Why Zika virus testing will take place in Richmond
RICHMOND, Va. — Testing for the Zika virus will soon take place at the Department of General Services Division of Consolidated Laboratory Services (DCLS) in Richmond. The Centers for Disease Control and Prevention designated the Richmond lab as a Zika virus testing laboratory. That will allow for more timely Zika virus test results.
“When facing threats to public health such as Zika virus, accurate and timely laboratory testing is not only important for providing appropriate patient care but also for supporting public health response efforts,” DCLS Director Dr. Denise Toney said.
DCLS’ serologic testing can detect antibodies in the blood of an infected person from approximately six days after symptoms are present up to 12 weeks after infection. The CDC would continue to run tests to confirm the presence of Zika.
The lab in Richmond is of several labs now doing this kind of work.
“Prior to DCLS being designated as a Zika virus testing laboratory, all patient specimens would be submitted to the CDC for testing,” a state spokesperson said. “The CDC quickly experienced a backlog of patient specimens arriving from all over the country. In order to expand the number of testing laboratories, the CDC acquired approval from the U.S. Food and Drug Administration (FDA) in late February under Emergency Use Authorization (EUA) to distribute a diagnostic test for detection of Zika virus to state public health laboratories nationwide that are part of the CDC’s Laboratory Response Network, an integrated network of laboratories that include Virginia’s DCLS.”
Richmond ranks high for Zika risk
Richmond is on the list of cities most at risk of Zika virus. A a recent poll revealed that Americans don’t know much about the Zika virus — a disease that many South American countries believe is a serious threat.
“It is not a surprise to me that Richmond is on the list,” said Danny Avula, Director, Richmond City Health District.
Richmond ranks 35 on a list of 50 high-risk U.S. cities, according to healthgrove.com.
CDC screens nearly 5,000 travelers for Zika, less than 200 test positive
The U.S. Centers for Disease Control and Prevention screened 4,534 people for the Zika virus between January and March, according to a report published Friday. All of those screened either traveled to or moved from areas where the mosquito-borne disease is circulating. Just over 4 percent tested positive for the virus.
More than 94 percent tested negative and another one person had an unspecified virus in the same family as Zika, such as dengue or yellow fever, or may have been vaccinated against a related virus.
The report, published by the CDC’s Morbidity and Mortality Weekly Report, sheds some light about the risk for travelers to the more than 40 countries and territories where the virus is circulating.
An estimated 40 million people travel between the continental United States and areas infected with the Zika virus, according to Health and Human Services Secretary Sylvia Burwell.
It’s not definitive, said Stephen Morse, professor of epidemiology at the Columbia University Mailman School of Public Health and director of the Infectious Disease Epidemiology Certificate Program. It does, however, offer a rough estimate for a returning traveler to know what the chances are of contracting the virus.
“The fact that the risk of contracting it is less than you might think … it might be somewhat reassuring,” he said.
Symptoms include rash, fever, joint pain and conjunctivitis, or red eyes, and are present in 20% of those infected with the virus. Of the pregnant women with no symptoms who were screened as recommended, 99% of them were negative for the virus.
While this indicates the risk may be lower than thought, the effects of the disease are still devastating. It can cause severe birth defects in babies born to mothers who had the virus while pregnant.
“It is reassuring that the proportion of asymptomatic pregnant women with confirmed Zika virus infection in this report was low. However, because of the potential serious adverse pregnancy and neonatal outcomes associated with maternal Zika virus infection, health care providers should continue to offer testing to pregnant women with potential exposure to Zika virus, even if they do not have symptoms,” the report said
The report has several limitations.
It does not account for where the travelers visited, how long they were in the affected area, or details of their potential exposure to the virus, such as if windows were screened or if they were using mosquito repellant. Only results from tests performed at the CDC are included, not those performed by state health departments. In addition, testing may have been delayed and therefore the individual screened may have forgotten that they experienced symptoms, an important consideration since those with symptoms were more likely to test positive than those who do not have any. The authors also caution that their findings do not apply to areas where there is active virus transmission.
Dr. Scott Lillibridge, an epidemiologist and professor at the Texas A&M Health Science Center School of Public Health, agreed with Morse that it’s reassuring that the numbers are not higher. However, “this isn’t anything to be taken lightly,” he said, adding that it signals the need to worry about travelers who do not have symptoms.