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
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
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.
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 , 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
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
The first steps towards developing a vaccine against an insidious sexual transmitted infection (STI) have been accomplished by researchers at McMaster University.
Researchers at the Michael G. DeGroote Institute for Infectious Disease Research at McMaster have developed the first widely protective vaccine against chlamydia, a common STI that is mostly asymptomatic but impacts 113 million people around the world each year and can result in infertility.
In a study, recently published in the journal Vaccine, the researchers show that a novel chlamydial antigen known as BD584 is a potential vaccine candidate for the most common species of chlamydia known as Chlamydia trachomatis.
As most C. trachomatis infections are asymptomatic, chlamydia can often go untreated and lead to upper genital tract infections, pelvic inflammatory disease, and infertility. This is why the promise of a vaccine would be extremely beneficial, says David Bulir, co-author of the study.
Read at Science Daily
Great article by Aaron Carroll in the New York Times on the myths behind the rhinovirus.
I’ve become somewhat known for medical myth-busting (having been a co-author of three books on the subject), so a fairly large number of emails sent to me are from people with articles or studies that they think prove me wrong.
This week, as a few of us sniffle with summer colds, the emails are all about a new study that they think proves that cold weather makes you more likely to catch a cold.
I’m sorry to say that this continues to be a myth. Research doesn’t support it.
This latest study, published in the Proceedings of the National Academy of Sciences, is complicated research of cells in laboratory conditions. The researchers showed that cells kept at 37 degrees Celsius were more likely to undergoapoptosis (basically, cell suicide) than cells kept at 33 degrees Celsius. Apoptosis is a way that we protect ourselves from infection. If the infected cells kill themselves, then there’s fewer chances for replication of the viruses that infect them.
I’m sorry to say that this continues to be a myth. Research doesn’t support it.
Read at NYT
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
A new study reported that HHV-6A infects the lining of the uterus in 43% of women with unexplained infertility but cannot be found in the uterine lining of fertile women. Furthermore, the cytokine and the natural killer cell profiles were very different in patients with the infection. HHV-6A was found only in uterine endothelial cells, and not in the blood.
A team led by Roberta Rizzo, Roberto Marci, and Dario DiLuca of the University of Ferrara tested endometrial biopsies from 30 women with unexplained primary infertility as well as 36 fertile women. HHV-6 DNA was found in the endometrial samples from 13 of 30 infertile women (43%), but none of the fertile women. Surprisingly, all of the virus was HHV-6A, not HHV-6B, the virus that reactivates in immunocompromised patients and causes roseola in infants. Over 97% of HHV-6 reactivation in transplant patients is typed as HHV-6B.
Of interest, the investigators found a strong correlation between the level of estradiol and presence of an HHV-6A infection (p=0.02). They also found that the virus was active only during the secretory phase of the menstrual cycle, when estradiol levels were highest. Estradiol has also been shown to cause HSV1 reactivation (Miguel 2010), and steroids cause HHV-6 to reactivate disproportionately in patients with DIHS/DRESS (Ishida 2014).
Read at HHV-6 Foundation
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