Medical Bulletin 19/July/2023

Here are the top medical news for the day:

Throat-dwelling bacteria to be the primary source of Strep A transmission

Breakthrough research has found that Group A Streptococcus (GAS) infections are more likely transmitted from asymptomatic throat carriage than skin-to-skin contact in communities with high rates of infection.

GAS (Streptococcus pyogenes), commonly found on the skin and in the throat, can cause infections ranging from sore throats and impetigo (skin infections) to deadly bloodstream infections. In places like remote First Nations communities where the pathogen is widespread, constant exposure to GAS can lead to severe and life-threatening conditions such as rheumatic heart disease.

In this study, published in the journal The Lancet Microbe, the team of scientists sheds new light on GAS transmission dynamics in high-risk settings where the bacteria are prevalent, to inform the development of more effective strategies for prevention and control.

Reference: Evaluating the role of asymptomatic throat carriage of Streptococcus pyogenes in impetigo transmission in remote Aboriginal communities in Northern Territory, Australia: a retrospective genomic analysis, The Lancet Microbe, DOI 10.1016/S2666-5247(23)00068-X 

Novel genes with a role in deadly heart defects identified

By identifying genes in patients and testing their effects in fruit flies, researchers from Sanford Burnham Prebys have found new genes that contribute to hypoplastic left heart syndrome (HLHS), a rare, life-threatening heart disease that occurs in infants. The findings, published in the journal eLife, bring scientists one step closer to unraveling the biology of this complex disease.

In babies with HLHS, the left side of the heart (left ventricle) is underdeveloped and unable to pump oxygenated blood to the rest of the body. Though rare, HLHS is extremely dangerous—it is nearly always fatal without multiple open-heart surgeries.

Reference: Mitochondrial MICOS complex genes, implicated in hypoplastic left heart syndrome, maintain cardiac contractility and actomyosin integrity, eLife, DOI 10.7554/eLife.83385. 

Toothpaste with synthetic tooth minerals can prevent cavities as effectively as fluoride

Fluoride in toothpaste can pose health problems in some cases, especially for children who consume too much fluoride by swallowing most of their toothpaste: children normally use only a tiny dose of toothpaste to avoid these problems, but that reduces toothbrushing efficacy. In the search for alternatives, a team of international scientists and Polish clinicians have identified a hydroxyapatite toothpaste that works just as well as fluoride toothpaste to protect against cavities.

Hydroxyapatite is a calcium phosphate mineral found in the skeleton. It’s known to be very safe for human consumption and has previously been shown to help with oral conditions like periodontitis. It can both inhibit the demineralization of teeth, a key step towards a cavity and contribute to remineralization, which reinforces damaged tooth surfaces.

Reference: Caries-preventing effect of a hydroxyapatite-toothpaste in adults: A 18 months double-blinded randomized clinical trial, Frontiers in Public Health, DOI 10.3389/fpubh.2023.1199728