Individuals inhale measles virus particles in aerosols and it is currently thought that these particles infect the cells that line the airways (respiratory epithelial cells) before being passed to immune cells that carry the virus particles to other parts of the body and then back to the airways, which again become infected and shed virus into exhaled aerosols.  In the study, a measles virus unable to bind to and infect epithelial cells was found to cause symptoms of measles virus infection in monkeys even though it did not infect respiratory epithelial cells and was not being shed into exhaled aerosols.  These data suggest that, in fact, inhaled measles virus particles first infect lymphocytes and are only passed to respiratory epithelial cells from the lymphocytes in the tissues.  Further, they indicate that the protein that measles virus particles bind to on respiratory epithelial cells, which has yet to be identified, is likely to be found on the surface of the cells that faces the tissues rather than the surface that faces the airways, as previously assumed.  As discussed in an accompanying commentary by Makoto Takeda, at Kyushu University, Japan, the results of this study should help researchers identify this protein.

A study from researchers at Children’s Hospital Boston published in Pediatrics found that a simple infection control intervention in elementary schools – disinfecting frequently-touched surfaces and using alcohol-based hand sanitizers – helped reduce illness-related student absenteeism.Illnesses caused by bacteria and viruses account for millions of lost school days each year.(1) According to Thomas Sandora, MD, MPH, a pediatric infectious diseases specialist at Children’s Hospital Boston, “The best ways to avoid common infections are cleaning your hands and preventing exposure to the germs that cause these illnesses. Our research indicates that elementary schools should consider a few simple infection control practices to help keep students healthier.”

The study, led by Dr. Sandora, was a randomized, controlled trial involving 285 third-, fourth-, and fifth-grade students in an elementary school system in Avon, Ohio. Teachers in intervention classrooms used disinfecting wipes on student desks, and students used hand sanitizer in the classroom at key points throughout the school day. Control classrooms followed usual hand washing and cleaning procedures.

Over eight weeks, researchers tracked the frequency of absences and the reasons for missing school. Study investigators also tested several classroom surfaces for total bacterial counts and for the presence of several common viruses.

Researchers found absenteeism rates for gastrointestinal illnesses were nine percent lower in classrooms that followed the infection control regimen of disinfecting surfaces and using alcohol-based hand sanitizers. The absenteeism rate for respiratory illness was not affected by this intervention.

Gastrointestinal illnesses are extremely common for school-age children, and children can be at risk for these infections because of frequent exposure to ill peers and poor hand hygiene.(1) In fact, the bacteria and viruses that cause these gastrointestinal infections can be easily passed from one person to another on the hands.(2) The germs can also survive on surfaces in the environment, where some of them can persist for hours to days.(1)

The study suggests that schools should consider adopting simple infection control practices, including disinfecting desktops once a day and using hand sanitizer before and after lunch, to help reduce days lost to common illnesses.

New research into the toxins, virulence, spread and prevention of the superbug Clostridium difficile is reported in the June special issue of the Journal of Medical Microbiology. These findings will play a crucial role in providing us with ammunition in the fight against a sometimes deadly pathogen.

Clostridium difficile is found in the environment but is most common in hospitals. It can cause a serious hospital-acquired infection when antibiotics are used as they upset the balance of the normal gut flora, allowing C. difficile to grow and produce toxins. It is carried in the guts of 3% of healthy humans but carriage rates in hospital patients tend to be much higher and elderly people in hospitals, being treated with antibiotics are most at risk of developing infection. The bacteria produce spores when they encounter unfavourable conditions. Transmission of infection is through the ingestion of these spores which can survive on surfaces and floors for years and are resistant to many disinfectants and antiseptics, including alcohol hand gel.

Symptoms include diarrhoea, nausea, abdominal pain, loss of appetite, fever, bowel inflammation and possible perforation, which can be fatal. Only two antibiotics are regularly used to treat C. difficile infection: metronidazole and vancomycin, but relapse is a common problem following treatment. In 2004, a hypervirulent strain (C. difficile 027/NAP1/BI) was reported, which appears to make toxins more rapidly and at higher levels than other strains, as well as being resistant to many antibiotics, including fluoroquinolones.

Several studies in the Journal of Medical Microbiology look at the spread of C. difficile in different countries, including Austria and Korea. Research shows that the use of antibiotic increased the risk of outbreaks of the hypervirulent strain of C. difficile in the Netherlands. The issue also contains evidence to suggest that C. difficile could be spread between animals and humans – researchers have isolated the bacterium from food animals in Slovenia.

Scientists investigated the effects of antibiotics, antigens and other agents on the virulence and pathogenicity of C. difficile. Toxins were also studied; research reveals some important information about the synthesis, processing and effects of different toxins. A new gene sequence has been discovered in the hypervirulent C. difficile 027 strain, which could be related to its increased virulence by affecting toxin binding.

The potential for a ‘designer’ probiotic for C. difficile is discussed. Professor Ian Poxton, former Editor-in-Chief of the Journal of Medical Microbiology said “this is an important approach that is hopefully much better than previously reported studies using commercially available yoghurt-like drinks, and certainly more palatable than ‘faecal transplants’.”