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Experimental herpes vaccine shows promise in lab trials

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Scientists are reporting early success with an experimental herpes vaccine that uses a genetically modified version of the virus.

The gene edit prevents the virus from performing its normal evasive maneuver: hiding out in nervous system cells in order to elude the immune system.

So far, the vaccine has only been tested in lab animals. But scientists hope the genetic tweak will eventually allow the vaccine to succeed where past ones have failed.

The target is herpes simplex virus, or HSV, which in humans includes HSV-1 and HSV-2. Both can cause genital herpes, though HSV-1 is best known for triggering cold sores.

Globally, a half-billion people aged 15 to 49 have a genital herpes infection, according to the World Health Organization.

Those figures alone show there is a “huge need” for a vaccine, said Gary Pickard, one of the researchers on the new study.

But beyond that, once HSV invades the body, it’s there to stay, said Pickard, a professor of neuroscience at the University of Nebraska-Lincoln School of Veterinary Medicine and Biomedical Sciences.

To evade the immune system, the virus works its way into nerve cells and remains there in a dormant state. It can periodically become active again, traveling to the skin and causing sores and other symptoms.

In addition to those flare-ups, HSV infection can sometimes lead to complications. Pregnant women can, rarely, pass it to their newborns, who can become very sick or die, said Terri Warren, a registered nurse and medical advisor to the American Sexual Health Association.

Genital sores, and active HSV infection, also leave people more vulnerable to contracting HIV.

“In some places,” Warren said, “it accounts for many cases of HIV.”

Genital herpes also exacts a psychological toll, she explained, because it’s a lifelong infection that people can transmit to their partners, even when they are symptom-free.

That’s why researchers have been trying for years to create a preventive vaccine — with no success thus far.

As Pickard explained, one issue is that some candidate vaccines use only a subset of HSV components, or antigens, to try to generate an immune response. And that may not be enough: One vaccine with that design failed to prevent HSV-2 infection in a clinical trial involving thousands of young women.

Some other experimental vaccines have used a live, weakened form of HSV, but have run into similar issues.

“They’ve essentially made the virus so ‘sick’ that it can’t illicit a strong immune response,” Pickard said.

The new approach, recently described in the journal npj Vaccines, might circumvent those problems.

For the study, the researchers tested a vaccine made with a live, weakened form of HSV-1 that has a key genetic edit: It prevents the virus from advancing into the nervous system, while allowing it to replicate outside nerve tissue, to draw an immune response.

In lab experiments with guinea pigs, the tactic showed promise.

Of 12 animals given skin injections of the vaccine, only one developed sores after being exposed to HSV-2. In contrast, sores cropped up in 10 of 12 guinea pigs given no vaccine, and in five of 12 given the vaccine that failed in the earlier, human clinical trial.

In addition, the modified vaccine cut the viral shedding period by more than half, from 29 days to about 13. That’s important, Pickard said, because in humans it’s the viral shedding that can transmit the infection, even when there are no sores present.

“The findings on viral shedding are positive,” agreed Warren, who was not involved in the research.

She said a big question is whether a version of the vaccine that uses HSV-2 — rather than HSV-1 — can be shown effective in animals.

The researchers are working on that. Pickard said they are encouraged by the fact that the current vaccine showed “cross-protection” against HSV-2: If anything, they anticipate that an HSV-2 version will be more effective.

The road to an approved vaccine, however, is a long and very expensive one.

The hope is to have a vaccine ready for initial, phase I human testing within a few years, according to Pickard.

More information

The American Sexual Health Association has more on herpes.

Copyright 2020 HealthDay. All rights reserved.



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‘Green prescriptions’ could cancel mental health benefits for some

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So-called “green prescriptions” may end up being counterproductive for people with mental health conditions, researchers say.

Spending time in nature is believed to benefit mental health, so some doctors are beginning to “prescribe” outdoor time for their patients.

That led researchers to investigate whether being in nature helps actually does help people with issues such as anxiety and depression. They collected data from more than 18,000 people in 18 countries.

The takeaway: Time in nature does provide several benefits for people with mental health conditions, but only if they choose on their own to visit green spaces.

While being advised to spend time outdoors can encourage such activity, it can also undermine the potential emotional benefits, according to the authors of the study published this month in the journal Scientific Reports.

The researchers said they were surprised to find that people with depression were spending time in nature as often as folks with no mental health issues, and that people with anxiety were doing so much more often.

While in nature, those with depression and anxiety tended to feel happy and reported low anxiety. But those benefits appeared to be undermined when the visits were done at others’ urging, the investigators found.

The more external pressure people with depression and anxiety felt to visit nature, the less motivated they were to do so and the more anxious they felt.

“These findings are consistent with wider research that suggests that urban natural environments provide spaces for people to relax and recover from stress,” said study leader Michelle Tester-Jones, a postdoctoral research associate at the University of Exeter in the United Kingdom.

But the findings also show that health care practitioners and loved ones should be sensitive about recommending time in nature for people who have mental health issues.

“It could be helpful to encourage them to spend more time in places that people already enjoy visiting, so they feel comfortable and can make the most of the experience,” Tester-Jones said in a university news release.

More information

For more on the benefits of green spaces, go to the National Recreation and Park Association.

