Navigation Links
Bacterial colonization prior to catching the flu may protect against severe illness

Many studies have shown that more severe illness and even death are likely to result if you develop a secondary respiratory infection after developing influenza. Now, however, a team of researchers based at The Wistar Institute has determined that if you reverse the order of infection, the bacteria Streptococcus pneumoniae (often called pneumococcus) may actually protect against a bad case of the flu.

The researchers discovered that the bacterial protein pneumolysin, which is described as a bacterial virulence factor, might protect macrophagesa type of immune system cellin the lungs. Their findings, performed in a mouse model of influenza infection, appear in the August issue of the journal Virology, available online now.

"Influenza remains a major killer, and there is a preponderance of evidence, both scientific and historical, to show how secondary bacterial infections can be fatal," said Jan Erikson, Ph.D., professor at The Wistar Institute. "However, pneumococci often colonize the respiratory tract asymptomatically, particularly in children, leading us to consider how pre-colonization would impact a subsequent influenza infection."

"Our studies showed that prior colonization offered a protective effect against severe disease in mice," Erikson said, "and we were able to point to the bacterial virulence factor pneumolysin in mediating this protection."

In their investigations, Erikson and her colleagues found that mice who were colonized by Streptococcus pneumonia ten days prior to exposure to influenza were significantly less likely to develop severe disease or pneumonia than mice who were not colonized by the bacteria. In contrast, disease symptoms were exacerbated in mice that were exposed to the flu prior to a secondary pneumococcal infection.

"Mice that were first exposed to pneumococci exhibited less inflammation in the lungs following influenza infection. Virus infection wasn't blocked but the response to it was changed such that the mice no longer showed signs of illness," Erikson said.

The researchers then went about investigating how this might occur. Using mutant strains of pneumococcus that lacked certain proteins, Erikson and her colleagues were able to single out one bacterial protein, pneumolysin, which was necessary to generate the protective effect of pneumococcus. While the exact mechanisms by which pneumolysin lessens the severity of disease remain unknown, Erikson and her colleagues were able to show how alveolar macrophages were less likely to recruit inflammation-causing immune cells to the lungs. Less inflammation would mean less chances of developing pneumonia, which is a major source of flu deaths, Erikson says.

According to Erikson, her results suggest that one factor contributing to the highly variable response to influenza virus infection and severity of disease observed in humans is the presence of specific respiratory tract microbes. "It remains to be seen what lessons we can learn from pneumococcus in lessening flu infections," Erikson said, "but I would be interested in seeing if we could get the benefit of pneumococcal colonization without the associated risks."


Contact: Greg Lester
The Wistar Institute

Related medicine news :

1. Pharmacy Robots Linked to Bacterial Contamination of Drugs
2. Children with juvenile arthritis have higher rates of bacterial infection
3. University of Minnesota startup to treat challenging bacterial infection
4. Fish Pedicure a Recipe for Bacterial Infection, Researchers Warn
5. Zooming in on bacterial weapons in 3-D
6. Killer stainless steel: New process gives icon of cleanliness antibacterial coating
7. Study Ties Kids Allergy Risks to Antibacterials, Preservatives
8. Bacterial Vaginosis Increases Female-to-Male HIV Transmission Risk
9. New mechanism of bacterial pathogenesis discovered
10. AuCoin gets $600,000 to refine new test for deadly bacterial infection melioidosis
11. NIH uses genome sequencing to help quell bacterial outbreak in Clinical Center
Post Your Comments:
(Date:6/24/2016)... ... June 24, 2016 , ... Dr. Amanda Cheng, ... treatment. Dr. Cheng has extensive experience with all areas of orthodontics, including robotic ... osteogenic orthodontics. , Micro-osteoperforation is a revolutionary adjunct to orthodontic treatment. It ...
(Date:6/24/2016)... NY (PRWEB) , ... June 24, 2016 , ... Topical BioMedics, Inc, makers of Topricin ... companies that call for a minimum wage raise to $12 an hour by 2020 and ... This will restore the lost value of the minimum wage, assure the wage floor does ...
(Date:6/24/2016)... ... June 24, 2016 , ... EB Medicine presented ... in Emergency Medicine conference in Ponte Vedra Beach, FL. The awards honor the ... Emergency Medicine Practice and Pediatric Emergency Medicine Practice. , “With this award, ...
(Date:6/24/2016)... Vegas, Nevada (PRWEB) , ... June 24, 2016 ... ... Las Vegas client, The Grove Investment Group (TGIG), has initiated cultivation and processing ... Grove, in Las Vegas and Pahrump, Nevada. , Puradigm is the manufacturer of ...
(Date:6/24/2016)... ... 24, 2016 , ... National recruitment firm Slone Partners is pleased ... and genomics experience, as Vice President of North American Capital Sales at HTG ... leading the sales team in the commercialization of the HTG EdgeSeq system and associated ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... , June 24, 2016 ... the "Structural Electronics 2015-2025: Applications, Technologies, Forecasts" ... In-Mold Electronics, Smart Skin, Structural ... Structural electronics involves electronic and/or ... protective structures, replacing dumb structures such as vehicle ...
(Date:6/24/2016)... India , June 24, 2016 ... Needles Market by Type (Standard Pen Needles, Safety Pen ... Therapy (Insulin, GLP-1, Growth Hormone), Mode of Purchase (Retail, ... by MarketsandMarkets, This report studies the market for the ... expected to reach USD 2.81 Billion by 2021 from ...
(Date:6/23/2016)... 23, 2016 Research and Markets has ... - Forecast to 2022" report to their offering. ... for the patients with kidney failure, it replaces the function ... the patient,s blood and thus the treatment helps to keep ... in balance. Increasing number of ESRD patients ...
Breaking Medicine Technology: