Health Scan: Natural flu killers

A known difficulty in fighting influenza is the ability of flu viruses to mutate and thus evade medications.

June 2, 2013 03:45
4 minute read.
Medication [illustrative]

Fish oil capsules pills medicine health 390. (photo credit: Courtesy)

A known difficulty in fighting influenza is the ability of flu viruses to mutate and thus evade medications previously found to be effective against them. But Hebrew University researchers have shown recently that another, more promising, approach is to focus on improving drugs that boost the body’s natural flu-killer system.

Emergence of new influenza strains, such as the recent avian influenza (H5N1) and swine influenza (H1N1 2009), can lead to the emergence of severe pandemics that pose a major global threat. The concern regarding the emergence of such a pandemic arose when a new and deadly avian influenza strain (H7N9) was discovered in China not long ago, causing the death of six people in only a month.

The body’s immune system can fight influenza infection. Natural killer (NK) cells, which are an essential component of this system, can recognize and eliminate influenza virus-infected cells and inhibit the spread of the virus in the respiratory system. But, as doctoral student Yotam Bar-On and Prof. Ofer Mandelboim of the HU Medical Faculty’s Institute for Medical Research Israel Canada (IMRIC) have revealed in a paper published in Cell Reports, the influenza virus is able to escape from the NK cells’ activity, allowing it to spread in the respiratory system.

They show that this is accomplished by the influenza virus utilizing the enzymatic activity of the neuraminidase protein to neutralize the NK cells’ receptors that are responsible for detecting the infected cells. This, in effect, neutralizes the NK cells’ ability to accomplish their designated flu-killing duty.

With the aid of the neuraminidase protein, the influenza virus is free to exit the infected cell, enabling it to infect new neighbor cells and spread in the respiratory system.

Anti-flu drugs were developed to inhibit this spread of the virus by inhibiting the neuraminidase enzymatic activity. But, as with other, earlier anti-influenza drugs, the flu viruses are able to gain the upper hand. The extensive use of neuraminidase inhibitors has caused the emergence of new, drug-resistant influenza strains.

For example, during the spread of the swine influenza pandemic about four years ago, the UK Health Protection Agency reported that 99 percent of the viruses analyzed were resistant to these inhibitors. It was shown that the virus was able to change the neuraminidase structure so the drug can no longer bind this protein, and therefore the desired inhibitory effect is lost.

Despite this, Bar-On and Mandelboim have shown that this type of widely used drug has the effect of boosting the activity of the NK cells, enabling them to better eliminate the influenza virus. They stress, therefore, that efforts should be focused on developing effective new drugs that would maintain and enhance this NK cell activity, thereby leading to more effective elimination of the influenza virus and better recovery from flu infection without the susceptibly to the changes in the neuraminidase protein structure currently brought about by mutating flu viruses.


A growing number of young women mistakenly believe that having a normal vaginal birth – with or without a surgical episiotomy – harms their sexual relations after delivery, and they therefore demand that their doctors perform a Caesarean section, according to Prof. Shmuel Luria, a senior obstetrician/ gynecologist at Holon’s Wolfson Medical Center. Luria said this is not so, and that a Caesarean offers no sexual benefits over vaginal delivery.

He and his team handed out questions to women six, 12 and 24 weeks after delivery. According to the responses, sexual function improved the more time passed after delivery, and there were no differences in sexual function and enjoyment when the delivery was normal or via surgery.

Luria said that at Wolfson, Caesareans constitute 5.5% of all types of surgery, and that too many of them are not medically justified.

This study is unique, Luria said, concluding that “we can now calm mothers down, and explain that vaginal births don’t have a bad effect on sexual relations in any way after delivery.”


If you need to have an inflamed appendix taken out some day in the not-too-distant future, surgeons will probably be able to use a pinhole incision through the navel to get it out. Published in the British Journal of Surgery, the findings indicate that larger studies to test the potential of the procedure are still needed.

The experimental, minimally invasive and scarless surgical procedure for appendicitis, called transgastric appendectomy, avoids the use of external incisions and causes less pain than traditional appendectomies, the German researchers said. Through the insertion of a needle, an endoscope is passed through the stomach into the abdominal cavity.

“Surgeons and their patients had good experiences with surgery by pinholes beginning in the 1990s, and there is interest in continuing this development to avoid incisions in the abdominal wall completely and to obviate wound infections and incisional hernias,” said Dr. Georg Kaehler of the University of Heidelberg’s University Medical Center Mannheim. “Therefore, we used flexible tubes called gastroscopes to get through the stomach into the abdominal cavity and to perform surgical operations there.”

They performed transgastric appendectomy in a group of 14 patients with uncomplicated appendicitis.

Two patients with abdominal inflammation required cleansing treatments four days after the procedure.

Hospital stays and postoperative complications were similar to those of classical surgical methods for appendicitis.

These preliminary results demonstrate the potential of this innovative procedure, particularly for appendicitis not accompanied by an infection called generalized peritonitis; however, more information is needed on the specific advantages and disadvantages of the approach.

Kaehler and his coauthors noted that a multicenter study is now being planned, which will – it is hoped – prove the feasibility and safety of transgastric appendectomy.

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