Copyright 2020 HealthDay. All rights reserved.



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Study: Nearly half of ‘essential workers’ in U.S. at risk for severe COVID-19

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Nov. 9 (UPI) — Nearly half of those classified as “essential workers” in the United States are at increased risk for severe COVID-19, according to an analysis published Monday by JAMA Internal Medicine.

This means that more than 74 million workers and those with whom they live could be at risk for serious illness, based on disease risk guidelines developed by the U.S. Centers for Disease Control and Prevention, the researchers said.

“Many parts of the country face high and rising infection rates, [and] we should not think about work exposure and health risks in isolation, given that workers and persons at increased risk often live in the same households,” study co-author Thomas M. Selden told UPI.

“Insofar as we can reduce the prevalence of COVID-19 in our communities, we can reduce the extent to which policymakers have to choose between the economy and keeping the population safe,” said Selden, an economist with the U.S. Department of Health and Human Services’ Agency for Healthcare Research and Quality.

Since the COVID-19 pandemic spread to the United States in March, states and cities across the country have instituted lockdown measures designed to limit the spread of the disease.

Many of these measures entailed closing schools and non-essential businesses, with only banks, grocery stores, pharmacies and other businesses deemed to provide vital services allowed to stay open.

For this study, Selden and his colleagues analyzed data on the U.S. workforce to examine how many people were in essential jobs, how often they were able to work at home, their risk for severe COVID-19 and the potential health risks for their household members.

Of the more than 157 million workers across the country, 72% are in jobs deemed essential — based on U.S. Department of Homeland Security criteria — and more than three-fourths of all essential workers are unable to work at home, Selden said.

Essential workers include those in the medical and healthcare, telecommunications, information technology systems, defense, food and agriculture, transportation and logistics and energy, water and wastewater industries, as well as those in law enforcement and public works, the DHS criteria stipulates.

The study notes that up to 60% of these workers have underlying health issues, placing them at increased risk for severe COVID-19 if they get infected, as defined by U.S. Centers for Disease Control and Prevention guidelines.

Those with diabetes, heart disease, high blood pressure and chronic respiratory conditions like asthma are considered to be at high risk for serious illness, the CDC says.

Based on these findings, between roughly 57 million and 74 million adults working in on-site essential jobs — and their families — are at increased risk for serious illness, Selden and his colleagues estimated.

“Policymakers face important decisions about how to balance the economic benefits of keeping workers employed and the public health benefits of protecting those with increased risk of severe COVID-19,” Selden said.

“These issues arise in the context of decisions to close segments of the economy and decisions about how to distribute vaccines, which will initially be available only with limited supply, [and] become all the more difficult when the prevalence of infection rises in parts of the country,” he said.



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Study: Hydroxychloroquine no better than placebo for hospitalized COVID-19 patients

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Nov. 9 (UPI) — COVID-19 patients treated with hydroxychloroquine showed no signs of significant improvement in “clinical status” compared with those given a placebo, a study published Monday by JAMA found.

Patients given a five-day course of the drug were scored as “category six” based on the World Health Organization’s seven-category COVID Ordinal Outcomes Scale, the same as those given a placebo, the researchers said.

Also, 28 days after they started treatment, 10.4% of those treated with hydroxychloroquine died, just slightly lower than the 10.6% fatality rate in the placebo group.

“The results show that hydroxychloroquine did not help patients recover from COVID-19,” study co-author Dr. Wesley H. Self told UPI.

“In the study, patients treated with hydroxychloroquine and those treated with a placebo had nearly identical outcomes, [so] I do not foresee any role for hydroxychloroquine in acutely ill patients hospitalized with COVID-19,” said Self, an infectious disease specialist at Vanderbilt University Medical Center.

Hydroxychloroquine is an immunosuppressive and anti-parasitic drug that is used to treat malaria.

Early in the COVID-19 pandemic, it was touted by President Donald Trump and others as a potential treatment for the virus, despite the lack of any scientific data supporting its use.

Given its effectiveness helping those sickened with malaria — a mosquito-borne infection — to recover, “there was a strong rationale for why hydroxychloroquine may have been beneficial for patients with COVID-19,” according to Self.

However, in July, the U.S. Food and Drug Administration warned against the drug’s use in the treatment of those infected with the new coronavirus, due to potentially serious heart-related side effects.

For this study, Self and his colleagues treated 433 COVID-19 patients at 34 hospitals across the United States with either the drug or a placebo for a period of five days.

Patients assigned to the hydroxychloroquine group received 400 milligrams of the drug in pill form twice a day for the first two doses and then 200 mg. in pill form twice a day for the next eight doses, for a total of 10 doses over the five days.

All of the patients were then assessed based on the WHO’s COVID Ordinal Outcomes Scale, which categorizes those infected according to disease severity.

Most of the patients in both the hydroxycholorquine group and the placebo group were in “category six,” meaning they were hospitalized and receiving extracorporeal membrane oxygenation or invasive mechanical ventilation to maintain their breathing, the researchers said.

“Our results, especially when combined from other studies conducted in the United Kingdom and Brazil, are good evidence that hydroxychloroquine does not provide benefit for patients hospitalized with COVID-19,” Self said.



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