Dec 28, 2012
Norovirus rampage continues in UK
The number of confirmed norovirus cases in the United Kingdom is running 83% ahead of the number at this point last year, says a report today from the UK's Health Protection Agency (HPA). Cases typically pick up in January but are increasing earlier than usual this season, a trend that is being seen across Europe and other parts of the world, according to the notice. The number of confirmed cases reported from week 27 through week 50 of 2012 is 3,538; last year at this time the total was 1,934. Outbreaks this season number 538 so far. As noted by HPA, lab-confirmed cases represent only a fraction of total cases, as most affected people do not seek medical help; HPA estimates the number of unreported cases for each confirmed case at 288. John Harris of the HPA states in the notice, "To help prevent spread of the disease, it's important that people who believe they are unwell with the virus maintain good hand hygiene and stay away from hospitals, schools and care homes, as these closed environments are particularly prone to outbreaks which can cause severe disruption."
Dec 28 HPA press release
Related Dec 18 CIDRAP News item
Study suggests how S aureus colonizes nose
Scientists at Trinity College Dublin say they have found the molecular handle that allows Staphylococcus aureus to grab onto cells in the nasal passages of mice, a discovery that may open the way for measures to reduce S aureus nasal colonization and related infections in humans. About 20% of people persistently carry the microbe in their nasal passages, the authors note in a report in PLoS Pathogens. Previous research has shown that clumping factor B (ClfB) is one of the proteins that enables S aureus to adhere to squamous epithelial cells in the human nose. The authors say they determined that loricrin, a major component of the squamous epithelial cell envelope, is the primary target for ClfB and that the interaction between ClfB and loricrin is necessary for efficient nasal colonization in mice. They found that purified ClfB bound loricrin with high affinity. In mice that were genetically engineered to be loricrin-deficient, S aureus nasal colonization was significantly impaired. And an S aureus mutant that lacked ClfB could not colonize mice at all, according to a PLoS Pathogens press release. The scientists say their discovery, with its potential for leading to ways of preventing colonization, is important in view of the problems with methicilin-resistant S aureus (MRSA).
Dec 27 PLoS Pathogens report
Dec 27 PLoS Pathogens press release via EurekAlert
Researchers find pandemic H1N1 established in Brazil's swine population
In a study billed as the most comprehensive genetic analysis of swine influenza strains in Brazil, scientists found that the pandemic H1N1 (pH1N1) virus was widespread in the country's swine in 2009 and 2010. The authors collected 20 flu isolates from clinically ill pigs in five Brazilian states and conducted phylogenetic analyses of the viruses' hemagglutinin and neuraminidase proteins, according to their report published today in Influenza and Other Respiratory Viruses. They found that all the isolates clustered with pH1N1 and appeared to have a common ancestor. The authors also examined a flu isolate from a technician who had become ill after visiting a swine herd in which respiratory disease was present. They found that the human isolate was more closely related to strains from the swine herd than to other human isolates, suggesting swine-to-human transmission. The overall findings, they say, indicate that flu was widespread in Brazil's swine herds in 2009-10. "Our results suggest that the pandemic H1N1 subtype has become established in the Brazilian swine population and may become endemic in the country," they conclude.
Dec 28 Influenza Other Respi Viruses abstract
Johns Hopkins nets Gates grant to boost cholera vaccine use
The Johns Hopkins Bloomberg School of Public Health yesterday announced that it has received a 4-year grant worth $5 million to fund a program to promote the effective international use of oral cholera vaccine. The Delivering Oral Vaccine Effectively (DOVE) program will offer relief agencies and governments technical assistance on the use of oral cholera vaccine, evaluate current vaccine-use practices, and develop new methods for monitoring and controlling cholera outbreaks, according to a press release. DOVE will also establish cholera surveillance in northern Cameroon near Lake Chad, which has been a cholera hotspot. Many public health experts have maintained that outbreak response should focus on rehydration therapy, clean water, and improved sanitation, but some are rethinking immunization in light of vaccine improvements, according to previous reports. The oral vaccine is more than 70% effective and is inexpensive but not widely used, the school said. David Sack, MD, director of DOVE and professor in the department of international health at Bloomberg, said in the statement, "We believe this grant will greatly facilitate the appropriate use of the new cholera vaccine. In partnership with the World Health Organization, UNICEF and other national and international agencies, we believe the DOVE project will provide the knowledge, technical assistance and encouragement to bring this life-saving vaccine to those who need it most."
Dec 27 EurekAlert press release