dr. Glaze, from the time that he became a member of the Board of Health, was concerned about the safety of the employees working in the laboratory building and encouraged the department to start working on plans for the new building,” said Gilligan. He made sure that the Laboratory Director was involved in drawing up the plans, because they would know best what was needed and what safety issues must be addressed. “He kept after the commissioner to get this done,” said Gilligan. When the plans were ready, Dr. Glaze made sure the appropriation committee understood how important this was to the state of Texas and the safety of employees who worked in the building.

“Without his support and encouragement…this building would not have been built,” said Gilligan. “He was the guiding hand that kept it [going] no matter what got in the way. He was determined that Texas would have the best.” Gilligan said that recognizing Dr. Glaze for his work is an appropriate way to honor his memory. “He was Mr. Public Health when it came to what was then the Texas Department of Health and [is] now the Department of State Health Services.”

Dr. Glaze, who passed away in 2010 at the age of 82, is remembered as a tireless advocate for public health and improved health care who devoted himself to the wellbeing of Texas residents as a lawmaker and private citizen.

 

 

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THE LABORATORIAN
October 2012, Volume Four, Issue Two                          (Publication #E14-13156)
Published by DSHS Laboratory Services Section
PO Box 149347, MC 1947
Austin, TX 78714

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888 963 7111, ext 7318 Toll Free
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LABORATORY DIRECTOR
Grace Kubin, PhD
512 458 7318
email Grace

NEWSLETTER EDITOR
Jimi Ripley-Black
512 458 7318, ext 6505
email Jimi

Last updated October 18, 2012