Written by Tim Newman

Epstein-Barr virus is one of the most common viruses to infect humans, and it also appears to play a role in breast cancer. The findings of a recent study may have uncovered the mechanism behind this relationship.

EBV's influence on breast cancer development may soon be understood.

Epstein-Barr virus (EBV), a member of the herpes virus family, is easily transmitted through oral transfer of saliva and by genital secretions.

An incredible 90 percent of all humans on earth are thought to be infected by EBV.

Most sexually active adults will pick up the virus at some point in their lives, and about half of all 5-year-olds have evidence of previous infection.

Although the majority of carriers do not display any symptoms of infection, it can lead to complications in some individuals, most commonly, infectious mononucleosis, also known as glandular fever.

EBV infects two major cell types, firstly, components of the immune system, known as B cells; secondly, epithelial cells, which line cavities of the body, blood vessels, and organs.

Over the years, EBV has also been associated with a number of specific cancer types such as African Burkitt lymphoma (a cancer of the lymphatics), Hodgkin's disease (a blood cancer), nasopharyngeal carcinoma (a rare head and neck cancer), gastric adenocarcinoma (a type of stomach cancer), and leiomyosarcoma (a smooth muscle tumor).

An estimated 200,000 malignancies are caused by EBV annually.

EBV and breast cancer

Along with the cancers named above, a number of studies have glimpsed a relationship between EBV and breast cancer. Studies carried out in India, North Africa, China, and southern Europe have all noted a relationship.

Although EBV's relationship with cancer generation has been demonstrated, it has proven tough to pin down the processes behind it. Often, the breast cancer will not appear for many years after the initial viral infection, making a causal role difficult to establish.

A team from the Hematology/Oncology Division at Beth Israel Deaconess Medical Center (BIDMC) in Massachusetts, led by Dr. Gerburg Wulf, joined forces with Harvard Medical School in Boston to investigate this puzzle in more detail. The findings are published this week in the journal EBioMedicine.

The researchers cultured breast cells in the presence of EBV; specifically, they used cells known as primary mammary epithelial cells (MECs).

The team found that EBV binds to a specific receptor on normal breast cells called CD21, which leads to infection. The viral infection caused the breast cells to behave like stem cells - they were able to keep on dividing.

Studying EBV and its impacts

Dr. Wulf and his team implanted MECs into mice; they noted that the EBV infection assisted some cancer types, enabling certain proteins to speed up the formation of breast cancer. When the genes of the MECs infected by EBV were examined, they saw genetic characteristics normally associated with a particularly aggressive breast cancer - high-grade, estrogen-receptor-negative breast cancer.

As the authors wrote, "EBV infection of MECs lowers the threshold for malignant transformation." So, although EBV is not a causal factor in itself, it increases the likelihood of developing cancer later in life.

Although the results will need to be replicated and other aspects of the pathway examined, the findings add to our understanding of the causes and influences of breast cancer.

"We think that if a young woman develops EBV during her teenage years or later, her breast epithelial cells will be exposed to the virus and can be infected.

While for most individuals, there will be no long-term consequences, in some, the infection may leave genetic scars and change the metabolism of these cells.

While these are subtle changes, they may, decades later, facilitate breast cancer formation."

Gerburg Wulf, MD, PhD

EBV, it seems, may contribute to breast cancer development by predisposing MECs to become malignant further down the road. However, once cancerous, EBV no longer worsens the disease. The authors point out that the findings add weight to the argument for childhood EBV vaccination. They may also influence the way in which screening is carried out in the future.

Vaccination against a single strain of Zika virus should be sufficient to protect against genetically diverse strains of the virus, according to a new study.

Read the full story here.

Researchers have studied the relationship between health insurance coverage and tobacco and alcohol use among reproductive age women in the US, and whether there were differences according to pregnancy status. The findings showed that pregnant women with insurance coverage had lower odds of alcohol use in the past month; however the odds of tobacco use were not affected. For non-pregnant women, insurance coverage resulted in higher odds of alcohol use but lower odds of using tobacco.

Read the full story here.

Columbia University's Mailman School of Public Health. (2016, July 26). Health insurance coverage is associated with lower odds of alcohol use by pregnant women. ScienceDaily. Retrieved August 2, 2016 from www.sciencedaily.com/releases/2016/07/160726131700.htm

CDC periodically revises its contraceptive guidance for health care providers after review of the scientific evidence and consultation with national experts. These recommendations are intended to assist health care providers when they counsel women, men, and couples about contraceptive method choice and provide evidence-based guidance to reduce medical barriers to contraception access and use.

U.S. Medical Eligibility Criteria for Contraceptive Use, 2016 (U.S. MEC)  

The U.S. MEC includes evidence-based recommendations for using specific contraceptive methods by women and men who have certain characteristics or medical conditions. The 2016 U.S. MEC updates the previous 2010 U.S. MEC with new guidance including: New recommendations for women with cystic fibrosis, women with multiple sclerosis, and women using certain psychotropic drugs or St. John’s wort. Revisions to the recommendations for emergency contraception, including the addition of ulipristal acetate. Revisions to the recommendations for postpartum women; women who are breastfeeding; women with known dyslipidemias, migraine headaches, superficial venous disease, gestational trophoblastic disease, sexually transmitted diseases (STDs), and human immunodeficiency virus (HIV); and women using antiretroviral therapy.

U.S. Selected Practice Recommendations for Contraceptive Use, 2016 (U.S. SPR)

The U.S. SPR provides evidence-based recommendations for common, but sometimes complex, questions regarding initiation and use of specific contraceptive methods. The 2016 U.S. SPR updates the previous 2013 U.S. SPR with new guidance including: New recommendations for the use of medications to ease insertion of intrauterine devices and Revised recommendations for starting regular contraception after the use of emergency contraceptive pills. Updated guidance documents, provider tools, and other electronic resources are available: U.S. Medical Eligibility Criteria for Contraceptive Use, 2016 U.S. Selected Practice Recommendations for Contraceptive Use, 2016

Increase in rate of HCV detection in women of childbearing age, HCV testing among infants

TUESDAY, July 26, 2016 (HealthDay News) -- From 2011 to 2014 there were increases in the rate of hepatitis C virus (HCV) detection among women of childbearing age, according to research published in the July 25 early-release issue of the U.S. Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report. Alaya Koneru, M.P.H., from the CDC in Atlanta, and colleagues examined trends in HCV detection among women of childbearing age, HCV testing among infants (aged ≤2 years), and the proportion of infants born to HCV-infected women nationally and in Kentucky. The researchers found that among women of childbearing age, national rates of HCV detection increased 22 percent during 2011 to 2014. Among children aged ≤2 years, HCV testing increased 14 percent. Based on data from birth certificates there was a 68 percent increase in the proportion of infants born to HCV-infected mothers (from 0.19 to 0.32 percent). In Kentucky, which had the highest incidence of acute HCV infection during 2011 to 2014, there was a more than 200 percent increase in the HCV detection rate among women of childbearing age; a 151 percent increase in HCV testing among infants; and a 124 percent increase in the proportion of infants born to HCV-infected women (0.71 to 1.59 percent). "These findings highlight the importance of following current CDC recommendations to identify, counsel, and test persons at risk for HCV infection, including pregnant women, as well as consider developing public health policies for routine HCV testing of pregnant women," the authors write. Full Text

Copyright © 2016 HealthDay. All rights reserved.

Dutch case finds woman's infection in South America may have spurred her pregnancy loss

En Español

WEDNESDAY, July 27, 2016 (HealthDay News) -- Dutch researchers are reporting a case of miscarriage tied to maternal infection with the mosquito-borne Zika virus.

The virus is best known for its links to a devastating fetal birth defect known as microcephaly, where babies are born with smaller-than-expected heads and brains. But Zika's links to miscarriage haven't been clear.

"Data linking Zika virus infection to fetal death have been reported in only a handful of cases," wrote a team led by Dr. Annemiek van der Eijk, of Erasmus Medical Center in Rotterdam, the Netherlands.

The researchers said a 31-year-old Dutch woman lost her baby at 11 weeks' gestation, after contracting Zika on a trip to the South American country of Suriname. Suriname borders Brazil, which has been hit hard by thousands of cases of Zika-linked microcephaly.

The report was published online July 27 in the New England Journal of Medicine. In it, the researchers described how the pregnant woman became ill with headache, joint pain and rash the day after she returned to the Netherlands after more than three weeks in Suriname.

She recovered after six days. But, about two weeks after her symptoms first emerged, doctors found no fetal heartbeat -- indicating a miscarriage -- when the woman went in for a routine ultrasound. She received a D&C (dilation and curettage) a week later.

Traces of Zika virus were found in amniotic fluid, placental tissue, and in the mother's urine and blood, van der Eijk's team noted. The virus was also found in fetal stem cells, suggesting that Zika "replicates in [these cells] involved in early stage embryo development," the researchers explained.

The study can't prove that maternal Zika infection caused the miscarriage, only that there was an association. However, the Dutch team pointed out that traces of Zika virus in blood and fetal tissue were found for at least 21 days, suggesting that the "window" for testing a pregnant woman for the virus may need to be expanded. The current testing window set by the U.S. Centers for Disease Control and Prevention is 14 days.

