How Relevant Is Sexual Transmission of Zika Virus?

Plos: Sexual transmission of Zika virus could be as important as transmission through bites from infected mosquitoes, if media attention is any indicator [1,2]. One article argues that “sexual transmission is likely to be a significant contributor to the Zika virus’s spread” [3]. The level of attention in news media is high in the United States and Europe, where most Zika virus infections have been detected in travellers returning from endemic areas. Epidemiologists have inferred transmission through sexual intercourse when sexual partners who have not travelled develop symptoms and are found to have Zika virus in blood samples. Each case of potential sexual transmission receives intense scrutiny, including enquiry into sexual partnership details and travel histories and tests to detect Zika virus in blood, urine, and semen or vaginal secretions. By 9 September 2016, 12 countries had reported cases of non–mosquito-borne Zika virus transmission to the World Health Organization [4], including cases of male-to-female, female-to-male, and male-to-male transmission [5].

Zika Virus Can Cause Severe Damage to Retina in Infants

JAMA: In a study published online by JAMA Ophthalmology, Rubens Belfort Jr., M.D., Ph.D., of the Federal University of Sao Paulo, Brazil, and colleagues examined the affected retinal layers in infants with congenital Zika syndrome and associated retinal abnormalities using optical coherence tomography (OCT). The study included 8 infants (age range, 3-5.1 months) with congenital Zika syndrome (CZS), the term created for a variety of anomalies associated with intrauterine Zika virus infection. Optical coherence tomographic images (a noninvasive diagnostic imaging tool that provides cross-sectional retinal images) were obtained in the affected eyes of 7 infants with CZS who had undergone previous ophthalmologic examinations on March 17, 2016, and in 1 infant on January 1, 2016. An IgM antibody-capture enzyme-linked immunosorbent assay for Zika virus was performed on the cerebrospinal fluid samples of 7 of the 8 infants, and other congenital infections were ruled out.

Hopes raised that Zika virus could be treated in the womb

NHS: "Scientists say they may have found a way to protect babies in the womb from the harmful effects of Zika," BBC News reports. Researchers have had success using antibody therapy to treat mice when they were still in their mothers' womb. There is evidence that Zika virus, which has become widespread in South America recently, can damage the development of babies in the womb. One of the most striking birth defects associated with Zika is babies being born with abnormally small heads and brains (microcephaly).

Could Zika Virus Have Lasting Impact on Male Fertility?

NIH: Recent research has shown that the mosquito-borne Zika virus has the potential to cause serious health problems, including severe birth defects in humans. But the damaging effects of Zika might not end there: results of a new mouse study show that the virus may also have an unexpected negative—and possibly long-lasting—impact on male fertility. In work published in the journal Nature, an NIH-funded research team found that Zika infections can persist for many weeks in the reproductive systems of male mice [1].

Immune system may give protection from Zika a booster shot

Scimex: A new antibody therapy may prevent fetal damage in pregnant mice infected with the Zika virus, a Nature paper suggests. Owing to differences in gestational features between mice and humans, further studies are needed to determine whether the findings can be translated to the clinic, but it is hoped that the discovery will help to inform vaccine design efforts.

Antibody protects developing fetus from Zika virus, mouse study shows

Saint Louis: The most devastating consequence of Zika virus infection is the development of microcephaly, or an abnormally small head, in fetuses infected in utero. Now, researchers at Washington University School of Medicine in St. Louis and Vanderbilt University School of Medicine have identified a human antibody that prevents — in pregnant mice — the fetus from becoming infected with Zika and damage to the placenta. The antibody also protects adult mice from Zika disease.

Testing of investigational inactivated Zika vaccine in humans begins

NIH: First of five planned clinical trials to test ZPIV vaccine. The first of five early stage clinical trials to test the safety and ability of an investigational Zika vaccine candidate called the Zika Purified Inactivated Virus (ZPIV) vaccine to generate an immune system response has begun at the Walter Reed Army Institute of Research (WRAIR) Clinical Trial Center in Silver Spring, Maryland. Scientists with WRAIR, part of the U.S. Department of Defense (DoD), developed the vaccine. The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), is co-funding the Phase 1 clinical trial with WRAIR, serving as the regulatory sponsor and providing other support.