In the latest blog from the team here at Royal Society Publishing we’re continuing our celebration of Open Access Week with a focus on epidemiology. The spread of disease is important to all of us and our journals have published some very important open access research in this area. Here’s our pick of the bunch, but you can browse the subject collection here.
Typhoid is a fecal-oral human infection caused by the bacteria Salmonella Typhi and Paratyphi A. To improve understanding of typhoid transmission mechanisms in an endemic area, this Open Biology paper combines high-resolution genotyping and GPS data to show spatial clusters of typhoid, occurring independently of population density and containing a range of bacterial genotypes. Furthermore, whilst evidence is provided that direct human-to-human transmission may occur, these data demonstrate an overwhelming contribution of indirect transmission, implicating water as a transmission vehicle. This article has profound implications for typhoid control and our approach may be translated to study infection patterns of other bacterial pathogens.
The Bacille Calmette–Guérin vaccine is given to around 100 million newborn children worldwide because vaccination is consistently protective against childhood tuberculous meningitis and miliary tuberculosis, however the efficacy against pulmonary TB is variable. This Perspective piece from Fellow of the Royal Society Chris Dye in Journal of the Royal Society Interface discusses the efficacy and cost effectiveness of the Bacille Calmette–Guérin vaccine and suggests, subject to further evaluation, that BCG revaccination could be cost-effective in some settings.
This review in Proceedings B of the best scientific evidence we currently have regarding the control of bovine tuberculosis looks at what we know about the disease’s epidemiology, testing and surveillance, biosecurity, culling badgers and vaccination (of both cattle and wildlife). The authors provide a consensus judgement about the nature of each component of the evidence base, for example whether it is based on detailed experiments or expert opinion. They have tried to describe the evidence in as policy neutral manner as possible so as to best inform scientific policy.
This Philosophical Transactions B review discusses the future of vection control in the fight against malaria. The major methods of malaria control are use of insecticide treated bednets, or indoor spraying of insecticide on walls. Scaling up of these interventions over the last decade has reduced malaria deaths by a third. This progress is now threatened by the rapid selection of intense pyrethroid insecticide resistance. A Public-Private Partnership is working with industry to develop the next generations of public health insecticides, but these will take at least 6 – 9 years to reach the market. Plans to manage this growing resistance issue need to be put in place in the interim using available mosquito control interventions.
For vector-borne diseases to spread, the abundance of the host and vector should be sufficiently high. In wildlife populations, host and vector abundances often vary greatly across years and consequently the threshold may be crossed regularly, both up- and downward, enabling the infection to spread or fade out. This Biology Letters paper shows that for plague in Kazakhstan, the vector (flea) and host (great gerbil) abundances are inextricably linked with a delay, resulting in vector-host cycles, reminiscent of predator-prey cycles, which drive the system around the infection threshold, producing epizootic cycles as observed in the field.
And coming soon in Royal Society Open Science, researchers use Google Flu Trends combined with historical data to accurately predict the spread of infection faster than official figures. You can sign up for alerts to find out when the paper publishes.
Don’t forget we’re making all of our content free for Open Access Week, so visit the individual journal pages to access all of our content this week. The final post in our Open Access week series will be posted tomorrow on cellular and molecular biology.