In the United States, the CDC has been keeping a close eye on Zika, and revising its recommendation for pregnant women accordingly.

On Monday, the CDC updated its guidelines to say that pregnant women could contract Zika from a sex partner of either gender. While mosquitoes remain the biggest source of infection, cases of sexually transmitted Zika do occur.

Based on that, the CDC now "recommends that all pregnant women with sex partners (male or female), who live in or traveled to an area with Zika, use condoms during sex or abstain from sex for the remainder of their pregnancy," the agency said.

"Sex includes vaginal, anal and oral sex, and may also include the sharing of sex toys," the CDC said.

Any pregnant woman who suspects that she may have been exposed to Zika -- either through a mosquito bite or sexual contact with an infected person -- should be tested for the virus, the agency stressed.

The CDC also pointed out that "new information has indicated that some infected pregnant women can have evidence of Zika virus in their blood for longer than the previously recommended seven-day window."

Because of that new data, the agency updated its recommendation to lengthen the time frame for blood testing for Zika to 14 days.

The vast majority of cases of Zika-linked illness and birth defects are occurring in Latin America. However, Zika may be making inroads into the United States. Late last week, Florida health officials said they were investigating a second possible case of locally transmitted Zika infection.

The first possible case of local infection in the continental United States was reported early last week by the Florida health department. That case involved a woman in Miami-Dade County, while the newer, second case involved a resident of Broward County, north of Miami.

Florida health officials said they were capturing and testing mosquitoes in the neighborhoods where the two unidentified patients live. Meanwhile, Gov. Rick Scott has asked for assistance from the CDC, The Miami Herald reported.

The CDC said it has provided $2 million for Zika preparedness and another $5.6 million was just allotted, the newspaper reported.

There have been more than 1,400 confirmed Zika cases in the United States, but so far all of them have been contracted through travel abroad -- either by a mosquito bite or by sexual intercourse with someone who had traveled to a Zika-infected area.

CDC officials have said repeatedly they expect to see cases of local transmission of the Zika virus this summer in southern states with warm, humid climates such as Florida, Louisiana and Texas. The virus is typically transmitted through the bite of Aedesmosquitoes.

The CDC has also reported 14 cases of sexually transmitted infections. These infections are thought to have occurred because the patients' partners had traveled to countries where Zika is circulating, the CDC said.

Typically, the Zika virus doesn't cause serious illness. Only about 20 percent of patients notice symptoms.

But the virus also has been linked to a rare paralyzing condition called Guillain-Barre syndrome.

The CDC advises pregnant women not to travel to an area where Zika transmission is ongoing, and to use insect repellent and wear long pants and long-sleeved shirts if they are in those areas.

More information

The U.S. Centers for Disease Control and Prevention provides more information onmosquito-borne diseases.

This Q&A will tell you what you need to know about Zika.

To see the CDC list of sites where Zika virus is active and may pose a threat to pregnant women, click here.

SOURCES: July 27, 2016, New England Journal of Medicine, online; July 25, 2016, news release, U.S. Centers for Disease Control and Prevention; July 19, 2016, news release, Florida Department of Health; July 18, 2016, media briefing with Satish Pillai, M.D., incident manager, U.S. Centers for Disease Control and Prevention Zika Response; July 18, 2016, news release, U.S. Centers for Disease Control and Prevention; Miami Herald

-- HealthDay staff

Last Updated: Jul 27, 2016

Copyright © 2016 HealthDay. All rights reserved.

Pink Book Webinar Series
This online series of 15 webinars provides an overview of the principles of vaccination, general recommendations, immunization strategies for providers, and specific information about vaccine-preventable diseases and the vaccines that prevent them.

The 2016 U.S. Medical Eligibility Criteria for Contraceptive Use (U.S. MEC) comprises recommendations for the use of specific contraceptive methods by women and men who have certain characteristics or medical conditions.

Curtis KM, Tepper NK, Jatlaoui TC, et al. U.S. Medical Eligibility Criteria for Contraceptive Use, 2016. MMWR Recomm Rep 2016;65(No. RR-3):1–104. DOI: http://dx.doi.org/10.15585/mmwr.rr6503a1.

CDC has updated interim guidance for the prevention of sexual transmission of Zika virus. The recommendations apply to all men and women who have traveled to or reside in areas with active Zika virus transmission and their sex partners.

Update: Interim Guidance for Prevention of Sexual Transmission of Zika Virus — United States, July 2016

U.S. Zika Pregnancy Registry
To understand more about Zika virus infection, CDC established the U.S. Zika Pregnancy Registry and is collaborating with state, tribal, local, and territorial health departments to collect information about pregnancy and infant outcomes following laboratory evidence of Zika virus infection during pregnancy