eMJA: In Other Journals, 17 September 2007

Direct-to-consumer advertising of prescrip-tion drugs has come under pressure in the United States, with researchers suggesting that the Food and Drug Administration (FDA) has fallen behind in enforcement of laws regulating such advertising. A study of trends in pharmaceutical spending reveals a staggering US$29.9 billion spent on drug advertising in 2005, with spending on direct-to-consumer advertising increasing by 330% to over US$4 billion since 1996. In the midst of calls for tighter controls on direct adver-tising, the study shows that manufacturers of proton-pump inhibitors, statins, and erythropoietin medications spent about a third of their total marketing budget on direct advertising in 2005. New drugs developed to treat chronic conditions are the most likely candidates for this type of promotion, with most being advertised directly within a year of their introduction into the market. The authors comment that this may lead to increased use of drugs with uncertain safety profiles. A decline in the number of regulatory actions by the FDA against com-panies marketing direct to consumers has led researchers to speculate that the FDA has fallen behind in the task of reviewing and policing inappropriate and misleading advertising. They suggest that this may be the result of insufficient FDA staffing levels and the introduction of more complicated requirements before warning letters can be issued to pharmaceutical companies.

Good bacteria for diarrhoea

The efficacy of probiotics in the treatment of diarrhoea in children is related to the strain of bacteria in the preparation, according to Italian researchers. Their randomised clinical trial involved over 500 children aged from 3 to 36 months presenting with acute diarrhoea of less than 48 hours’ duration to a family paediatrician. In the Italian health system, family paediatricians care for children up to 12 years of age. A control group received oral rehydration alone, and five treatment groups were given various oral formulations of probiotic bacterial strains for 5 days. Primary outcome measures were total duration of diarrhoea and the number of stools per day and their consistency. When compared to the control group, the duration and severity of diarrhoea was significantly lower in children receiving Lactobacillus rhamnosus GG and in those receiving a bacterial mix (L. delbueckii var bulgaricus, L. acidophilus, Streptococcus thermophilus and Bifidobacterium bifidum). The authors comment that although there is a possibility of confounders such as parental expectations affecting the findings, the size and resultant power of the study supports the validity of the result. They call for the reclassification of probiotics as drugs rather than food additives, and comment that there is a growing evidence base for the efficacy of these preparations in the treatment of childhood diarrhoea.

BMJ 2007; 335: 340

Open season on ’flu

The well documented seasonal patterns of human influenza infection in temperate regions may not be as simple or clear-cut in tropical climates, with important ramifications for transmission and the development of pandemic strains. Despite the large amount of data available on the incidence of influenza in humans in temperate areas, little is known about the temporal patterns of human influenza A in east and south-east Asia. In a review by scientists from Australia and France, outbreaks of highly pathogenic avian influenza A (H5N1) were identified and analysed for evidence of seasonality, human infection, and host range. Although outbreaks of disease in humans largely coincided with those in domestic poultry in winter months, several outbreaks in China extended into or re-occurred in the summer. Other Asian countries showed varying patterns of seasonality, and patterns were not uniform across the region. H5N1 isolation from domestic ducks across Asia is steadily increasing. Pandemic strains of the influenza virus can arise by adaptive mutation of zoonotic influenza in a human host, or by genetic reassortment in a person simultaneously infected with a human and an avian strain. When more host species are available, the potential for mutation is increased, as is the risk of pandemic infection in human beings, particularly with close contact between the species. When the season for infectivity in a region is extended, the risk of pandemic is also greater. The researchers comment that the relative timing of human and avian influenza incidence is a key factor in assessing the risk of viral reassortment and subsequent development of a pandemic.

Lancet Infect Dis 2007; 7: 543-548

Dr Tanya Grassi, MJA

The Medical Journal of Australia eMJA