Another DNA Vaccine for Zika Shows Promise

A preventive DNA vaccine encoding two Zika structural proteins protected Rhesus macaques from viral infection. The results, published today (September 22) in Science, are encouraging for organizers of the ongoing Phase 1 clinical trial testing one of the two vaccines examined in this nonhuman primate study. The new work suggests a minimal antibody level in the blood that is likely necessary for protection against Zika virus infection in in people.

Read at The Scientist

Zika-Associated Brain Injuries Found in Monkey Fetus

After scientists infected a pregnant pigtail macaque with Zika virus, the primate’s fetus developed brain lesions similar to those observed in some human babies born to Zika-infected mothers, the team reported yesterday (September 12) in Nature Medicine.

“Our results remove any lingering doubt that the Zika virus is incredibly dangerous to the developing fetus and provides details as to how the brain injury develops,” study coauthor Kristina Adams Waldorf of the University of Washington School of Medicine said in a statement.

 

Read at The Scientist

Zika Virus’s Spread Pushes Testing Labs to Expand Capacity

Study found a gap between resources, potential need in the case of a U.S. outbreak

 

As summer drew near, the nation’s health officials took stock of whether they could handle a surge in demand for Zika diagnostic tests if disease-carrying mosquitoes began to proliferate.

A survey of state and local laboratories found enough capacity to perform 3,500 to 5,000 tests a week for the Zika virus. But that wouldn’t be enough to meet demand under the Centers for Disease Control and Prevention’s worst-case scenario for a domestic Zika outbreak.

The gap was “considerable,” said Kelly Wroblewski, director of infectious diseases for the Association of Public Health Laboratories, which conducted the April survey.

The finding set off a rush to expand lab capacity that continues as Zika’s foothold in the U.S. expands. In recent months, dozens of public health laboratories—which work with the government to monitor public health and screen for disease—bought equipment, stockpiled supplies and trained employees needed to start Zika testing, said state and local health officials.

Twelve California public health labs are preparing to start performing Zika tests; five others already do. The health department in Houston conducts one type of Zika test and will perform a second “as soon as we can get the equipment in the door,” said Larry Seigler, director of the city’s health labs.

 

Read at Wall Street Journal

Zika found to remain in sperm for record six months

INFECTION DYNAMICS IN A TRAVELLER WITH PERSISTENT SHEDDING OF ZIKA VIRUS RNA IN SEMEN FOR SIX MONTHS AFTER RETURNING FROM HAITI TO ITALY, JANUARY 2016

 

A patient, who developed fever and rash after returning from Haiti to Italy, was diagnosed with Zika virus (ZIKV) infection in January 2016. Longitudinal follow-up laboratory testing was performed to characterise ZIKV RNA and antibody dynamics during acute infection. A relevant finding in this case was the persistent shedding of ZIKV RNA in semen for six months after symptom onset.

Case report

In January 2016, a man in his early 40s returning to Italy from a two-week stay in Haiti developed fever (38.5 °C) and pruritic maculopapular rash on his trunk and arms that fully resolved after three days. The patient, who reported mosquito bites in Haiti, had an unremarkable past personal medical history. Laboratory analyses, performed at day 3 after symptom onset, showed blood cell count and liver function tests within the normal range. Testing for dengue, chikungunya and ZIKV infection, according to previously described methods [1], demonstrated the presence of ZIKV RNA in plasma and urine at 175 copies/mL and 25,600 copies/mL, respectively, and ZIKV-specific IgM but not IgG antibodies. Dengue virus (DENV) IgG antibodies were also detected by ELISA, but they represented cross-reacting antibodies induced by previous vaccination against yellow fever virus, as confirmed by virus neutralisation assays; DENV IgM, DENV NS1 antigen and chikungunya virus IgM and IgG were negative. Sequencing of the full ZIKV genome was obtained directly from a urine sample collected at diagnosis (GenBank KX269878), which demonstrated over 99.6% nucleotide sequence identity with ZIKV strains circulating in Haiti (GenBank KU509998 and KX051563).

Read at EuroSurveillance

Blood Banks Step Up Efforts Against Zika Contamination

CDC says virus poses a low risk to blood supply in U.S., but experts say precautions needed

 

As concerns rise about the spread of Zika in the U.S., regulators and blood banks are moving to protect the safety of the blood supply.

To guard against accidental transmission of the mosquito-borne virus through blood transfusions, the Food and Drug Administration on July 27 told banks in Florida’s Miami-Dade and Broward counties—where officials are investigating the first cases in the continental U.S. of local transmission of the virus—to stop collecting blood until they can screen each donation for Zika.

Some blood banks could start checking blood samples immediately, because the FDA allowed them to use one of two new lab tests for Zika even before they have been officially approved.

