Tag: sneezing

Categories : Paediatrics Respiratory DiseasesTags :

Saline Nasal Drops Shorten the Common Cold in Children by Two Days

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Photo by Andrea Piacquadio on Unsplash

Using hypertonic saline nasal drops can reduce the length of the common cold in children by two days, according to a study presented at the European Respiratory Society (ERS) Congress in Vienna, Austria [1]. They can also reduce the onward transmission of colds to family members.

The results of the ELVIS-Kids randomised controlled trial were presented by Professor Steve Cunningham from Child Life and Health, University of Edinburgh, UK.

He said: “Children have up to 10 to 12 upper respiratory tract infections, what we refer to as colds, per year, which have a big impact on them and their families. There are medicines to improve symptoms, such as paracetamol and ibuprofen, but no treatments that can make a cold get better quicker.”

ELVIS-Kids Chief Investigator Dr Sandeep Ramalingam, consultant virologist, NHS Lothian, Edinburgh, UK, had noted that salt-water solutions are often used by people in South Asia, as nasal irrigation and gargling, to treat a cold and wanted to explore if this clinical benefit could be replicated in a large study.

The research team recruited 407 children aged up to six years to a study where they were given either hypertonic saline ~2.6% (salt-water) nasal drops or usual care when they developed a cold. Overall, 301 children developed a cold; for 150 of these, their parents were given sea salt and taught to make and apply salt-water nose drops to the children’s noses (three drops per nostril, a minimum of four times per day, until well) and 151 children had usual cold care.

Professor Cunningham explains: “We found that children using salt-water nose drops had cold symptoms for an average of six days where those with usual care had symptoms for eight days. The children receiving salt water nose drops also needed fewer medicines during their illness.

“Salt is made up of sodium and chloride. Chloride is used by the cells lining the nose and windpipes to produce hypochlorous acid within cells, which they use to defend against virus infection. By giving extra chloride to the lining cells this helps the cells produce more hypochlorous acid, which helps suppress viral replication, reducing the length of the virus infection, and therefore the duration of symptoms.”

When children got salt-water nose drops, fewer households reported family members catching a cold (46% vs 61% for usual care). Eighty-two per cent of parents said the nose drops helped the child get better quickly and 81% said they would use nose drops in the future.

Professor Cunningham added: “Reducing the duration of colds in children means that fewer people in their house also get a cold, with clear implications for how quickly a household feels better and can return to their usual activities like school and work etc.

“Our study also showed that parents can safely make and administer nose drops to their children and therefore have some control over the common cold affecting their children.”

Professor Alexander Möeller is Head of the ERS Paediatric Assembly and Head of the Department for Respiratory Medicine at the University Children’s Hospital Zurich, Switzerland, and was not involved in the research. He said: “This is an important study that is the first of its kind to investigate the impact of salty nose drops in children with colds. Although most colds usually don’t turn into anything serious, we all know how miserable they can be, especially for young children and their families.

“This extremely cheap and simple intervention has the potential to be applied globally; providing parents with a safe and effective way to limit the impact of colds in their children and family would represent a significant reduction in health and economic burden of this most common condition.”

The team hope to further investigate the effect of saltwater nose drops on wheeze during colds, after initial results from this study showed that children who received the drops had significantly fewer episodes of wheeze (5% vs 19%).

Reference

[1] Abstract no: OA1985 “A randomised controlled trial of hypertonic saline nose drops as a treatment in children with the common cold (ELVIS-Kids trial)”, by Dr Sandeep Ramalingam et al; Presented in session “Advancements in paediatric infectious respiratory health” at 15:45–17:00 CEST on Sunday 8 September 2024.

https://live.ersnet.org/programme/session/92864

Source: European Respiratory Society

Categories : NeurologyTags :

What Causes Us to Sneeze?

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Photo by Andrea Piacquadio from Pexels

A new study has identified, in mice, specific cells and proteins that control the sneeze reflex. 

Better understanding of what causes us to sneeze, and especially how neurons behave in response to allergens and viruses, may lead to treatments which can slow the spread of infectious respiratory diseases.

A tickle in the nose can help trigger a sneeze, which expels irritants and disease-causing pathogens. But the cellular pathways that control the sneeze reflex go far beyond the sinuses and have been poorly understood. Now, a team led by researchers at Washington University School of Medicine in St. Louis has identified, in mice, specific cells and proteins that control the sneeze reflex.

“Better understanding what causes us to sneeze — specifically how neurons behave in response to allergens and viruses — may point to treatments capable of slowing the spread of infectious respiratory diseases via sneezes,” said Qin Liu, PhD, an associate professor of anesthesiology and the study’s senior investigator.

“We study the neural mechanism behind sneezing because so many people, including members of my own family, sneeze because of problems such as seasonal allergies and viral infections,” explained Prof Liu, a researcher in the university’s Center for the Study of Itch and Sensory Disorders. “Our goal is to understand how neurons behave in response to allergies and viral infections, including how they contribute to itchy eyes, sneezing and other symptoms. Our recent studies have uncovered links between nerve cells and other systems that could help in the development of treatments for sneezing and for fighting infectious respiratory diseases.”

Sneezing is the most common and forceful way of spreading infectious droplets from respiratory infections. Over two decades ago, researchers discovered a sneeze-evoking region in the central nervous system, but since then there has been little progress in understanding the mechanism of the sneeze reflex at the cellular and molecular level.

For the new study, Prof Liu and her team used a mouse model to figure out which nerve cells send signals that make mice sneeze. The researchers exposed the mice to aerosolised droplets containing either histamine or capsaicin, a pungent compound made from chili peppers, both of which caused the mice to sneeze.

By examining nerve cells that already were known to react to capsaicin, Liu’s team was able to identify a class of small neurons linked to sneezing that was caused by that substance. The researchers then searched for neuropeptides that could transmit sneeze signals to those nerve cells, and hit upon a molecule called neuromedin B (NMB), which they found was required for sneezing.

By eliminating the NMD-sensitive neurons in the part of the nervous system that evoked sneezes in the mice, they blocked the sneeze reflex. Those neurons all make a protein called the neuromedin B receptor. In mice lacking that receptor, sneezing again was greatly reduced.

“Interestingly, none of these sneeze-evoking neurons were housed in any of the known regions of the brainstem linked to breathing and respiration,” Prof Liu said. “Although we found that sneeze-evoking cells are in a different region of the brain than the region that controls breathing, we also found that the cells in those two regions were directly connected via their axons, the wiring of nerve cells.”

By exposing part of the mouse brain to the NMB peptide, the researchers found they could directly stimulate the sneeze reflex, even though they had not been exposed to any capsaicin, histamine or other allergens.

Since many viruses and other pathogens are spread in part by aerosolised droplets, Prof Liu said it may be possible to limit the spread of those pathogens by targeting NMB or its receptor to limit sneezing in those known to be infected.

“A sneeze can create 20 000 virus-containing droplets that can stay in the air for up to 10 minutes,” Liu Prof explained. “By contrast, a cough produces closer to 3000 droplets, or about the same number produced by talking for a few minutes. To prevent future viral outbreaks and help treat pathological sneezing caused by allergens, it will be important to understand the pathways that cause sneezing in order to block them. By identifying neurons that mediate the sneeze reflex, as well as neuropeptides that activate these neurons, we have discovered targets that could lead to treatments for pathological sneezing or strategies for limiting the spread of infections.”

Source: Washington University School of Medicine

Journal information: Li, F., et al. (2021) Sneezing reflex is mediated by a peptidergic pathway from nose to brainstem. Cell. doi.org/10.1016/j.cell.2021.05.017.