Introduction

Respiratory Syncytial Virus (RSV) is a highly contagious virus that primarily affects the respiratory tract, leading to mild cold-like symptoms. It is known as one of the most common viral respiratory infections worldwide as almost all children are infected with it by the time they are two years old.¹ According to a recent study,  there are roughly 33 million cases, 3.6 million hospital admissions, and 100,000 deaths globally each year in children under 5 years old. It is the second largest infectious cause of death in children under one year of age, after malaria.² While most individuals recover within a week or two, or can be treated as outpatient cases, infants and the elderly are at a higher risk of developing severe symptoms that may require hospitalization, especially those with weakened immune system.³ Understanding and recognising the methods of transmission, also implementing preventive strategies can significantly reduce the risk of RSV spreading within a household.

Signs and symptoms

Symptoms usually appear two to eight days after being infected. RSV affects different age groups differently, but the most common symptoms of the condition include:^{7, 8, 12}

• Cough
• Runny or blocked nose
• Sneezing
• Fever
• Sore throat
• Headache
• Fatigue
• Wheezing

Who are the high-risk groups/situations?

Infants or young children: as their immune system is not fully developed, it makes them particularly susceptible to severe RSV infections. Some children may have a higher risk of getting seriously ill because of RSV, this includes children who:^{2, 16}

1. Were born prematurely
2. Have a heart or lung condition
3. Have a weakened immune system
4. Elderly people are also found at risk of infection as due to ageing their immune systems get weakened
5. Family members with immunocompromised/weakened immune systems. Pre-existing conditions such as diabetes, heart disease, and lung disease can exacerbate the severity of RSV⁹

Understanding RSV transmission

RSV is commonly transmitted in community settings such as schools and childcare centres, where children are frequently exposed and can bring the virus home, potentially infecting other family members.^1,5

RSV can spread through several ways:

Direct contact⁵

1. If an uninfected person touches someone who is infected, then they can acquire the virus. For example, if an infected person has RSV droplets on their hands from coughing or sneezing and then shakes hands with another person, the virus can be transferred to the healthy person
2. Close physical interactions, such as kissing an infected person can also directly transfer the virus
3. Caring/handling for Infected Individuals: Assisting with personal hygiene can facilitate the transmission of RSV through direct contact with respiratory secretions. Parents or caregivers can also easily come in contact with and pass on the virus to others. For example:
   • Changing nappies
   • Bathing
   • Feeding
   • Wiping nose
   • Touching someone else’s face after managing an infected person's secretions can lead to infection
4. Family gatherings or close contact during meals or play can also make the virus spread easily among household members
5. Droplet transmission: this could happen when someone sneezes or coughs and releases tiny droplet particles that contain the virus into the air. This droplet can land in someone’s face or nose and then be inhaled directly into their lungs

Indirect contact

1. Contaminated surfaces: when someone touches contaminated surfaces such as a doorknob, toys, light switch, countertop, etc, and then touches his/her face or mouth without washing or sanitizing their hands. RSV can survive on surfaces like doorknobs, toys, and countertops for several hours. It typically lives on soft surfaces such as tissues and hands for shorter amounts of time⁵
2. Shared Objects: Eating utensils, toothbrushes, cups, or towels can also facilitate the transfer of the virus if shared among household members. An infected person might leave the virus on these objects, which can then be picked up by another household member
3. Bedding and Clothing: RSV can also survive on fabric surfaces, sharing sleeping arrangements such as shared bedding and clothing becoming a potential source of transmission

Treatment

There are no specific treatments for RSV infection. In most cases healthy children and adults will clear up within a week or two, treatment is therefore aimed at supporting the patient and relieving symptoms, over-the-counter medication such as Ibuprofen or paracetamol can help discomfort and fever symptoms.¹ Drinking plenty of fluid is also important to prevent dehydration.¹⁰ In the hospital setting patients might be treated with intravenous fluid, antiviral drug, oxygen therapy or mechanical ventilation for severe cases alongside specific treatments for complications that may arise.^1,8

Preventive measures

First and foremost, prevention is always better than treatment, below are some actions that we can take as precautionary actions.

Everyday preventive actions

• Avoiding close contact with infected people
• Avoid sharing cups, bottles, toys, and eating utensils that have been contaminated with the virus. Sometimes this can be difficult, alternatively should ensure that shared items are regularly cleaned and disinfected
• Thoroughly wash hands with soap and water at least for 20 seconds after coming into contact with an infected person or use alcohol-based hand sanitiser if soap and water are not available.
• Use disposable tissues rather than handkerchiefs and throw them away after using it⁴
• Regularly cleaning high touch) Covers your or your child’s nose while coughingsneezing or surfaces with household disinfectants
• Stay at home when you are sick until your symptoms improve, or keep the infected person in a separate room and minimize contact with healthy family members⁸
• Using mask
• Ensuring good air ventilation
• It is also very important NOT to smoke around your child as children who breathe cigarette smoke have a higher risk of getting Bronchiolitis¹⁴
• Exclusive breastfeeding reduces the risk of severe infection and hospitalization with RSV. If you just give birth and would like to breastfeed and need support, speak with healthcare professionals who will be able to help. If your baby is in the neonatal unit and unable to breastfeed then you may want to express your milk⁷

RSV Immunization

1. Infants and some young children: RSV preventive antibody. In the UK Palivizumab (a monoclonal antibody therapy) is licenced immunization for the prevention of serious lower respiratory tract infection caused by RSV in infants at high risk of infection.⁸
2. Adults: In the UK, a new monoclonal antibody, called Nirsevimab, that could be used widely has recently been licensed alongside an RSV vaccine for pregnant women, to protect their infants and older adults. The Joint Committee on Vaccination and Immunization (JCVI) advised that an RSV immunization programme, that is cost-effective, is possible for both infants and older adults and the process for deciding which product to use is underway with an outcome expected in Summer 2024.⁸ In the US¹⁰
   • Adults age 60 and older: Two RSV vaccines (GSK Arexvy and Pfizer Abrysvo) have been licensed by FDA and recommended by CDC for adults ages 60 and older, using shared clinical decision-making
   • Pregnant women: One RSV vaccine (Pfizer Abrysvo) has been licensed and recommended during weeks 32 through 36 of pregnancy to protect infants
   • Infants and some young children: An RSV preventive antibody has been licensed and recommended for infants and some young children

Educate family members about the signs and symptoms, and transmission methods, inform other family members when they are feeling ill, and lastly work together to maintain a clean and healthy living environment.

When to seek further advice/help from healthcare professionals/doctors?

• For babies: when they become less active, irritability, breathing difficulties/distress, reduction in feeding and drinking, showing symptoms or dehydration such as fewer wet nappies, drowsy, has lips or fingernails that look blue^14,15
• For adults: Shortness of breath, high fever, difficulty breathing, cough that keeps getting worse, bluish tint to your skin^10,15

Summary

RSV is a highly contagious illness that causes infection of the lungs and breathing passage.¹³ One of the common viruses that cause coughs and colds in winter. RSV is not only a virus of the infant but of the entire family.⁶ In the EU, Norway and the United Kingdom, RSV is responsible for the hospitalization of around 213,000 children under five with some requiring intensive care, and roughly 158,000 adults each year.⁹ Understanding the modes of RSV transmission within a household, which has two main methods direct and indirect transmission, as well as implementing preventive measures can significantly reduce the risk of infection. By maintaining good hygiene practices, ensuring proper cleaning and disinfection, and improving indoor air quality, families can protect their vulnerable members and maintain a healthy living environment.