OneBlood, which collects 3,000 blood donations daily in Florida, George, Alabama and South Carolina, said it started screening for Zika late last week. “Everything we draw we check for Zika now,” said Rita Reik, chief medical officer.

She said she couldn’t disclose whether any sample had tested positive, but if one did the blood bank would notify both the donor and the Florida Health Department. So far, she said, “The results have been quite reassuring.”

 

Read at Wall Street Journal

 

First Suspected Female-to-Male Sexual Transmission of Zika Virus — New York City, 2016

The CDC reports that there has been the first suspected case of female-to-male transmission of the Zika virus.

A routine investigation by the New York City (NYC) Department of Health and Mental Hygiene (DOHMH) identified a nonpregnant woman in her twenties who reported she had engaged in a single event of condomless vaginal intercourse with a male partner the day she returned to NYC (day 0) from travel to an area with ongoing Zika virus transmission. She had headache and abdominal cramping while in the airport awaiting return to NYC. The following day (day 1) she developed fever, fatigue, a maculopapular rash, myalgia, arthralgia, back pain, swelling of the extremities, and numbness and tingling in her hands and feet. In addition, on day 1, the woman began menses that she described as heavier than usual. On day 3 she visited her primary care provider who obtained blood and urine specimens. Zika virus RNA was detected in both serum and urine by real-time reverse transcription–polymerase chain reaction (rRT-PCR) performed at the DOHMH Public Health Laboratory using a test based on an assay developed at CDC (1). The results of serum testing for anti-Zika virus immunoglobulin M (IgM) antibody performed by the New York State Department of Health Wadsworth Center laboratory was negative using the CDC Zika IgM antibody capture enzyme-linked immunosorbent assay (Zika MAC-ELISA) (2)

Read at CDC 

Peril on Wings: 6 of America’s Most Dangerous Mosquitoes

With the spread of the Zika virus, the threat posed by the tiny mosquito has been magnified into shark-size proportions.

But among the more than 3,000 species of the insect worldwide, only two in the Americas are known carriers of the virus: the yellow fever mosquito (Aedes aegypti) and the Asian tiger mosquito (Aedes albopictus).

The potential range of the two species in the United States helps explain where Zika could be a threat. The yellow fever mosquito, for instance, prefers the hot and humid climate in Florida and the southeastern part of the country. But it has colonized states as far west as California and Hawaii, and has the potential to live as far north as Connecticut in warmer weather, according to the Centers for Disease Control and Prevention. The Asian tiger mosquito, meanwhile, also favors tropical and subtropical locales but can withstand cooler temperatures, so it can range farther. In summertime, the insect can sometimes even be found in northern states like Maine and Minnesota.

Read at New York Times

The List of Zika Birth Defects is Even Longer Than We Thought

Even without microcephaly, seizures and developmental delays may appear in the months following birth

 

The full scope of Zika-related birth defects may extend far beyond abnormally small heads and brain damage. Research to be presented next week at a teratology conference in San Antonio, Texas, suggests that serious joint problems, seizures, vision impairment, trouble feeding and persistent crying can be added to the list of risks from Zika exposure in the womb.

The new findings confirm doctors’ concerns that even when Zika-exposed babies are born without microcephaly and appear largely normal at birth they can go on to have health issues including seizures and developmental delays that only become apparent in the weeks and months after birth. The new work also reinforces recent findings that suggest the type of outcomes the babies experience also varies by what trimester their mothers were in when they were exposed to Zika—with few cases of microcephaly when mothers were exposed during the third trimester.

 

Read at Scientific American

Mosquitoes carrying Zika virus could hit U.S. in the next month

WASHINGTON–Mosquitoes carrying the dangerous Zika virus are expected to begin infecting Americans within the U.S. in the next “month or so,” the government’s top infectious disease expert said Sunday, as officials race to prevent a widespread outbreak of the virus that is believed linked to birth defects.

Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said on ABC’s This Week that more than 500 Americans already have the Zika virus. But he said all those cases are travel-related, meaning the individuals were either infected while outside the U.S. or contracted it from someone who traveled.

Read at Market Watch

Bacterium Blocks Zika’s Spread

Infecting mosquitoes with Wolbachia greatly reduces the insects’ abilities to transmit the virus.

A bacterium known to prevent the spread of dengue and other viruses has now been shown to block transmission of Zika. Aedes aegypti mosquitoes carrying Wolbachia bacteria were highly resistant to Zika virus infection, and were unable to transmit the virus via their saliva, researchers in Brazil reported in a study published today (May 4) in Cell Host & Microbe. The findings highlight a possible mechanism for fighting the current primary viral vector in the ongoing Zika outbreak.

“It’s an exciting and encouraging study,” said Stephen Dobson, an entomologist at the University of Kentucky who studies A. aegypti biology but was not involved with the work. “To my knowledge, this is first study showing interference of Wolbachia and Zika transmission,” Dobson told The Scientist.

 

Read at The Scientist